Abstract: A hand held endoscopic viewing system including a viewing assembly, an eyepiece assembly, and a handle is disclosed. The components are releasably mounted for ease of use and cleaning. The viewing assembly incorporates a fiber optic image bundle for carrying an image to the eyepiece assembly. The proximal end of the image bundle terminates in a coupling assembly that couples the eyepiece assembly to the viewing assembly such that the proximal end of the image carrying bundle is held against a window on the eyepiece assembly. The eyepiece assembly includes focusing optics that define a focal plane at the distal plane of the window for focusing and magnifying the image that is carried to the proximal end of the image bundle. The handle includes a light source and a power source and supports the eyepiece assembly and the viewing assembly at two points.

Abstract: A viewing system for use with a breathing tube such as an endotracheal intubation tube or a tracheostomy tube and a viewing assembly having a viewing conduit for indirectly viewing the tracheal area of a patient into which the breathing tube is being inserted and for guiding the tube into place within the patient's trachea is disclosed. The viewing system also incorporates an adapter handle which allows the viewing assembly to be used with breathing tubes of varied lengths.

Abstract: A hand-held viewing system for use during medical procedures including endotracheal intubations or tracheostomies is disclosed. The viewing system includes an endoscope assembly having a fiber optic bundle for indirectly viewing the tracheal area of a patient into which the breathing tube is being inserted and a malleable sheath on the endoscope assembly for guiding the tube into place within the patient's trachea. The viewing system also incorporates an adapter stop which allows the endoscope assembly to be used with breathing tubes of varied lengths. A handle is included to which the endoscope assembly and a viewing means are removably connected.

Abstract: A surgical instrument incorporating visualizing optics is disclosed. The instrument comprises a handle supporting a rigid hollow shaft, an expanded tip is located on the distal end of the shaft providing a surface that will not tear or easily penetrate tissue. A fiber-optic assembly, containing at least one illumination transmitting fiber, a plurality of image-carrying fibers and an objective lens mounted near the distal end of the image fibers runs the length of the shaft. The objective lens is positioned relative to an opening in the tip allowing viewing. Light for illuminating the surgical site passes through one or more illumination fibers and through the opening in the tip of the probe. Light reflected from the tissue at the tip of the probe is focused onto the distal face of the image bundle by an objective lens and is then transmitted to the proximal end of the image bundle.

Abstract: A kit is provided including at least one fiber-optic bundle of the type including a plurality of flexible image fibers having an objective lens attached to one end and a connector attached to the other end. The connector is adapted to mate with a viewing device. A coating of a pressure-sensitive adhesive is also provided to secure the fiber-optic bundle to a selected one of a variety of instruments with the fiber-optic bundle conforming to the profile of that instrument over substantially the entire length with the objective lens positioned so as to include the working element of the instrument in the field-of-view. A positioning device is used to position the objective lens to ensure proper focus. The components of the kit are contained in a sterilizable enclosure which includes a bottom tray and a top cover which may be formed of a spun-bonded polyolefin fiber material.

Abstract: A surgical instrument incorporating visualizing optics is disclosed. The instrument comprises a handle supporting a rigid, curved, hollow shaft, a spherical tip is located on the distal end of the shaft providing a surface that will not tear or easily penetrate tissue. A fiber-optic assembly, containing at least one illumination transmitting fiber, a plurality of image-carrying fibers and an objective lens mounted near the distal end of the image fibers runs the entire length of the shaft. The objective lens is mounted relative to an opening in the tip allowing either axial viewing or side viewing. Light for illuminating the surgical site passes through one or more illumination fibers and through the opening in the spherical tip of the probe. Light reflected from the tissue at the tip of the probe is focused onto the distal face of the image assembly by an objective lens and is then transmitted to the proximal end of the image assembly.

Abstract: A flexible endoscope have a force limiting coupler. The endoscope comprises an elongated tubular member having a proximal end, a distal end and a wall defining a lumen extending there through. A handle member is fixed to the proximal end of the tubular member. The handle member has a slidable knob member which is coupled to a force limiting means to limit the travel of the knob member. A deflection wire is coupled at one end to the force limiting means and a second end to the distal end of the tubular member. The force limiting means has a predetermined spring constant. The distal end of the endoscope can be deflected in finer increments and acts to preclude potentially damaging forces to be applied to the endoscope or to tissue.

Abstract: A generating circuit for producing atrial and ventricular timing signals for a pacemaker which allows independent control of ventricular rate and atrial-ventricular delay. A voltage ramp signal is generated and compared to a reference voltage signal by a voltage comparator which produces an output signal when the ramp voltage reaches the reference voltage. A second voltage comparator compares the reference voltage with a second ramp voltage signal which is generated by offsetting the first voltage ramp signal so that the second ramp signal parallels and leads the first voltage ramp signal by an offset voltage difference. The second voltage comparator produces a second output signal when the second ramp voltage signal equals the reference voltage. Alternatively, the second output signal can be produced by offsetting the reference voltage signal and comparing it to the voltage ramp signal in the second comparator. The first and second output signals provide atrial and ventricular timing signals.

Abstract: Apparatus and method for accurately measuring the energy output of a pacing system analyzer or other pulse generator. Voltage measurements are made across the output capacitor before and after the pulse is generated. These voltages are measured by a microprocessor using an analog-to-digital converter and various gating and control circuitry. By using a known value of capacitance for the output capacitor along with the voltages measured before and after the stimulation pulse is generated, the microprocessor can calculate the total amount of energy within the stimulation pulse. This value is displayed on an integral display device. Through the use of additional circuitry, measurements may be made for both atrial and ventricular stimulation pulses in a dual chamber stimulation device. Provisions have also been made for measuring the output energy for constant voltage pulse generators. This technique employs measurement of pulse width.

Abstract: A digital computer system is described as comprising an input data circuit, a processor for executing a program stored in a memory to process the inputted data, a depletable energy source (e.g., a battery) for energizing the elements of the computer system, and a power control circuit for selectively controlling the drain imposed upon the energy source in accordance with the data input into the system and the program executed by the processor. In an illustrative embodiment of this invention, the power control circuit is operative in at least three modes of operation, namely off/rest, power down, and operating. In the off/rest mode, the power control circuit imposes a minimum power drain upon the depletable energy source. An operator may manipulate a switch or actuation means to apply a transition signal to the power control, whereby the computer system is disposed from its off/rest mode to its power down mode.

Abstract: An atrial-ventricular demand pacemaker having improved atrial pulse artifact rejection includes a blanking circuit (30, 100) connected in the signal path from the ventricular output terminal (17) to the sensing amplifier (21) to blank the signal during an atrial pulse. A holding circuit including a low-pass filter (46, 137) and a switching element (43, 112) stores a prior signal value at the sensing amplifier input during the blanking interval, and delays return to normal operation until after the blanking circuit has returned to normal. Artifact rejection is also improved by limiting atrial pulse output circuit recharge time and by limiting polarization current driven into the ventricular output circuitry by an atrial output pulse.

Abstract: Apparatus is disclosed for sensing and transmitting the stimulating pulse of an implanted pacemaker over readily available, low-bandwidth transmission media to a remote receiver capable of measuring the pulse width to provide an indication of the condition of the pacemaker energy source, e.g. a battery. In particular, the sensing and transmitting apparatus detects the electrical activity, e.g. the EKG, of a patient through attached electrodes and modulates a carrier or tone of a suitable frequency to be transmitted over the low-bandwidth transmission medium to the receiver, along with a pulse signal multiplied by a selected, fixed factor dependent upon the carrier frequency of the signal and the other information to be transmitted to the receiver.

Abstract: An atrial-ventricular demand pacemaker having improved atrial pulse artifact rejection includes a blanking circuit (30, 100) connected in the signal path from the ventricular output terminal (17) to the sensing amplifier (21) to blank the signal during an atrial pulse. A holding circuit including a low-pass filter (46, 137) and a switching element (43, 112) stores a prior signal value at the sensing amplifier input during the blanking interval, and delays return to normal operation until after the blanking circuit has returned to normal. Artifact rejection is also improved by limiting atrial pulse output circuit recharge time and by limiting polarization current driven into the ventricular output circuitry by an atrial output pulse.