[Sonography of the prostate].

Transrectal ultrasound (TRUS) with a high frequency (about 7 MHz) probes offers imaging of the zonal anatomy of the prostate and the typical changes caused to it by diseases. The carcinoma is hypoechogenic and can be diagnosed by TRUS more often than by digital rectal palpation. Ventrally localized carcinoma can also be detected. Preoperative staging is more accurate than with any other method. TRUS-guided transrectal biopsy with semi-automatic biopsy systems is safe, has no complications and is more accurate than a digitally guided biopsy. The volume of an adenoma and its nature (benign/malignant) can be evaluated very precisely. Prostatitis and/or vesiculitis induce typical changes in echogenicity, so that these diseases can only be diagnosed by TRUS. However, good equipment still cannot yield reliable diagnoses unless it is operated by experienced examiners.