Non-invasive ultrasound measurements in male patients with LUTS and benign prostatic obstruction. Implication for diagnosis and treatment

BACKGROUND: To evaluate the role of the ultrasound assessments of the bladder/detrusor wall thickness (BWT/DWT) and the ultrasound estimated bladder weight (UEBW) in lower urinary tract symptoms diagnosis and treatment. EVIDENCE ACQUISITION: A systematic literature search from January 1995 until February 2016 was performed on PubMed using the following terms: "bladder weight", "bladder wall thickness", "detrusor wall thickness", "LUTS", "bladder outlet obstruction" (BOO), "benign prostatic obstruction". Additional references were obtained from the reference list of full-text manuscripts. Abstracts presented at the annual congresses of the European Association of Urology, American Urology Association and the International Continence Society were also included. EVIDENCE SYNTHESIS: BWT and DWT are accurate predictors of BOO. Despite several differences in the technique assessment, population characteristics and study design, the BWT/DWT accuracy for BOO was close to 90%. Furthermore, the ultrasound evaluation of bladder/detrusor thickness correlates positively with symptoms score and the main clinical parameters in BPH patients. Lastly, BWT and DWT have proved to be optimal predictor of response to medical/surgical treatment of lower urinary tract symptoms/benign prostatic obstruction (LUTS/BPO). However, the lack of standardization among the available studies marks these methods promising but still experimental and further studies are needed to clarify the standard methodology. CONCLUSIONS: The ultrasound evaluation of bladder/detrusor thickness appears to be simple, highly accurate and non-invasive technique to predict BOO and to evaluate the clinical outcomes after medical/surgical treatments for LUTS/BPH. The implementation of these techniques and their standardization will probably better define their role in the diagnostic algorithms of patients with LUTS and possibly reduce the number of unnecessary pressure flow-studies.