Transrectal prostatic ultrasonography: comparison of linear array and radial scanners.

Transrectal ultrasound probes can image the prostate only in a single plane. A retrospective study was undertaken to evaluate the capabilities and differences of longitudinal and transversely oriented images obtained from transrectal sonographic examinations. The patients were studied by both modalities using commercially available machines. Comparisons of the images demonstrated that the transverse image yielded more information about the lateral margins of the prostate; the longitudinal image showed the apex and base more clearly; prostatic calculi, which can be confused with other pathologic processes, were more accurately identified by the longitudinal scanners; and both techniques adequately demonstrated the abnormality, particularly cancer, although some lesions were seen better on either one or the other orientation. Either scanner can be used for a satisfactory study, but both methods may have to be utilized to conduct a thorough evaluation of the prostate and surrounding structures.