DIURETIC RENAL SCINTIGRAPHY IN NORMAL DOGS

Diuretic renal scintigraphy is commonly used in human medicine to differentiate obstructive from nonobstructive pyelectasia. In order to determine normal parameters,99mTc‐DTPA renal scintigraphy was performed twice in 20 healthy adult Mongrel dogs. Each dog was injected with either 3.0 mg/kg furosemide or an equivalent volume of saline 4.5 min following injection of the radiopharmaceutical. The following parameters were evaluated: (1) global and individual glomerular filtration rate (GFR); (2) time of peak (TOP) of the time–activity curve (TAC); (3) shape of the TAC; (4) individual kidney excretion half‐time (T1/2); (5) proportion of maximum activity measured at end of study (8 min); (6) time of onset; and (7) duration of the effect of the diuretic. Most TAC in the diuretic renography group showed a steep drop in the curve following administration of the diuretic compared with a gradual slope in the saline control group. There was a statistically significant difference inT1/2between the control renograms (median 10.25 min, range 4.41–18.07 min) and the diuretic renograms (median 4.16 min, range 3.62–5.90 min). There was a statistically significant difference in percentage maximum activity between the control renograms (median 65.25%, range 48.27–93.68%) and the diuretic renograms (median 48.54%, range 35.64–58.76%). Median time of onset of the diuretic effect was 1.10 min (0.20–2.40 min), and median duration was 0.83 min (0.30–2.35 min).