Department of Neurology, Sanjay Gandhi PGIMS, Lucknow, India.
Acta Trop. 2010 Dec;116(3):206-11. doi: 10.1016/j.actatropica.2010.08.007. Epub 2010 Sep 9.
There is paucity of studies regarding the utility of various conventional MRI sequences in the diagnosis of viral encephalitis. The present study evaluates the usefulness of various MRI sequences in acute viral encephalitis. 88 consecutive viral encephalitis patients, aged 2-72 years were subjected to clinical evaluation. Consciousness was assessed by Glasgow Coma Scale (GCS). Serum or cerebrospinal fluid (CSF) was analyzed for dengue, Japanese encephalitis (JE), herpes, measles, echo, coxsackie and polio viruses using ELISA or PCR. Cranial MRI was done and T1, T2, FLAIR and DW images were obtained. The MRI changes were correlated with type of encephalitis and duration of illness. All the patients had altered sensorium and 37 had seizures. 22 patients had JE, 9 had dengue, 8 had herpes simplex encephalitis (HSE), 2 had Epstein-Barr virus encephalitis (EBVE) and 47 had non-specific encephalitis. The median duration of MRI study from onset was 10 days. In JE (20/22), HSE (8/8), and EBVE (2/2), MRI abnormalities were more common compared to dengue (2/9) and non-specific (20/47) encephalitis. The MRI abnormalities were more common in FLAIR (57.1%) compared to T2 (52.9%), DWI (38.1%) and T1 (19.3%) sequences. The mean ADC value in JE patients was lower (974.0±110.85×10⁻⁶ mm²/s) than HSE (1024.33±485.76×10⁻⁶ mm²/s). Additional MRI lesions were seen in 12.6% cases on FLAIR sequence. FLAIR and T2 sequences were more sensitive in revealing abnormalities in viral encephalitis.
关于各种常规 MRI 序列在病毒性脑炎诊断中的应用价值的研究较少。本研究评估了各种 MRI 序列在急性病毒性脑炎中的应用价值。88 例连续病毒性脑炎患者，年龄 2-72 岁，接受临床评估。采用格拉斯哥昏迷量表（GCS）评估意识状态。采用酶联免疫吸附法或聚合酶链反应检测血清或脑脊液中登革热、日本脑炎（JE）、疱疹、麻疹、回声、柯萨奇和脊髓灰质炎病毒。行头颅 MRI 检查，获取 T1、T2、FLAIR 和 DW 图像。将 MRI 改变与脑炎类型和病程相关联。所有患者均有感觉改变，37 例有癫痫发作。22 例为 JE，9 例为登革热，8 例为单纯疱疹脑炎（HSE），2 例为 EBV 脑炎（EBVE），47 例为非特异性脑炎。从发病到 MRI 研究的中位时间为 10 天。在 JE（20/22）、HSE（8/8）和 EBVE（2/2）中，MRI 异常较登革热（2/9）和非特异性（20/47）脑炎更为常见。FLAIR（57.1%）的 MRI 异常较 T2（52.9%）、DWI（38.1%）和 T1（19.3%）序列更为常见。JE 患者的平均 ADC 值较低（974.0±110.85×10⁻⁶ mm²/s），低于 HSE（1024.33±485.76×10⁻⁶ mm²/s）。FLAIR 序列还发现 12.6%病例有额外的 MRI 病灶。FLAIR 和 T2 序列在揭示病毒性脑炎异常方面更敏感。
