TY - JOUR T1 - Assessment of Rapid Changes in Renal Blood Flow with <sup>191m</sup>Ir, an Ultra-Short-Lived Radionuclide JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 508 LP - 511 VL - 45 IS - 3 AU - S. Ted Treves AU - Alan B. Packard AU - Leo C.T. Fung Y1 - 2004/03/01 UR - http://jnm.snmjournals.org/content/45/3/508.abstract N2 - We investigated the feasibility of using 191mIr (half-life, 5 s) to measure rapid dynamic alterations in differential renal blood flow. Methods: A nonobstructive constant renal pelvic pressure model was used. The renal pelves of 6 New Zealand White rabbits were drained by use of bilateral catheters, and increased hydrostatic pressure was achieved by raising 1 catheter to 16, 25, 30, or 35 cm above the level of the renal pelvis. The contralateral kidney served as the control. 191mIr first-pass angiograms were obtained at baseline, after the induction of elevated pressure in the renal pelvis, and after the pressure was returned to normal. A minimum of 3 sequential angiograms were obtained at each point. Results: The differential blood flow values (mean ± SD) were 47.5% ± 7.3% at baseline, decreased to 42.3% ± 2.6% when the renal pelvic pressure was elevated (P = 0.001), and returned to 51.1% ± 4.0% after the pressure was returned to normal (P = 0.0017). There was no significant difference between baseline and postcompression values (P = 0.4807). Conclusion: It is possible to use 191mIr first-pass angiography to evaluate rapid dynamic changes in differential renal blood flow in an experimental animal model. ER -