Percutaneously insertable, needle-sized tissue retractor and system

#This invention relates to surgical instruments and particularly to a needle-sized tissue retractor and system that are percutaneously inserted into a cavity of a subject.

#Minimally invasive endoscopic surgery is performed using two or more trocar sheaths for gaining access to a cavity of a patient. These trocar sheaths provide access to the surgical site for various medical instruments such as forceps, scissors, and scopes. The advantages of endoscopic surgery over traditional, open surgery include decreased trauma for the patient, smaller wounds and less scarring, faster healing and recovery time, and decreased risk of infection.

#A problem presented by endoscopic surgical procedures is that a surgeon has no direct visualization of the surgical site. Instead, visualization of the surgical site is by a video camera and monitor. The surgeon uses medical devices inserted through access sheaths to manipulate tissue adjacent the surgical site for lifting tissue out of the line of sight. A solution to this problem is the use of an additional access sheath for inserting forceps or a grasper to the surgical site for retracting tissue. A limitation of using these sheaths, however, is that the trocar sheaths normally range in size from 3 to 10 mm and leave deep, cylindrical wounds where a significant bulk of tissue is removed. As a result, surgeons tend to use as few access sheaths as possible.

#FIG. 1 depicts an illustrative percutaneously insertable, needle-sized retractor and system of the present invention; and

#FIG. 2 depicts an enlarged, partially sectioned, side view of the retractor of FIG. 1.

#Depicted in FIG. 1 is an illustrative percutaneous retractor system 100 comprising needle-sized trocar sheath 101, tissue retractor 102, and trocar stylet 103 for percutaneous insertion into the cavity of a patient. The trocar sheath comprises a polytetrafluoroethylene radiopaque material tube 104 having passage 105 extending longitudinally therethrough. Tube 104 has an outside diameter in a range of 10 to 22 gauge (0.028" to 0.134") and is approximately 13 cm in length. Preferably, tube 104 has an 8 French (0.105") outside diameter and a wall 106 thickness of approximately 0.016". Fixedly attached using, for example, medical grade adhesive about proximal end 107 of the tube are well-known male and female Luer lock connector adapters 108 and 109. Also positioned about the proximal end of the tube is retention cap 110 threadably engaging female connector adapter 109. Passage 111 extends through the retention cap and connector adapters to communicate with passage 105 of the polytetrafluoroethylene tube. Trocar stylet 103 is inserted through passages 105 and 111 of the tube and retention cap. When the trocar stylet is fully inserted in tube 104, pointed distal end 112 of the stylet extends distally from passage 105 of the tube. The trocar sheath with the pointed distal end of the stylet extending therefrom is then percutaneously inserted into the cavity of a patient through the skin and subtending tissue and organs. The trocar stylet stiffens the sheath for advancement through the skin and subtending tissues and organs. A well-known connector cap 113 is fixedly positioned about a proximal end 114 of the stylet with, for example, medical grade adhesive for positioning and manipulating the stylet with respect to the trocar sheath. The trocar stylet preferably comprises a stainless steel material rod approximately 17 cm in length with an outer diameter of approximately 0.068". The distal end of the rod is ground to a point for easy insertion into the cavity of a patient.

#When the trocar stylet and sheath are inserted into the cavity of a patient, the stylet is removed from the passage of the sheath. Tissue retractor 102 is then inserted through the passage of the trocar sheath and into the cavity of the patient. The retractor includes grasper 115 positioned at distal end 116 of elongated member 117. Tissue retractor 102 also comprises push-button handle 118 attached about proximal end 119 of elongated member 117. Handle 118 is grasped by the middle and index fingers along with the thumb of the physician to operate pivotedly interconnected jaws 120 and 121 of grasper 115 between open and closed positions. Jaws 120 and 121 have well-known alligator teeth for grasping tissue or, alternatively, a well-known hounds tooth configuration. Normally, the grasper is maintained in the closed position with jaws 120 and 121 engaging one another. The jaws of the grasper are operated to the open position by the physician pressing push-button piston 122 of the handle which slidably moves in enclosure 123 of the handle. Retaining cap 110 of the trocar sheath includes seal 124 positioned about passageway 111, which is compressed to engage elongated member 117 of the retractor. This is accomplished by the physician turning retention cap 110, compressing the seal, and fixedly positioning the retractor in passages 105 and 111 of the trocar sheath and retention cap.

#The retractor system further comprises a well-known retention flange 125, such as the Molnar retention disk commercially available from Cook Urological, Incorporated, Spencer, Ind. The disk includes passage 126 of which trocar sheath tube 104 is inserted therethrough. The disk is moved along the length of the tube to engage the surface of the skin and fixedly position the trocar sheath with respect to the cavity. With the retention cap fixedly positioning the grasper, and the retention flange fixedly positioning the trocar sheath with respect to the surface tissue of the patient, the grasper can effectively grasp, retract, and fixedly position tissue during a minimally invasive endoscopic procedure.