Diminished Tc-99m HMPAO pulmonary uptake in ex-smokers.
Normally, there is no localization of Tc-99m HMPAO in the lungs. Tc-99m uptake in smokers' lungs has been reportedly higher than in nonsmokers. Thus, the lung uptake may be used as a barometer of cigarette smoking. To assess whether there is a decrease in pulmonary uptake of Tc-99m HMPAO after cessation of smoking, the authors investigated the lung uptake of 31 male ex-smokers in comparison to smokers and nonsmokers. Anterior and posterior images were taken 10 minutes after intravenous injection of 20-25 mCi of Tc-99m HMPAO. Regions-of-interest over the liver and lungs in the anterior view were calculated. Duration of abstinence from smoking ranged from 5 months to 50 years. The mean lung/liver uptake in ex-smokers was 0.489 +/- 0.019 (sem). In a previous report, the mean lung/liver ratio for smokers (N = 30) was 0.805 +/- 0.040 (sem) and 0.408 +/- 0.019 (sem) for nonsmokers (N = 25). Compared with smokers, the lung/liver uptake ratio of ex-smokers was significantly lower (P < 7 x 10(-9)). The lung/liver uptake ratio of ex-smokers was significantly higher than that of nonsmokers (P < 0.005). The authors conclude that pulmonary Tc-99m HMPAO uptake of smokers is significantly diminished after quitting smoking. However, the lung uptake of ex-smokers is higher than that of non-smokers. The uptake in the lung induced by smoking appears to be partially reversible after the cessation of smoking.
Shih
W J
WJ
VA Medical Centers, Lexington, Kentucky 40511, USA.
Lee
J K
JK
Coupal
J
J
Lai
Y L
YL
Grunwald
F
F
Biersack
H
H
D000368:Aged; D005260:Female; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D015609:Organotechnetium Compounds; D010091:Oximes; D011877:Radionuclide Imaging; D012907:Smoking / Q000009:adverse effects; D016540:Smoking Cessation; D019690:Technetium Tc 99m Exametazime; D013997:Time Factors
D015609:Organotechnetium Compounds; D010091:Oximes; D019690:Technetium Tc 99m Exametazime