| abstract |
Preferred transducers in the substantial shapes of a three-dimensional bodies, normally spheres or cylinders, emit ultrasound omni-directionally. The transducers are secured to the wall of the cervix uteri of human female, preferably by a barb or corkscrew coil, so that a straight line ultrasonic acoustic path exists between them. An ultrasonic transit time sonomicrometer detecting a variable propagation delay between the transducers dependent upon the dilatation or effacement of the cervix uteri serves as a ultrasonic cervimeter. Cervical dimension, and changes in dimension, developed by the ultrasonic cervimeter directly in millimeters are (i) validated for reasonableness, (ii) monitored so as to generate several alarms upon the occurrence(s) of several predetermined conditions, (iii) displayed, and (iv) archived all in a battery-powered ambulatory instrument. |