201Tl与13N-NH3、18F-FDG PET心肌显像判断存活心肌的对比研究

目的　比较再注射2 0 1T1心肌显像与联合应用13 N NH3 及18F 脱氧葡萄糖 (FDG)心肌PET显像判断存活心肌的临床价值。方法　 2 0例心肌梗死患者 ,行2 0 1T1SPECT负荷、再分布、再注射显像及13 N NH3 、18F FDGPET心肌显像。将左室分成 9个节段 ,以视觉评价法对放射性分布进行 4级评分。获得2 0 1T1SPECT再分布、再注射像及18F FDGPET显像的局部心肌摄取率 (%ID)。结果　PET判定为存活心肌的 48个节段中 ,45个节段 (93.8% ) 2 0 1T1再注射像也判定为存活心肌。在2 0 1T1再分布像示放射性分布严重低下的 2 4个节段 ,2 0 1T1再注射像与PET显像判定存活心肌的一致率为 87.5 % ,其中 37.5 %为存活心肌节段 ,5 0 %为无存活心肌节段。 2种显像方法的 %ID无明显差异 ,且呈显著正相关 (r=0 .72 2 )。结论　再注射2 0 1T1心肌显像判断存活心肌的准确性与PET心肌显像相似 ,有较大的临床应用价值。

Comparative study of 201Tl reinjection tomography and combined use of 13N-ammonia and 18F-fluorodeoxyglucose positron emission tomography for detection of viable myocardium

Objective To compare the clinical value of 201Tl reinjection tomography and combined use of 13N-ammonia (NH 3) regional myocardial perfusion and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) for detection of viable myocardium. Methods We performed exercise 201Tl SPECT (Tl SPECT) on 20 patients with myocardial infarction and obtained standard 201Tl exercise-redistribution images. 201Tl was reinjected immediately after redistribution study, and the images were then acquired as also. The 20 patients also underwent PET imaging with 13N-NH 3 and 18F-FDG (NH 3-FDG PET) within one week of the above study. Vertical and horizontal long axis cuts were divided into nine segments, and uptakes of radioisotope were evaluated into four classes visually (Defect score, DS) (0:normal uptake, 3:severely reduced). Quantitative evaluation was performed on the vertical and horizontal long axis cuts of 201Tl redistribution, reinjection and FDG PET images using regions of interest. The relative myocardial 201Tl uptake and 18F-FDG uptake (%ID) were expressed as the percentage of this reference region accounted for of the maximal counts. Results In 48 segments identified as viable by the NH 3-FDG PET images, 45 (93.8%) segments were also identified as viable by the 201Tl redistribution imaging. Of 24 segments with severe irreversible defects on the 201Tl redistribution imaging,87.5% of the segments were concordantly confirmed by 201Tl reinjection and NH 3-FDG PET images with 37.5% identified as viable and 50% identified as scar. There was no significant difference in the average %ID, furthermore, regression analysis revealed a high positive correlation in the segmental %ID between 201Tl reinjection and FDG PET images in the 61 segments with myocardial infarction (r=0.722). Conclusions The results show that 201Tl reinjection tomography is of similar accuracy with NH 3-FDG PET for detection of viable myocardium and possesse important clinical practice value.