Ultrasonic measurement of the biomeciianical properties of the rabbit sclera

Purpose. An ultrasonic technique was used to quantify the age effect on the biomechanical properties of the rabbit sciera. Methods. Eight eyes were enucleated from 4 pigmented rabbits. Two of the 4 rabbits were 2 weeks old and two were 6 months old. Intraocular pressure was maintained between 7 and 10 mm Hg for each measurement. Immediately following enucleation, shear wave measurements were performed using a 5 MHz ultrasonic transducer attached to a fused silica buffer block. A pulser/receiver card was used to generate and detect the ultrasonic wave with analog to digital transformation performed by a data acquisition card. Results. The measured shear wave velocity (C,) for the two week old rabbits was 4Q.1±12.7 m/sec, and for the six month old rabbits was 71.7ÜO.S m/sec. The calculated Young's modulus (E) for the young and adult groups were (1.8±1.0)x 106 N/m2 and (5.2±1.6}xl06 N/m2, respectively (p < 0.001). Conclusions. The Young's modulus of 2 week old rabbit scieras is less than the 6 month old ones, which suggests the elasticity of the sciera changes with the age of the rabbit.