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The elastic modulus (Cii) of the cortical bones of 19 individuals (14 femurs and 16 tibias, fixed in formalin) was determined ultrasonically. Elastic moduli were measured at four anatomical positions (anterior, posterior, medial and lateral) and in all three planes of orientation (transverse, longitudinal and radial). The mean tibial Cii (34.11 GPa) was greater than that obtained for femurs (32.52 GPa). The tibial longitudinal plane Cii (34.1 GPa) was significantly greater than the femoral longitudinal plane Cii (32.5 GPa). Cii was significantly higher in the tibia than the femur in both the medial and posterior anatomical positions. The anterior tibia had a significantly lower C11 compared to other positions. Cii was significantly higher in the longitudinal plane than the transverse or radial planes in both the femur and the tibia. There was no consistent difference in modulus between left and right sides. No age effects were observed. There were no significant differences between males and females, or between African Americans and European Americans.

In this study, we employed a high-frequency ultrasound system to measure the epidermal thicknesses of psoriasis plaques and normal skin in vivo. Eighty-four percent of the ultrasound measurements fell within the range of epidermal thickness determined by histology. The average thickness of untreated psoriasis measured by ultrasound was significantly greater than that of either treated psoriasis or normal skin. Ultrasound measurement of thickness was consistent with clinical assessment. Ultrasound measurements also demonstrated known variations in epidermal thickness by body site. Further development is needed to obtain measurements that are fully representative of the epidermis.

A small-aperture, prototype ultrasonic imaging system, typical of the size necessary to be embedded in a catheter, was developed to evaluate the feasibility of intravascular ultrasonic imaging catheters (UICs). The evaluation included in vitro imaging of postmortem samples of human femoral and iliac arteries with the UIC prototype and a high-resolution magnetic resonance (MR) proton imager. Excellent correlations between results from the UIC images, MR images, and tissue specimens were demonstrated. Although the current prototype is too large to be useful in examination of smaller vessels such as coronary arteries, the signal-to-noise ratio and resolution obtained indicate that imaging with intravascular UICs is feasible and may have significant diagnostic value.