1978 Volume 69 Issue 8 Pages 959-967
The measurement of urethral pressure profile can be carried out under simultaneous fluoroscopic visualization of posterior urethral changes by means of X-ray television.
This investigation was initially performed on 4 adult males having normal micturition under two different conditions: the measurement of UPP was done before the cystometrogram (in empty bladder) and after the cystometrogram (in full bladder which gives a more than minimal desire for urination).
The profile curves with full bladder showed no marked increase in pressure along the functional urethral length (FUL) when compared to those with empty bladder. The FUL was however shortened.
The tendency to shorten the FUL of the full bladder was more remarkable at the distal portion of posterior urethra than at the proximal portion.
It is believed that the FUL is shortened when the thickness of the bladder wall at the cervical portion diminishes and stretches laterally as the bladder is distended (descending tendency).
A group of pelvic striated muscles, on the other hand, increases their tension following distention of the bladder.
These conditions will make the posterior urethra positioned higher and, consequently, the ascending tendency of the distal portion of posterior urethra becomes greater than that of the descending proximal end.
In clinical applications, 12 patients with spinal cord injury were studied during the spinal shock or initial recovery stage using the same method. Some patients, in spite of their atonic paralysis shown in the cystometrogram, exhibited a remarkable rise in urethral pressure when the bladder was full. In such cases, the fluoroscopic visualization revealed that the FUL was not shortened and the bladder neck remained in a closed state. A few patients, on the cotrary, exhibited a rise in pressure with the bladder neck opened while the bladder was distened.
It is therefore indicated that conditions of the bladder neck should be confirmed as to whether it is closed or open before having the patient with a UPP rise go through TUR incision. Moreover, the UPP measurement using X-ray television is useful to determine whether certain drugs such as adrenolytic agents have exerted effects on the bladder neck.
Finally, it is to be noted that X-ray irradiation time during the course of the UPP curve should be as short as possible from the safety point of view and the catheter drawing should also be done as speedily as possible within a limitation.
