Matsunari I, Böning G, Ziegler S I, Nekolla S G, Stollfuss J C, Kosa I, Ficaro E P, Schwaiger M
Nuklearmedizinische Klinik und Poliklinik der Technischen Universität München, Klinikum rechts der Isar, Munich, Germany.
J Am Coll Cardiol. 1998 Oct;32(4):927-35. doi: 10.1016/s0735-1097(98)00340-4.
The purpose of this study was to assess the efficacy of attenuation-corrected (AC) technetium-99m (99mTc)-tetrofosmin single-photon emission computed tomography (SPECT) in detecting viable myocardium compared to 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET).
The role of 99mTc-labeled perfusion tracers in the assessment of myocardial viability remains controversial. Attenuation artifacts affect the diagnostic accuracy of SPECT images.
Twenty-four patients with coronary artery disease (mean left ventricular ejection fraction 30%) underwent resting 99mTc-tetrofosmin SPECT and FDG PET imaging. Both AC and non-attenuation-corrected (NC) SPECT images were generated.
Using a 50% threshold for viability by FDG PET, the percentage of concordant segments of viability between 99mTc-tetrofosmin and FDG on the patient basis increased from 79.8%+/-14.0% (mean+/-SD) on the NC images to 90.8%+/-10.6% on the AC images (p=0.002). The percentage of 99mTc-tetrofosmin defect segments within PET-viable segments, an estimate for the degree of underestimation of viability, decreased from 19.8%+/-15.2% on the NC images to 9.7%+/-12.6% on the AC images (p=0.01). Similar results were obtained when a 60% threshold was used to define viability by FDG PET. When the anterior-lateral and inferior-septal regions were separately analyzed, the effect of attenuation correction was significant only in the inferior-septal region.
The results indicate that AC 99mTc-tetrofosmin SPECT improves the detection of viable myocardium mainly by decreasing the underestimation of viability particularly in the inferior-septal region, although some underestimation/overestimation of viability may still occur even with attenuation correction.
本研究旨在评估衰减校正（AC）的锝-99m（99mTc）-替曲膦单光子发射计算机断层扫描（SPECT）与18F-氟脱氧葡萄糖（FDG）正电子发射断层扫描（PET）相比在检测存活心肌方面的疗效。
99mTc标记的灌注示踪剂在评估心肌存活中的作用仍存在争议。衰减伪影会影响SPECT图像的诊断准确性。
24例冠心病患者（平均左心室射血分数30%）接受静息99mTc-替曲膦SPECT和FDG PET成像。生成了AC和非衰减校正（NC）的SPECT图像。
以FDG PET的50%存活阈值为标准，基于患者的99mTc-替曲膦与FDG之间存活节段的一致百分比从NC图像上的79.8%±14.0%（均值±标准差）增加到AC图像上的90.8%±10.6%（p = 0.002）。PET存活节段内99mTc-替曲膦缺损节段的百分比（对存活低估程度的估计）从NC图像上的19.8%±15.2%降至AC图像上的9.7%±12.6%（p = 0.01）。当以60%阈值定义FDG PET的存活时，获得了相似结果。当分别分析前外侧和下间隔区域时，衰减校正的效果仅在下间隔区域显著。
结果表明，AC 99mTc-替曲膦SPECT主要通过减少对存活的低估来改善存活心肌的检测，尤其是在下间隔区域，尽管即使进行了衰减校正仍可能发生一些对存活的低估/高估。
