Tc-HMPAO rat brain scan role in the diagnosis of early diabetes: a preliminary study. First and Corresponding Author:

Background: 99m Tc-HMPAO brain scan is well-known nuclear medicine test for the detection of regional brain blood flow. As we know that diabetes can affect the blood flow in certain organs such as heart, kidneys and eyes. Brain also can be affected. Therefore, our objective of this study was to investigate the role of 99m Tc-HMPAO brain scan in detecting the early vascular changes in brain in early diabetes. Methods: There were two groups of male Wistar rats (one control and one streptozotocin (STZ) induced diabetic group). Each group contained 6 rats. Rat brain imaging using gamma camera was performed for each group after 0.5 (control), 2, 4, and 24 h post 129.5 MBq injection of 99m Tc-HMPAO. Data processing for brain scan was done by drawing a region of interest (ROI) circulating the brain (B) and a ROI around the soft tissues around the neck of each rat as background (BKG). Brain 99m Tc-HMPAO uptake minus background (net brain counts; NBC) in control rats were studied first and expressed as the mean ± standard deviation (mean±SD). Then NBC in diabetic-STZ rats were studied. Results: The NBC in control group (mean±SD) was: 67766.83±10405.19, 49439.67±6960.06, 37080.83±5459.16, 2017.00±302.72 counts per sec (cps) at 0.5, 2, 4 and 24 h respectively. The NBC in STZ group was: 241296.83±3548.81, 148215.17±2316.45, 111254.17±1682.65, 6817.83±76.36 cps at 0.5, 2, 4 and 24 h respectively. A statistical comparison (Student's t-test) between the NBC controls and the