Session: LBA01: Late-Breaking Abstracts I - Benign
LBA01-20: Detrusor ultrastructural study predicts long term voiding outcomes in male patients with detrusor underactivity who underwent transurethral resection of prostate (TURP)
Introduction: Patients with detrusor underactivity (DU) have a variable voiding outcome after TURP which may not be predicted by urodynamics. Our previous detrusor ultrastructural studies demonstrated that features of ‘myohypertrophy pattern’ were associated with bladder outlet obstruction(BOO) and poor short term voiding outcomes. We report the largest ultrastructural study on DU and correlate detrusor ultrastructure features with long term voiding outcomes in men with urodynamic proven DU who have had TURP. Methods: Patients with urodynamic diagnosis of DU or BOO who underwent TURP were studied. Detrusor biopsies were obtained at cystoscopy and processed for electron microscopy. Detrusor ultrastructural features including myohypertrophy pattern (cell size, irregularity), degeneration and elastosis were assessed using a simplified protocol with observers blinded to clinical data. Postoperative voiding outcomes (mean 16yrs) were correlated with ultrastructural features and urodynamic parameters. Results: 27 patients (mean age 78 yrs) were recruited (23 DU and 4 BOO). In DU patients, the mean postvoid residual urine (PVR) was 630ml (IQR 240-985). Postoperatively all BOO patients voided, 9 DU patients (39%) were catheter-free at 3 months, 14 patients (61%) required catheterisation. At long term follow-up, only 29% DU (6/21) patients were catheter-free. Functional parameters including PVR, Voiding efficiency and Bladder contractility index did not correlate with voiding outcomes. Ultrastructural studies of DU patients showed voiding outcome after TURP was significantly associated with myocyte irregularity/derangement (p=0.034) and collagenosis (p=0.041). Overall, moderate to severe changes of ‘myohypertrophy’ pattern (myocyte size variation, increased cell separation, increased intercellular collagen, degeneration) predicted poor long term voiding outcomes (p=0.029, OR of catheter-dependence 5.5). Conclusions: Detrusor ultrastructural features of myocyte irregularity, degeneration, collagenosis (moderate to severe ‘myohypertrophy pattern’) are associated with impaired detrusor contractility and predicted poor long term voiding outcomes and catheter dependence after TURP. Detrusor biopsy with ultrastructural analysis can be a useful diagnostic and prognostic tool in men with DU considering surgery. SOURCE OF Funding: Royal Australasian College of Surgeons Foundation Scholarship
