The promise of bladder wall thickness as a useful biomarker for objective diagnosis of lower urinary tract dysfunction

Clinical diagnosis of lower urinary tract dysfunction (LUTD), such as bladder outlet obstruction (BOO) or overactive bladder (OAB), is usually based on presenting symptoms. A biomarker for objective diagnosis of these LUTDs is mandatory. Detrusor wall thickness (DWT) has been noted to be increased in men with BOO and children with bladder-induced enuresis. Patients with OAB are also found to have thicker DWT compared with controls. Although clinical studies using transabdominal or transvaginal ultrasound examination have reported a thicker DWT in patients with BOO or OAB, the reported data are not consistent and lack standardization. We believe that DWT is a promising biomarker for objective diagnosis of LUTD, but the examination technique, including sonoprobe frequency, route of scanning, magnification, and landmarks of bladder wall measurement, need standardization before DWT can be widely applied for clinical diagnosis of LUTD.