^(99m)Tc-MIBI脑显像诊断脑肿瘤的初步应用

The preliminary application of 99m Tc MIBI SPECT in the diagnosis of brain tumor

目的探讨９９ｍＴｃ甲氧基异丁基异腈（ＭＩＢＩ）脑显像对脑肿瘤的诊断价值。方法对８例正常对照者和３１例脑肿瘤患者分别行９９ｍＴｃＭＩＢＩ脑血流显像和断层显像。脑血流显像观察病变部位血液供应情况；断层显像分别于注射后１５～３０分钟（早期相）和２～３小时（延迟相）进行，观察病变部位摄取９９ｍＴｃＭＩＢＩ的情况，并在横断面或冠状面图像上，分别计算早期相和延迟相肿瘤部位（Ｔ）与对侧（Ｃ）和脉络丛（ＣＰ）单位象素的放射性计数比值（Ｔ／Ｃ和Ｔ／ＣＰ），进行半定量分析。结果血流显像脑肿瘤组１２例异常。断层显像所有受检者早期相和晚期相均可见ＣＰ部位放射性浓集，正常对照组脑实质内无放射性浓集；脑肿瘤组２０例显像阳性，肿瘤部位放射性异常浓集，Ｔ／Ｃ及Ｔ／ＣＰ较对照组高。９９ｍＴｃＭＩＢＩ检出脑肿瘤的灵敏度和特异性分别为６４５％和１００％。

Purpose To evaluate the value of the brain 99m Tc MIBI SPECT for detecting brain tumor Methods 31 patients with brain tumor and 8 normal controls underwent both dynamic imaging and SPECT, followed by semiquantitative analysis SPECT included early and delay phases The early and delay SPECT were acquired 15～30min and 2～3hr after injection of 555～925MBq 99m Tc MIBI respectively SPECT semiquantitative assessment of tracer uptake were made using a ratio of radioactivity in tumor containing areas compared to contralateral areas (T/C) and to choroid plexus (T/CP) Results 12 out of 31 patients were abnormal in dynamic study It was observed that there was consistant and prominent uptake of 99m Tc MIBI in the normal choroid plexus The radioactivity was observed in 20 out of 31 brain tumors The sensitivity and specificity were 64 5% and 100% respectively Conclusions The brain 99m Tc MIBI SPECT has clinical significance in detecting brain tumor