Review on ultrasound measurement of bladder or detrusor wall thickness in women : techniques, diagnostic utility and use in clinical trials

Purpose To provide a narrative review of literature evaluating ultrasound techniques for the measurement of bladder wall hypertrophy in women as an alternative to invasive urodynamic assessment for the diagnosis of lower urinary tract symptoms (LUTS). Methods A literature review was performed using PubMed and all paper journals of congress abstracts searching for articles on ultrasound measurement of bladder wall thickness (BWT) or detrusor wall thickness (DWT) published between January 1990 and May 2012. Each study was classified with a level of evidence using the Oxford Centre for Evidence-based Medicine classification (2009). Results Ultrasound measurement of bladder wall hypertrophy is not standardised, and techniques vary widely according to anatomical approach, ultrasound frequency and other factors. This review compared transvaginal, translabial/transperineal and suprapubic approaches for ultrasound BWT/DWT measurement. BWT/DWT measurements correlated well with urodynamic diagnoses of detrusor overactivity (DO) using all three ultrasound techniques. BWT values were consistently higher in women with DO than in women with stress incontinence, although threshold values for the differential diagnosis of DO varied between clinical studies (5.0–6.5 mm using transvaginal ultrasound). Few data were available on the use of translabial or suprapubic ultrasound in women. Inter- and intraobserver variability was higher with transperineal and suprapubic ultrasound, and these techniques appear less reliable than transvaginal ultrasound. Studies suggest that BWT is reduced in response to antimuscarinic therapy in women with overactive bladder or DO. Conclusions Data from clinical trials suggest that transvaginal ultrasound measurement of BWT is a reliable method of diagnosing DO in women with LUTS, and BWT decreases during antimuscarinic therapy