Trocar seal system

Valve assembly for sealed reception of an elongated object, which includes a valve body defining at least one opening configured and dimensioned to permit entry of the elongated object, a valve member formed of a resilient material and defining an aperture in general alignment with the opening of the valve body, the aperture being configured and dimensioned such that insertion of the object into the aperture causes the resilient material defining the aperture to resiliently engage the outer surface of the object in a substantially fluid fight manner and a manually rotatable control mechanism associated with the valve member to selectively open and close the aperture to permit entry of the object therethrough.

BACKGROUND OF THE INVENTION 
1. Field Of The Invention 
This invention relates to valve systems of the type adapted to allow the 
introduction of a surgical instrument into a patient's body. In 
particular, the invention is applicable to a cannula assembly and the like 
wherein a cannula extends from a valve assembly and is intended for 
insertion into a patient's body and an instrument is inserted into the 
patient's body through the cannula. 
2. Background Of The Prior Art 
Minimally invasive surgical procedures involve the introduction of surgical 
instruments into the body through small incisions and/or cannulas or 
trocar sleeves. Minimally invasive surgical procedures generally require 
that any instrumentation inserted into the body be sealed, i.e. provisions 
must be made to ensure that gases do not enter or exit the body through 
the incision or trocar sleeve as, for example, in surgical procedures in 
which the surgical region is insufflated. Moreover, minimally invasive 
surgical procedures often require the surgeon to act on organs, tissues, 
and vessels far removed from the incision, thereby requiring that any 
instruments used in such procedures be relatively long and narrow. 
For such procedures, the introduction of a tube into certain anatomical 
cavities such as the abdominal cavity is usually accomplished by use of a 
system comprised of a cannula assembly and a trocar. A cannula assembly is 
formed of a cannula or trocar sleeve attached to a valve assembly which is 
adapted to maintain a seal across the opening of the valve assembly. Since 
the cannula is in direct communication with the internal portion of the 
valve assembly, insertion of the cannula into an opening in the patient's 
body so as to reach the inner abdominal cavity should be adapted to 
maintain a fluid tight interface between the abdominal cavity and the 
outside atmosphere. 
Since minimally invasive surgical procedures in the abdominal cavity of the 
body require insufflating gases to raise the cavity wall away from vital 
organs, the procedure is usually initiated by use of a Verres needle 
through which a gas is introduced into the body cavity. Thereafter, a 
trocar, which is a sharp pointed instrument, is inserted into the cannula 
assembly and used to puncture the peritoneum, i.e. the inner lining of the 
abdominal cavity wall. The gas provides a slight pressure which raises the 
wall surface of the peritoneum away from the vital organs, thereby 
avoiding unnecessary contact with the organs by the instruments inserted 
into the cannula. This procedure also provides the surgeon with an 
adequate region in which to operate. Laparoscopic or endoscopic surgical 
instruments may then be inserted through the cannula to perform surgery 
within the abdominal cavity or other body portion. The cannula is also 
utilized for introducing tubes into the body as for drainage purposes or 
the like. 
In view of the need to maintain the atmospheric integrity of the inner area 
of the cavity, a valve assembly which permits introduction of a trocar or 
any surgical instrument and which permits selective communication of the 
inner atmosphere of the cavity with the outside atmosphere is desirable. 
In this regard, there have been a number of attempts in the prior art to 
provide such atmospheric integrity. 
U.S. Pat. No. 5,180,373 to Green et at. discloses a unique valve assembly 
which may be incorporated into a cannula assembly or utilized in 
combination with any type of tubular member for introduction into the body 
of a patient while permitting introduction of instruments into the body. 
The assembly disclosed in the Green et at. '373 patent includes a first 
valve formed of a resilient material and defining an aperture for 
reception of the object and a second valve positioned adjacent and distal 
of the first valve in general alignment therewith and defining an aperture 
in general alignment with the aperture of the first valve. A pair of 
manually operable clamps is provided to selectively permit the aperture of 
the second valve to be opened or closed so as to permit entry of the 
object such that the object first passes through the first valve and then 
the second valve prior to entry into the patient's body. The manually 
operable clamps enable the surgeon to selectively open or close the second 
valve in sequence and in a manner which positively retains the desired 
interface between the atmosphere on the inlet side of the valve assembly 
and the atmosphere outside the valve assembly. 
Although the valve assembly disclosed in the Green et at. '373 patent is 
effective for its intended purpose, the present invention is directed to 
another unique valve assembly for use in combination with a cannula 
assembly whereby opening of the valve mechanism for permitting entry of 
the surgical instrument may be readily achieved with an enhanced degree of 
control, i.e., by the rotation of a single control knob. 
SUMMARY OF THE INVENTION 
The present invention is directed to a valve assembly for sealed reception 
of an elongated object, which comprises a valve body defining at least one 
opening configured and dimensioned to permit entry of the elongated 
object, a valve member formed of a resilient material and defining an 
aperture in general alignment with the opening of the valve body wherein 
the aperture is configured and dimensioned such that insertion of the 
object into the aperture causes the resilient material defining the 
aperture to resiliently engage the outer surface of the object in a 
substantially fluid fight manner, and manually rotatable control means 
associated with the valve member to selectively open and close the 
aperture to permit entry of the object therethrough. 
The objects contemplated are surgical instruments such as clip appliers, 
dissectors, graspers, laser and electrocautery devices, drainage or fluid 
introduction tubes or the like. The valve body includes a neck which 
extends distally of the distal end thereof and which defines an opening 
communicating with the interior of the valve body. Further, the distally 
extending neck of the valve body is adapted to receive a tubular cannula 
such that the cannula extends distally of the valve body. 
In a preferred embodiment, the valve member is generally elongated and 
defines a proximal inlet portion, a distal outlet portion and an 
intermediate portion disposed between the inlet and outlet portions. The 
intermediate portion is capable of collapsing from a generally open 
position to a substantially closed fluid-tight position in the absence of 
the elongated object. Lever means is provided and positioned to engage the 
intermediate portion of the valve member and to collapse the intermediate 
portion such that the valve member assumes the substantially closed fluid 
fight position. The preferred lever means comprises a pair of opposed 
resilient lever members connected to respective lower and upper interior 
surfaces of the valve body. The lever members are resiliently biased 
towards each other and positioned to engage opposed surfaces of the 
intermediate portion of the valve member and collapse the intermediate 
portion to a configuration whereby the aperture is substantially closed. 
The manually rotatable control means includes camming means which is 
positioned and adapted to engage the opposed levers and displace the 
levers away from the intermediate portion of the valve member to permit 
the valve member to assume the generally open position. The camming means 
is mounted for rotational movement between a first position corresponding 
to the substantially closed position of the valve member and a second 
position corresponding to the generally open position of the valve member. 
The preferred camming means comprises a generally elliptical-shaped 
camming member defining a major axis greater in dimension than its minor 
axis. The camming member is mounted at its center to a rotatable rod, 
whereby rotational movement of the rotatable rod causes corresponding 
rotational movement of the camming member between the first and second 
positions. The camming member is positioned between the pair of opposed 
levers such that rotation thereof to the second position causes engagement 
with the pair of opposed levers and movement of the levers in a direction 
away from each other so as to be disengaged from the intermediate portion 
of the valve member to permit the valve member to assume the generally 
open position. The rotatable rod is preferably connected to a control knob 
which is manually rotatable by engagement by the user's fingers. 
The present invention is also directed to a cannula and trocar assembly for 
puncturing a patient's body wall for the introduction of elongated objects 
such as surgical instruments or the like into the body of a patient while 
maintaining a substantial fluid fight seal between internal body portions 
and the outside atmosphere. The assembly comprises a valve housing having 
an inlet opening at the proximal end and an outlet opening at the distal 
end, with the distal end opening having a tubular cannula extending 
distally therefrom. A trocar is positioned within the valve housing and 
the cannula. Thereafter, the trocar is removed and elongated objects such 
as surgical instruments or the like may be introduced into the patient's 
body through the valve assembly and cannula as described hereinabove.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) 
The present invention contemplates the introduction into a patient's body 
of all types of surgical instruments including clip appliers, lasers, 
photographic devices, tubes, etc. All such objects are referred to herein 
as "instruments". 
Referring initially to FIGS. 1 and 2, a cannula assembly 10 is illustrated 
having incorporated therein the novel valve assembly 12 constructed 
according to the present invention. Valve assembly 12 includes a valve 
housing 14 formed of upper housing half section 16 and lower housing half 
section 18 shown separated in FIG. 2 for convenience of illustration. 
The housing half sections 16, 18 are formed of a suitable desirable plastic 
material such as polycarbonate, polyethylene or the like. One preferred 
material is LEXAN.TM. brand polycarbonate manufactured and marketed by 
General Electric Company, Pittsfield, Mass. The housing half sections 16, 
18 are normally attached along the seam by suitable attachment techniques 
such as adhesive, ultrasonic welding, or the like. 
The valve housing 14 includes neck portion 20 at its distal end having an 
outlet opening 22 dimensioned for reception of an appropriate sheath tube 
such as cannula 24 to form the cannula assembly 10. The proximal end of 
valve housing 14 includes partition 26 having annular inlet opening 28. 
Partition 26 functions in supporting a diaphragm as will be described 
below. 
Referring now to FIG. 2, in conjunction with the cross-sectional view of 
FIG. 3, the novel inner valve assembly of the present invention will be 
described. Diaphragm 30 is generally elongated in shape and extends 
longitudinally through valve housing 14 between inlet opening 28 and 
outlet opening 22. The proximal end of the diaphragm 30 includes a 
circular flange 32 which fits tightly by a snap fit within a 
correspondingly dimensioned annular recess 34 formed on the proximal side 
of partition 26. The distal end of diaphragm 30 also includes a circular 
flange 36 which fits tightly about the periphery of the proximal end 
portion 38 of neck 20, which extends within the interior of the valve 
housing 14 as best shown in FIG. 3. 
Diaphragm 30 defines a longitudinal bore or aperture 40 for sealing 
reception of an instrument as will be described. The diameter of the bore 
40 gradually decreases towards the midportion 42 of the diaphragm 30 to 
form the hourglass configuration of the diaphragm as shown in FIG. 2. The 
dimension of bore 40 at constricted midportion 42 of the diaphragm is less 
than or equal to the outer diameter of the instrument intended for entry 
into the inlet opening 28 of the valve assembly 12. Diaphragm 30 is 
fabricated from an elastomeric material such as synthetic or natural 
rubber which is preferably sufficiently resilient to accommodate and 
provide a fluid seal with instruments of varying diameters, e.g., diameter 
of from about 5 mm to about 10 mm. The generally tapering configuration of 
proximal portion 44 of elongated diaphragm 30 facilitates entry of the 
instrument into the diaphragm. Similarly the generally tapering 
configuration of the distal portion 46 facilitates passage of the object 
through the diaphragm 30 and into the cannula 24. 
Referring now to FIG. 2, in conjunction with FIG. 4, a pair of opposed 
resilient levers 48, 50 are connected at their proximal end portions to 
the interior surfaces of upper and lower housing half sections 16, 18 
respectively. In particular, the proximal end portions of each lever 48, 
50 are snugly received within correspondingly dimensioned and positioned 
recesses 52, 54 (FIG. 2) formed in the respective interior surfaces of the 
upper and lower half sections 16, 18 to mount levers 46, 48 to the valve 
housing 14. Other methods for mounting levers 48, 50 may be readily 
determined by one skilled in the art. Levers 48, 50 extend generally 
longitudinally within valve housing 14 and have disposed therebetween 
diaphragm 30. Levers 48, 50 are normally biased in a direction towards 
each other and the central axis defined by valve housing 14 to engage 
opposed outer surfaces of the diaphragm 30 and collapse the diaphragm as 
best shown in FIG. 4. The levers are preferably fabricated from a 
resilient material such as stainless steel or the like. 
Referring now to FIGS. 2 and 4, in conjunction with the cross sectional 
view of FIG. 5, levers 48, 50 define planar engaging surfaces 56, 58, 
respectively, which engage the constricted midportion 42 of diaphragm 30 
to collapse this portion to form a substantially fluid fight seal between 
the proximal and distal ends of the diaphragm in the absence of a surgical 
instrument. The widths of engaging surfaces 56, 58 of levers 48, 50 are 
preferably greater than the diameter of constricted midportion 42 of 
diaphragm 30 as shown in FIG. 5 to ensure the bore 40 is completely closed 
in the manner depicted in the Fig. 
Referring now to FIGS. 2, 3, 5 and 6, the unique camming mechanism for 
opening the diaphragm 30 to permit the introduction of a surgical 
instrument through valve assembly 12 will now be described. Camming 
mechanism, identified generally by reference numeral 60, includes camming 
member 62, camming rod 64 and control knob 66. Camming member 62 is 
generally elliptical in shape having a major axis X greater in dimension 
than its minor axis Y. (FIG. 6) Camming member 62 is disposed between 
opposed levers 48, 50 and engagingly contacts camming surfaces 68, 70 
formed at the peripheral potions of levers 48, 50 in the manner shown in 
FIGS. 5 and 6. Camming rod 64 is securely connected to camming member 62 
and extends to the exterior of valve housing 14 where it is connected to 
control knob 66. Control knob 66 possesses a knurled surface to facilitate 
grasping by the surgeon. As will become appreciated from the description 
provided below, rotation of the control knob 66 causes corresponding 
rotation of camming rod 64 and camming member 62, which, in ram, causes 
displacement of the levers 48, 50 in a direction away from the central 
axis of valve housing 14 and from each other to permit elongated diaphragm 
30 to assume its normal open position. 
The operation of the valve assembly will now be described. The valve 
assembly is intended to be supplied as part of a cannula assembly, having 
a distal cannula tube 24 as shown in FIGS. 1 and 2. A trocar which is a 
sharp pointed instrument is usually fitted within a cannula assembly. The 
trocar is used to insert the cannula into a body cavity by first piercing 
the cavity wall (i.e., the peritoneum) and then introducing the cannula 
into the formed incision. Thereafter, the trocar is removed, permitting 
insertion of instruments into the patient's body through the cannula 24 to 
perform the desired procedure. Thus, the significance of providing control 
to the surgeon of the sealed state of the opening in the cannula assembly 
cannot be overemphasized. Such opening will ultimately control the 
exposure between the internal pan of the body cavity and the outside 
atmosphere. For laparoscopic procedures, the valve assembly will preserve 
the state of insufflation of the peritoneum during the surgical procedure. 
During the removal of the trocar from the cannula assembly, diaphragm 30 
closes automatically under the action of resilient levers 48, 50 which 
engage midportion 42 of the diaphragm and collapse the diaphragm as 
depicted in FIGS. 4 and 5. The surgeon may then insert an instrument into 
the body cavity by first inserting the instrument into inlet opening 28 
(FIG. 3) at the proximal end of valve housing 14 and then rotating control 
knob 66 to open diaphragm 30 to permit passage of the instrument through 
the valve housing. 
In the preferred embodiment, control knob 66 is rotated in a 
counterclockwise direction which causes corresponding counterclockwise 
rotational movement of rod 64 and camming member 62. As depicted in FIG. 
9, as camming member 62 rotates in the counterclockwise direction shown by 
the directional arrows, the elongated portion defined by its major axis X 
engages camming surfaces 68, 70 of levers 48, 50 and forces the levers 48, 
50 away from each other (as shown by the indicator arrows) towards their 
respective upper and lower half sections 16, 18. The particular slightly 
arcuate dimensions of camming surfaces 68, 70 accommodate the curved 
surfaces of camming member 62 during rotation of the camming member to 
ensure smooth movement thereof. Continued rotational movement causes 
camming member 62 to lift levers 48, 50 from their engagement with 
constricted midportion 42 of diaphragm 30 to permit the diaphragm 30 to 
assume its normal open position, thus enabling the passage of an 
instrument through diaphragm 30. FIGS. 7 and 8 illustrate diaphragm 30 in 
the open position with camming member 62 rotated to engage camming 
surfaces 68, 70 of levers 48, 50 so as to displace the levers away from 
the diaphragm. 
The instrument may then be passed through diaphragm 30 where the 
constricted bore or office defined at midportion 42 of diaphragm 30 forms 
a fluid tight seal about the periphery of the instrument, which, 
accordingly seals the inner body cavity from the outside atmosphere. This 
seal is provided by the resilient property of the stretched elastomeric 
material surrounding the orifice. Manipulation of the instrument in any 
direction will not affect the seal, since the elastomeric material 
defining the opening will conform to the movements of the instrument and 
assume an elliptical or other shape necessary to maintain contact. 
The constricted bore or orifice defined at midportion 42 of diaphragm 30 is 
preferably dimensioned between 3 and 15 mm to accommodate laparoscopic and 
endoscopic instruments such as clip appliers, laser tubes, photographic 
instruments, tubes or the like. However, depending upon need or 
application this dimensional range may be varied to accommodate any 
particular instrument. 
The opening of bore is always under the surgeon's control through control 
knob 62 and is adapted to be automatically actuated to the closed 
condition under action of resilient levers 48, 50 when the surgeon removes 
the instrument or other object from the valve assembly. Further, 
manipulation of the instrument does not affect the shape of diaphragm 30, 
or the sealing contact of the inner wall of the diaphragm with the 
instruments because the diaphragm is sufficiently flexible and resilient 
to maintain contact with the surface of the instrument. Thus, during the 
entire sequence, the integrity of the seal between the inside of the body 
cavity and the outside atmosphere is clearly maintained. 
To the extent not already indicated, it also will be understood by those of 
ordinary skill in the art that any one of the various specific embodiments 
herein described and illustrated may be further modified to incorporate 
features shown in other of the specific embodiments. 
The invention in its broader aspects therefor is not limited to the 
specific embodiments herein shown and described but departures may be made 
therefrom within the scope of the accompanying claims without departing 
from the principles of the invention and without sacrificing its chief 
advantages.