Urodynamic Events: Summary
A summary of the events which take place during the peristaltic contractions is shown in this recording. The effect of the peristalsis involves all of the papillary structures. The upper recording illustrates three phases of contraction and relaxation: T1, T2 and T3. It corresponds to the delineated area in the lower recording.
T1 is the peristaltic contraction which lasts 0.5 seconds. A urine bolus moves through the collecting ducts with a velocity of 1.6 mm/second. Fluid is reabsorbed from the collecting duct lumen. Flow in the capillaries and the loops of Henle ceases and these structures are emptied.
T2 is the first 0.5 seconds of relaxation. There is still no flow in the collecting ducts but flow in the vasa recta and loops of Henle resumes. The fluid reabsorbed from the collecting ducts presumably moves into the blood vessels and the ascending loops of Henle.
The two seconds of T3 is the later period of relaxation. Flow in the collecting ducts resumes in this period. Flow in the capillaries and loops of Henle is again continuous.
Tracings of Pelvic Contractions