Transrectal US in evaluation of patients after radical prostatectomy. Part I. Normal postoperative anatomy.

The appearance of the prostatic fossa on transrectal ultrasound (TRUS) scans obtained after radical retropubic prostatectomy (RRP) was studied in 25 patients believed to have no tumor on the basis of their level of serum prostate-specific antigen (PSA) (< or = 0.4 ng/mL). The profile of the vesicourethral anastomosis (VUA) in the midsagittal plane was tapered in 13 patients (52%) and nontapered in 12 patients (48%). The nontapered profile was associated with incontinence in nine of 11 patients (82%) followed up for less than 12 months but in only four of 14 patients (28%) followed up beyond 1 year. In 20 patients (80%), a hypoechoic soft-tissue lesion (average volume, 1.7 cm3) was seen anterior to the VUA and indented the anterior bladder wall. The length of the urethral high-pressure zone increased with muscular contraction of the pelvic floor. Knowledge of the baseline anatomic structures depicted on TRUS scans obtained after RRP may be useful in selection of tissue for TRUS-guided needle biopsy in patients with elevated levels of PSA. The many post-surgical changes reduced the specificity of the TRUS findings.