Abstract:
A method for use with a balloon catheter device that includes a selectively bendable portion with a balloon disposed thereon, a control device for controlling bending of the selectively bendable portion, and a camera located at an end of a distal portion, includes inserting the distal portion into the nostril while the distal portion is straight; viewing an image provided by the camera; stopping insertion of the distal portion after the ethmoidal bulla is viewed in the image; articulating the distal portion in an upward direction to view the opening to the frontal sinus ostium or a downward direction to view the opening to the maxillary sinus ostium using the control device; inserting the distal portion into the frontal sinus ostium or the maxillary sinus ostium while the distal portion remains in the bent position; and inflating the balloon in the frontal sinus ostium or the maxillary sinus ostium.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to an otorhinolaryngological treatment method to be used for treatment of sinusitis and the like. 
         [0003]    2. Description of Related Art 
         [0004]    A paranasal sinus is an intraosseous cavity adjacent to a nasal cavity, and communicates with the nasal cavity through a small hole called the natural ostium. Secretions, bacteria, and the like in the paranasal sinus are excreted into the nasal cavity through the natural ostium. When the mucous membrane in the nasal cavity or paranasal sinus is swollen due to common cold-induced rhinitis or allergic rhinitis or the like, or the inside of the nasal cavity is narrowed due to deflected nasal septum or hypertrophic rhinitis or the like, the natural ostium may become stenosed and chronic inflammation may be generated in the paranasal sinus. Such a disease is called sinusitis. Conventionally, the method for treatment of sinusitis has generally been a surgical operation in which the lesion causing stenosis of the natural ostium is removed by use of forceps and a drill or the like while confirming the video image of the inside of the nasal cavity through an endoscope. In recent years, however, a sinusitis treatment method based on the use of a balloon catheter and not including a surgical operation has been developed, and this method has been drawing attention from the viewpoint of minimal invasiveness to the patient. 
         [0005]    In the treatment method developed recently, a guide wire and a balloon catheter are sequentially inserted into the nasal cavity, and, after it is confirmed that the balloon catheter has been disposed in the natural ostium (for example, using a radioscopic method), the balloon catheter is expanded to force open the stenosed part of the natural ostium. According to this treatment method, the communicating passage between the nasal cavity and the paranasal sinus can be recovered without significant bleeding in the nasal cavity or damage to the mucous membrane. In connection with this technique, WO2006/034008 proposes a balloon catheter in which a plurality of radiopaque markers for marking the balloon proximal end, distal end and the like are disposed on the inner surface of the balloon. On the other hand, from the viewpoint of prevention of exposure of the patient to X-rays, there is an increasing demand for a balloon catheter and method of using such which enables easy positioning of the balloon inside the nasal cavity without relying on radioscopy. All documents cited in this disclosure are incorporated herein by reference in their entireties. 
       SUMMARY 
       [0006]    It is an object of the present invention to provide otorhinolaryngological treatment methods in which positioning of an expansion body inside a nasal cavity can be easily carried out without need for radioscopy. 
         [0007]    One embodiment of the present invention provides a method for use with a balloon catheter device that includes a selectively bendable portion with a balloon disposed thereon, a control device for controlling bending of the selectively bendable portion, and a camera located at an end of a distal portion, the method comprising inserting the distal portion into the nostril while the distal portion is straight; viewing an image provided by the camera; stopping insertion of the distal portion after the ethmoidal bulla is viewed in the image; articulating the distal portion in an upward direction to view the opening to the frontal sinus ostium or a downward direction to view the opening to the maxillary sinus ostium using the control device; inserting the distal portion into the frontal sinus ostium or the maxillary sinus ostium while the distal portion remains in the bent position; and inflating the balloon in the frontal sinus ostium or the maxillary sinus ostium. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a schematic view of a treatment system as used in some embodiments of the present invention. 
           [0009]      FIGS. 2A-B  show a longitudinal sectional view of a balloon catheter device that can be used in embodiments of the present invention,  FIG. 2A  showing the device in a non-expanded state, and  FIG. 2B  showing the device in an expanded state. 
           [0010]      FIGS. 3A-B  show a longitudinal sectional view of a balloon catheter device that can be used in embodiments of the present invention,  FIG. 3A  showing the device in a non-articulated state, and  FIG. 3B  showing the device in an articulated state. 
           [0011]      FIGS. 4A-B  show a longitudinal sectional view of a balloon catheter device that can be used in embodiments of the present invention,  FIG. 4A  showing the device with a camera and LED light in a non-extended state, and  FIG. 4B  showing the device with a camera and LED light in an extended state. 
           [0012]      FIGS. 5A-N  show a method of treating the sphenoidal sinus according to some embodiments of the invention.  FIG. 5A  shows the nasal cavity and significant structures therein.  FIG. 5B  shows the nasal cavity with a balloon catheter positioned in the sphenoidal sinus ostium.  FIG. 5C  shows the positioning of the balloon catheter for downward articulation.  FIG. 5D  shows approach of the distal end of the balloon catheter to the nasal cavity.  FIG. 5E  shows insertion of the distal end of the balloon catheter into the nasal cavity.  FIG. 5F  shows advancing the distal end of the balloon catheter to the side of the middle turbinate.  FIG. 5G  shows an image roughly corresponding to  FIG. 5F  as seen through a CCD camera.  FIG. 5H  shows approach of the distal end of the balloon catheter to one of the openings to the ostium of the sphenoidal sinus.  FIG. 5I  shows an image roughly corresponding to  FIG. 5H  as seen through a CCD camera.  FIG. 5J  shows insertion of the distal end of the balloon catheter into the ostium of the sphenoidal sinus.  FIG. 5K  shows an image roughly corresponding to  FIG. 5J  as seen through a CCD camera.  FIG. 5L  shows an image roughly corresponding to  FIG. 5J  as seen through a CCD camera.  FIG. 5M  shows expansion of the balloon catheter.  FIG. 5N  shows removal of the distal end of the balloon catheter from the ostium of the sphenoidal sinus and viewing of the sphenoidal sinus ostium. 
           [0013]      FIGS. 6A-R  show a method of treating the frontal sinus according to some embodiments of the invention.  FIG. 6A  shows the nasal cavity and significant structures therein.  FIG. 6B  shows the nasal cavity with a balloon catheter positioned in the frontal sinus ostium.  FIG. 6C  shows the positioning of the balloon catheter for upward articulation.  FIG. 6D  shows approach of the distal end of the balloon catheter to the nasal cavity.  FIG. 6E  shows insertion of the distal end of the balloon catheter into the nasal cavity.  FIG. 6F  shows advancing the distal end of the balloon catheter to the side of the middle turbinate.  FIG. 6G  shows an image roughly corresponding to  FIG. 6F  as seen through a CCD camera.  FIG. 6H  shows approach of the distal end of the balloon catheter to the ethmoidal bulla.  FIG. 6I  shows an image roughly corresponding to  FIG. 6H  as seen through a CCD camera.  FIG. 6J  shows advancing the distal end of the balloon catheter along the groove (hiatus semilunaris) between the ethmoidal bulla and the uncinate process.  FIG. 6K  shows an image roughly corresponding to  FIG. 6J  as seen through a CCD camera.  FIG. 6L  shows approach of the distal end of the balloon catheter to one of the openings to the ostium of the frontal sinus.  FIG. 6M  shows an image roughly corresponding to  FIG. 6L  as seen through a CCD camera.  FIG. 6N  shows insertion of the distal end of the balloon catheter into the ostium of the frontal sinus.  FIG. 6O  shows an image roughly corresponding to  FIG. 6N  as seen through a CCD camera.  FIG. 6P  shows an image roughly corresponding to  FIG. 6N  as seen through a CCD camera.  FIG. 6Q  shows expansion of the balloon catheter.  FIG. 6R  shows removal of the distal end of the balloon catheter from the ostium of the frontal sinus and viewing of the frontal sinus ostium. 
           [0014]      FIGS. 7A-R  show a method of treating the maxillary sinus according to some embodiments of the invention.  FIG. 7A  shows the nasal cavity and significant structures therein.  FIG. 7B  shows the nasal cavity with a balloon catheter positioned in the maxillary sinus ostium.  FIG. 7C  shows the positioning of the balloon catheter for downward articulation.  FIG. 7D  shows approach of the distal end of the balloon catheter to the nasal cavity.  FIG. 7E  shows insertion of the distal end of the balloon catheter into the nasal cavity.  FIG. 7F  shows advancing the distal end of the balloon catheter to the side of the middle turbinate.  FIG. 7G  shows an image roughly corresponding to  FIG. 7F  as seen through a CCD camera.  FIG. 7H  shows approach of the distal end of the balloon catheter to the ethmoidal bulla.  FIG. 7I  shows an image roughly corresponding to  FIG. 7H  as seen through a CCD camera.  FIG. 7J  shows advancing the distal end of the balloon catheter along the groove between the ethmoidal bulla and the uncinate process.  FIG. 7K  shows an image roughly corresponding to  FIG. 7J  as seen through a CCD camera.  FIG. 7L  shows approach of the distal end of the balloon catheter to one of the openings to the ostium of the maxillary sinus.  FIG. 7M  shows an image roughly corresponding to  FIG. 7L  as seen through a CCD camera.  FIG. 7N  shows insertion of the distal end of the balloon catheter into the ostium of the maxillary sinus.  FIG. 7O  shows an image roughly corresponding to  FIG. 7N  as seen through a CCD camera.  FIG. 7P  shows an image roughly corresponding to  FIG. 7N  as seen through a CCD camera.  FIG. 7Q  shows expansion of the balloon catheter.  FIG. 7R  shows removal of the distal end of the balloon catheter from the ostium of the maxillary sinus and viewing of the maxillary sinus ostium. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0015]    Embodiments of the present invention are described below referring to the drawings. For convenience of description, the dimensional ratios among components in each of the drawings as well as the dimensional ratios of the same components among the plurality of drawings are modified as required, so that they are not necessarily coincident with the actual ratios. 
       I. Structure of Treatment Device According to the Present Invention 
       [0016]      FIG. 1  is a schematic illustration of the general structure of a treatment system including a catheter  1  as a treatment device according to a first embodiment of the present invention. As shown in  FIG. 1 , the catheter  1  includes a first elongated body  11  constituting a main body thereof, a balloon  12  as an expansion body for forcing open a stenosed part of a natural ostium, a CCD camera  13  as imaging unit for obtaining an image of the inside of a nasal cavity, an LED light  14  as a lighting unit for illuminating the inside of the nasal cavity, and a hub  15  having the function of a proximal operating section to be operated by the operator as well as the function as a connection port for connection to an external apparatus. Hub  15  has an articulation control  17  and a camera advancement control  16 . 
         [0017]    Here, the term “CCD camera” means a digital video camera using a CCD image sensor as an imaging element. The hub  15  includes an image port  15   a  as the connection port for connection to the external apparatus, a pressure supply port  15   b , and a light supply port  15   c . The ports  15   a - 15   c  are described in more detail below. The catheter  1  may be inserted into the patient&#39;s nasal cavity from its end portion where the CCD camera  13  is disposed, to be used for treatment of sinusitis. In the following description, the end portion of the catheter  1  for insertion into the nasal cavity will be referred to as distal end, and the end portion on the opposite side will be referred to as proximal end. 
         [0018]    As shown in  FIG. 1 , the balloon catheter  1  is connected to a display device  32  such as an LCD through the image port  15   a  of the hub  15 , to a pressure supply device  30  such as an indeflator through the pressure supply port  15   b , and to a light power source device  31  through the light supply port. Here, the display device  32  displays thereon an image obtained by the CCD camera  13 . The pressure supply device  30  supplies the balloon  12  with a liquid or the like. The light power source device  31  supplies the LED light  14  with electric power. 
         [0019]    The imaging unit in the present embodiment is not restricted to the CCD camera, but may be any of a digital video camera using other imaging element such as a CMOS image sensor, an image fiber for obtaining and transmitting images by means of optical fibers, and an imaging system for transmitting images by means of an objective lens and an optical system including a plurality of relay lenses. The “image obtaining plane” in the cases of using various cameras or optical imaging systems means a predetermined part of the imaging unit disposed so as confront an organ in a living body at the time of introduction into the inside of the living body, and the image obtaining plane may be a distal-end surface of a protective member of the image sensing element or a lens, for example. 
         [0020]    The lighting unit in the present embodiment is not limited to the LED light, but may be other lighting units such as a halogen lamp and a high-intensity discharge lamp (HID lamp). Apart from the example shown in  FIG. 1  where the LED lamp  14  is attached to the distal end of the catheter  1 , the catheter  1  can also be configured such that light generated by the light power source device  31  is guided to its distal end through a light guide made by glass or plastic. 
         [0021]      FIGS. 2A and 2B  are enlarged illustrations of a longitudinal sectional view showing the vicinity of the distal end of the balloon catheter  1  of  FIG. 1 . As shown in  FIGS. 2A and 2B , the first elongated body  11  has multiple internal lumen. As shown in  FIG. 2A , the balloon  12  has a non-expanded state. As shown in  FIG. 2B , the balloon  12  has an expanded state. 
         [0022]    The change between the non-expanded state and expanded states for balloon  12  as shown in  FIGS. 2A and 2B  respectively may be effectuated through use of pressure supply device  30  and a lumen of first elongated body  11  in communication with balloon  12  and pressure supply device  30 . 
         [0023]      FIGS. 3A and 3B  are enlarged illustrations of a longitudinal sectional view showing the vicinity of the distal end of the catheter  1  of  FIG. 1 . As shown in  FIG. 3A , the catheter  1  has a non-articulated state. As shown in  FIG. 3B , the catheter  11  has an articulated state. The change between the non-articulated state and articulated states for catheter  1  as shown in  FIGS. 3A and 3B  respectively is effectuated through use of articulation control  17 . Catheter  1  as discussed herein only articulates on a single plane and in a single direction from the non-articulated position shown in  FIG. 3A . Changes to this limitation may create slight changes to the methods described herein for other embodiments of the invention. While catheter  1  of  FIGS. 3A and 3B  may be the same catheter  1  of  FIGS. 2A and 2B , the detail of the lumens in the catheter  1  shown in  FIGS. 2A and 2B  is omitted in  FIGS. 3A and 3B  for simplicity. The articulation of the catheter device may be performed manually using mechanical articulation devices that are known in the art. The articulation by be performed using electrical devices using, for example, piezoelectric elements or artificial muscle elements. The use of piezoelectric elements is discussed, for example, in U.S. Patent Publication No. 2005/0085693. The articulation may alternatively be performed, for example, using elements made of shape memory alloys that are articulated thermally or electrically. Examples of such devices are described in U.S. Pat. No. 5,624,380 and U.S. Patent Publication No. 2008/0097159. 
         [0024]      FIGS. 4A and 4B  are enlarged illustrations of a longitudinal sectional view showing the vicinity of the distal end of the catheter  1  of  FIG. 1 . As shown in  FIG. 4A , CCD camera  13  and LED light  14  may have a non-extended state. As shown in  FIG. 4B , CCD camera  13  and LED light  14  may have an extended state. The change between the non-extended state and extended states for CCD camera  13  and LED light  14  as shown in  FIGS. 4A and 4B  respectively is effectuated through use of camera advancement control  16 . While catheter  1  of  FIGS. 4A and 4B  is the same catheter  1  of  FIGS. 2A and 2B , the detail of the lumens in the catheter  1  shown in  FIGS. 2A and 2B  is omitted in  FIGS. 4A and 4B  for simplicity. 
       II. Method for Treatment of Sinusitis of the Sphenoidal Sinus 
       [0025]    Now, a method of treating sinusitis in the sphenoidal sinus using catheter  1  from  FIGS. 1 ,  2 A-B,  3 A-B, and  4 A-B will be described below referring to  FIGS. 5A-N . 
         [0026]      FIG. 5A  is an illustration of the nasal cavity and structures therein contained as are pertinent to the present method. 
         [0027]      FIG. 5A  shows the openings  501  of the sphenoidal sinus that define the ostium connecting sphenoidal sinus  502  to the rest of the nasal cavity. The nasal cavity can be accessed by passing through nasal vestibule  509 . Inside the nasal cavity are the inferior nasal turbinate  511 , middle nasal turbinate  513 , and superior nasal turbinate  515 . Defining the spaces between these turbinates are inferior nasal meatus  510 , middle nasal meatus  512 , and superior nasal meatus  514 .  FIG. 5B  shows the same structures of  FIG. 5A  with catheter  1  having elongated body  11  and balloon  12  properly positioned for treating sinusitis of sphenoidal sinus  502 . The following discussion explains how the positioning shown in  FIG. 5B  is achieved. 
         [0028]    As shown in  FIG. 5C , catheter  1  is first positioned so it will articulate in a downwards direction from its non-articulated position. With catheter  1  properly positioned for downward articulation, the catheter distal end is positioned to enter the nasal cavity through nasal vestibule  509  as shown in  FIG. 5D . As shown in  FIG. 5E , the catheter  1  is advanced into the nasal cavity through nasal vestibule  509  so that balloon  12 , CCD camera  13 , and LED light  14  fully enter the nasal cavity. 
         [0029]      FIG. 5F  is an illustration of a view of the inside of the nasal cavity as seen using CCD camera  13 . As shown, the operator of the catheter  1  identifies middle nasal turbinate  513  and nasal septum  516 . Inferior nasal turbinate  511  and middle nasal meatus  512  are shown and labeled for clarity. Having identified middle nasal turbinate  513  and nasal septum  516 , the operator advances the distal end of catheter  1  between those two structures through the common nasal meatus  531  in an area roughly identified as area  530 .  FIG. 5G  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 5F . 
         [0030]    Having advanced catheter  1  through area  530 , the operator uses CCD camera  13  to advance the distal end of catheter  1  until the opening  501  of the sphenoidal sinus  502  is visible as shown in  FIG. 5H .  FIG. 5I  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 5H . Where other openings, other than the desired opening  501  exist in the same general area as opening  501 , the operator may need to observe the openings using the CCD camera  13  as shown in  FIG. 511  and  FIG. 5I  in order to identify the correct ostium for insertion. Continuing to advance the distal end of catheter  1  toward the opening  501  of sphenoidal sinus  502 , the operator advances the balloon  12  into the sphenoidal sinus ostium, which connects the sphenoidal sinus  502  to the rest of the nasal cavity as shown in  FIG. 5J . As depicted, the operator may need to articulate the distal end of catheter  1  as the distal end is advanced through the ostium so that the catheter  1  will continue advancing along the path of that ostium.  FIG. 5K  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 5J . In particular,  FIG. 5K  shows the inside of the sphenoidal sinus ostium and the opening  501  of the sphenoidal sinus  502  that exits the sphenoidal sinus ostium and enters the sphenoidal sinus  502 . As such, the image shows how the operator may view the opening  501  of the sphenoidal sinus  502  as he advances the distal end of catheter  1  through the sphenoidal sinus ostium.  FIG. 5L  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 5J , wherein the distal end of catheter  1  has been advanced through the sphenoidal sinus ostium and now is sufficiently advanced into the sphenoidal sinus  502  so as to allow the operator to view the interior wall of the sphenoidal sinus  502  In some situations, it may be advantageous to advance the distal end of catheter  1  until it just enters the sphenoidal sinus  502 , and then use the camera advancement control  16  to advance just the CCD camera  13  and LED light  14  further into the sphenoidal sinus  502  in order to see the interior wall of the sphenoidal sinus  502  as shown in  FIG. 5L . 
         [0031]    Once balloon  12  is positioned in the sphenoidal sinus ostium, the operator changes balloon  12  to its expanded state as shown in  FIG. 5M . This expansion is effective to correct the stenosis of the ostium. Once treatment by means of expansion is complete, the operator returns balloon  12  to its non-expanded state and removes it from the ostium. This removal may require articulation of the distal end of catheter  12  substantially in reverse of the articulation that the operator effectuated to allow the balloon  12  to enter the ostium. 
         [0032]    Once the balloon  12  is fully removed from the ostium, the operator can use CCD camera  13  to inspect the ostium in order to verify that the treatment was successful to correct the stenosis of the ostium as shown in  FIG. 5N . The operator then removes catheter  1  from the nasal cavity. 
       III. Method for Treatment of Sinusitis of the Frontal Sinus 
       [0033]    A method of treating sinusitis in the frontal sinus using balloon catheter  1  will be described below referring to  FIGS. 6A-R . 
         [0034]      FIG. 6A  is an illustration of the nasal cavity and structures therein contained as are pertinent to the present method. 
         [0035]      FIG. 6A  shows the openings  601  of the frontal sinus  602  that define the ostium connecting frontal sinus  602  to the rest of the nasal cavity. The lower opening  601  of the frontal sinus  602  is shown in broken line to indicate that it is obscured behind tissue of the nasal cavity and as such is not directly visible in the present view of the nasal cavity.  FIG. 6A  shows the structures present in  FIG. 5A , including: nasal vestibule  509 , inferior nasal turbinate  511 , middle nasal turbinate  513 , superior nasal turbinate  515 , inferior nasal meatus  510 , middle nasal meatus  512 , and superior nasal meatus  514 . Middle nasal turbinate  513  is filled with a slanted line pattern to indicate that part of the structure has been cut away in this illustration to allow the viewing of other structures that would otherwise be obscured.  FIG. 6A  additionally shows ethmoidal bulla  610 , uncinate process  611 , and a groove  612  between the ethmoidal bulla  610  and uncinate process  611 . 
         [0036]      FIG. 6B  shows the same structures of  FIG. 6A  with catheter  1  having elongated body  11  and balloon  12  properly positioned for treating sinusitis of frontal sinus  602 . The following discussion explains how the positioning shown in  FIG. 6B  is achieved. 
         [0037]    As shown in  FIG. 6C , catheter  1  is first positioned so it will articulate in an upwards direction from its non-articulated position. With catheter  1  properly positioned for upward articulation, the catheter distal end is positioned to enter the nasal cavity through nasal vestibule  509  as shown in  FIG. 6D . As shown in  FIG. 6E , the catheter  1  is advanced into the nasal cavity through nasal vestibule  509  so that balloon  12 , CCD camera  13 , and LED light  14  fully enter the nasal cavity. 
         [0038]      FIG. 6F  is an illustration of a view of the inside of the nasal cavity as seen using CCD camera  13 . As shown, the operator of the catheter  1  identifies middle nasal turbinate  513  and nasal septum  516 . Inferior nasal turbinate  511  and middle nasal meatus  512  are shown and labeled for clarity. Having identified middle nasal turbinate  513  and nasal septum  516 , the operator advances the distal end of catheter  1  in the space at the side of middle nasal meatus  512  that is opposite of nasal septum  516  as identified as area  630 .  FIG. 6G  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 6F . 
         [0039]    Having advanced catheter  1  through area  630 , the operator uses CCD camera  13  to advance the distal end of catheter  1  until the ethmoidal bulla  610  is in view as shown in  FIG. 6H . The operator advances the distal end of catheter  1  past the uncinate process  611  and approaches the ethmoidal bulla  610  until nearly touching it. This movement entails moving towards the area  631 .  FIG. 6I  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 6H . 
         [0040]    Once the operator has advanced the distal end of catheter  1  sufficiently close to the ethmoidal bulla  610 , the operator articulates the distal end of the catheter  1  in an upward direction and is then able to view the groove  612  between ethmoidal bulla  610  and uncinate process  611  as shown in  FIG. 6J . The operator advances the distal end of catheter  1  in this upward articulated state along groove  612  as also shown in  FIG. 6J .  FIG. 6K  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 6J . 
         [0041]    The operator advances the distal end of catheter  1  along groove  612  until the opening  601  of the frontal sinus  602  is visible as shown in  FIG. 6L .  FIG. 6M  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 6L . Where other openings, other than the desired opening  601  exist in the same general area as opening  601 , the operator may need to observe the openings using the CCD camera  13  as shown in  FIG. 6L  and  FIG. 6M  in order to identify the correct ostium for insertion. Continuing to advance the distal end of catheter  1  toward the opening  601  of frontal sinus  602 , the operator advances the balloon  12  into the ostium connecting frontal sinus  602  to the rest of the nasal cavity as shown in  FIG. 6N . As depicted, the operator may need to articulate the distal end of catheter  1  as that distal end is advanced through the ostium so that the catheter  1  will continue advancing along the path of that ostium.  FIG. 6O  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 6N . In particular,  FIG. 6O  shows the inside of the frontal sinus ostium and the opening  601  of the frontal sinus  602  that exits the frontal sinus ostium and enters the frontal sinus  602 . As such, the image shows how the operator may view the opening  601  of the frontal sinus  602  as he advances the distal end of catheter  1  through the frontal sinus ostium.  FIG. 6P  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 6N , wherein the distal end of catheter  1  has been advanced through the frontal sinus ostium and now is sufficiently advanced into the frontal sinus  602  so as to allow the operator to view the interior wall of the frontal sinus  602 . In some situations, it may be advantageous to advance the distal end of catheter  1  until it just enters the frontal sinus  602 , and then use the camera advancement control  16  to advance just the CCD camera  13  and LED light  14  further into the frontal sinus  602  in order to see the interior wall of the frontal sinus  602  as shown in  FIG. 6P . In some situations, it may be necessary to expand the balloon  12  to correct stenosis of the passages leading to the openings  601  of the frontal sinus  602 . 
         [0042]    Once balloon  12  is positioned between openings  601  of the frontal sinus  602 , the operator changes balloon  12  to its expanded state as shown in  FIG. 6Q . This expansion is effective to correct the stenosis of the ostium. Once treatment by means of expansion is complete, the operator returns balloon  12  to its non-expanded state and removes it from the ostium. This removal may require articulation of the distal end of catheter  12  substantially in reverse of the articulation that the operator effectuated to allow the balloon  12  to enter the ostium. 
         [0043]    Once the balloon  12  is fully removed from the ostium, the operator can use CCD camera  13  to inspect the ostium in order to verify that the treatment was successful to correct the stenosis of the ostium as shown in  FIG. 6R . The operator then removes catheter  1  from the nasal cavity. 
       IV. Method for Treatment of Sinusitis of the Maxillary Sinus 
       [0044]    Now, a method of treating sinusitis in the maxillary sinus using catheter  1  from  FIGS. 1 ,  2 A-B,  3 A-B, and  4 A-B will be described below referring to  FIGS. 7A-R . 
         [0045]      FIG. 7A  is an illustration of the nasal cavity and structures therein contained as are pertinent to the present method. 
         [0046]      FIG. 7A  shows the openings  701  of the maxillary sinus  702  that define the ostium connecting maxillary sinus  702  to the rest of the nasal cavity. The lower opening  701  of the maxillary sinus  702  is shown in broken line to indicate that it is obscured behind tissue of the nasal cavity and as such is not directly visible in the present view of the nasal cavity. The maxillary sinus  702  is likewise shown in broken line as it would be obscured by tissue as being in the background of the present view of the nasal cavity.  FIG. 7A  shows the structures present in  FIG. 6A , including: nasal vestibule  509 , inferior nasal turbinate  511 , middle nasal turbinate  513 , superior nasal turbinate  515 , inferior nasal meatus  510 , middle nasal meatus  512 , superior nasal meatus  514 , ethmoidal bulla  610 , uncinate process  611 , and a groove  612  between the ethmoidal bulla  610  and uncinate process  611 . Superior nasal turbinate  515 , middle nasal turbinate  513 , and inferior nasal turbinate  511  are filled with a slanted line pattern to indicate that part of each of these structures has been cut away in this illustration to allow the viewing of other structures that would otherwise be obscured. 
         [0047]      FIG. 7B  shows the same structures of  FIG. 7A  with catheter  1  having elongated body  11  and balloon  12  properly positioned for treating sinusitis of maxillary sinus  702 . The following discussion explains how the positioning shown in  FIG. 7B  is achieved. 
         [0048]    As shown in  FIG. 7C , catheter  1  is first positioned so it will articulate in a downwards direction from its non-articulated position. With catheter  1  properly positioned for downward articulation, the catheter distal end is positioned to enter the nasal cavity through nasal vestibule  509  as shown in  FIG. 7D . As shown in  FIG. 7E , the catheter  1  is advanced into the nasal cavity through nasal vestibule  509  so that balloon  12 , CCD camera  13 , and LED light  14  fully enter the nasal cavity. 
         [0049]      FIG. 7F  is an illustration of a view of the inside of the nasal cavity as seen using CCD camera  13 . As shown, the operator of the catheter  1  identities middle nasal turbinate  513  and nasal septum  516 . Inferior nasal turbinate  511  and middle nasal meatus  512  are shown and labeled for clarity. Having identified middle nasal turbinate  513  and nasal septum  516 , the operator advances the distal end of catheter  1  in the space at the side of middle nasal meatus  512  that is opposite of nasal septum  516  as identified as area  630 .  FIG. 7G  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 7F . 
         [0050]    Having advanced catheter  1  through area  630 , the operator uses CCD camera  13  to advance the distal end of catheter  1  until the ethmoidal bulla  610  is in view as shown in  FIG. 7H . The operator advances the distal end of catheter  1  past the uncinate process  611  and approaches the ethmoidal bulla  610  until nearly touching it. This movement entails moving towards the area  631 .  FIG. 7I  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 7H . 
         [0051]    Once the operator has advances the distal end of catheter  1  sufficiently close to the ethmoidal bulla  610 , the operator articulates the distal end of the catheter  1  in a downward direction and is then able to view the groove  612  between ethmoidal bulla  610  and uncinate process  611  as shown in  FIG. 7J . The operator advances the distal end of catheter  1  in this downward articulated state along groove  612  as also shown in  FIG. 6J .  FIG. 7K  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 7J . 
         [0052]    The operator advances the distal end of catheter  1  along groove  612  until the opening  701  of the maxillary sinus  702  is visible as shown in  FIG. 7L .  FIG. 7M  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 7L . Where other openings, sometimes called accessory ostia, other than the desired opening  701  exist in the same general area as opening  701 , the operator may need to observe the openings using the CCD camera  13  as shown in  FIG. 7L  and  FIG. 7M  in order to identify the correct ostium for insertion. Continuing to advance the distal end of catheter  1  toward the opening  701  of maxillary sinus  702 , the operator advances the balloon  12  into the ostium connecting maxillary sinus  702  to the rest of the nasal cavity as shown in  FIG. 7N . As depicted, the operator may need to articulate the distal end of catheter  1  as that distal end is advanced through the ostium so that the catheter  1  will continue advancing along the path of that ostium.  FIG. 7O  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 7N . In particular,  FIG. 7O  shows the inside of the maxillary sinus ostium and the opening  701  of the maxillary sinus  702  that exits the maxillary sinus ostium and enters the maxillary sinus  702 . As such, the image shows how the operator may view the opening  701  of the maxillary sinus  702  as he advances the distal end of catheter  1  through the maxillary sinus ostium.  FIG. 7P  is an image as seen through a CCD camera  13  while performing the movement as described with reference to  FIG. 7N , wherein the distal end of catheter  1  has been advanced through the maxillary sinus ostium and now is sufficiently advanced into the maxillary sinus  702  so as to allow the operator to view the interior wall of the maxillary sinus  702 . In some situations, it may be advantageous to advance the distal end of catheter  1  until it just enters the maxillary sinus  702 , and then use the camera advancement control  16  to advance just the CCD camera  13  and LED light  14  further into the maxillary sinus  702  in order to see the interior wall of the maxillary sinus  702  as shown in  FIG. 7P . 
         [0053]    Once balloon  12  is positioned between openings  701  of the maxillary sinus  702 , the operator changes balloon  12  to its expanded state as shown in  FIG. 7Q . This expansion is effective to correct the stenosis of the ostium. Once treatment by means of expansion is complete, the operator returns balloon  12  to its non-expanded state and removes it from the ostium. This removal may require articulation of the distal end of catheter  12  substantially in reverse of the articulation that the operator effectuated to allow the balloon  12  to enter the ostium. 
         [0054]    Once the balloon  12  is fully removed from the ostium, the operator can use CCD camera  13  to inspect the ostium in order to verify that the treatment was successful to correct the stenosis of the ostium as shown in  FIG. 7R . The operator then removes catheter  1  from the nasal cavity. 
         [0055]    According to the method of the present invention as above-described, the expansion body (balloon), particularly the effective expansive section of the expansion body (balloon) can be disposed over substantially the whole length of the stenosed part, so that the whole of the stenosed part can be pushed open when the expansion body (balloon) is expanded. According to the above-mentioned method, therefore, the stenosed part of the natural ostium can be pushed open more assuredly, so that a therapeutic effect on sinusitis can be enhanced. Besides, according to the above-described method, the catheter can be effectively prevented from being advanced excessively into the paranasal sinus cavity, so that safety in treatment of sinusitis can be enhanced. Furthermore, according to the method of the present invention, the expansion body in the inside of the nasal cavity can be positioned easily and accurately, and the stenosed part of the paranasal sinus cavity can be dilated assuredly and easily, by use of a simple device such as an endoscope, without using any special apparatus such as an X-ray apparatus. In addition, the method according to the present invention is a minimally invasive method based on the use of a catheter, which promises less-invasiveness to the patient. 
         [0056]    The present invention may be practiced or embodied in still other ways without departing from the spirit or essential character thereof. The preferred embodiments described herein are therefore illustrative and not restrictive, the scope of the invention being indicated by the appended claims and all variations which fall within the meaning of the claims are intended to be embraced therein.