国产4环/7层PET仪初试

Preliminary evaluation of 4 rings/7 slices domestic PET scanner

对我国１９９６年研制成功的４环／７层ＰＥＴ仪（轴向视野８ｃｍ）进行试用。先进行模型试验和动物实验，然后对１例正常志愿者和７例患者进行１８Ｆ脱氧葡萄糖（ＦＤＧ）ＰＥＴ显像。静脉注射１８ＦＦＤＧ３７０ＭＢｑ后约１５小时显像，成人全身显像行１１个床位采集，约１５小时，心脑局部显像行２～３个床位采集，约半小时。直径１～３ｃｍ的阴模和阳模皆可显示。８例全身冠状和矢状断层影像清晰，正常志愿者（正常进食）可见脑和心肌显影，膀胱内放射性较多。２例恶性肿瘤患者的６处病变浓聚１８ＦＦＤＧ。２例恶性肿瘤患者手术和化疗后无复发征，显像阴性。２例良性病变处未见１８ＦＦＤＧ浓集。１例陈旧性心肌梗塞患者１８ＦＦＤＧ心肌断层显像与９９ｍＴｃ甲氧基异丁基异腈心肌血流灌注显像匹配良好。正常心肌显影与否受葡萄糖负荷的影响。８例脑皮质横断影像良好，基底节和丘脑影像有时尚欠清晰。初试结果表明，该ＰＥＴ仪相当于至今尚在国外广泛使用的８０年代中期４环／７层ＰＥＴ仪水平，但具有９０年代ＰＥＴ仪全身整体冠状和矢状断层显像的功能，可用于全身肿瘤显像、心肌活性判断和功能性癫痫灶术前定位，但仪器操作性能和软件功能尚需进一步完善。

PURPOSE To test the preliminary clinical performance of 4 rings/7 slices, AFOV 8 cm PET scanner made in China. METHODS Based on phantom test and animal study, PET imaging were performed on a normal volunteer and 7 patients 1 5 hours after intravenous injection of 370MBq of 18 F FDG. The acquisition time of whole body imaging for adult was 1 5 hours (11 bed position), whereas myocardium and brain imaging was 0 5 hours (2～3 bed position). RESULTS Φ 1～3 cm positive and negative foci could be displayed in phantom. 8 cases of coronal and sagital whole body tomographic images were clearly demonstrated. Brain, myocardium and bladder were significantly displayed in normal volunteer with normal food and drink. 6 malignant lesions of 2 patients concentrated 18 F FDG significantly and 2 benign lesions of 2 patients did not concentrated it. Recurrence and metastasis were excluded in 2 patients with carcinoma after operation and chemotherapy. Whether normal myocardium display or not were dependent on glucose loading. 18 F FDG myocardium images matched well with 99m Tc MIBI myocardial perfusion images in a patient with remote myocardial infarction. Cerebral cortex images well visualized in all subjects. CONCLUSIONS [WT5”BZ]The performance of this PET scanner showed that it reached the level of middle stage of 8th decade's 4 rings/7 slices PET and possessed the coronal and sagital whole body tomographic function of 9th decade's PET. It can be used in whole body tumor imaging, myocardial viability evaluation and preoperation localization of functional epileptic foci, but operating and software function should be improved.