Bladder neck incompetence in patients with spinal cord injury: Significance of sympathetic skin response

Purpose: We investigated whether recording the perineal sympathetic skin re sponse, which reflects the sympathetic function of the thoracolumbar spinal cord, represents a reliable and accurate diagnostic tool for assessing bla dder neck competence and incompetence. Materials and Methods: We compared the sympathetic skin response recorded f rom the hand, foot and perineal skin with urodynamic findings in 90 patient s with neurogenic bladder dysfunction, including 66 with spinal cord injury and 24 with cauda equina lesions. Results: Video urodynamics revealed an incompetent bladder neck in 11 of 32 patients (34%) with complete and 7 of 34 (21%) with incomplete spinal cord injury but in only I of 24 (4%) with the conus-cauda equina syndrome. This association significantly correlated with the lesion level at T10 to L2 in 12 of 26 cases (46%) as well as with the loss of perineal but preserved ha nd and foot sympathetic skin response in 13 of 18 (72%). Conclusions: Recording the perineal sympathetic skin response in addition t o that of the hand and foot represents a sensitive diagnostic tool for asse ssing sympathetic nerve function within the thoracolumbar spinal cord. It i s of diagnostic value for evaluating neurogenic bladder neck incompetence i n spinal cord injured patients.