[Assessment of left ventricular wall thickening with gated 99mTc-MIBI SPECT--value of normal file]

The wall thickening was assessed by regional count increase from end-diastole (ED) to end-systole (ES) in gated 99mTc-MIBI SPECT. The wall thickening index was calculated as (ES count--ED count)/ED count x 100 (% thickening). Gated SPECT was performed three hours after injection of 600 MBq of 99mTc-MIBI in 20 normal subjects to create normal files (ED, ES perfusion maps and % thickening map). In normal ED and ES perfusion maps, distribution in anterior and lateral regions were higher than other regions, indicating heterogeneous perfusion. In addition, the % thickening in apex was higher than anterior and lateral and septal regions, suggesting heterogeneous % thickening in normal subjects. Furthermore, the % thickening was different between male and female. We conclude that quantitative analysis of regional thickening can be performed by gated 99mTc-MIBI SPECT with normal files.