Abstract: A portable ultrasonic Doppler System for sensing movement, e.g. fetal heartrate, within a body. A handheld unit includes a housing containing an ultrasonic transmitter and an ultrasonic receiver. The ultrasonic receiver detects ultrasonic energy emitted from the ultrasonic transmitter and reflected off of the moving object being monitored. The handheld unit also includes a radio frequency transmitter for transmitting a carrier modulated in accordance with the response of the ultrasonic receiver. A radio frequency receiver unit, separate from the handheld unit, receives the signal broadcast by the handheld unit. The receiver unit drives a speaker or earphone to provide an audio output for listening to the moving object being monitored. Digital display and memory circuitry is also provided which can be used in conjunction with said receiver unit to store and display data indicative of the movement being monitored.

Abstract: A cryosurgical instrument which may be used with interchangeable spray and closed end cryotips includes a body member with a central bore extending partially therethrough. Refrigerant is supplied to a first point in the bore through a valved refrigerant supply line while an effluent opening connects an effluent line to a second point in the bore. The bore receives the inner ends of cryotips. All cryotips used with the instrument include refrigerant delivery tubes having inner ends which are positioned adjacent the first point in the bore and O-rings which are seated between the first point and the second point in the bore to prevent escape of refrigerant. Closed end cryotips to be used with the instrument further include an effluent channel extending from an expansion chamber to the second point in the bore. A second O-ring is provided with closed end cryotips.

Abstract: A cryosurgical instrument having a tip which is cooled by the Joule-Thomson expansion of a pressurized gas. The gas is conveyed to the tip by an inlet tube and exhausts through an exhaust tube connected to the rear of a fitting. The tip is connected to the forward portion of the fitting. The rear and forward portions of the fitting are rotatably connected by a bearing coupling which enables the tip to be rotated independent of the inlet and exhaust tubes.

Abstract: A cryosurgical instrument having a purge cycle of indeterminate duration, separate and apart from its cooling and warming modes, which can be conducted with a refrigerant consisting of a low pressure unsaturated or saturated gas. During the purge cycle, the pressure of the refrigerant gas is regulated to a level below that which is required to effect a Joule-Thomson expansion of the gas upon its entrance into an expansion chamber adjacent the tip of the instrument while simultaneously exhausting the effluent to the atmosphere through an exhaust valve actuated by a footswitch.