O'Brien T J, Brinkmann B H, Mullan B P, So E L, Hauser M F, O'Connor M K, Hung J, Jack C R
Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA.
J Neurol Neurosurg Psychiatry. 1999 Mar;66(3):331-9. doi: 10.1136/jnnp.66.3.331.
Most studies that clinically validated peri-ictal SPECT in intractable partial epilepsy had used technetium-99m-hexamethylpropylene amine oxime (99mTc-HMPAO or 99mTc-exametazime) as the radiopharmaceutical. Because of some theoretical advantages, technetium-99m-ethyl cysteinate diethylester (99mTc-ECD or 99mTc-bicisate) is increasingly being used instead. This study compares unstabilised 99Tc-HMPAO and 99mTc-ECD in the performance of peri-ictal SPECT in partial epilepsy.
The injection timing and localisation rates in 49 consecutive patients with partial epilepsy who had peri-ictal injections with unstabilised 99mTc-HMPAO were compared with 49 consecutive patients who had peri-ictal injections with 99mTc-ECD. Quantitative cortical/subcortical and cortical/extracerebral uptake ratios were also compared. Subtraction SPECT coregistered to MRI (SISCOM) was performed in patients whose interictal SPECTS were available.
In the 99mTc-ECD patients, the latency from seizure commencement to injection was shorter (median 34 v 80 seconds, p<0.0001) and there was a lower rate of postictal injections (16.3% v 57.1%, p<0.0001). The cortical/extracerebral and cortical/subcortical uptake ratios were greater in the 99mTc-ECD images (median 5.0 v 3.6, and 2.5 v 2.2 respectively; both p<0.005), but the relative peri-ictal increase in uptake in the cortical focus did not differ significantly (median 37.0% v 37.0%; p>0.05). Blinded review of the SISCOM images were localising in a higher proportion of the 99mTc-ECD patients (40/45 (88.9%) v 25/37 (67.6%), p<0.05), and had a better concordance with EEG, MRI, and with the discharge diagnosis.
99mTc-ECD compares favourably with unstabilised 99mTc-HMPAO as a radiopharmaceutical for peri-ictal SPECT studies. Its use results in earlier injections and less frequent postictal injections than unstabilised 99mTc-HMPAO, thereby enhancing the sensitivity and the specificity of peri-ictal SPECT for the localisation of intractable partial epilepsy.
大多数在临床中验证发作期单光子发射计算机断层扫描（SPECT）用于难治性部分性癫痫的研究都使用锝-99m-六甲基丙烯胺肟（99mTc-HMPAO或99mTc-依沙美肟）作为放射性药物。由于一些理论优势，锝-99m-二乙半胱氨酸乙酯（99mTc-ECD或99mTc-比西酸）正越来越多地被使用。本研究比较了不稳定的99mTc-HMPAO和99mTc-ECD在部分性癫痫发作期SPECT中的表现。
将49例连续接受不稳定99mTc-HMPAO发作期注射的部分性癫痫患者的注射时机和定位率，与49例连续接受99mTc-ECD发作期注射的患者进行比较。还比较了皮质/皮质下和皮质/脑外摄取率。对发作间期SPECT可用的患者进行与磁共振成像（MRI）配准的减影SPECT（SISCOM）检查。
在99mTc-ECD组患者中，从癫痫发作开始到注射的延迟时间更短（中位数34秒对80秒，p<0.0001），发作后注射率更低（16.3%对57.1%，p<0.0001）。99mTc-ECD图像中的皮质/脑外和皮质/皮质下摄取率更高（中位数分别为5.0对3.6和2.5对2.2；均p<0.005），但皮质病灶中发作期摄取的相对增加无显著差异（中位数37.0%对37.0%；p>0.05）。对SISCOM图像的盲法评估显示，99mTc-ECD组患者中定位的比例更高（40/45（88.9%）对25/37（67.6%），p<0.05），并且与脑电图、MRI以及放电诊断的一致性更好。
作为发作期SPECT研究的放射性药物，99mTc-ECD与不稳定的99mTc-HMPAO相比具有优势。与不稳定的99mTc-HMPAO相比，使用它可实现更早注射且发作后注射频率更低，从而提高发作期SPECT对难治性部分性癫痫定位的敏感性和特异性。
