An implant to empty the bladder or close the urethra.

An implant has been designed which, in the baboon, will empty the bladder almost completely, or close the urethra so that urine does not leak out despite a contraction of the detrusor muscle. Electrodes on the 1st and 2nd sacral anterior nerve roots (corresponding roughly to the 3rd and 4th sacral in man) suffice for both actions. Closing the urethra or emptying the bladder artificially in this way seems to cause conscious, neurologically intact, baboons no discomfort. Implants have remained in place for over two years, and have emptied the bladder artificially 12 times a day for many weeks, without deterioration of function.