Patent Publication Number: US-2020281772-A1

Title: Insertion system for deploying a ventilation device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a continuation of and claims priority to U.S. patent application Ser. No. 15/094,085, filed Apr. 8, 2016, which is a divisional application of and claims priority to U.S. patent application Ser. No. 13/826,497, filed Mar. 14, 2013, which is based on and claims the benefit of U.S. provisional patent application Ser. No. 61/660,280, filed Jun. 15, 2012, the contents of which are hereby incorporated by reference in their entireties. 
    
    
     BACKGROUND 
     Placement of middle ear ventilation tubes in the tympanic membrane is a common pediatric surgical procedure for the treatment of middle ear infection or otitis media. Also known as tympanostomy tubes or pressure equalizing (PE) tubes, the procedure involves creating an incision (i.e., a myringotomy) in the tympanic membrane and placing a tube in the incision to allow ventilation, pressure equalization and drainage from the middle ear out through the ear canal. The tube can remain in the ear for months or years. 
     A tube is placed in the tympanic membrane via visualization through a microscope. A sharp blade is used to create the incision and various surgical instruments are used to manipulate the tube into the incision. In the confined space of the ear canal, placement of the tube can be difficult, especially in aligning the flange at one end of the tube with the incision and the need for multiple different surgical instruments to perform the procedure. It is also not uncommon for the tube to dislodge from the surgical instrument or for it to accidentally extract from the tympanic membrane before being fully seated, requiring multiple attempts before successful placement is achieved. In addition, the large retention flanges included in most tubes make them difficult to maneuver in the ear canal and will actually block the clinician&#39;s view of the incision site. 
     Because the middle ear is highly innervated, repeated manipulation of the tympanic membrane is painful enough that patients, especially young children, who make up the majority of tube recipients, require general anesthesia. Such a drug therapy is costly and poses additional risks. 
     The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter. 
     SUMMARY 
     An insertion system includes a handle assembly and a nose assembly. The handle assembly includes a main body, a nose interface and an actuating element that moves from a first position to a second position. The nose assembly is removably attached to the handle assembly and having an insertion end. The nose assembly includes a nose, a positioning rod extending from the nose to a distal end, a cutting sheath surrounding a distal end of the positioning rod and including a cutting edge, an actuation member having a proximal end coupled to the actuating element when the nose assembly is attached to the handle assembly and a distal end attached to the cutting sheath, a ventilation tube located distal to the distal end of the positioning rod and proximal to the insertion end. The cutting sheath retracts from around the ventilation tube and along the positioning rod when the actuating element on the handle assembly is moved from the first position to the second position. 
     A method of maintaining an opening in a membrane of the body includes assembling the nose on the nose assembly to the nose interface on the main body of the handle assembly. The ventilation tube is loaded into the cutting sheath such that the ventilation tube is distal to the distal end of the positioning rod and proximal insertion end. The insertion end of the nose assembly is advanced into the body so that the cutting edge pierces the membrane and the ventilation tube is located across the membrane. The actuating element is rotated from a first position to a second position to retract the cutting sheath from around the ventilation tube and along the positioning rod. The insertion end is removed from the body. 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a simplified diagrammatic view of an ear. 
         FIG. 2  illustrates a perspective view of one embodiment of an insertion system in an assembled configuration. 
         FIG. 3  illustrates a perspective view of the insertion system illustrated in  FIG. 2  in a disassembled configuration. 
         FIG. 4  illustrates a perspective view of another embodiment of an insertion system in an assembled configuration. 
         FIG. 5  illustrates a perspective view of the insertion system illustrated in  FIG. 4  in a disassembled configuration. 
         FIGS. 6-7  illustrate related art ventilation tubes having specific features that coordinate with an insertion system, such as the insertion systems illustrated in  FIGS. 2-5 . 
         FIGS. 8-17  illustrate embodiments of ventilation tubes having specific features that coordinate with an insertion system, such as the insertion systems illustrated in  FIGS. 2-5 . 
         FIGS. 18-19  illustrate related art ventilation tubes having specific features that coordinate with an insertion system, such as the insertion systems illustrated in  FIGS. 2-5 . 
         FIGS. 20-36  illustrate further embodiments of ventilation tubes having specific features that coordinate with an insertion system, such as the insertion systems illustrated in  FIGS. 2-5 . 
         FIG. 37  illustrates a related art ventilation tube having specific features that coordinate with an insertion system, such as the insertion systems illustrated in  FIGS. 2 and 3 . 
         FIGS. 38-43  illustrate still further embodiments of ventilation tubes that coordinate with an insertion system, such as the insertion systems illustrated in  FIGS. 2-5 . 
         FIGS. 44-47  illustrate embodiments of ventilation tubes comprising medial and lateral flanges with various wall thicknesses. 
         FIGS. 48-49  illustrate embodiments of ventilation tubes comprising main bodies with varying wall thickness. 
         FIG. 50  illustrates an exploded view of the insertion end of the insertion system illustrated in  FIGS. 2 and 3 . 
         FIGS. 51-52  illustrate various section views of various embodiments of the insertion end illustrated in  FIG. 50 . 
         FIG. 53  illustrates an exploded view of an alternative embodiment of an insertion end. 
         FIG. 54  illustrates a section view of the insertion end illustrated in  FIG. 53 . 
         FIG. 55  illustrates a bottom view of the cutting sheath of the insertion system illustrated in  FIGS. 2 and 3 . 
         FIG. 56  illustrates a side view of the cutting sheath illustrated in  FIG. 55 . 
         FIG. 57  illustrates a bottom view of an alternative embodiment of a cutting sheath. 
         FIG. 58  illustrates a bottom view of another alternative embodiment of a cutting sheath. 
         FIGS. 59-64  illustrate different embodiments of a cutting sheath with a visual indicator or physical stop so as to provide the user with the ability to determine depth of penetration. 
         FIG. 65  illustrates an enlarged view of another embodiment of an insertion end a visual indicator or physical stop provided by a cutting sheath or other element positioned outwardly from the cutting sheath. 
         FIG. 66  illustrates a side view of one embodiment of a cutting sheath with a sensing element for detecting when the cutting sheath has made sufficient penetration. 
         FIG. 67  illustrates a bottom view of the cutting sheath illustrated in  FIG. 66 . 
         FIG. 68  illustrates another embodiment of an insertion end including a passive safety sheath located over a cutting sheath. 
         FIG. 69  illustrates a side view of the positioning rod illustrated in  FIGS. 2 and 3 . 
         FIGS. 70-73  illustrate enlarged views of various embodiments of a distal end of a positioning rod. 
         FIGS. 74-75  illustrate perspective views of various embodiments of positioning rods that include an interface for receiving an attachment of or positioning of other devices along its side. 
         FIG. 76  is an end view of the insertion end of the insertion system of  FIGS. 2 and 3  illustrating the relationship between the cutting sheath and the positioning rod. 
         FIG. 77  is a side view of an alternative embodiment of the actuation member of the insertion system illustrated in  FIGS. 2 and 3 . 
         FIG. 78  illustrates an enlarged exploded view of a nose of the nose assembly illustrated in  FIGS. 2 and 3 . 
         FIG. 79  illustrates enlarged assembled view of the nose of  FIG. 78 . 
         FIG. 80  illustrates an enlarged exploded view of a nose of the nose assembly illustrated in  FIGS. 4 and 5 . 
         FIG. 81  illustrates a partial perspective cut-away view of the handle assembly of the insertion system illustrated in  FIGS. 2 and 3 . 
         FIG. 82  illustrates a partial perspective enlarged view of the handle assembly of the insertion system illustrated in  FIGS. 4 and 5 . 
         FIG. 83  illustrates a section view of the handle assembly of the insertion system illustrated in  FIGS. 2 and 3 . 
         FIG. 84  illustrates a section view of the handle assembly of the insertion system illustrated in  FIGS. 4 and 5 . 
         FIG. 85  illustrates an enlarged perspective view of the assembled nose of the nose assembly and the rack of the handle assembly illustrated in  FIGS. 2 and 3 . 
         FIG. 86  illustrates a ventilation tube being radially loaded into the cutting sheath of the insertion system illustrated in  FIGS. 2 and 3 . 
         FIG. 87  illustrates a ventilation tube being axially loaded into the cutting sheath of the insertion system illustrated in  FIGS. 2 and 3 . 
         FIG. 88  illustrates an alternative embodiment for the loading tube illustrated in  FIG. 30 . 
         FIG. 89  illustrates an alternative embodiment for a ventilation tube for axially loading the tube into a cutting sheath. 
         FIG. 90  illustrates a flow chart describing a manual process for inserting a ventilation tube into a tympanic membrane of the body. 
         FIG. 91  illustrates a flow chart describing a semi-automatic process for inserting a ventilation tube into a tympanic membrane of the body. 
         FIG. 92  illustrates an embodiment of an insertion system including elements which facilitate the semi-automated placement of ventilation tubes as illustrated in  FIG. 91 . 
         FIG. 93  illustrates yet another embodiment of an insertion system including a removable element that can be slid onto the cutting sheath such that the cutting sheath is covered and protected. 
         FIG. 94  illustrates a section view and  FIG. 95  illustrates an enlarged view of the insertion end of the insertion system of  FIGS. 2 and 3  interfacing with a speculum-like device. 
         FIGS. 96-98  illustrate an embodiment of a speculum-like device with unique features for interfacing with the insertion system illustrated in  FIGS. 2 and 3 . 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments described herein are directed to various ventilation devices or tubes, such as ear tubes, and insertion systems or devices for inserting ventilation devices or tubes into different membranes of a body. In one particular embodiment, a ventilation tube includes a material that allows the device to remain in a deformed state during insertion into a body. After insertion through a target membrane, it is allowed to re-form its flanges or members in-situ to anchor it in place. The deformed ear tube and the insertion device that places the ventilation tube in the membrane allows for minimally invasive ventilation tube placement, which reduces the pain, cost and risks associated with conventional procedures and devices. 
       FIG. 1  illustrates a system of organs in an ear  10  of a body that enables a person to detect sound. Ear  10  is able to change sound pressure waves into a signal of nerve impulses to be processed by the brain. Ear  10  includes an outer ear  12 , a middle ear  14  and an inner ear  16 . Outer ear  12  collects sound and includes the pinna  18 , the ear canal  20  and an outer most layer of the ear drum or tympanic membrane (TM)  22 . Pinna  18  helps direct sound through ear canal  20  to TM  22 . Middle ear  14  includes an air-filled cavity  24  having an opening for the Eustachian tube  26  that is located behind TM  22 . Middle ear  14  also includes ossicles bones  28 . Inner ear  16  includes the fluid-filled cochlea  30  and the semicircular canals  32 . Cochlea  30  is the auditory portion of the inner ear, while semicircular canals  32  are attuned to both gravity and motion. The ossicles bones  28  transmit sound from the air in cavity  24  to cochlea  30 . Fluid in cochlea  30  moves in response to the vibrations coming from middle ear  14 . The motion of the fluid is converted to electrical impulses, which travel along the auditory nerve  34  to structures in the brainstem for further processing. Eustachian tube  26  couples cavity  24  of middle ear  14  to the nose and mouth of a human. In a normal state, Eustachian tube  26  is collapsed. However, Eustachian tube  26  can open and close to equalize pressure in cavity  24 . 
     An infection of the middle ear  14  can result in a buildup of fluid and increased pressure in cavity  24  causing severe pain. Children are often prone to infections of middle ear  14  because of their underdeveloped Eustachian tube  26 . A myringotomy is a surgical procedure in which a tiny incision is created in TM  22  to relieve pressure caused by the excessive buildup of fluid due to an infection of the middle ear  14 . If a patient requires a myringotomy, this generally suggests that Eustachian tube  26  is either partially or completely obstructed and is not able to perform its proper functions 
     In some cases, besides making an incision in TM  22 , a ventilation device or tube is inserted into the opening. Insertion of a ventilation or pressure equalizing (PE) device or tube can allow external ventilation of middle ear  14  for an extended period of time. However, in the confined space of ear canal  20 , especially an ear canal of a child, insertion of a ventilation device or tube can be difficult. In one example, the incision made in TM  22  is often made larger than cross-section area of the ventilation device or tube. In such an example, the device will fall out much earlier than desired. In another example, many surgical tools need to be used to insert the device, such as a blade, a funnel (to visualize TM  22 ), forceps (to deliver the device), suction and a microscope. Therefore, much time is needed to prepare for the relatively simple surgery and additional time is needed during the procedure to switch between uses of the different instruments. Although this relatively brief procedure can be performed on an outpatient basis, in general, children require a general anesthetic such that they remain co-operative during the procedure. Administering anesthetic increases the time of the procedure as well as cost. A device that can alleviate these disadvantages can greatly enhance patient comfort as well as reduce procedural time and undue injury to TM  22 , while simultaneously simplifying the procedure for physicians. 
     As discussed above, embodiments described are directed towards devices, systems and procedures for delivering a ventilation structure or tube to a membrane of a body, such as tympanic membrane  22  for treatment of a middle ear infection or otitis media. It should be realized, though, that embodiments described can be used to deliver and maintain an opening in any anatomical structure of the body whether the opening is naturally occurring or surgically created. Examples include maintaining an opening created by a tracheostomy, a cricothyrotomy and the like. In addition, embodiments are not limited to just ear ventilation, but could provide communication between any two areas in a body separated by a membrane or barrier. In addition, embodiments described can be used to deliver materials intended to communicate between two areas in a body, such as a ‘wick’, positioned through the TM to transport antibiotics from the ear canal into the middle ear. Embodiments described are also directed to the ventilation structure or tube itself. 
     While embodiments of the ventilation device or tube are illustrated as a hollow body, the device can also be a plug with no internal passageway for closing or plugging an opening. A plug can be used to block openings in a membrane, a vascular or vessel hole or create a mechanical communication between two spaces separated by a membrane, such as a membrane of a sinus cavity. The device can also be used to create communication between two lumens such as formation of vascular shunts or applied to the gastrointestinal tract and biliary system. The deployed distal members of the device may also provide better positioning of stents, in that, the larger ends can limit movement of the device/stent. For example, tracheal, bronchial, and esophageal stents are at high risk of movement from an originally deployed position. This is likely due to the symmetrical cylinder shape of the stent/device. Also, the device can be a minimally invasive way to deploy a trocar device/site. 
       FIG. 2  illustrates a perspective view of one embodiment of an insertion system  200  for inserting a ventilation device or tube into an anatomical structure or membrane of a body. In  FIG. 2 , insertion system  200  is in an assembled configuration.  FIG. 3  also illustrates a perspective view of insertion system  200 , but in a disassembled configuration.  FIG. 4  illustrates a perspective view of another embodiment of an insertion system  200 ′ in an assembled configuration.  FIG. 5  also illustrates a perspective view of insertion system  200 ′, but in a disassembled configuration. Insertion system  200  or  200 ′ includes two primary assemblies: a nose assembly  203  or  203 ′ and a handle assembly  205  or  205 ′. As illustrated in  FIG. 3 , nose assembly  203  or  203 ′ can be completely detached from handle assembly  205  or  205 ′. 
     Nose assembly  203  or  203 ′ includes a hollow cutting sheath  206  or  206 ′, a hollow positioning rod  204  or  204 ′, a nose  213  or  213 ′ and an actuation member  214  (illustrated in  FIGS. 50, 51 and 52 ) that extends from nose  213  or  213 ′ through the inside of positioning rod  204  or  204 ′ to attach to cutting sheath  206  or  206 ′. An insertion end or distal end  202  or  202 ′ of insertion system  200  or  200 ′ defines the distal end of nose assembly  203  or  203 ′ and is the end to which positioning rod  204  or  204 ′, cutting sheath  206  or  206 ′ and actuation member  214  interact to deploy a ventilation tube to a tissue or membrane of a body. In particular, cutting sheath  206  or  206 ′ surrounds a distal portion of positioning rod  204  or  204 ′ at insertion end  202  or  202 ′. Handle assembly  205  or  205 ′ defines an actuation end or proximal end  208  or  208 ′ of insertion system  200  or  200 ′. Handle assembly  208  or  208 ′ includes a handle  212  or  212 ′, an actuation mechanism (of which only a rotatable actuating element or scroll wheel  210  or  210 ′ is illustrated in  FIGS. 2, 3, 4 and 5 ) and a nose interface  217  or  217 ′ for interfacing with nose assembly  203  or  203 ′. As illustrated in  FIGS. 4 and 5 , in one embodiment, a plurality of mechanical bumps  299 ′ are located on an exterior surface of handle  212 ′ to provide a better grip to a user or clinician during use, especially a user clinician who is wearing gloves. Mechanical bumps  299 ′ can be raised portions of the material handle  212 ′, made of an overmold material with high frictional properties, include stickers or labels and the like. 
     In order for insertion system  200  or  200 ′ to function, at least a portion of a ventilation tube is deformed from its default or a rest state into a smaller constrained state. Cutting sheath  206  or  206 ′ is the component that holds the portion of the ventilation tube in the deformed state. After cutting sheath  206  or  206 ′ is advanced through the TM such that the ventilation tube is positioned correctly across the TM, cutting sheath  206  or  206 ′ is retracted while the ventilation tube is held in place by positioning rod  204  or  204 ′. 
     During cutting sheath  206  or  206 ′ retraction, the initial static friction between the ventilation tube and cutting sheath  206  or  206 ′ needs to be overcome to allow the ventilation tube to start to slide out of the sheath. The sliding friction needs to be continuously overcome to allow cutting sheath  206  or  206 ′ to be successfully retracted, leaving the ventilation tube in position across the TM. More specifically, The frictional force between the ventilation tube and cutting sheath  206  or  206 ′ needs to be sufficient enough such that the ventilation tube is retained in cutting sheath  206  or  206 ′ before cutting sheath  206  or  206 ′ is retracted, but small enough that cutting sheath  206  or  206 ′ can be retracted and be left in the TM. 
     Before discussing insertion system  200  and  200 ′ in detail, the following is a detailed discussion of ventilation tubes in general and various embodiments of ventilation tubes that can be used with insertion system  200  or  200 ′ for inserting into a tissue or membrane of the body. One way to control the frictional force is to control the surface area between the ventilation tube and cutting sheath  206  or  206 ′. As will be exemplified below, to keep frictional forces low, a majority of the length of a ventilation tube may be not in direct contact with cutting sheath  206  or  206 ′ by slightly undersizing the axial body of the tube compared to an inner lumen diameter of cutting sheath  206  or  206 ′. Therefore, the only portions of the ventilation tube that are in a deformed state are the flange or flanges. It is also possible to control the surface area between the ventilation tube and cutting sheath  206  or  206 ′ based on the geometry of the flange or flanges of the tube. The diameter of the flange or flanges can be made larger or smaller to increase or decrease contact area and therefore increase or decrease friction. Portions of the flange or flanges can be removed or added or other features that do not function as flanges can be added or removed to increase or decrease contact area. 
     Another way to control the frictional force is to control the normal force between the ventilation tube and cutting sheath  206  and  206 ′. As will be exemplified below, a thickness of the flange or flanges can be controlled. For example, a thicker, more structural flange exerts a larger outward force and increased friction. The choice of material for the ventilation tube also can impact friction forces. Tubes that resist deformation generate greater normal forces. For example, a tube material with a durometer appropriate for maintaining axial rigidity during deployment without generating excessive radial normal forces result can be chosen. The tube needs to be stiff enough that it can be pushed out of cutting sheath  206  or  206 ′ without collapsing axially, but soft enough that the flange or flanges can be compressed without generating too high of a friction force. 
     A third way to control the frictional force is to control the coefficient of friction between the ventilation tube and cutting sheath  206  and  206 ′ by altering the surface of one or both of the ventilation tube and cutting sheath  206  or  206 ′, by selecting specific materials of one or both of the ventilation tube and cutting sheath  206  or  206 ′ or introducing a surface modifying agent to one or both of the ventilation tube and cutting sheath  206  and  206 ′. For example, providing a fine texture to the inside of cutting sheath  206  or  206 ′ can reduce friction between the ventilation tube and cutting sheath  206  or  206 ′ by reducing the contact surface area on a microscopic level. Likewise, texturing one or more surfaces on the ventilation tube can have a similar effect. In another example, surface coatings or treatments can be applied to the ventilation tube or cutting sheath  206  or  206 ′ to modify their frictional properties. For example, the tube could b molded from a material is naturally lubricious or has an inherent lubricant, such as self-lubricating silicone rubber (i.e., Nusil MED1-4955). Cutting sheath  206  or  206 ′ could be coated with parylene to alter frictional properties without negatively impacting its cutting capabilities. In addition, tubes could be made from one or more materials with different properties to optimize for strength and surface properties where needed. For example the axial body could be made of a stiffer material, while the flange or flanges or other features that are to be compressed or deformed could be made of a softer material and/or of a material with a lower coefficient of friction. Further, lubricant, such as a silicone grease or oil, sterile saline or other suitable liquid can be placed on or between the tube and cutting sheath  206  or  206 ′. Still further, the tube can be given a partial “set” in the deformed position in cutting sheath  206  or  206 ′. This can be done over time or accelerated with heat. For example, a tube loaded into a sheath exhibits a certain normal force and resulting frictional resistance to deployment that can change over time as the material in the tube “relaxes” in the deformed state. This relaxation can be accelerated, for example, by exposing the tube to elevated temperatures. 
     Still further, axial compression of a ventilation tube, or other delivered object, may be desirable in certain applications. The friction between the ventilation tube and the cutting sheath can be used to axially compress the body of a tube, shortening the space between two points along it&#39;s body. For example, the distance between a medial flange and a visualization tab on a tube may be longer in its natural, relaxed state than when it is compressed inside a cutting sheath. In this embodiment, the tube would be loaded into the cutting sheath, and the cutting sheath may be retracted along the positioning rod such that the tube is compressed axially inside the cutting sheath, decreasing the distance between the medial flange and visualization tab. Additional retraction would result in no or minimal additional axial compression before restraining frictional forces would be overcome and the tube would be deployed. 
       FIGS. 6-49  illustrate ventilation or tympanostomy tubes with specific features that improve their ability to function in conjunction with insertion system  200  illustrated in  FIGS. 2 and 3  and with insertion system  200 ′ illustrated in  FIGS. 4 and 5 . In particular, FIGS.— 6 - 17  describe grommet-type ventilation tubes.  FIGS. 18-36  describe a variation of grommet-type ventilation tubes and  FIGS. 37-43  describe T-tube type ventilation devices. 
       FIGS. 6 and 7  illustrate exemplary grommet-type tubes that exist in the prior art, while  FIGS. 8-17  illustrate grommet-type tubes according to various embodiments of the disclosure.  FIG. 6  illustrates exemplary prior art grommet-type ventilation tube  315   a . Grommet tube  315   a  includes a hollow main body  382   a  having parallel flanges. In particular, grommet-type tube  315   a  includes a medial flange  384   a  that is to be located internal to the TM of a patient and a lateral flange  386   a  to be located external to the TM of a patient. As illustrated, medial flange  384   a  includes an outer diameter that is greater than an outer diameter of lateral flange  386   a . In this way, grommet-type tube  315   a  is less likely to fall out of the TM too early. 
       FIG. 7  illustrates an exemplary prior art grommet-type ventilation tube  315   b  known as a Paparella grommet tube. Grommet tube  315   b  is commercially available through many ventilation tube manufacturers including, but not limited to, Summit Medical, Inc. of St. Paul, Minn. Like tube  315   a , tube  315   b  includes a hollow main body  382   b  having a medial flange  384   b  and a lateral flange  386   b . Unlike tube  315   a , grommet tube  315   b  also includes a tab  388   b  located on lateral flange  386   b  and a notch  390   b  located on medial flange  384   b . In conventional applications, tab  388   b  is grasped with an instrument, such as a forceps, and notch  390   b  is provided to help insert medial flange  384   b  through the tissue. For use with insertion system  200 , tab  388   b  is bent substantially perpendicularly from the outer diameter of lateral flange  386   b  when loaded into cutting sheath  206  such that tab  388   b  is allowed to protrude through a slot in cutting sheath  206  for purposes of visualization, while medial flange  384   b  and lateral flange  386   b  are compressed in the cutting sheath for later deployment. 
     In the alternative,  FIGS. 8, 9 and 10  illustrate a perspective view, a side view and a section view of a ventilation tube  315   c  according to one embodiment Like tubes  315   a  and  315   b , tube  315   c  includes a hollow main body  382   c  having a medial flange  384   c , a lateral flange  386   c , a notch  390   c  and visualization tab  388   c . Rather than having a tab that extends in a lateral direction  383   c  along the outer diameter of the lateral flange and must be bent substantially perpendicular from the lateral direction in its loaded configuration as is the case with tube  315   b , visualization tab  388   c  is formed to extend from the outer diameter of the lateral flange  386   c , but in a direction substantially perpendicular to the lateral direction  383   c . In this way, visualization tab  388   c  need not be manipulated during loading to cause the tab to extend through the slot in the cutting sheath  206  because it is premade to do so. Visualization tab  388   c  includes a wider distal end than a proximal end that is coupled formed with lateral flange  386   c . In one embodiment, the width at the proximal end approximately corresponds with the width of the slot in the cutting sheath through which visualization tab  388   c  protrudes through, while the width of the distal end is greater than the width of the slot in the cutting sheath. 
     Compared to  FIGS. 8-10 , tube  315   d  and  315   e  of  FIGS. 11 and 12  illustrate that some or all of lateral flange  386   c  could be removed when the tube is formed according to alternative embodiments. Compared to  FIGS. 8-10 ,  FIG. 13  illustrates a tube  315   f  with an additional notch  391   f  on medial flange  384   c , which in  FIG. 13  is located opposite notch  390   c  according to another alternative embodiment. Removing a portion or portions of the medial or proximal flanges  384   c  or  386   c  can reduce the amount of flange material that must be compressed inside the sheath component, making it easier to load and/or deploy the ventilation tube. In addition, the location of a notch can provide a preferential location for the flange to fold during loading into a cutting sheath. Predictable folding into a cutting sheath allows for a more repeatable process for loading and for deploying, and allows for a planned ‘compressed’ state that the ventilation tube flanges will occupy while constrained within the sheath. 
     Compared to  FIGS. 8-10 ,  FIG. 14  illustrates a tube  315   g  with a medial flange  384   g  that is thinner than a standard ventilation tube, and a lateral flange  386   g  of varying thickness according to yet another alternative embodiment. It should be understood that one, both or none of the medial or lateral flanges could be thinner, or could be of varying thickness. Providing a thinner flange reduces the amount of material in the flange, allowing it to be constrained inside of a cutting sheath with a smaller inside diameter. Medial and lateral flanges of varying thickness combine the benefit of a thinner flange in reducing overall mass, while retaining strength and physical properties where needed. For example, the thicker part of the flange in  FIG. 14  is located proximal to tab  388   c  that interfaces with the slot in the cutting sheath  206 . To ensure that tab  388   v  remains positioned correctly, a slightly thicker flange support may be desirable. 
     Compared to  FIG. 14 ,  FIG. 15  illustrates a tube  315   h  with a slot interface element  393   h  located along the length of hollow main body  382   c  according to yet another alternative embodiment. Slot interface element  393   h  may provide additional interface area between the tube  315   h  and a cutting sheath to maintain registration during loading or deployment. It may also provide additional strength along the length of the hollow main body  382   c  of the tube to prevent the tube from collapsing longitudinally during deployment from the cutting sheath. 
     Compared to  FIG. 14 ,  FIG. 16  illustrates a ventilation tube with a notch  394   i  on lateral flange  386   g . A notch or plurality of notches on lateral flange could provide a material reduction to allow the notch to fold along predictable bends during insertion into the sheath component. In addition, the location of notches, or gaps in the lateral flange could allow for loading tools or accessories to pass along and through the flange at those points. A notch or notches could also allow ventilation tube  315   i  to be registered to a loading tool or accessory to aid in subsequent registration and loading into a sheath component. 
     In yet another alternative embodiment and compared to  FIGS. 7-10 ,  FIG. 17  illustrates a ventilation tube  315   j  with a tab  388   j  that is different than tab  388   b  or visualization tab  388   c  of tubes  315   b  or  315   c . Rather than having a tab that extends in a lateral direction  383   c  along the outer diameter of the lateral flange and must be bent substantially perpendicular from the lateral direction in its loaded configuration as is the case with tube  315   b  or a visualization tab  388   c  that extends from the outer diameter of the lateral flange  386   c  in a direction substantially perpendicular to the lateral direction  383   c , visualization tab  388   j  has a thickness that corresponds with the thickness of the lateral flange  386   c  and extends outward at a tangent from the outer diameter of lateral flange  386   c.    
       FIGS. 18 and 19  illustrate exemplary grommet-type tubes that exist in the prior art, while FIGS.— 20 - 33  illustrate grommet-type tubes according to various embodiments of the disclosure.  FIG. 18  illustrates exemplary prior art grommet-type ventilation tube  415   a  known as an Armstrong grommet tube that does not have parallel flanges. Grommet tube  415   a  is commercially available through many ventilation tube manufacturers including, but not limited to Summit Medical, Inc. of St. Paul, Minn. Grommet tube  415   a  includes a hollow main body  482   a  having a medial flange  484   a  that is to be located internal to the TM of a patient and a lateral flange  486   a  to be located external to the TM of a patient. As illustrated, medial flange  484   a  includes a bevel that corresponds to an angle that makes it easier to insert tube  415   a  into a TM of a patient. While presenting a beveled medial end to a TM during insertion to make it easier to insert, the lateral end of the tube should be “squared” for presenting to the positioning rod of the insertion system. Of course, it is possible that the lateral end could be “non-square” as long as the frictional force resisting deployment is low enough. 
       FIG. 19  illustrates another exemplary prior art grommet-type ventilation tube  415   b , which is the Armstrong grommet tube with a tab  488   b . Grommet tube  415   b  is also commercially available through many ventilation tube manufacturers including, but not limited to Summit Medical, Inc. of St. Paul, Minn. Like tube  415   a , tube  415   b  includes a hollow main body  482   b  having a beveled medial flange  484   b  and a lateral flange  486   b . Unlike tube  415   a , grommet tube  415   b  also includes a tab  488   b  located on lateral flange  486   b . In conventional applications, tab  488   b  is grasped with an instrument, such as a forceps. For use with insertion system  200 , tab  488   b  is bent substantially perpendicularly from the outer diameter of lateral flange  486   b  when loaded into cutting sheath  206 , such that tab  488   b  is allowed to protrude through a slot in cutting sheath  206  for purposes of visualization, while medial flange  484   b  and lateral flange  486   b  are compressed in the cutting sheath for later deployment. 
     Similar modifications to those illustrated in figures— 6 - 16  can be applied to tubes  415   a  and  415   b . For example,  FIG. 20  illustrates a ventilation tube  415   c  according to one embodiment. Like tubes  415   a  and  415   b , tube  415   c  includes a hollow main body  482   c  having a medial flange  484   c , a lateral flange  486   c  and visualization tab  488   c . Rather than having a tab that extends in a lateral direction  483   c  along the outer diameter of the lateral flange and must be bent substantially perpendicular from the lateral direction in its loaded configuration as is the case with tube  415   b , visualization tab  488   c  is formed to extend from the outer diameter of the lateral flange  486   c , but in a direction substantially perpendicular to the lateral direction  483   c . In this way, visualization tab  488   c  need not be manipulated during loading to cause tab  488   c  to extend through the slot in the cutting sheath  206  because it is premade to do so. Visualization tab  488   c  includes a wider distal end than a proximal end that is formed with lateral flange  486   c . In one embodiment, the width at the proximal end approximately corresponds with the width of the slot in the cutting sheath through which visualization tab  488   c  protrudes through, while the width of the distal end is greater than the width of the slot in the cutting sheath. 
     Compared to  FIG. 20 , tube  415   d  and  415   e  of  FIGS. 21 and 22  illustrate that some or all of lateral flange  486   c  could be removed when the tube is formed according to alternative embodiments. Compared to  FIG. 20 ,  FIG. 23  illustrates a tube  415   f  with a notch  490   f  in medial flange  484   c  and  FIG. 24  illustrates a tube  415   g  with a second notch  491   g  in medial flange  484   c , which in  FIG. 24  is located opposite notch  390   c  according to another alternative embodiment. 
     Compared to  FIG. 24 ,  FIG. 25  illustrates a tube  415   h  with a lateral flange  486   h  of varying thickness according to yet another alternative embodiment. Compared to  FIG. 24 ,  FIG. 26  illustrates a tube  415   i  with a slot interface element  493   i  located along the length of hollow main body  482   c  according to yet another alternative embodiment. Slot interface element  493   i  may provide additional interface area between the tube  415   i  and a cutting sheath to maintain registration during loading or deployment. Compared to  FIG. 26 ,  FIG. 27  illustrates a ventilation tube  415   j  with a notch  494   j  in lateral flange  486   c . A notch or plurality of notches on lateral flange could provide a material reduction to allow the notch to fold along predictable bends when located into the cutting sheath. In addition, the location of notches, or gaps in the lateral flange could allow for loading tools or accessories to pass along and through the flange at those points. A notch or notches could also allow ventilation tube  415   i  to be registered to a loading tool or accessory to aid in subsequent registration and loading into a sheath component. 
       FIG. 28  illustrates a perspective view of yet another alternative embodiment of a ventilation tube  415   k . In this embodiment, the hollow main body or lumen  482   k  of ventilation tube  415   k  extends from medial flange  484   a  and beyond visualization tab  488   c . In cases where a long hollow main body is desired, as is shown in  FIG. 28 , the lateral flange or the visual indicator  488   c  may not be located at the far lateral end of the tube so that the visual indicator can be used to determine correct placement without excessive penetration behind the TM which could damage the back wall of the inner ear. As shown, hollow main body  482   k  extends past visualization tab  488   c  to ensure that the tube does not fall inside the TM, even if the device is slightly over-inserted through the TM.  FIG. 29  illustrates a perspective view of yet another alternative embodiment of a ventilation tube  415 L. Like  FIG. 19 , tab  4881  extends in a lateral direction from the outer diameter of the lateral flange  486   c , but includes a tab having a wider distal end than a proximal end. 
       FIG. 30  illustrates a perspective view of yet another alternative embodiment of a ventilation tube  415   m . In this embodiment, like tube  415   k , the tube  415   m  includes hollow main body or lumen  482   k  that extends from medial flange  484   m  and beyond visualization tab  488   m . As shown, hollow main body  482   k  extends past the lateral flange or visualization tab  488   m  to ensure that the tube does not fall inside the TM, even if the device is inserted too far through the TM.  FIG. 31  illustrates a perspective view of yet another alternative embodiment of ventilation tube  415   n . Ventilation tube  415   n  is like ventilation tube  415   m , except, medial flange  484   n  is trimmed along edge  490   n . Trimmed edge  490   n  increases the clearance between medial flange  484   n  and visualization tab  488   m , providing more leeway on placement across the TM.  FIG. 32  illustrates a perspective view of yet another alternative embodiment of a ventilation tube  415   o . Like tube  415   n , tube  415   o  includes a trimmed medial flange  484   n  and visualization tab  488   m . However, hollow main body or lumen  482   o  extends beyond visualization tab  488   m  a shorter axial length. To compensate for the shorter axial length, an extra lateral tab  486   o , besides the use of visualization tab  488   m  as a lateral flange, substantially opposes visualization tab  488   m  to keep the tube from falling inside or behind the TM. In addition, lateral tab  486   o  can be folded back while it is loaded in the cutting sheath so that it is positioned as far away from the cutting edge of the cutting sheath as possible to ensure that it is deployed last, or as far lateral as possible, minimizing the chance of over-insertion during deployment. 
       FIG. 33  illustrates a perspective view of yet another alternative embodiment of a ventilation tube  415   p . In this embodiment, like tube  415   n , tub  415   p  includes a trimmed medial flange  484   n  and a lateral flange or visualization tab  488   m . However, the portion of hollow main body or lumen  482   p  that extends past visualization tab  488   m  is split along its axial length from visualization tab  488   m  to lateral end  48 ′ 7   p  for preventing the inner lumen from plugging with effusion. The split provides many advantages. For example, the split minimizes the axial length of the inner lumen of tube  415   p , the split provides a shorter section of small diameter inner lumen, the split helps to hold the tube from falling into the middle ear post deployment by acting as a lateral flange and the split makes it easier to unplug a tube that has become plugged. 
     In addition, while the minimum distance between the medial and lateral flanges for the tubes shown in  FIGS. 6-17  can only be increased or decreased by changing the length of the hollow main body, as illustrated in  FIGS. 34, 35 and 36 , this distance  496   q - 1 ,  496   q - 2  and  496   q - 3  can be modified for the tubes shown in FIGS.— 18 - 27  by changing the placement of either medial flange  484   q - 1 ,  484   q - 2  and  484   q - 3  or lateral flange  486   q - 1 ,  486   q - 2 , and  484   q - 3  or by removing or trimming the medial flange  484   q - 2  as illustrated in  FIG. 35  (i.e., any flange that is not positioned at a right angle to the axis of the hollow main body of a grommet-type ventilation tube). Placement of the medial flange changes the distance between the lateral and medial flanges (whether smaller or larger) to make insertion of the ventilation tube easier. Because the user must position the device across the TM using visual indicators of depth, a longer hollow main body would allow for a larger range of acceptable positioning of the tube which results in successful deployment across the TM. 
       FIG. 37  illustrates another exemplary tube style commonly referred to as a T-tube, while FIGS.— 38 - 41  illustrate T-tubes type tubes according to various embodiments of the disclosure.  FIG. 37  illustrates exemplary prior art T-tube type ventilation tube  515   a , which is commercially available through many ventilation tube manufacturers including, but not limited to Summit Medical, Inc. of St. Paul, Minn. T-tube  515   a  includes a hollow main body  582   a  having a pair of medial flanges  584   a  and  585   a  that are to be located internal to the TM (TM) of a patient. 
     FIGS.— 38 - 41  illustrate modifications similar in intended function as those shown for grommet style tubes.  FIG. 38  shows a T-tube style ventilation tube  515   b  with a visualization tab  588   b  located at and extending from lateral end  587   b  according to one embodiment. Visualization tab  588   b  is intended to interface with a slot in the cutting sheath component of insertion system  200 . In this embodiment, the visualization tab  588   b  protrudes radially from the hollow main body  582   a  of ventilation tube  515   b  (i.e., substantially perpendicular to an axial direction of the tube), but it should be understood that visualization tab  588   b  could be oriented at any angle to the axis of the hollow main body of the tube. In addition, visualization tab  588   b  may be located at the lateral end or anywhere along the length of the hollow main body of the tube. 
       FIG. 39  illustrates another embodiment where the tab intended to interface with a sheath in a sheath element of an insertion device is oriented along or parallel to the main axis of the main body of the ventilation tube. In this embodiment, visualization tab  588   c  would need to be deformed outward during or after insertion into the sheath so that it would extend radially outward to provide a visual indicator of depth or a physical stop.  FIG. 5D  illustrates another embodiment with an axially aligned visualization tab  588   c  and a radially located visualization tab  589   d . In this embodiment, the axially aligned visualization tab  588   c  could be bent or positioned through a slot in the cutting sheath to provide a physical or visual stop. The radially located visualization tab  589   d  located along hollow main body  582   a  could additionally register the tube with the slot in the cutting sheath. Furthermore, tab  589   d  could provide longitudinal strength to hollow main body  582   a  to prevent the tube from collapsing along its longitudinal axis when the cutting sheath is retracted. In  FIG. 5D , the radial tab is located along a portion of the hollow main body of the ventilation tube that would normally be located lateral to the TM, but the visualization tab  589   d  could extend along the full length of the hollow main body  582   a , along the portion normally located behind the TM, or along any other portion thereof. 
       FIG. 41  illustrates a tube  515   e  with two visualization tabs  588   c  and  588   d  shaped to interface with a slot on a cutting sheath of insertion system  200 . In instances where the pair of medial flanges are longer compared to the hollow main body of the tube, or in cases where the hollow main body of the tube itself is elongated, having two visualization tabs that extend through a slot on a cutting sheath may be desirable. For example, tube  515   e  could be inserted so that the medial visualization tab  588   d  is located just outside the TM, which would ensure that the pair of medial flanges would be located past the TM for correct deployment. The lateral visualization tab  588   b  could then be used to verify that the tube was fully deployed from the cutting sheath of insertion system  200 . In addition, a single tab or registration feature extending along the outside of a ventilation tube and intended to interface with a cutting sheath of an insertion system could be located to provide the same functionality as a number of tabs in indicating correct device positioning with the TM during insertion. 
       FIG. 42  illustrates a tube  515   f  having a lateral flange or visualization tab  588   f . Tube  515   f  is similar to tube  515   b , however, visualization tab  588   f  is not located at a lateral end  587   f  of hollow main body  582   a , but along the length of hollow main body  582   a . As shown, hollow main body  582   a  extends past visualization tab  588   f . In one embodiment, the extended length ensures that the tube does not fall inside the TM, even if the device is inserted too far through the TM.  FIG. 43  illustrates a tube  515   g . Tube  515   g  is similar to tube  515   f , however, rather than tube  515   g  having a pair of medial flanges that are curved as is shown in  FIGS. 37-42 , tube  515   g  has a pair of medial flanges  584   f  and  585   f  that are flat. Flat medial flanges  584   f  and  585   f  are one example of a geometry that provides less frictional forces inside a cutting sheath and make deployment easier. 
       FIGS. 44-47  illustrate ventilation tubes and corresponding cross sections exhibiting variations in flange thickness and hollow main body thickness.  FIG. 44  illustrates a side view of a ventilation tube  615   a  and  FIG. 45  illustrates a section view of ventilation tube  615   a . Tube  615   a  includes a hollow main body and parallel flanges that are of the same outer diameter, but one flange is thinner where it joins the main body than the other. Such a construction could allow for easier deformation and improved folding of the thinner flange during loading and retention in a cutting sheath of an insertion system. In addition,  FIGS. 44 and 45  also show a flange that has variable radial thickness (i.e., a flange that is thinner near the hollow main body of the tube and thicker near the outer radius of the flange). The thinner flange section near the hollow main body improves bending or deforming of the tube for loading into a cutting sheath, while the thicker outer edge retains sufficient physical properties to allow the flange to return to its pre-deformed shape upon deployment from the sheath. 
       FIG. 46  illustrates a side view of a ventilation tube  615   b  and  FIG. 47  illustrates a section view of ventilation tube  615   b . Tube  615   b  includes parallel flanges that are of the same outer diameter and a hollow main body there between. In  FIGS. 46 and 47 , the thickness of the hollow main body varies along the tube&#39;s axial length. Shown is a thin section of the body located near both the lateral and medial flanges which would improve the bending and deformation of the tube at those points for insertion into a sheath element. It should be noted that the thin section could be at just one end or the other, or if a flange was not fully circumferential, the thin section of the body could be limited to a portion of the circumference of the body. The ability to maintain thicker body sections while providing thinner sections allows the tube to be easily deformed for insertion into a sheath, but still include the necessary axial stiffness to maintain axial length during deployment (i.e. not compressed longitudinally when deployed from a cutting sheath). 
       FIG. 48  illustrates an end view of a ventilation tube  715  and  FIG. 49  illustrates a section view of ventilation tube  715 . Tube  715  includes a thicker portion of the hollow main body running the entire axial length of the tube. This construction allows for a tube that has structural stiffness in an axial direction while providing greater flexibility for compression and folding of the flanges for insertion into a sheath element. 
     With reference back to insertion systems  200  and  200 ′,  FIG. 50  is a partial exploded view of insertion end  202  of insertion system  200  and  FIG. 51  is an enlarged sectional view of insertion end  202  of insertion system  200 . Although  FIGS. 50 and 51  refer back to insertion system  200 , it should be understood that  FIGS. 50 and 51  also represent the same components in insertion system  200 ′. Cutting sheath  206  surrounds a distal portion of positioning rod  204  including a distal end  207  and is configured to receive a ventilation tube  215  constrained within the boundaries of cutting sheath  206 . Positioning rod  204  is a hollow body that attaches to handle  212  through nose  213 , bends along an angle  216  and, in one embodiment, includes a slot or channel  222  in the distal portion. Actuation member  214  can be made of a flexible material, such as but not limited to plastic or thin metal wire, and runs from a portion of an actuation mechanism including rotatable actuating element  210  housed within handle  212 , extends through and/or down the inside of positioning rod  204  and cutting sheath  206  and is fixedly attached to cutting sheath  206  at an attachment area  218 . In alternative embodiments, the connection between actuation member  214  and cutting sheath  206  can be a removable connection. 
     Cutting sheath  206  includes an aperture  220  that extends entirely through a thickness  235  of a wall of cutting sheath  206 . Aperture  220  allows actuation member  214  to transition from an area internal to cutting sheath  206  to an area external to cutting sheath  206 . Aperture  220  also defines attachment area  218  by providing access to form a joint between actuation member  214  and cutting sheath  206 , making it possible to weld or otherwise bond actuation member  214  to cutting sheath  206 . In one embodiment, a distal end  221  of actuation member  214  is welded to aperture  220  to fixedly attach it to cutting sheath  206 . For example, distal end  221  of actuation member  214  can be plug welded to aperture  220 . In this embodiment, slot  224 , which allows for the protrusion of a tab or visualization tab (such as those visualization tabs discussed in  FIGS. 3-7 ), can also be used to allow access to the plug weld that attaches actuation member  214  to aperture  220  in cutting sheath  206 . 
       FIG. 52  is similar to  FIG. 51 , however, rather than ventilation tube  215  being loaded into cutting sheath  206 , in  FIG. 52 , ventilation tube  415   o  is loaded into cutting sheath  206 . In  FIG. 52 , lateral tab  486   o  is folded back and visualization tab  488   m  protrudes through slot  488   m . Since tube  415   o  includes a medial flange  484   m  that is tapered like the beveled distal edge  209  of cutting sheath  206 , tube  415   o  can be placed closer to distal edge  209  than tube  215 , which minimizes the insertion depth required to deploy behind the TM. Minimizing insertion depth is better in situations where the TM is retracted. 
     In another embodiment and as illustrated in  FIG. 53 , which is a partial exploded view of an alternative insertion end  302  of insertion system  200 , and in  FIG. 54 , which is an enlarged sectional view of insertion end  302 , it is possible to attach an actuation member  314  to a cutting sheath  306  at an attachment area  318  by allowing access to the attachment area utilizing a slot  324  that extends entirely through the thickness  235  of a wall of cutting sheath  306  that is located opposite of where aperture  220  in cutting sheath  206  is located. Slot  324  spans a length from a distal end or cutting edge  309  of cutting sheath  306  to a termination area and can be used to pass appropriate instruments through the wall of cutting sheath  306  for joining actuation member  314  to an internal wall of cutting sheath  306 . For example, actuation member  314  can be joined to cutting sheath  306  by welding or otherwise bonding. In this embodiment, an aperture, such as aperture  220  of insertion end  202 , is not needed. Both insertion end  202  and  302  already include slot  224  or  324  to allow for the protrusion of a tab or visualization tab (such as those visualization tabs discussed in  FIGS. 6-49 ) of ventilation tube  215  or  315 . In still another embodiment, a different slot could extend entirely through the thickness of a wall of cutting sheath  306 , but spans a length from a proximal end  311  to a terminating area of cutting sheath  306  for this same purpose. 
     With reference back to  FIGS. 50-52 , in addition, actuation member  214  can travel in slot or channel  222  of positioning rod  204 . In one embodiment, slot or channel  222  intersects with distal end  207 , extends entirely through a thickness  237  of a wall of positioning rod  204  and includes a length  223  that spans from distal end  207  of positioning rod  204  to a terminating area that is surrounded or covered by cutting sheath  206 . Ensuring slot  222  is covered by cutting sheath  206  is important in preventing loss of suction when insertion system undergoes a suction functionality. Slot or channel  222  registers cutting sheath  206  to positioning rod  204 . In an alternative embodiment, cutting sheath  206  could extend a larger distance from distal end  207  of positioning rod  204  than that which is illustrated in  FIG. 9  such that the entire range of motion of actuation member  214  occurs at a point beyond distal end  207  of positioning rod, such that slot or channel  222  is not required. 
     In still another embodiment and in instances where actuation member  214  does not interface with a slot or channel  222  in positioning rod  204  to provide a means of registration for cutting sheath  206 , the geometry of actuation member  214  could provide a means of registration. For example, a round steel wire would limit the degree of rotation that cutting sheath  206  can achieve. In another example, a flat wire or the use of two or more actuation members attached at different locations on cutting sheath  206  could also be employed to reduce the achievable angle of rotation between cutting sheath  206  and positioning rod  204 . Because of the bend that actuation member  214  takes as it travels inside the bend area of positioning rod  204 , the torsional rigidity of a flat actuation member  214  could be enhanced further to minimize angular displacement of cutting sheath  206  in relation to positioning rod  204 . The geometry of actuation member  214  will be further discussed below. 
     As illustrated in  FIGS. 51 and 52 , actuation member  214  is attached to aperture  220  of cutting sheath  206  a sufficient distance from a distal end  209  of cutting sheath  206  so as not to interfere with the placement of tube  215  distal to joint  218 . In particular,  FIGS. 50-52  show actuation member  214  attached closer to distal end or cutting edge  209  of cutting sheath  206  than to proximal end  211  of cutting sheath  206 . In embodiments where actuation member  214  travels in slot or channel  222  in positioning rod  204 , the location where actuation member  214  is attached to aperture  220  minimizes the length required of channel  222  in positioning rod  204  and improves manufacturability. It should be realized, however, the attachment between the actuation member  214  and cutting sheath  206  can be located anywhere along the internal lumen or wall of cutting sheath  206 . 
       FIG. 55  illustrates a bottom view of cutting sheath  206  and  FIG. 56  illustrates a side view of cutting sheath  206  according to one embodiment.  FIGS. 55 and 56  illustrate cutting sheath  206  with a sharpened, beveled distal end or cutting edge  209  and a slot  224  extending from the sharpened, beveled distal end or cutting edge  209  to a terminating end  225 . In one embodiment, the overall length  226  of beveled end  209  is minimized, as this portion must extend past the tympanic membrane into the constrained space of the middle ear during ventilation tube placement and not interfere with the highly sensitive bones and organs in the middle ear. To minimize length  226 , beveled end  209  includes a primary bevel angle  228  that is relative to a wall  230  of cutting sheath  206 . For example, primary bevel angle  228  can range between approximately 30 degrees and 40 degrees. 
     Additional grinding steps can be taken to enhance the cutting ability, or sharpness, of beveled distal end or cutting edge  209 . As illustrated in  FIGS. 55 and 56 , at least one set of lancet grinds are used to produce lancet edges  232  and  233 . The lancet grinding step is capable of removing additional overall length from the beveled area, which further shortens the portion of the cutting sheath that must extend into the middle ear during ventilation tube placement. In one exemplary embodiment, beveled length  226  of a 15 gauge cutting sheath (outer diameter of 0.072 in. or 1.829 mm) with a 30 degree primary bevel in combination with secondary lancet grinds can be less than 0.10 in. or 2.54 mm. In another exemplary embodiment, beveled length  226  of a 15 gauge cutting sheath (outer diameter of 0.072 in. or 1.83 mm) with a 40 degree primary bevel in combination with secondary lancet grinds can be less than 0.075 in. or 1.905 mm. 
     In cases where the TM is already perforated or an incision is made with another instrument or when there is insufficient room behind the TM (i.e., severe TM retraction), cutting sheath  206  can include a minimal bevel or no bevel. For example, cutting sheath  206  could be made with an approximate 70 degree bevel and can be combined with a tube having little or no bevel on the medial flange. 
     A lancet grind, or comparable sharpening procedure which produces cutting edges located along the outer diameter of the cutting sheath are preferred when a ventilation tube is loaded into the cutting sheath  206  by inserting it axially from the distal end or cutting edge  209  of the cutting sheath  206 . Sharp edges on the inner diameter of the cutting sheath  206 , such as those achieved with a back-grind style of sharpening, tend to catch or cut the tube during such a loading process. Methods of loading a ventilation tube into cutting sheath  206  will be discussed in detail below. 
     Cutting sheath  206  can be made of thin walled stainless steel tubing having a wall thickness  235 . However, other thin-walled metallic tubing can also be suitable. For example, 15 gauge thin-walled tubing (having 0.006 in. or 0.153 mm thick wall) provides sufficient rigidity to constrain ventilation tube  215  in a compressed configuration. In addition, wall thickness  235  provides sufficient material to sharpen into a cutting edge  209 . 
     One important feature of cutting sheath  206  (and also positioning rod  204 ) is the surface finish. The insertion system  200  can be operated under direct visualization by the user which requires sufficient lighting. In one embodiment, when used with an otoscope, operating microscope, or fiber optic scope, a non-reflective surface finish can reduce the glare off cutting sheath  206  and positioning rod  204 , which would hinder visualization. A non-glare surface finish can be achieved by abrasive blasting of the parts, surface passivation, oxidation, or other suitable surface treatment, which reduce or eliminate the reflective properties of materials of cutting sheath  206  and positioning rod  204 . In another embodiment, the inner diameter of cutting sheath  206  and/or the outer diameter of positioning rod  204  could be treated with a lubricious coating, such as PTFE, to reduce the friction between the two sliding surfaces during sheath retraction while also providing a non-glare surface. 
     The slot  224  illustrated in  FIGS. 9 and 12  allows a tab or visualization tab  288  of ventilation tube  215  to be visible, or for a tab or visualization tab  288  of ventilation tube  215  to extend outward through cutting sheath  206  to provide a physical or visual indication of tube  215  location for proper placement through the TM. As illustrated in  FIGS. 7 and 8 , slot  224  extends from distal end or cutting edge  209  to terminating end  225  and is substantially straight. 
     However, slot  224  is not limited to the configuration illustrated in  FIG. 55 .  FIG. 57  illustrates a bottom view of another embodiment of a cutting sheath  406 , slot  424  can have a spiral twist, which could be used to impart a spin on a ventilation tube, such as ventilation tube  215 , to improve deployment across the TM. A slot  424  having a twist, or other non-straight geometry could also be used to position a tab on the ventilation tube, such as visualization tab  288  of ventilation tube  215 , closer to the longest edge of the cutting sheath (i.e., opposite where the slot  424  intersects with distal end or cutting edge  409 ) to allow a user to more easily visualize both the tab on the ventilation tube and the longest edge of cutting edge  209  during use. Slot  424  can be formed using a helix that has a pitch ranging between 0.5 inches (12.7 mm) and 1.5 inches (35.1 mm). However, slot  424  can also be a simple curve. 
       FIG. 57  also illustrates cutting sheath  406  with an unsharpened cutting edge or distal end  409 , which allows an insertion system, to be used to insert a ventilation tube into a pre-existing incision in the TM. A primary bevel of between approximately 40 and 60 degrees minimizes the length of cutting sheath  406  that must be inserted into the middle ear to properly position the ventilation tube across the TM. Since cutting sheath  406  doesn&#39;t require sharpening, cutting sheath  406  could be manufactured from plastic, such as PEEK, acrylic, poliamide, or suitable alternatives, and could be clear or translucent to allow the user to visualize the ventilation tube loaded in cutting sheath  406 . In addition, a light source internal to the positioning rod, for example a fiber optic light source, could be used to illuminate a clear sheath from the inside, thus allowing a tertiary means of determining tube location within the sheath to aid in placement in the TM at the correct depth. 
       FIG. 58  illustrates a bottom view of yet another embodiment of a cutting sheath  506  with a modified geometry where slot  524  meets sharpened distal end or cutting edge  509 . This modified geometry can be achieved during the forming of slot  524 , or during the sharpening process. Beveling, or softening the corners  536  where slot  524  meets the sharpened beveled face  538  of cutting sheath  506  solves two problems. First, it reduces the chances of tearing the TM or accidental ‘coring’ out of a section of the TM and second, it improves the loadability of ventilation tubes if those tubes are inserted into the distal end  509  of the tube. Sharp corners or points created by slot  524  that is cut straight into the beveled end of the sheath can catch, cut, or tear silicone ventilation tubes during loading if not beveled or softened. 
       FIGS. 59-64  illustrate different embodiments of a cutting sheath with a visual indicator or physical stop so as to provide the user with the ability to determine depth of penetration through the TM relative to the bevel located on the distal end of the cutting sheath. In  FIGS. 59 and 60  (where  FIG. 59  illustrates a perspective view and  FIG. 60  illustrates a side view), a visual indicator  1445  extends outward from cutting sheath  1406  approximately 180 degrees from the top of cutting sheath  1406  and opposite a slot (not illustrated), which is located at a bottom of cutting sheath  1406 . In addition, visual indicator  1445  is positioned at the substantially same distance as the distance of the proximal end of the beveled portion (i.e., where the bevel portion begins) of cutting sheath  1406 . Visual indicator  1445  allows a user to visually determine the degree of bevel penetration through the TM without being able to see the actual beveled portion of cutting sheath  1406 . Visual indicator  1445  could also provide tactile feedback that the correct penetration depth has been achieved by stopping further advancement of the sheath manually through the TM. In  FIGS. 61 and 62  (where  FIG. 61  illustrates a perspective view and  FIG. 62  illustrates a side view), a visual indicator  1545 , which encompasses all or a portion of the outer circumference of cutting sheath  1506  and which is located such that visual or physical proximity to the TM indicates that a correct depth of penetration has been achieved such that the entire beveled portion of the sheath has penetrated the TM.  FIGS. 63 and 64  (where  FIG. 63  illustrates a perspective view and  FIG. 64  illustrates a side view) illustrates visual marker bands  1645  that may span all or a portion of the circumference of cutting sheath  1606  such that the user can visually determine the locations of the beveled portion of the sheath or the proximal end of the ventilation tube, or both, from any viewing angle along the positioning rod and sheath. In one embodiment, two visual marker bands can be used to provide a range of acceptable TM locations (e.g., a max/min type indicator). Still further, the cutting sheath, the positioning rod or both can be designed or constructed from materials that have echogenic properties, making it easier to visualize their location using ultrasound in cases where visualization by physical means is not feasible or is not sufficient. 
       FIG. 65  illustrates an enlarged view of an insertion end  1702  including one embodiment of a visual indicator or physical stop  1745  provided by a cutting sheath or other element  1751  (as is illustrated in  FIG. 65 ) positioned on the outside or over cutting sheath  1706 . As shown, cutting sheath  1706  attaches to positioning rod  1704  (shown in phantom) such that the distal end of element  1751  and visual indicator  1745  are located at the same location as the proximal end of the beveled portion of cutting sheath  1706 . In the embodiment, element  1751  is a circumferential sheath of which a portion is cut away to maintain visibility of visual indicator  1745  and of a tab  1788  on ventilation tube  1715 , which extends through the slot in cutting sheath  1706 . Additionally, the attachment point of the circumferential sheath  1751  to cutting sheath  1706  is positioned such that the necessary coaxial motion of cutting sheath along positioning rod  1704  is not impeded by circumferential sheath  1751 . Circumferential sheath  1751  could also extend over the complete length of positioning rod  1704  and be attached to the handle assembly or nose of the nose assembly. The same functionality as the functionality of circumferential sheath  1751  could be achieved with other elements, such as wires or partial sheaths which would extend along the sheath element to the beginning of the beveled portion of the cutting sheath. 
       FIG. 66  illustrates a side view and  FIG. 67  illustrates a bottom view of cutting sheath  1806  with a sensing element  1853  for detecting when the cutting sheath has penetrated sufficiently through the TM to allow for tube deployment. Inserting cutting sheath  1806  through the TM far enough so that the lateral flange of the ventilation tube is past the TM at the shallowest point of penetration ensures successful tube placement. Because of the bevel on cutting sheath  1806 , a heel  1855  of the bevel will be the point where minimum penetration occurs, and as such, sensing when this point or a point just past this on the cutting sheath is in contact with the TM would allow the user to detect correct depth of penetration for tube deployment. A mechanical sensor to detect the physical resistance created by direct contact with the TM, or an electrical sensor to detect a change in electrical resistance via contact with the TM can be employed. It should be understood that any sensing means capable of detecting contact or proximity could be used. Upon detection of a correct depth of penetration, the insertion device could generate a signal, such as an audible tone, to indicate to the user that tube deployment can be performed. In another embodiment, the insertion device may detect a correct depth of penetration through the TM and automatically retract the cutting sheath thereby deploying the tube and limiting an further penetration into the middle ear. In this embodiment, the user manually advances the device through the TM until the sheath retracts automatically, and then applies suction if necessary or removes the device from the ear canal. 
       FIG. 68  illustrates a side view of another embodiment of an insertion end  602 . In  FIG. 68 , a passive safety sheath  637  is located over the cutting sheath  606  (shown in phantom). Safety sheath  637  can be held in place by friction, and manually removed by the user immediately before use. This safety sheath  637  protects the cutting edge  609  during shipping, and protects the clinician from inadvertent needle sticks or cuts prior to use. Alternatively, safety sheath  637  can be manually retracted by the user immediately before use, exposing the cutting edge  609  but remaining in place around positioning rod  604 . After deploying a ventilation tube across the TM, safety sheath  637  could then be moved back into its original position around cutting sheath  606 , again protecting users from inadvertent needle sticks. 
       FIG. 69  illustrates a side view of positioning rod  204 . Positioning rod  204  is a continuous hollow body including a bend  246  having an angle  216  that divides positioning rod  204  into a first leg  247  and a second leg  249 . First leg  247  is greater in length than second leg  249  and includes distal end  207 , which is configured to abut against a ventilation tube when loaded in insertion system  200  and when being deployed. A proximal end  248  of second leg  249  engages with nose  213  ( FIG. 2 ) of insertion system  200 . The length of the short leg  249  extends through nose piece  250  and between approximately 0.5 and 1.5 inches (i.e., 12.7 and 38.1 mm). The function of short leg  249  is to move longer leg  247  sufficiently far enough away from where nose  213  connects to handle  212  ( FIG. 2 ) to allow the user to maintain sight lines straight down leg  247 . The shorter leg  249  ensures that the user does not block these sight lines with their fingers while grasping the front of handle  212 . The length of longer leg  247  is between approximately 50 and 100 mm. More particularly, leg  247  is approximately 60-65 mm. This length is sufficient to allow cutting sheath  206  to reach deep enough into the ear canal and the middle ear for a ventilation tube to be positioned and deployed across the TM. The radius of the bend  246  in positioning rod  204  can range between approximately 0.25 and 2 inches (i.e., 6.35 and 50.8 mm). More particularly, the radius of bend  246  can be between approximately 0.4 and 0.8 inches (i.e., 10.16 and 20.32 mm). The bend  246  in positioning rod  204  should be minimized so that the radius portion does not interfere with the a speculum (which will be discussed in detail below) or other interfacing accessories, while being kept large enough such that it allows the sliding of the actuation member  214  along its inner lumen without imposing excessive frictional restraining forces. In a spring-loaded design, where a spring is chosen to set the resistive force, a large radius for the positioning rod to minimize resistance could be used. 
       FIGS. 70-73  illustrate enlarged views of various embodiments of a distal end of a positioning rod.  FIG. 70  illustrates an enlarged view of distal end  207  of positioning rod  204 . Positioning rod  204  includes a straight slot or channel  222  formed into positioning rod  204  and intersecting with distal end  207  and extending to a terminating area  239 . As previously described, channel  222  provides a passage for actuation member  214  to transition from the inside of positioning rod  204  to an attachment point on the corresponding cutting sheath  206 . In addition, a length  223  of channel  222  provides a range of motion for actuation member  214 , and can limit the maximum range of motion of cutting sheath  206 . Furthermore, channel  222  registers cutting sheath  206  to positioning rod  204 . In particular, the angular orientation of cutting sheath  206  is registered relative to positioning rod  204 . 
       FIG. 71  is an enlarged view of an alternative embodiment of a distal end of a positioning rod. Like channel  222 , a channel  722  formed in a positioning rod  704  is straight. However, rather than channel  722  intersecting with distal end  207 , as is the case in  FIG. 70 , channel  722  extends from a distal area  741  that does not intersect with distal end  707  to a terminating area  739 . The embodiment illustrated in  FIG. 71  provides a full circular contact area at the end of positioning rod  704  for positioning against a ventilation tube when a cutting sheath is being retracted during deployment of a ventilation tube. 
       FIG. 72  is an enlarged view of another alternative embodiment of a distal end of a positioning rod.  FIG. 72  illustrates an embodiment where channel  822  includes a straight portion  842  and a j-shaped portion  843 . Like channel  222 , straight portion  842  of channel  822  intersects with distal end  807  and extends to a terminating area  839 . J-shaped portion  843 , however, extends as an arcuate slot from terminating area  839  to arcuate end  844 . J-shaped portion  843  is configured to capture the actuation member after a ventilation tube is deployed, and preventing the cutting sheath from being displaced forward again towards the TM. In cases where the cutting sheath is retracted sufficiently such that the cutting edge is positioned directly over positioning rod  804  and proximal to distal end  807 , positioning rod  804  acts as a safety mechanism which protects the cutting edge of the cutting sheath to prevent accidental needle sticks. Additionally, because positioning rod  804  cannot be returned to a pre-use state, the embodiment illustrated in  FIG. 72  can also prevent the re-use of an insertion end when the insertion end is intended to be a single-use device. While a J-shaped portion  843  of channel  822  is shown, other geometries which achieve the same functionality are also considered. 
     For example,  FIG. 73  illustrates an enlarged view of an embodiment where channel  922  of a positioning rod  904  intersects with distal end  907  of positioning rod  904  and extending to a terminating area  939 . Unlike channels  222 ,  722  and  822 , channel  922  includes a helical or curved pathway. The helical or curved pathway of channel  922  aids in inserting a ventilation tube into an insertion end by slightly rotating the cutting sheath as it is retracted along positioning rod  904 . A helical pathway can be formed using a helix that has a pitch between approximately 0.5 inches (12.7 mm) and 1.5 inches (38.7 mm). It should be understood that any combination of the preceding elements described in  FIGS. 70-73  regarding channels in a positioning rod can be used. 
       FIGS. 74-75  illustrate perspective views of various embodiments of positioning rods that include an interface for receiving an attachment of or positioning of other devices alongside it such that the user can move and position an attached device and the positioning rod with a single hand. The embodiment illustrated in  FIG. 74  shows a positioning rod  1004  having a clip  1052  located on the outer surface of the longer leg  1047 . For example, clip  1052  can receive a fiber optic scope, a fiber optic light source, drug delivery tubes, devices, or an atomizer or other type of peripheral attachment for enhancing the capabilities of the insertion system. The embodiment illustrated in  FIG. 75  shows a positioning rod  1104  having a protuberance  1152  located on the outer surface of the longer leg  1147 . For example, protuberance  1153  can interface with a speculum (which will be discussed in detail below) or other interfacing accessories. 
       FIG. 76  illustrates an end view of insertion end  202  (with nose  213  removed) illustrating the relationship between cutting sheath  206  and positioning rod  204  in a first position or a position A. As illustrated in  FIGS. 50-52 and 55-56  cutting sheath  206  is beveled and therefore has one side that is longer in axial length than the other. In addition, slot  224  is cut along one side of cutting sheath  206 . In one embodiment, slot  224  is formed along the shorter axial length side rather than the longer axial length side of cutting sheath  206 . Because of these features, cutting sheath  206  can be oriented in different angular relationships to the bend  246  in positioning rod  204 . In one embodiment, the long edge, or the leading point of cutting sheath  206  is located along the top of bend  246  and slot  224  is located along the bottom of bend  246  as shown in  FIG. 76 . However, the long edge and therefore slot  224  on the sheath could be located at various angular relations to the bend  246  in positioning rod  204  to improve visualization under different scenarios. For example, the long edge of cutting sheath  206  could be positioned approximately 180 degrees from the top of the bend  246  of positioning rod  204  as indicated by a second position or a position B, or at any angle in between, such as approximately 45 degrees as indicated by a third position or a position C or approximately 90 degrees as indicated by a fourth position or a position D. 
     As previously discussed and with reference back to  FIG. 50 , actuation member  214  of insertion system  200  passes through channel  222  in positioning rod  204  to attach to cutting sheath  206 . In  FIG. 50 , actuation member can consist of a round, stainless steel wire with a spring temper or a soft temper that has a diameter of about 0.014 inches or 0.3556 mm. A round cross section allows actuation member  214  to interface with a round plug hole in cutting sheath  206  for ease of manufacturing and for making an attachment such as a weld or a braze between cutting sheath  206  and actuation member  214 . The spring temper helps prevent bends from setting during handling, manufacturing and assembly. In the alternative, a smaller diameter actuation member can also be used, such as a diameter of about 0.009 inches or 0.2286 mm, to reduce friction inside the positioning rod. By keeping actuation member  214  consistently straight, or with a known bend profile, the frictional force of actuation member  214  contacting the internal lumen of positioning rod  204  is kept consistent and provides for a consistent degree of resistance during cutting sheath  206  retraction. Actuation member  214  can also include a lubricious coating, such as PTFE, to minimize the frictional force of actuation member  214  sliding inside positioning rod  204 . In an alternative embodiment, actuation member  214  can consist of flat wire. Flat wire can provide a greater surface area and potentially improved interface geometry where actuation member  214  attaches to cutting sheath  206  or to actuator mechanism  210  in handle  212 . 
       FIG. 77  is a side view of an actuation member  1214  that illustrates alternative embodiments to actuation member  214  illustrated in  FIG. 50 . In one embodiment, actuation member  1214  includes one or more bends  1254  along its length which can increase or decrease the frictional force that actuation member  1214  experiences sliding along the internal lumen of a positioning rod during cutting sheath retraction. Bend  1254   a  illustrates a bend in a shape closely approximating the bend in a positioning rod, which eliminates most of the friction encountered during initial retraction of the cutting sheath, allowing for an easier start to the retraction process. Bends  1254   b, c  and  d  show actuation member  1214  with one or more bends intended to increase the frictional force between actuation member  1214  and a positioning rod. Increasing the force between actuation member  1214  and a positioning rod can be useful for holding the cutting sheath in the retracted position after a ventilation tube has been deployed and preventing unwanted sheath retraction during shipping and handling prior to use. Bends  1254   a, b  and  c  can also provide repeatable resistive force during the entire cutting sheath retraction process, and prevent inadvertent ‘jumping’ of the ventilation tube out of the cutting sheath when the ventilation tube is partially or fully deployed. If the frictional force of the ventilation tube against the inner lumen of the cutting sheath is the governing resistance to sheath retraction, the resisting force will change as the ventilation tube is deployed and the contact surface area is reduced, and may change in a stepwise function as flanges on the ventilation tube are deployed. Using the frictional resistance to motion of the actuation member can moderate this. 
     It should be noted that in another alternative embodiment, an actuation member could be routed completely outside of the positioning rod rather than partially inside the positioning rod and therefore positioning rod  204  need not be hollow. In such an embodiment, the actuation member exits the handle, such as handle  212 , of the insertion system, such as insertion system  200 , and travels along the outside of the positioning rod and attaches to a proximal end of the cutting sheath or anywhere along the length of the cutting sheath. Guide tubes or tabs located along the outer diameter of the positioning rod could be used to route and constrain the actuation member. In one embodiment, the actuation member could pass through an aperture or slot in the cutting sheath and protrude into the inner lumen of the positioning rod to thus allow the actuation member to act as a registration mechanism to register the sheath to a slot or aperture located on the positioning rod. 
     The attachment between an actuation member and a cutting sheath does not need to be permanent. In such an embodiment, the actuation member may include a shorter bent portion on its end that engages reversibly with an aperture in the sheath. A larger bend or ‘bow’ in the actuation member ensures that the shorter bent portion remains pushed against the inner diameter of the cutting sheath such that at least a portion of the bent section remains engaged with the cutting sheath aperture. This embodiment allows the user to push the actuation member back into or out of the aperture on the cutting sheath, making the cutting sheath removable and/or replaceable. In instances where a bilateral ventilation tube placement is warranted, two cutting sheathes with pre-loaded ventilation tubes could be provided, and the clinician could attach them to a single insertion handle to reduce waste. 
     Besides nose assembly  203  including cutting sheath  206 , positioning rod  204  and actuation member  214 , nose assembly  203  also includes nose  213 , which is illustrated in an enlarged exploded view in  FIG. 78  and in an enlarged assembled view in  FIG. 79 . In regards to insertion system  200 ′,  FIG. 80  illustrates an enlarged exploded view of nose  213 ′. Nose  213  or  213 ′ includes an actuating mechanism interface component or pull  256  or  256 ′, a suction interface component or drain  258  and a nose piece  260 . In regards to the insertion system  200  embodiment, drain  258  and nose piece  260  are two separate components. In regards to the insertion system  200 ′ embodiment, drain  258  and nose piece  260  are integral and labeled as drain-nose piece  260 ′. In other embodiments, drain  258  and nose piece  260  can be overmolded directly onto positioning rod  204  to ensure correct orientation and sufficient bond. Regardless, the use of a suitable high viscosity lubricant, such as silicone grease, can be used between pull  256 ′ and drain-nose piece  260 ′ to eliminate gaps which can cause suction loss without negatively impacting the friction between those parts. 
     From positioning rod  204  (not illustrated in  FIG. 78 or 79 ), actuation member  214  (illustrated in  FIG. 78 ) attaches to actuating mechanism interface or pull  256  or  256 ′ along central axis  261  or  261 ′ through nose piece  260  and suction interface component or drain  258  or drain-nose piece  260 ′. In this embodiment, a fastener  259 , such as a threaded set screw ( FIGS. 78 and 79 ), can be used to hold actuating member  214  against an internal face of pull  256  or  256 ′. In  FIGS. 78 and 79 , the threaded set screw is advanced through pull  256  in a direction substantially perpendicular to central axis  261  and tightened down In other embodiments, such as the embodiment illustrated in  FIG. 80 , actuating member  214  can be held against internal face of pull  256  or  256 &#39;s using an adhesive and then trimmed off. Eliminating a hole in pull  256  or  256 ′ for receiving a fastener or other mechanical fastener would ultimately prevent suction loss. However, assembling actuating member  214  to pull  256  or  256 ′ becomes more difficult. To eliminate the hole and in one embodiment, a mechanical gripping feature, for example a one-way cam gripper, could be over-molded into pull  256  or  256 ′ such that actuating member  214  is advanced through to the correct position during assembly and automatically locks in place. 
     As illustrated in  FIGS. 78 and 80 , an aperture in the distal end of pull  256  and  256 ′ allows actuating member or wire  214  to pass through. In  FIG. 80 , the aperture is smaller than the aperture in  FIG. 78 . A smaller hole prevents suction loss when insertion system  200 ′ undergoes a suction functionality. Further, actuating member or wire  214  is mechanically sealed in the aperture with, for example, adhesive, to prevent even further suction loss when insertion system  200 ′ undergoes a suction functionality. Positioning rod  204  (again not illustrated in  FIG. 78 or 79 ) attaches to suction interface component or drain  258  or drain-nose piece  260 ′ along central axis  261  or  261 ′ through nose piece  260 . In particular, proximal end  248  ( FIG. 69 ) of positioning rod  204  traverses only a partial length of drain  258  or drain-nose piece  260 ′. 
     Drain  258  or drain-nose piece  260 ′ includes one or more suction apertures  264  or  264 ′ (of which only one is illustrated in  FIGS. 78 and 79  and of which there is only a single suction aperture in  FIG. 80 ). In the embodiments illustrated in  FIGS. 78 and 80 , suction apertures  264  or  264 ′ are square in shape. However, any shape is possible. Drain  258  or drain-nose piece  260 ′ may also include a suction block to redirect fluid traveling along axis  261  or  261 ′ through suction apertures  264  or  264 ′ and into a fluid channel in the main body of the handle assembly  205  or  205 ′. In  FIG. 78 , fastener  259  or an adhesive fastener not only functions as a device for fastening actuation member  214  in place, but also acts as the suction block. In another embodiment, though not illustrated, a suction block can include a thin polymer washer with a small hole or slit cut through it to allow the actuation member  214  to pass through, but still allow actuation member  214  to closely conform to drain  258 , thus blocking off any suction losses. In one embodiment, a suction block includes a polyurethane rubber washer with a radial slit extending halfway across the circular face. The physical properties of the suction block, along with the geometry, can be modified to increase or decrease the frictional resistance the actuating member  214  experiences passing through it. Similar to the bends that can be made in actuation member  214  to increase or decrease drag inside positioning rod  204 , the aperture size in the suction block, its frictional properties, and its thickness can all be changed to increase or decrease drag on the actuation member  214 . 
     Nose piece  260  or drain-nose piece  260 ′ includes a tab  262  or  262 ′ which interfaces or engages with a stop component  296  or  296 ′ on the handle assembly  205  or  205 ′. Tab  262  or  262 ′ provides a visual as well as functional means of registering nose assembly  203  or  203 ′ with handle assembly  205  or  205 ′ to achieve desired positioning relative to each other as well as to allow nose assembly  203  or  203 ′ and handle assembly  205  or  205 ′ to assemble or disassemble (connect or disconnect). Details regarding the connection between nose assembly  203  or  203 ′ and handle assembly  205  or  205 ′ will be discussed in detail below. 
       FIG. 81  illustrates a partial perspective cut-away view of handle assembly  205  of insertion system  200  and  FIG. 83  illustrates a section view of main body  263  of handle assembly  205  of insertion system  200 . Handle assembly  205  includes main body  263 , nose interface  217  for interfacing with nose assembly  203 , a rotatable actuating element or scroll wheel  210 , a rack  267  and one or more drive gears  268  coupling the rotatable actuating element or scroll wheel  210  to rack  267 . 
     As illustrated in  FIG. 83 , main body  263  includes a primary fluid channel  270 , a secondary fluid channel  271  and one or more suction weep holes  272 . The proximal end of main body  263  of handle assembly  205  includes an area for receiving a fitting for coupling main body  263  to a source of negative pressure. For example,  FIGS. 2 and 3 , illustrate the distal end of handle assembly  205  as including a barbed fitting  273 . 
     Suction, as provided by the suction source, passes through the primary and secondary fluid channels  270  and  271  inside main body  263  of handle assembly  205 . Primary fluid channel  270  is in fluid communication through apertures  264  in drain  258  and down the positioning rod  204  to cutting edge  209  of cutting sheath  206 . Secondary fluid channel  271  branches off primary fluid channel  270  and is in communication with the one more weep holes  272 . Weep holes  272  provide the control for delivering suction to distal end  207  ( FIGS. 50 and 65 ) of the positioning rod  204 . In one embodiment, a plug, adhesive patch, or other suitable component can be used to block off one of the two weep holes. The user is able to cover the remaining weep hole as desired to direct the application of negative pressure to distal end  207  of positioning rod  204  or insertion end  202 . Handle assembly  205  can be provided with a repositionable component, such as a flexible polymer plug or repositionable adhesive patch, for plugging one of the weep holes. The repositionable component can be left in place or removed as desired by the user. In an alternative embodiment, both weep holes  272  could be plugged initially, and the user could remove the plug over the weep hole of their choice prior to use. 
     With reference to  FIG. 83  and in one embodiment, primary fluid channel  270  of main body  263  provides a fluid path  274  that communicates between the suction source (i.e., the barbed fitting  273 ) and distal end  207  of positioning rod  204 . Secondary fluid channel  271  branches off primary channel  270  and provides a fluid path  275  that communicates with the weep holes  272 . By placing secondary fluid channel  271  above primary fluid channel  270  and making the intersection of second fluid channel  271  with primary fluid channel  272  such that fluid path  275  is at an acute angle to fluid path  274 , the possibility of aspirated fluids passing down secondary channel  271  and out of weep holes  272  is eliminated or reduced. 
     While the weep holes  272  are positioned along the lateral edges of main body  263  of handle assembly  205 , it should be understood that they could be located on the top and/or bottom of main body  263  as well, and that while barbed fitting  273  is oriented along a central axis of main body  263 , it could be located along the length of main body  263  at an angle that is not parallel to the central axis of the main body. 
     It is possible for suction traveling through main body  263  to generate noise which can be transmitted into the ear canal even when the weep holes  272  are not blocked and suction is not being provided to distal end  207  of positioning rod  204 , and this noise can be disturbing to the patient. To prevent painful noise, a valve or shutoff can be located between the barbed fitting  273  and weep holes  272  such that negative pressure is still present, but the air flow that generates the noise is prevented. 
     Nose interface  217  is positioned at a distal end of handle assembly  205  and includes a stop component  296 . Stop component  296  includes a recessed area that is recessed into nose interface  217  and partially extends around a peripheral area of nose interface  217 . The recessed area includes a shelf portion  265  (illustrated in  FIGS. 2 and 3 ) located at one end of the recessed area and a plurality of spaced apart detents  269  ( FIG. 81 ) extending across the remaining of the recessed area. 
     To physically attach nose assembly  203  to handle assembly  205 , tab  262  on nose piece  260  of nose assembly  203  engages with shelf portion  265 . At the same time, a collar  276  ( FIGS. 78 and 79 ) on pull  256  mates with one or more protrusions  277 , such as a pair of protrusions, on rack  267  of handle assembly  205 .  FIG. 85  illustrates an enlarged perspective view of nose  213  and rack  267  before they mate together. More specifically, collar  276  includes a pair of opposing slots  278 . When nose piece  260  is pushed onto shelf portion  265  of nose interface  217 , collar  276  slides through protrusions  277  by way of slots  278  and is positioned on an internal side of protrusions  277 . Tab  262  is then rotated from shelf portion  265  to engage with a select detent of the plurality of detents  269 . Which of the detents is selected depends on the desired position or angle of nose assembly  203  relative to handle assembly  205 . When tab  262  is rotated, collar  276  also mates with protrusions  277  so that pull  256  cannot move out of position. In other words, once nose assembly  203  and handle assembly  205  are pushed together, rotating them with respect to one another results in tab  262  engaging with a select detent of the plurality of detents  269  and protrusions  277  on the rack  267  turning into a groove  279  on pull  256 . 
     Therefore, tab  262  provides a physical means of limiting the degree or rotation between nose assembly  203  and handle assembly  205 . In addition, tab  262  interfaces with the number of detents  269  on handle assembly  205 , which provide positive stops over the range of rotational adjustability between the nose and handle assemblies  203  and  205 . The user is able to manually twist nose assembly  203  in relation to handle assembly  205  to achieve the best orientation to achieve ventilation tube placement, while the positive stops provide sufficient resistance to movement so that nose  213  does not inadvertently rotate during tube insertion. In addition, by engaging tab  262  with stop component  296 , fluid path  274  through handle assembly  203  and positioning rod  204  is completed. While detents  269  are illustrated, other means of providing frictional resistance to rotation between nose assembly  203  and stop component  296  could be used. For example, merely providing a contact resistance between tab  262  and nose interface  217  of handle assembly  205  is sufficient. 
     Shelf portion  265  allows for ease of assembly of nose assembly  203  and handle assembly  205  including rotating tab  262  of nose  213  into the detents  269 . However, disassembling nose assembly  203  from handle assembly  205  requires increased force to rotate tab  262  of nose  213  back onto shelf portion  265 . Tab  262  being located on shelf portion  265  is the requisite position needed to assemble and disassemble nose assembly  203  to handle assembly  205 . This feature prevents the user from accidentally adjusting the rotational orientation of the two assemblies so far that the rack  267  and pull  256  are not connected, and therefore nose  213  cannot inadvertently fall off. 
       FIG. 82  illustrates a partial perspective view of handle assembly  205 ′ assembled to nose  213 ′ of insertion system  200 ′ and  FIG. 84  illustrates a section view of main body  263 ′ of handle assembly  205 ′ and nose  213 ′ of insertion system  200 ′. Handle assembly  205 ′ includes main body  263 ′ and nose  213 ′. As illustrated in  FIG. 84 , main body  263 ′ includes a primary fluid channel  270 ′ and a suction weep hole  272 ′. Weep hole  272 ′ is located on an upper surface of main body  263 ′. The proximal end of main body  263 ′ of handle assembly  205 ′ includes fitting  273 ′. Fitting  273 ′ can comprise soft flexible tubing so as to eliminate transferring any torque or twist created by a vacuum line to handle assembly  205 ′. 
     Suction, as provided by the suction source, passes through the primary fluid channel  270 ′ inside main body  263 ′ of handle assembly  205 ′. Primary fluid channel  270 ′ can be defined by polymer tubing, a t-fitting and a soft polymer double sealed component, which seals around nose  213 ′. This sealing component goes around nose  213 ′ and allows for replaceable noses while forming a seal and allows for rotation of the nose without breaking the seal. For example, the sealing component can be made of PVC, urethane, silicone or the like. Primary fluid channel  270 ′ is in fluid communication through aperture  264 ′ in drain-nose piece  260 ′ and down the positioning rod to the cutting edge of the cutting sheath and is also in communication with weep hole  272 ′. Weep hole  272 ′ provides the control for delivering suction to a distal end  207  of the positioning rod. In this embodiment, suction is available regardless of the position of scroll wheel  210 ′ ( FIGS. 4 and 5 ), the cutting sheath or pull  256 ′ ( FIG. 80 ). 
     Nose  213 ′ is positioned at a distal end of handle assembly  205 ′ and includes a stop component  296 ′. Stop component  296 ′ includes a recessed area that is recessed into a nose interface  217  and partially extends around a peripheral area of nose interface  217 ′. The recessed area includes a shelf portion  265 ′ located at one end of the recessed area and a plurality of spaced apart detents  269 ′ (of which only one is visible in  FIG. 82 ) extending across or about the recessed area. Like shelf portion  265 , shelf portion  265 ′ engages with tab  262 ′ when nose  213 ′ is initially attached to handle  212 ′. As illustrated, stop component  296 ′ includes three spaced apart detents. Each detent represents a locking point where tab  262 ′ can be engaged when nose  213 ′ is rotated for operation. 
     Although not specifically illustrated in  FIGS. 4 and 5 ,  FIG. 82  illustrates a plurality of visual markers located at a distal end of handle assembly  205 ′. In particular, handle assembly  205 ′ can include an insertion marker  294 ′ and stop markers  295 ′. Insertion marker  294 ′ corresponds with shelf portion  265 ′ and is in the shape of a triangle. In this way, a clinician can easily ascertain where a tab  262 ′ needs to align with and engage with stop component  296 ′ for the insertion or removal of handle  212 ′. Each stop marker  295 ′ corresponds with a detent  269 ′ and is in the shape of a dash. In this way, a clinician can easily ascertain the different rotational adjustments that tab  262 ′ can make to adjust the alignment of nose assembly  203 ′. 
     To physically attach nose assembly  203 ′ to handle assembly  205 ′, tab  262 ′ on drain-nose piece  260 ′ of nose assembly  203 ′ engages with stop component  296 ′. At the same time, a collar  276 ′ ( FIG. 80 ) on pull  256 ′ mates with component in handle assembly  205 ′ to provide a zero insertion force. Tab  262 ′ is then rotated from the shelf portion in a cam action to tighten nose  213 ′ and engage tab  262 ′ with a select detent of the plurality of detents  269 . Which of the detents is selected depends on the desired position or angle of nose assembly  203 ′ relative to handle assembly  205 ′. 
     Therefore, tab  262 ′ provides a physical means of limiting the degree or rotation between nose assembly  203 ′ and handle assembly  205 ′. In addition, tab  262 ′ interfaces with the number of detents  269 ′ on handle assembly  205 ′, which provide positive stops over the range of rotational adjustability between the nose and handle assemblies  203 ′ and  205 ′. Tab  262 ′ also includes a flange  297 ′ to push during rotational adjustment. Further, nose  213 ′ includes at least one circumferential rib or boss  299 ′ ( FIG. 82  illustrate a plurality of ribs or bosses  299 ′) to provide a grip feature for the push or pull or insertion or removal of nose  213 ′. 
     After assembly of nose assembly  203  or  203 ′ and handle assembly  205  or  205 ′, axial movement of rack  267  along a central axis  261  results in a corresponding movement of pull  256  or  256 ′, actuation member  214 , and therefore cutting sheath  206 . As previously described, rack  267  is coupled to actuating element or scroll wheel  210  or  210 ′ through the one or more drive gears  268 . Therefore, a user can rotate rotatable actuating element or scroll wheel  210  or  210 ′ in a direction  227  ( FIG. 81 ) from a first position (shown in  FIGS. 2, 3, 4 and 5 ), which is a forward position located toward stop component  296  or  296 ′, to a second position, which is a backward position located toward fitting  273  or  273 ′, to move cutting sheath  206 . More specifically, clockwise rotation or backwards rotation of scroll wheel  210  or  210 ′ retracts cutting sheath  206  and therefore deploys ventilation tube  215  since cutting sheath  206  is the element to which ventilation tube  215  is being constrained. While it is possible for scroll wheel  210  or  210 ′ to rotate forwards to deploy a ventilation tube, inadvertent movement imparted to the handle during such a rotation would result in a deeper penetration of the cutting sheath behind the patient and toward the user is a safety feature. 
     Scroll wheel  210  or  210 ′ can further comprise a physical feature or bump  231  or  231 ′ to provide physical feedback to the user. For example, bump  231  or ‘ 231 ’ located on the outer surface of scroll wheel  210  or  231 ′ can be a secondary material overmolded onto scroll wheel  210  or  210 ′ to provide better friction between the user and scroll wheel  210 . In particular, bump  231  or  231 ′ can have a width that is larger than a width of scroll wheel  210  or  210 ′ to allow a slight mechanical advantage to the user by providing a longer lever arm about the axis of rotation. Because many ventilation tube placement operations are performed through an operating microscope, it is common for surgeons to be handed instruments ‘blindly’, and they must be able to orient the device in their hand by feel instead of visually. Bump  231  or  231 ′ shown on scroll wheel  210  or  210 ′ in  FIGS. 2, 3, 4, 5 and 87  allows the clinician to feel where scroll wheel  210  or  210 ′ is before and during actuation. 
     The location of scroll wheel  210  or  210 ′ as illustrated in  FIGS. 2, 3, 4 and 5  allows insertion system  200  or  200 ′ to be actuated using a thumb or a forefinger, and in combination with the rotational adjustability of nose assembly  203  or  203 ′ and dual weep holes  272  or single weep hole  272 ′ allows insertion system  200  or  200 ′ to be used in a right-handed or left-handed orientation. When using the thumb to actuate scroll wheel  210 , an index finger is used to cover one of the weep holes  272 . When using the index finger to actuate scroll wheel  210 , the thumb is used to control suction by covering one of the weep holes  272 . The location of the single weep hole  272 ′ on insertion system  200 ′ eliminates the need for a means of plugging the unused weep hole. The same digit used to actuate scroll wheel  210 ′ is also used to cover weep hole  272 ′ to apply suction. The symmetrical location of weep hole  272 ′, combined with it&#39;s proximity to scroll wheel  210 ′ reduces the amount of hand movement required between the steps of actuation and suction application, and allows the user to employ the same digit to achieve both functions. 
     As also illustrated in  FIG. 81  and as previously discussed, the one or more drive gears  268 , which allow the rotational motion of scroll wheel  210  to be translated into linear motion for retracting cutting sheath element  206 , includes at least a scroll gear  268   a  and a reversing gear  268   b . The use of a sequence of gears as shown allows for a change in direction between scroll gear  268   a  and scroll wheel  210 . In addition, the use of a sequence of gears allows for a gearing up or down to achieve different mechanical advantages. For example, scroll wheel  210  may rotate through a greater or lesser angle than the final drive gear. 
       FIG. 86  illustrates a flexible polymer ventilation tube, such as T-tube  515   a  of  FIG. 37 , being radially loaded into cutting sheath  206 . Using a mandrel  1331  inserted into the inner lumen of ventilation tube  515   a , the ventilation tube  515   a  is positioned proximal to slot  224 , and then forced through the slot  224  and down into the inner lumen of cutting sheath  206 . While T-tube  515   a  is shown in  FIG. 29 , it should be realized that other types of tubes can be used including grommet type tubes. 
       FIG. 87  illustrates a flexible polymer ventilation tube, such as grommet tube  315   b  of  FIG. 7 , being axially loaded into cutting sheath  206 . Cutting sheath  206  is inserted into a snug loading tube  1341  (for example a clear or translucent polymer tube) such that the beveled distal end of cutting sheath  206  is inside loading tube  1341 . A flexible filament  1343 , such as a string or nylon monofilament, is passed through cutting sheath  206  such that a closed loop extends past the beveled distal end of cutting sheath  206  and out of the loading tube  1341  while the free ends extend out the proximal, unbeveled end of cutting sheath  206 . A flexible polymer ventilation tube, for example a silicone Paparella style such as tube  315   b , is passed through the loop in filament loop, and the loop is tightened down around the middle of the tube body. By holding onto the medial flange  384   b  of ventilation tube  315   b  while pulling on filament  1343 , the tube  315   b  is pulled into the polymer tube with the lateral flange  386   b  entering first. With ventilation tube  315   b  pulled completely into loading tube  1341 , the ventilation tube  315   b  can be rotated within cutting sheath  206  to align any tabs or flanges, such as tab  388   b , on ventilation tube  315   b  with the slot  224  in cutting sheath  206 . Ventilation tube  315   b  is then pulled into cutting sheath  206  with filament  1343 . When ventilation tube  315   b  is positioned correctly in cutting sheath  206 , one free end of filament  1343  is pulled while the other end is allowed to pull into cutting sheath  206  and around ventilation tube  315   b  so that it can be removed from around the ventilation tube and from inside cutting sheath  206 . The loading tube  1341  can then be removed from cutting sheath  206 , or it can be left in place to protect the cutting edge if the beveled distal end of cutting sheath  206  is sharpened. 
     In this loading method, a lancet style grind ensures that any cutting edges on the beveled portion of the sheath are located flush against the inner diameter of the loading tube, minimizing the chance that they will catch on or cut the ventilation tube during loading. A back grind on the cutting sheath would position the cutting edges on the inner diameter of the cutting sheath, which would be spaced away from the wall of a loading tube and could catch on or cut a flexible ventilation tube during the loading process. 
     As shown in  FIG. 87 , the loading tube  1341  may be circular along its entire length, or may match the outer geometry of the sheath. In another embodiment, loading tube  1341  may transition from an oval shape at a distal end to a circular shape where the distal end of the cutting sheath is positioned as shown in  FIG. 88 . An oval shape at the distal end of the loading tube where the ventilation tube is inserted helps ensure the medial and lateral flanges of the ventilation tube fold down in a repeatable fashion. Because medial and lateral flanges on a ventilation tube may be fully circumferential, and the cutting sheath has a slot, it is important to fold the medial and lateral flanges down such that they don&#39;t protrude through the slot, but that any tabs that are intended to protrude through the slot are positioned correctly such that they remain protruding. 
       FIG. 89  illustrates an alternative embodiment for a ventilation tube  3215  for axially loading into a cutting sheath. As described above, holes, or other features may be included on the ventilation tube&#39;s lateral flange or tabs that make it easier to load the ventilation tube. For example, a ventilation tube could have one or more holes  3217  in the lateral flange  3286  that a filament is passed through during loading that allows it to be pulled into the cutting sheath. Such a filament could then be removed before use, or could be left in place as a safety element which could be used to grasp the ventilation tube in cases where it may inadvertently fall into the inner ear during insertion. 
     The ability to remove a nose assembly from a handle assembly of an insertion system makes it easier to load ventilation tubes during manufacturing by enabling access to a proximal end of a positioning rod. In this way, it is possible to use a pulling filament to load ventilation tubes axially into the distal end of the cutting sheath. By using a removable attachment (such as a set screw) to anchor the actuating wire inside the nose assembly, the ventilation tube can be loaded before the cutting sheath is assembled onto the positioning rod. 
     The ventilation tube can also be loaded after the nose assembly and the handle assembly are fully assembled. The pulling filament can be fed through a loading tube and through the slot in the cutting sheath such that the ventilation tube can be pulled into the sheath without access to the proximal end of the cutting sheath for insertion of the pulling filament. 
     Loading methods that pull the ventilation tube into position by grasping it behind the lateral flange are preferred because they result in the proximal flange folding up and away from the main body of the ventilation tube and the distal flange folding down and away from the main body of the ventilation tube as well as potentially providing a slight stretch to the main body of the tube. This is desirable, because such a configuration increases the spacing between the lateral and medial flanges on the ventilation tube, which makes it easier to position the ventilation tube across the TM. Loading methods that push the ventilation tube axially into the distal end of the cutting sheath may result in the lateral flange of the ventilation tube folding down and toward the main body of the tube. 
       FIG. 90  illustrates a flow chart  3300  describing a manual process for inserting a ventilation tube  215  into a TM of the body using insertion system  200 . At block  3302 , ventilation tube  215  is loaded into cutting sheath  206 . At block  3304 , nose assembly  203  is assembled to handle assembly  205  by interlocking nose  213  with stop component  264 . It should be realized, however, that blocks  3302  and  3304  can be performed in the reverse order as well. Such loading procedures are illustrated and discussed in regards to  FIGS. 86-89 . At block  3306 , insertion end  202  is manually advanced through a body, for example the outer ear, such that distal end  209  of cutting sheath  206  pierces through a membrane, such as a TM. As discussed above, how far to insert insertion end  202  or distal end  209  of cutting sheath  206  into the TM is determined by a visual or physical indicators located at insertion end  202 . In one embodiment, a visual indicator can be a tab  288  located on ventilation tube  215  that is protruding through a slot  224  in cutting sheath  206 . Other or additional visual or physical indicators can be located on the outer surface of cutting sheath  206  including sensing elements as described in detail above. After insertion end  202  is inserted through the TM, cutting sheath  206  retraction is accomplished by rotating rotatable actuating element  210  on the handle assembly  205  from a first position to a second position (i.e., in a direction toward the user of the insertion system  200 ) as described in block  3308 . This movement causes cutting sheath  206  to fully retract from the TM. Removal of insertion end is then performed at block  3310  by removing insertion end  202  and therefore insertion system  200  out of the body or outer ear. 
       FIG. 91  illustrates a flow chart  3400  describing a semi-automated process for inserting a ventilation tube into a TM of the body using an insertion system. At block  3402 , an insertion end is manually advanced through an outer ear such that a distal end of a cutting sheath pierces through the TM as described at block  3404  and the ventilation tube is located across the TM as described in block  3406 . As discussed above, how far to insert insertion end  202  or distal end of cutting sheath into the TM is determined by a visual or physical indicator. After the insertion end is inserted through the TM, a deployment mechanism is actuated at block  3408 . Actuation of the deployment mechanism provides for the automatic retraction of the cutting sheath as described in block  3410  and therefore the automated deployment of a ventilation tube as described at block  3412 . The automated retraction causes cutting sheath  206  to fully retract from the TM as described in block  3414 . At block  3416 , suction can be optionally applied and at block  3418  the insertion system is manually removed from the ear canal. 
       FIG. 92  illustrates an embodiment of an insertion system  3500  comprising elements which facilitate the semi-automated placement of ventilation tubes as described above in  FIG. 91 . Shown is a spring  3555 , which automatically retracts the cutting sheath when a deployment mechanism is depressed. In  FIG. 33 , spring  3555  is configured to pull back on rotatable element or scroll wheel  3510 . Also shown are an optional damper  3557  to slow the cutting sheath retraction to a controlled rate, and a shock absorber  3559 , which stops the range of motion of the retraction. Both damper  3557  and shock absorber  3559  by themselves or working in combination can decrease the noise generated by insertion system  3500  during deployment, reducing the noxious stimuli which may cause a patient to move upon ventilation tube deployment. Damper  3557  also allows for the use of an oversized spring  3555  to provide more than sufficient actuation force without a comparable increase in the speed of the cutting sheath retraction or the noise generated by the retraction mechanism during motion or at the end of its range of motion. 
       FIG. 93  illustrates yet another embodiment of an insertion system  3600  comprising a removable element  3649  that can be slid onto the cutting sheath (hidden from view in  FIG. 93 ) such that the cutting sheath is covered and protected. The removable covering element  3649  can also include a means for the application of a topical anesthetic or other medication to the ear canal or TM. Shown is a loop  3651  that could be used to apply an anesthetic, such as phenol, to the TM. After application of the anesthetic, the covering element  3649  can be removed such that the cutting sheath is exposed and can be used to implant a ventilation tube. The removable element  3649  could also be shaped so as to function similarly to a curette and could be used to clean the ear canal prior to tube placement. The removable element  3649  could be shaped so as to accept and hold an absorbable element such as a piece of open cell foam or absorbent cloth, which could then be used to transport a medication down the ear canal. 
     The removable nature of the nose assembly from the ‘rack and pull’ interface between the nose assembly and the handle assembly allow for function-specific nose assemblies other than the insertion type function of the describe nose assembly  203  for inserting a ventilation tube. For example, a nose assembly that only applies topical analgesic is possible. In such an embodiment, the cutting sheath could be replaced by an absorbent pad, and the actuation mechanism could trigger the release of an analgesic stored within the hollow positioning rod or another element such that it is absorbed into the nose assembly for application. A nose assembly specialized for the creation of myringotomies only without subsequent tube placement is another exemplary function-specific assembly. Such a nose assembly could comprise an element to incise the TM and an element to capture a sample of fluid for laboratory analysis. Upon the incision and capture of a sample, the entire nose assembly could be removed from the handle and sent to a laboratory. A nose assembly for spraying or atomizing medication is another exemplary function-specific assembly. Such a nose assembly could comprise a distribution element for dispersing the medicine located along or in place of the positioning rod. Actuation at the handle would result in the release and distribution of the medication. A viewing nose assembly is still another exemplary function-specific assembly. The viewing nose assembly could comprise a positioning member with a flexible distal portion and a viewing member, such as a fiber optic scope. Actuation of the scroll wheel would move the flexible distal portion of the viewing member, allowing a clinician to change the viewing zone inside the body. 
     A nose assembly for inserting ear wicks of various length is yet another exemplary function-specific assembly and could comprise all of the components described for nose assembly  203 , but also comprises an adjustable visualization element that lets the user adjust a visualization tab independent of the sheath. Because an ear wick may not include a visualization tab, a tab on the cutting sheath, or on a secondary sheath may be necessary. For example,  FIG. 68  illustrates a visualization tab  688  on safety sheath  637 . A visualization tab on a secondary sheath that is frictionally attached over a cutting sheath would allow the user to manually adjust the depth of the visualization tab, and would also allow the user to rotate the visualization tab around the cutting sheath to for optimal placement and direct visualization. Such an adjustable secondary visualization tab could be used on any nose assembly where adjustability or enhanced depth visualization is desired. Other function-specific removable assemblies than those that are described are possible. 
       FIG. 94  illustrates a section view of insertion end  202  of insertion system  200  interfacing with a speculum-like device  3793 .  FIG. 84  illustrates an enlarged view of  FIG. 94 . In this embodiment, safety sheath  637  serves to cover the joint between the cutting sheath  206  and the positioning rod  204 , ensuring that the proximal end of the safety sheath does not contact the front lip of the speculum  3793  during use, which could interfere with the retraction of cutting sheath  206  required for ventilation tube deployment. An alternative embodiment uses a cutting sheath with a tapered proximal end to minimize the potential for interference with a speculum instead of a safety sheath. In the embodiment illustrated in  FIGS. 94 and 95 , safety sheath  637  may also protect the distal end cutting edge  209  prior to and/or after device use, but it may also just cover the joint between cutting sheath  206  and positioning rod  204 , and not need to be repositioned before and/or after ventilation tube deployment. 
       FIGS. 96-98  illustrate an embodiment of a speculum-like device  3893  with unique features for interfacing with an insertion system  200 .  FIG. 96  is a perspective view,  FIG. 97  is a end view and  FIG. 98  is a side view.  FIGS. 96-98  illustrate speculum  3893  with a clear cover  3895  over the larger opening. This clear cover  3895  has an opening  3896  that is smaller than the normal speculum opening  3897  through which the insertion end  202  of insertion system  200  is passed. This smaller opening  3896  provides for a surface to rest the positioning rod  204  against to improve stability during ventilation tube insertion. Alternatively or in addition to, a brace or rest  3898  may be included on the inner surface of the speculum  3893   b , on the positioning rod (not illustrated), or on both. 
     Speculum  3893  may also include a passage and/or a clip for passage or attachment of one or more fiber-optic scopes or similar visualization tools. While the insertion system can be used under direct visualization or under magnification, such as that provided by an operating otoscope or microscope, the use of fiber optic scopes could also be used. The ability to attach the fiber optic scope to a speculum like device allows the clinician to hold and position both devices with a single hand. These passages and attachments could also be used for passing or attaching tubes for the administration of drugs such as analgesics or antibiotics, or the passages themselves may act as a passage for drugs. 
     Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claim.