Neurourologic evaluation after resection of the sacrum

Five patients with bilateral, and four patients with unilateral, well defined sacral nerve lesions after sacral resection for tumor were examined with a clinical evaluation, cystometry, and cystoscopy including a test of vesical and urethal sensibility with different stimuli. In patients with bilateral division of the sacral nerves below the S 2 level, no active detrusor contractions were registered, indicating that the second sacral segment alone cannot subserve the micturition reflex. In patients with unilateral division of sacral nerves 1 to 5 or 2 to 5, a normal micturition reflex was registered. There was a complete loss of bladder mucosal pain when sacral nerves 3 to 5 had been cut bilaterally, while the sensibility was normal when sacral nerves 4 to 5 had been cut bilaterally. In patients with unilateral division of all sacral nerves below L 5 or S 1, mucosal pain tested by means of electrcoagulation of the bladder and pin-pricking of the urethra could not be felt on the denervated side. Stretching of the detrusor wall with a ureteral catheter, however, could be felt on the denervated side, indicating that this sensation was not mediated in sacral nerves but probably in the hypogastric nerves. Thermesthesia of the mucosa was demonstrated on the intact side of the bladder but not on the denervated side when the patients with unilateral sacral nerve lesions were tested with jet streams of cold or hot saline against the bladder wall.