Micturition Studies in Infants and Children: Urodynamics in Boys with Disorders of the Lower Urinary Tract

Urodynamics were studied in one group of boys with definite infravesical obstruction and in another group with various other disorders of the lower urinary tract. They were compared with a group of normal cases and a control group without infravesical obstruction. In the group with a priori definite infravesical obstruction, opening pressure, maximum voiding pressure and peak-flow pressure relatively often fell outside the 2 standard deviations of the control group. As regards other pressure variables, there was a high degree of overlap between normal and abnormal micturition. In individual patients combinations of normal pressure/decreased flow were observed. Bladder pressure measurement alone provides only a limited basis for evaluation. Boys with lesions of the lower urinary tract use abdominal straining to a much greater extent than normal boys, but apparently with little improvement in bladder emptying. Maximum flow in all patients with a priori definite infravesical obstruction fell outside the lower normal limit. All these cases had increased minimum urethral resistance. In a number of patients with a priori doubtful infravesical obstruction normal maximum flow was combined with slightly increased intravesical pressure. Estimation of maximum flow and evaluation of the flow curve would appear to constitute a suitable method for urodynamic screening. The various micturition patterns in different diagnostic groups are exemplified. The method employed provides valuable diagnostic information.