High percentage of neurologic deficits in the electrophysiology study of the lower urinary tract in patients with detrusor underactivity and chronic urinary retention

Abstract

Objectives: Both detrusor underactivity (DU) and bladder outlet obstruction are the common causes of chronic urinary retention. Some novel treatment approaches focus on modulating micturition reflex and external urethral sphincter (EUS) function. This study used electrophysiologic (EP) studies to investigate the micturition reflex and EUS conditions of chronic urinary retention patients. Methods: Sixty patients with urodynamic DU and chronic urinary retention were studied using (1) bulbocavernous reflex (BCR) by electric stimulation, (2) electromyography (EMG) of the EUS, and (3) nerve conduction velocity (NCV) studies of the pudendal nerve. The EP findings were analyzed in DU patients with different etiologies. Results: The BCR was positive in 41.7% of patients. In EMG studies, denervation, reinnervation, and reduced recruitment of the EUS were observed in 21.7%, 71.7%, and 88.3% patients, respectively. Decreased amplitude of pudendal nerve conduction in NCV studies was noted in 73.3% of patients. Patients with sacral neuropathy had a lower BCR positive rate (p = 0.001), a nonsignificant but higher denervation rate (p = 0.059) in EMG studies, and a higher rate of decreased amplitude in NCV (p = 0.011) than those without sacral neuropathy. Excluding patients with sacral neuropathy or diabetes mellitus, a high percentage of neurologic deficits was still detected in EP studies. Conclusions: Chronic urinary retention patients with urodynamic DU not only have bladder dysfunction, but also potential neuropathy in the sacral reflexes, pudendal nerve, or urethral sphincter innervation. The neurologic deficits explored in EP studies may affect the decision-making around the therapy to restore the voiding function in DU.

Therapeutic outcome of active management in male patients with detrusor underactivity based on clinical diagnosis and videourodynamic classification

“…Some patients with clinical DU might be due to absent or diminished bladder sensation, resulting in inability to initiation or early termination of the completeness of voiding process 12 . From the electromyographic study of patients with DU and chronic urinary retention, we found the causes of DU included bladder dysfunction, neuropathy in sacral reflexes, pudendal nerve, and urethral sphincter innervation 24 . Bladder sensation was decreased and CBC was larger in the DU group than in the detrusor hyperactivity and inadequate contractility, hypersensitive bladder, and DO groups.…”

Detrusor Underactivity in Men with Bladder Outlet Obstruction

“…The study also included patients with closed bladder neck while voiding. If the impact from BOO results in afferent or efferent neuropathy, surgery may be not satisfactory [ 30 ].…”