Renal scintigraphy in dogs

摘要: Renal scintigraphy has been used widely to measure the individual kidney glomerular filtration rate (IKGFR). In dogs, estimated GFR is calculated by a regression equation relating percent of injected dose radiopharmaceutical, technetium-99m DTPA (dietylene-triaminepentaacetic acid), taken up kidneys known standard (plasma) clearance normalized bodyweight (BW). Uptake integral (area under curve) time activity curve (TAC) renogram, which corrected for attenuation radiation in body from surface back and background activity. A more physiologically correct method normalize plasma volume (GFR/PV), requires region interest (ROI) left ventricle (LV). The first aim thesis was determine variations within minimize them improve accuracy methods. Physiological variability among dogs on different days also studied. stable than slope recommended calculating IKGFR/BW. best methods measuring were: semi-automatic drawing ROI with 20% threshold, perirenal at one pixel wide out ROI, threshold color scale rather continuous depth calculate attenuation, interval between 30 – 120 seconds start TAC. Measurement variation caused significant observer variability, indicates that must be standardized same person should all compared results. Physiologic day-to-day normal mostly found accounted most variability. GFR/PV not affected LV sizes. Subtracting extravascular did precision, but increased due sizes intervals chosen plot. Manual without subtraction input 1 4 minutes are recommended.