Neurogenic bladder: a guide to evaluation and management.

The function of voiding, whether normal or abnormal, can be symbolized by a universal formula which is based on the variables of expulsion and retention of urine, timing of urine flow, and emptying of the bladder. A guide for evaluation and management of the neurogenic bladder is derived from the formula by considering the component parts of the variables separately. A minimally invasive method of evaluation and an orderly method of conservative management are described which are based upon the guide. Early application of these principles can reestablish more normal parameters of the variables and thus avoid complications.