Cystometric Bladder Pressure Determinations: Their Clinical Importance

Abstract

The cystometer is an instrument devised to record graphically the bladder wall resistance in mm. of Hg as the bladder is gradually filled, its contents being simultaneously recorded in cc. of fluid. The neuro-anatomical changes and physiological principles for interpretation of results consist primarily in the facts that (1) the sympathetics from the 2nd dorsal to the 3rd lumbar are considered as nerves of bladder filling; (2) the parasympathetics from the 2nd and 3rd sacral, as nerves of bladder emptying; (3) the pudic nerve of sacral origin, as innervating the muscles whose partial action is to depress the internal sphincter upon voiding. Destruction or irritation of the sympathetics, parasympathetics or low spinal nerves may be easily interpreted from cystometric curves and furnish valuable data in diagnosing spinal cord lesions. This, in turn, is valuable in diagnosing central nervous system syphilis, in determining prognosis in bladder neck obstruction with consequent bladder wall compensation or decompensation, and in evaluation of fixation of bladder wall diverticula.