The variability of normal male voiding patterns measured by drop spectrometry.

Voidings from 7 healthy men were recorded by means of the urinary drop spectrometer. The voiding patterns were characterised by the trend drop frequency and the distribution of drop time intervals. The variability of these voiding patterns was studied by statistical techniques. The data were grouped for each person. Variances were considerable both within and between groups. Although individual differences in the mean values existed, the groups could not be separated from each other.

Preoperative evaluation of patients with bladder outlet obstruction with particular regard to excretory urography.

During the last 15 years excretory urography has been a routine preoperative diagnostic procedure for patients with bladder outlet obstruction in our department and, perhaps, for many more years in other urological centers. There are 2 reasons that this investigation should be done: 1) to detect abnormalities of the upper urinary tract that can be important indicators to operate or for the postoperative course and 2) to detect abnormalities in the bladder that should be corrected simultaneously with the prostatectomy or that can interfere with the procedure.

The physical basis of some urodynamic measurements.

This report concerns certain principles of physics that are relevant to the clinical practice of Urology as well as the research urodynamicist. Supplemental material is available in previous publications for the physiologist, cardiovascular, dynamicist, anesthesiologist and the like. The material is fairly recent only in its application to the lower urinary tract. Pressure-volume relationships were applied to be cardiovascular system more than 20 years age. Indeed, for those interested in urodynamic methods, there is a vast fund of useful pertinent information in the literature on vascular dynamics. The problems of steady and unsteady flow in flexible structures are common to both specialties. It would be unfortunate if urodynamicists were required to learn of the phenomena and their implications by the drudgery of repeated measurements rather than taking guidance from previous work. This report is intended to serve as an introduction to the approach and, hopefully, will stimulate those who are interested in urodynamic methods to seek out this information and to interpret their measurements in the light of fundamental physical phenomena that have been described and analyzed.

A new aspect of voiding dynamics: the relationship between flow rate and the frequency of drops in the external urinary stream.

The method of drop spectrometry gives the possibility of registering the instantaneous trend drop frequency and the instantaneous trend flow rate. By plotting the flow rate against the frequency, patterns are obtained which depend on the flow and the elasticity of the external meatus.

Preoperative evaluation of patients with bladder outlet obstruction with particular regard to excretory urography.

During the last 15 years excretory urography has been a routine preoperative diagnostic procedure for patients with bladder outlet obstruction in our department and, perhaps, for many more years in other urological centers. There are 2 reasons that this investigation should be done: 1) to detect abnormalities of the upper urinary tract that can be important indicators to operate or for the postoperative course and 2) to detect abnormalities in the bladder that should be corrected simultaneously with the prostatectomy or that can interfere with the procedure.

A clinical and urodynamic study of tadenan in the treatment of benign prostatic hypertrophy.

20 patients with benign prostatic hypertrophy were admitted to a double-blind noncrossover study for evaluation of the effect of Tadenan. Using either standard clinical criteria or urodynamic data obtained by the urinary drop spectrometer, no significant effect was found for the dosage and period of administration used.

Action of beta-adrenergic blocking agents on the urethral pressure profile.

The action of beta-adrenergic blocking agents on the urethral pressure profile was studied. Sotalol, 20 mg, and inderal, 7 mg, were administered intravenously. Whereas the alpha-adrenergic blocking drug phentolamine, as already known, changed the maximum value of the pressure profile with an average decrease of 33%, the beta-adrenergic blocking drugs did not show any action at all. There was no difference between the results obtained with Sotalol and Inderal.

Megestrol acetate in treatment of benign prostatic hypertrophy.

In this study we found no significant effect on benign prostatic hypertrophy due to megestrol using standard clinical criteria. However, there is evidence using urinary drop spectrometer data which makes one suspect that megestrol does have a positive effect. If there is an effect, it is apparently so small as to be undetectable using the clinical protocol of this investigation. Since the urodynamic evidence does indicate a possibility of a positive effect, it appears reasonable to investigate further using a different protocol - perhaps a higher dosage and/or a more controlled test population.