Ultrasonically induced morphological damage to mouse ovaries

Mouse ovaries were exposed in in vivo to 1 MHz continuous wave ultrasonic energy at spatial peak intensities ranging from 5 to 100 W/cm² for times varying from 300 to 15 s depending on the intensity. Following exposure the ovaries were surgically removed at times ranging from immediately (within 60 s) to 7 days and prepared histologically for light microscopic analysis. The observed tissue alterations varied from severe, at the higher intensities to subtle, at the lower intensities. Lesions were manifested by pyknosis of cells, vacuolization of cells and tissue, eosinophilic cytoplasm, and general cellular disruption. Subtle alterations showed large numbers of polyovular follicles and increases in the amount of PAS positive material in the interstitial tissue. Various ovarian structures showed differing sensitivities to the insult with luteinized structures being preferentially altered.