Abstract: An endoscopic stapler includes a stapling head which is removably locatable on the distal end of an endoscope. The stapling head includes a stationary part which houses a removable staple cartridge and a movable part which includes an anvil for receiving and bending the ends of staples fired from the stationary part. The staple cartridge preferably houses two semi-circular rows of staples which are staggered relative to each other. The movable part is coupled to the stationary part by a threaded shaft which engages a worm gear in the stationary part and a first rotatable control wire is coupled to the worm gear. A substantially semi-circular firing cam is located proximal of the staple cartridge in the stationary part. The firing cam has an interior splined surface which is engaged by a spline gear coupled to a second rotatable control wire. In one embodiment, a knife is coupled to the firing cam so that tissue is cut subsequent to stapling.

Abstract: A tissue core biopsy cannula of the present invention includes a distal end which is ground in two planes which intersect each other at a first angle along a line which intersects the longitudinal axis of the cannula at a second angle. This produces a cardioid shaped opening in the distal end of the cannula. The entire edge of the sidewall is thereby inclined inward toward the distal opening and two distal cutting edges are provided. According to the presently preferred embodiment, the first angle at which the two planes intersect is approximately 60.degree. and the second angle at which the intersection of the two planes intersects the longitudinal axis of the cannula is approximately 20.degree.. In order to aid in removal of the biopsy sample from the target tissue site, the cannula according to the invention is provided with side fenestration holes and/or a split end which aids in grasping the tissue so that it can be pulled away from the target tissue site.

Abstract: A protected microbiological sampling brush assembly includes a sampling brush mounted on the distal end of a control wire, an inner catheter which houses the brush, an outer catheter which houses the inner catheter, and an elastomeric tip which is rigidly attached to the distal end of the outer catheter and which has a weakened end. The proximal ends of the control wire and catheters are coupled to a handle for independently moving the control wire, the inner catheter, and the outer catheter relative to each other. The weakened end of the elastomeric tip is preferably a slit which defines lips which are parted when the distal end of the inner catheter is moved distally against the elastomeric tip to allow the inner catheter to pass therethrough. When the inner catheter is moved proximally relative to the outer catheter, the lips of the elastomeric tip close to protect the inner catheter (and the sampling brush) from contamination.

Abstract: An air introduction system for a medical needle assembly is provided and includes a flexible bladder, and a male luer assembly with an air valve which is biased to allow air to enter the air introduction system but not to exit. The air introduction system is coupled to a needle assembly which is to be introduced into the epidural space. As the needle traverses the tissue layers overlying the epidural space, and the practitioner applies pressure to the bladder, the practitioner experiences resistance to the forcing of air through the needle assembly. If air is lost from the bladder, the bladder may be refilled by releasing the pressure on it and allowing outside air to enter via the air valve. Once the epidural space is penetrated, air is quickly forced from the bladder through the needle assembly and the practitioner can feel a sudden drop in pressure.

Abstract: A tissue core biopsy cannula of the present invention includes a distal end which is ground in two planes which intersect each other at a first angle along a line which intersects the longitudinal axis of the cannula at a second angle. This produces a cardioid shaped opening in the distal end of the cannula. The entire edge of the sidewall is thereby inclined inward toward the distal opening and two distal cutting edges are provided. According to the presently preferred embodiment, the first angle at which the two planes intersect is approximately 60.degree. and the second angle at which the intersection of the two planes intersects the longitudinal axis of the cannula is approximately 20.degree.. In order to aid in removal of the biopsy sample from the target tissue site, the cannula according to the invention is provided with side fenestration holes and/or a split end which aids in grasping the tissue so that it can be pulled away from the target tissue site.

Abstract: An endosurgical cutting instrument includes a hollow tube having a distal end with a radial slot and an interior deflection surface, a push rod extending through the tube and having a proximally directed sickle blade coupled to its distal end, and a manual actuator coupled to the proximal ends of the tube and the push rod for imparting relative axial movement to the tube and push rod. The sickle blade is a curved member having a sharp concave edge and a dull convex edge and is coupled to the distal end of the push rod with its sharp concave edge facing the push rod. The blade is dimensioned such that it may be substantially completely contained within the tube. The push rod is oriented so that its distal end is free to move in a radial direction as it moves axially. Movement of the push rod against the deflection surface urges the push rod in a radial direction thereby causing the sickle blade to exit the tube through the radial slot.

Abstract: An apparatus for counting the number of times a temperature cycle occurs includes an indicator having sequential indicia and a temperature responsive member for indicating a next one of the indicia. Mechanical, fluid mechanical and electronic versions of the invention are disclosed. In the mechanical version, the indicator can be a ratchet member having teeth, a pawl and a display surface containing indicia. A temperature responsive element such as a bimetallic member engages the teeth of the ratchet and advances the ratchet each time the apparatus is subjected to a preset temperature cycle. A housing with a window masks the display to indicate one of the indicia as advanced by the temperature responsive element. Preferred embodiments of the mechanical version include a ring-like ratchet member with interior teeth and an exterior display surface.

Abstract: An endoscopic tool for dispensing units of hemostatic agent broadly comprises a hollow tube which holds a plurality of individual units of the hemostatic agent, a valve at the distal end of the hollow tube which permits the hemostatic agent to pass therethrough but prevents foreign matter from contacting the hemostatic agent while in the tube, a plunger which extends into the hollow tube and contacts a proximal unit of the hemostatic agent, and a mechanism for moving the plunger distally in incremental movements to cause, upon each incremental movement, an individual unit of the hemostatic agent to be pushed through the valve. Typically, the mechanism for moving the plunger and the proximal end of the hollow tube are held in a handle. One mechanism for moving the plunger utilizes a portion of the plunger as a ratchet by forming a plurality of conical elements thereon, and utilizes a switch in the handle which has a V-spring coupled thereto as a pawl for advancing the conical elements.

Abstract: An algorithm for ordering selects for a plurality of channels to be multiplexed into a frame is provided. The channel select position counter for each of the channels to be multiplexed are initialized. The first and succeeding channel selects are chosen based on the lowest price (highest cost) ready channel, with the price of a channel being equal to the value of the channel select position counter divided by the number of selects for that channel in the frame, and the readiness of the channel being indicated either by an indicator, or by the relative value of the position counter to the initial value of the position counter. Where channel prices are equal, the select is chosen on the secondary basis of channel rate, with the highest rate channel contributing first. After a select is made, the position counter of the selected channel is increased by the total number of selects in the frame.