Transabdominal Ultrasound Measurement of Detrusor Wall Thickness in Patients with Overactive Bladder

Abstract

Objective To measure the detrusor wall thickness (DWT) in patients with overactive bladder (OAB) to determine whether it can be used as a biomarker for assessment in these patients. Materials and Methods Transabdominal sonography of the bladder using an 8-MHz probe to measure DWT was performed in patients with OAB dry, OAB wet and healthy controls. Bladder volume was determined by the summation of the voided volume and the postvoid residual. The DWT for a bladder volume less than 250 mL was further corrected to an equivalent volume of 250 mL and then compared among subgroups of men and women Results A total of 208 subjects were recruited, including 69 controls, 89 patients with OAB dry and 50 patients with OAB wet. There were 101 men and 107 women. Wide variations in the DWT were noted among the subgroups. After correction for bladder volume, DWT in the OAB dry and OAB wet groups was significantly higher in men (1.41 ± 0.30 mm and 1.50 ± 0.48 mm, respectively; p< 0.0001) but not in women (1.21 ± 0.36 mm and 1.32 ± 0.39 mm, respectively; p > 0.05) when compared to controls (men, 1.02 ± 0.24 mm; women, 1.11 ± 0.32 mm). Men with OAB dry had a significantly higher corrected DWT than women, but the corrected DWT showed no significant difference between men and women with OAB wet Conclusion DWT values in patients with OAB were increased in men but not in women, suggesting a difference in the underlying pathophysiology in men with OAB. Based on our results, we do not recommend using DWT as a biomarker for assessing OAB in women.