^(18)F-FDG PET/CT和^(99m)Tc-MIBI G-MPI双核素显像评估急性心肌梗死术后心功能、心肌活力变化研究

目的通过;F-脱氧葡萄糖(FDG)PET/CT和^(99m)Tc-MIBI G-MPI双核素显像评估急性心肌梗死术后6个月心功能、心肌活力的变化。方法入组行急诊介入治疗的急性ST段抬高型心肌梗死患者11例,出院前2天及术后6个月均行;Tc-MIBI G-MPI、^(18)F-FDG PET-CT检查。比较6个月和基线的左心室舒张末期容积(EDV)、收缩末期容积(ESV)、射血分数(LVEF)、每搏量(SV)、心肌节段灌注放射性分级、心肌节段代谢放射性分级、不同心肌活力状态的数量。结果介入术后6个月由^(18)F-FDG PET-CT所得EDV、ESV、EF、SV与基线比较,差异均无统计学意义(t分别=-1.13、-1.36、0.78、-0.72,P均>0.05),由99 mTc-MIBI G-MPI所得EDV、ESV、EF、SV与基线比较,差异均无统计学意义(t分别=0.23、-0.69、0.74、0.31,P均>0.05);术后6个月心肌灌注分级低于基线(Z=2.65,P<0.05);术后6个月心肌代谢分级低于基线(Z=5.81,P<0.05);相比基线,术后6个月正常心肌节段数及完全存活心肌节段数明显增加,部分存活心肌节段数明显减少,心肌活力较基线明显改善(Z=3.81,P<0.05)。结论急性心肌梗死介入术后6个月左心功能无明显改变,心肌节段代谢分级及灌注分级改善,存活心肌节段数明显增加,心肌活力逐步恢复。

PET/CT评估犬顿抑心肌及冠脉移植骨髓干细胞对受损心肌的修复能力

目的：应用PET／CT心肌灌注／代谢显像评估顿抑心肌及冠脉移植骨髓干细胞对受损心肌的修复能力。方珐：选取杂种犬20只，手术组15只，假手术组5只。手术组动物经手术间断阻断冠状动脉左前降支（LAD）下1／3循环30、60和90rain，区分为A，B，C组，应用心电图、血生化检查、心肌灌注显像（MPI）和（或）心肌代谢显像（MMI）、组织病理、免疫组化等技术评价模型的建立并评估顿抑心肌受损的状态。假手术组不结扎冠状动脉，但观察心电图、血生化检查、MPI等指标。模型建立后将诱导分化的骨髓干细胞通过自体移植到移植组动物梗死区，通过MPI和（或）MMI、组织病理、免疫组化等技术评价干细胞移植治疗后6wk和10wk的效果。结果：1．手术中除B组1只动物死亡外，其余14只动物结扎LAD24～48h后的心电图、9～12h静脉血清心肌酶谱、2d后MPI均提示符合心肌梗死改变。假手术组的心电图和血生化指标和MPI均正常。2．模型建立后A，B及C组2～3dMPI／MMI发现心肌梗死节段数及梗死区存活心肌节段数分别为11／12（92％），8／11（73％）及5／15（33％），相应电镜检查则提示缺血区有不同程度的存活心肌。3．手术组移植后有存活心肌的细胞节段，虽然细胞移植6wk与移植后5～7d灌注／代谢无明显变化（P〉0．05），但细胞移植10wk与移植后5～7dMPI／MMI比较有明显改变（P〈0．01）；无存活心肌的细胞节段，细胞移植6wk及10wk灌注／代谢均无明显变化（P〉0．05）。假手术组细胞移植后5～7d、6wk和10wk的MPI／MMI提示心肌梗死节段的灌注及代谢变化均无明显变化。结论：PET／CTMPI是评价急性心肌梗死模型成功的有效方法。MPI／MMI可以确定不同缺血状态的部位，范围及程度，而且可以用于评估顿抑心肌。并可以反映细胞移植后的细胞代谢情况。

Clinical Utility of N-13 Ammonia Cardiac PET Perfusion Imaging in the Assessment of Epicardial Coronary Lesions of Intermediate Range

Objective: To identify the high risk myocardial perfusion defects which prognosticate the future ischemic cardiac events, on Positron emission tomography (PET) myocardial perfusion imaging (MPI) of intermediate coronary stenosis (ICS) on coronary angiogram (CAG) with negative single photon emission computed tomography (SPECT) MPI in chronic stable angina (CSA) patients. Methods: For this study non-infarcted CSA patients of single vessel disease (SVD) on CAG with ICS and normal LV function were selected. In all patients with negative stress SPECT MPI, stress PET MPI was done. In both scans, extent score (ES), severity score (SS), total severity/extent score ratio (TS-ES R) and Left ventricular dilatation (LVD) were noted. Patients with Positive PET MPI were closely followed for 2yrs and PCI was performed depending on symptoms. Results: Out of 47 study group patients, during 2yr follow up period, 11 out of 15 patients with ischemia positive PET MPI underwent percutaneous coronary intervention (PCI). Indication for PCI was rest or persistence or recurrence of angina. Four of 15 patients remained asymptomatic. In medically managed vs. PCI done patients, mean of ES was 1.2 ± 0.5 vs. 2.3 ± 1, SS was 1.2 ± 0.5 vs. 5.3 ± 1.9, TS-ESR was 1 vs. 2.5 ± 0.5 which was statistically significant (p = 0.01). Conclusion: It was inferred that subgroup of PET MPI positive ICS patients with basal PET MPI showing SS > 5 and TS-ES R > 1.5 with LVD during stress required close follow up as they are likely require PCI subsequently. Condensed Abstract: As negative for inducible ischemia by single photon emission computed tomography myocardial perfusion imaging (SPECT MPI) is associated with low cardiac event rate, even though positive imaging by Positron emission tomography myocardial perfusion imaging (PET MPI), in patients with intermediate Coronary stenosis (ICS) may not require immediate percutaneous coronary intervention (PCI). We fol-lowed these patients for two 2yrs and identified that basal PET MPI showing total severity score > 5 and total severity/ extent score ratio > 1.5 with Left ventricular dilatation during stress required PCI subsequently.

正电子发射成像影像中动态纠正方法的研究

正电子发射成像(PET)在脑部医学诊断成像过程中被测者的头部移动容易产生图像模糊、伪影等现象,大大降低了图像质量。单纯的使用头部固定系统来防止病人的头部移动难以取得良好的效果。因此必须通过软件的后期处理,达到纠正成像动态错误的目的。笔者提出的动态错误纠正方法通过研究MPI-Tool、SPM和PMOD软件的配合使用,使得头部动态错误得到有效纠正,减少伪影,提高了图像质量,对于提高诊断的有效性和科学性具有重要意义。