Roelants Véronique, Bernard Xavier, Walrand Stephan, Bol Anne, Coppens Ann, Jamart Jacques, Melin Jacques, Vanoverschelde Jean-Louis
Department of Nuclear Medicine, Cliniques Universitaires St-Luc, Université Catholique de Louvain, Brussels, Belgium.
Nucl Med Commun. 2006 Oct;27(10):815-21. doi: 10.1097/01.mnm.0000237985.23973.fb.
We determined the value of attenuation correction (AC) of myocardial perfusion estimation with (99m)Tc-MIBI SPECT in overweight patients by comparison of uncorrected (filtered back-projection (FBP) and corrected (an iterative algorithm with a measured attenuation coefficients map (FL-AC)) (99m)Tc-MIBI relative uptake to perfusion data obtained in the same patients with NH3 PET. In addition, the impact of attenuation correction for the assessment of myocardial viability with (99m)Tc-MIBI SPECT was determined using FDG PET as the reference method.
Thirty consecutive overweight patients (BMI=28+/-4) with left ventricular dysfunction underwent a resting (99m)Tc-MIBI SPECT and a PET study (NH3 and FDG). (99m)Tc-MIBI SPECT scans were reconstructed without attenuation correction (FBP) and with attenuation correction (FL-AC). The left ventricle was divided into 16 segments, in which the relative uptake was quantified using circumferential profiles. A relative uptake > or = 60% was considered consistent with viable myocardium for FDG and MIBI.
The absolute difference between (99m)Tc-MIBI SPECT and NH3 PET uptakes was less pronounced in the inferior (12+/-10% vs. 17+/-12%, P<0.001), anteroseptal (12+/-11% vs. 16+/-12%, P=0.009) and septal (15+/-12% vs. 18+/-14%, P=0.003) regions (FL-AC vs. FBP, respectively). The sensitivity of MIBI for diagnosing myocardial viability increased from 83 to 100% (P=0.034), without loss in specificity.
Attenuation correction improves myocardial perfusion estimation by (99m)Tc-MIBI SPECT in the inferior, anteroseptal and septal regions and increases its sensitivity for the diagnosis of myocardial viability.
通过比较未校正（滤波反投影法（FBP））和校正（使用测量衰减系数图的迭代算法（FL-AC））的（99m）锝-甲氧基异丁基异腈单光子发射计算机断层扫描（SPECT）中（99m）锝-甲氧基异丁基异腈的相对摄取与同一患者氨（NH3）正电子发射断层扫描（PET）获得的灌注数据，我们确定了在超重患者中（99m）锝-甲氧基异丁基异腈SPECT心肌灌注估计的衰减校正（AC）值。此外，以氟代脱氧葡萄糖（FDG）PET作为参考方法，确定了（99m）锝-甲氧基异丁基异腈SPECT评估心肌存活性时衰减校正的影响。
30例连续的左心室功能不全超重患者（体重指数（BMI）=28±4）接受静息状态下的（99m）锝-甲氧基异丁基异腈SPECT和PET检查（NH3和FDG）。（99m）锝-甲氧基异丁基异腈SPECT扫描分别采用无衰减校正（FBP）和有衰减校正（FL-AC）进行重建。左心室分为16个节段，使用圆周轮廓对其中的相对摄取进行定量分析。对于FDG和甲氧基异丁基异腈，相对摄取≥60%被认为与存活心肌一致。
在FL-AC与FBP相比时，下壁（12±10%对17±12%，P<0.001）、前间隔（12±11%对16±12%，P=0.009）和间隔（15±12%对18±14%，P=0.003）区域中，（99m）锝-甲氧基异丁基异腈SPECT与NH3 PET摄取之间的绝对差异较小。甲氧基异丁基异腈诊断心肌存活性的敏感性从83%提高到100%（P=0.034），特异性未降低。
衰减校正可改善（99m）锝-甲氧基异丁基异腈SPECT在下壁、前间隔和间隔区域的心肌灌注估计，并提高其诊断心肌存活性的敏感性。
