Neurophysiologic study in idiopathic overactive bladder

Abstract

Aim: Idiopathic overactive bladder (OAB) is a prevalent, mystifying disorder with a questionable neurogenic background. We aimed to investigate the possible subtle neuropathic affection underlying its pathogenesis.

Methods: A cross-sectional cut off study was carried out on a series of 38 females with idiopathic OAB and 22 healthy matched female volunteers. The following was performed: symptom score questionnaire, determination of pudendal nerve terminal motor latency (PNTML), sacral reflexes' latencies, pudendal somatosensory evoked potentials, and needle electromyography of the external anal and urethral sphincters.

Results: A highly significant prolongation of PNTMLs and sacral reflexes latencies among the patients group was detected (P ≥ 0.001). Pudendal somatosensory evoked potentials showed non- significance among the two studied groups (P ≥ 0.05). External anal sphincter neuropathic affection was detected in 27 patients (71%) and external urethral sphincter neuropathic affection was detected in 30 patients (78.9%). The clitoral anal reflex showed the highest sensitivity and specificity among the neurophysiologic tests used in assessing the neuropathic affection (86.7 and 83%, respectively), followed by PNTML (83.3 and 80%, respectively).

Conclusion: Pudendal neuropathy is the dominating possible attributing factor in the pathogenesis underlying idiopathic OAB. An integrated clinical, urodynamic, and electro-physiological assessment is recommended for evaluation of any overactive bladder patients.

Keywords: detrusor overactivity; pelvic floor electromyography; pudendal nerve terminal motor latency; sacral reflexes.