In vivo Distribution of Tc-99m ECD in Patients with CNS Disease on Whole Dody Scan

Keimyung Medical Journal 1999;18(1):109-116.

중추신경계 질환에서 전신 스캔으로 본 Tc-99m ECD의 생체 내 분포

류종걸; 김순; 전석길

Abstract

We evaluated prospectively in vivo distribution of Tc一99m Ethyl cysteinate dimer (ECD) in patients with central nervous system (CNS) diseases; especially in brain; liver and lung. Whole body scans were performed in 150 patients with CNS diseases at one hour after the injection of 800 MBq Tc-99m ECD. The clinical comments were divided into six groups such as vertigo (n=64);seizure (n=30);psychiatric symptoms (n=9); post-traumatic symptoms (n=7); cerebrovascular accident (CVA; n=34) and others (n=6). Mean counts/pixel of brain (B)’ liver (H); lung (P) were calculated with same-sized region of interest (ROI)s in whole body scan; and H/B and P/B ratios were analyzed. The same kind of study with Tc一99m Hexamethylpropylene amine oxime (HMPAO) was done in twelve cases. Average H/B and P/B ratios in all patients studied with Tc一99m ECD were 0.99 土 0.35 and 0.50 ± 0.26; respectively. Average H/B and P/B ratios in male (1.11± 0.30 and 0.57 ± 0.29) were significantly higher than those in female (0.86 士 0.35 and 0.42 土 0.20) (p < 0.05). The H/B ratio was not significantly different among six different clinical comment groups; but P/ B ratio in CVA was significantly higher than those in other groups (p < 0.05). Average H/B and P/B ratios of Tc?99m ECD (0.99 士 0.35 and 0.50 土 0.26) were much lower than those of Tc-99m HMPAO (2.40 ± 0.63 and 1.09±0.34)(p < 0.05). The hepatic uptake of Tc-99m ECD was nearly same as the brain uptake; and lung uptake was lower than that of brain; similar to those in normal volunteers. Liver and lung uptakes of Tc-99m ECD in male were higher than those in female; and lung uptake in CVA was higher than those in other clinical comment groups. Tc-99m ECD was more safe than Tc-99m HMPAO in view of the radiation exposure to liver and lung.

Key Words: Tc-99m ECD, Whole body scan, in vivo Distribution, Hepatic uptake, Lung up take