5C-1 Ultrasonic Microprobe Based Tubular Size Assay

We report on a microfabricated silicon microprobe integrated with an ultrasonic actuator and polysilicon strain gauges for microdissection testicular sperm extraction (TESE) surgery. Insertion experiment was performed on rat testis tissue and by monitoring the tubule puncture artifact in the force signal sensed by the microprobe, we were able to estimate the average diameter of the sperm-carrying tubules in the sample. We have demonstrated the ability to sense the existence of larger tubules embedded in a mess of thinner tubules, using an analytically calculated expression for the distribution of sizes measured by the microprobe. This information is important in microdissection TESE to distinguish tubules with and without fertile sperm, potentially eliminating the large incision currently required for optical spermatazoa localization.