Comparison of magnetic resonance imaging to ultrasound for prostate sizing.

INTRODUCTION: To compare pelvic ultrasound (PUS) and transrectal ultrasound (TRUS) to magnetic resonance imaging (MRI) in the estimation of prostate size. MATERIALS AND METHODS: After IRB approval, we performed a single-center, retrospective study of 91 patients who had prostate sizing between August, 2013 and June, 2017. Correlation, reliability, and agreement between PUS, TRUS, and MRI were calculated through the Pearson coefficient, intraclass correlation coefficient, and Bland-Altman analysis, respectively. Data was stratified by prostate size, body mass index, and time between imaging acquisition. RESULTS: A total of 91 patients underwent all three imaging methods. Median age was 64, median body mass index (BMI) was 27 kg/m2, and median PSA value prior to PUS was 7.1 ng/mL. Pearson coefficient for MRI versus TRUS and MRI versus PUS was 0.90 and 0.87, respectively. Intraclass correlation coefficient was 0.90 (0.87-0.93) comparing all three modalities. BA analysis for MRI versus TRUS and MRI versus PUS showed that for prostates ≤ 50 cc, greater than 79% of the data fell within limits of agreement. Percentages decreased with increasing prostate size to 46% and 41% for prostates > 50 cc and ≤ 80 cc and to 28% and 25% for prostates > 80 cc for MRI versus TRUS and MRI versus PUS, respectively. CONCLUSIONS: MRI may be considered clinically interchangeable with TRUS and PUS for prostate sizing at prostate volumes ≤ 50 cc. For larger prostates and when minor changes in prostate size would drastically alter surgical management, cross-sectional imaging should be considered.

Transurethral resection of prostatic abscess.

Prostate abscess (PA) is an uncommon prostatic infection, with risk factors including indwelling catheters, acute or chronic prostatitis, bladder outlet obstruction, voiding dysfunction, recent urologic instrumentation (especially transrectal prostate biopsy), chronic kidney disease (CKD), diabetes mellitus (DM), human immunodeficiency virus (HIV), intravenous drug use (IVDU), and hepatitis C. Treatment of PA consists of antibiotics and abscess drainage via transurethral resection (TUR) or image-guided transrectal or transperineal drainage. Numerous studies have demonstrated that TUR of PA has a higher success rate and shorter hospital length of stay when compared to image-guided drainage. Despite this, TUR of PA is a relatively uncommon surgery with few useful recommendations on how to best perform this procedure. We demonstrate the TUR surgical technique for drainage of a 6 cm loculated PA in a 44-year-old man with active IVDU and hepatitis C. The patient presented with progressive voiding symptoms, urinary retention, and leukocytosis. Given the size, loculated nature of the abscess, and its proximity to the prostatic urethra, we decided to proceed to the operating room for surgical drainage as opposed to image-guided transrectal drainage. Herein we describe the trans urethral technique. He clinically improved postoperatively and repeat imaging 4 days later showed decreased abscess size. Transurethral drainage of a PA is a safe, efficient, and effective treatment option. Treatment approach should depend on abscess size, location, and presence of loculations. Combining different endourologic techniques and instruments may be necessary.

Comparison of Transabdominal and Transrectal Ultrasound for Sizing of the Prostate.

OBJECTIVE: To compare the accuracy of prostate sizing between pelvic abdominal (PUS) and transrectal (TRUS) ultrasound in a large, diverse cohort of men at our institution. Prostate volume plays a vital role in all types of prostate disease. American Urological Association guidelines (2018) for surgical management of benign prostatic hyperplasia now include consideration of prostate volume measurement prior to surgical intervention. Ultrasound is a quick and radiation-free imaging modality. METHODS: We performed a single-center, retrospective study of 299 patients with prostate sizing between January 1, 2012 and August 31, 2017. Prostate volume was derived from ellipsoid volume calculation using dimensions measured on ultrasound. PUS and TRUS were compared by calculating the Pearson correlation coefficient and intraclass correlation coefficient, and agreement between modalities assessed using the Bland Altman analysis. This analysis was done for the whole sample population as well as for specific groupings according to body mass index, prostate size, and time between exams. RESULTS: A total of 236 patients had PUS followed by TRUS and met study inclusion criteria. Median age was 63, median prostate specific antigen value prior to PUS was 7.6 ng/mL, and only 20% were white. Mean volume differences between the two modalities for the data (volPUS - volTRUS) were (-0.3 ± 1.1) cm3. Bland-Altman analysis showed agreement between PUS and TRUS only for prostates ≤ 30 cm3. CONCLUSION: For prostates less than 30 cc, we found that PUS is interchangeable with TRUS in estimating prostate volume. However, for larger prostates where size may alter surgical management, we would recommend TRUS or cross-sectional imaging.