Hypoechoic rim of chronically inflamed prostate, as seen at TRUS: histopathologic findings

The purpose of this study is to correlate the findings of peripheral hypoechoic rim, seen at transrectal ultrasonography (TRUS) in chronic prostatitis patients, with the histopathologic findings.

Seven patients with pathologically proven chronic prostatitis were involved in this study. The conspicuity of the peripheral hypoechoic prostatic rim, seen at TRUS, was prominent and subtle, and to determine its histopathologic nature, the microscopic findings were reviewed.

In five of seven cases (71%), TRUS demonstrated a prominent peripheral hypoechoic rim. Microscopic examination revealed that inflammatory cell infiltration of prostatic glandular tissue was severe in three cases (42.9%), moderate in two (28.6%), and minimal in two (28.6%). In all seven cases, the common histopathologic findings of peripheral hypoechoic rim on TRUS were loose stromal tissues, few prostatic glands, and sparse infiltration by inflammatory cells.

The peripheral hypoechoic rim accompanying prostatic inflammation and revealed by TRUS reflects a sparsity of prostate glandular tissue and is thought to be an area in which inflammatory cell infiltration is minimal.