Validation of a non-invasive radioisotope method of imaging ureteric urine transport.
Measurement of ureteric function has hitherto involved the use of invasive techniques. A non-invasive, radioisotope method of imaging and displaying individual ureteric boluses has been described, a refinement of which is used in this department. Each "spindle" displayed using this technique theoretically represents an individual ureteric bolus of urine, but the technique has never been validated in the normal ureter in either the experimental model or man. A porcine model was set up to allow simultaneous measurement of ureteric bolus transmission using the radioisotope (compressed image) method and by the accepted techniques of electromyography (EMG) and urine drop counting. The timing of each urinary bolus, as recorded by the different modalities was then compared. The results from 11 studies showed a significant correlation between the radioisotope and EMG methods (mean r = 1.00, P = 0.0003). There was a constant relationship between the part of the radioisotopic image representing the rear end of the bolus and the EMG complex (mean time difference = 5.32 +/- 1.067s), thus defining that part of the image representing the peristaltic contraction wave. There was a variable relationship between the EMG and the part of the image representing the leading edge of the bolus (mean time difference = 13.36 +/- 5.23s), emphasising that bolus length is variable, being dependent on bolus volume. The radioisotope "spindle" concurs with EMG activity in the porcine ureter. The compressed image technique is thus validated as a non-invasive method of demonstrating ureteric urine transport.
Wemyss-Holden
G D
GD
Department of Urology, Royal Infirmary, Manchester.
Hosker
G L
GL
Rose
M R
MR
Payne
S R
SR
Testa
H J
HJ
D000818:Animals; D004576:Electromyography; D005260:Female; D011866:Radioisotope Renography; D013552:Swine; D013997:Time Factors; D014513:Ureter / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014563:Urodynamics