巨脑回和无脑回畸形的CT、MRI诊断

结合巨脑回和无脑回畸形的病理特点,研究两种病变的CT、MRI表现特征,以评价两种影像学检查方法该病变的诊断价值。回顾分析15例巨脑回和无脑回畸形的临床和影像资料,其中CT检查12例,MRI检查3例。结果显示：CT、MRI显示无脑回畸形7例,双侧全大脑半球的巨脑回畸形5例,单侧大脑半球的局限性巨脑回畸形3例。病变在CT、MRI上表现为皮层增厚,白质减少;脑表面扁平光滑,或仅有少许宽大脑回和浅小脑沟;脑灰—白质界面光滑。在12例全脑受累的病变中,侧裂浅小,脑岛暴露,大脑中动脉侧裂段贴近颅骨内板走行,大脑轮廓星哑铃形或“8”形。伴随的脑发育异常包括灰质异位(5例),Ⅰ型脑裂畸形(2例),胼胝体发育不良(1例)。本研究表明：巨脑回和无脑回畸形的病理改变具有特征,CT和MRI是评价这些病理特征的优良检查方法。

CT and MR Imaging of Pachygyria and Agyria

The CT and MRI manifestations of pachygyria and agyria are presented with a review of the pathological features of the disorders and an evaluation of the diagnostic value of both imaging modalities. 15 cases were analysed retrospectively; of them, 12 were examined with CT and 3 with MRI. The analyses confirm 7 cases with agyria, 5 with pachygyria of bilateral cerebral hemisphere and 3 with limited pachygyria of unilateral hemisphere. On CT and MRI of the whole lesions, the cortex is thickened and the white matter is reduced in proportion. The surface of the brain remains flat and smooth or shows only a few broad gyri and shallow sulci. The border between gray and white matter is smooth. In 12 patients with agyria and pachygyria of the whole brain, the sylvian fissures are shallow, and insulae are exposed. The middle cerebral arteries course superficially along sylvian grooves close to the inner table of the skull. The cerebral contour is "hourglass" or "figure of eight". Associated brain anomalies include the heterotopia of gray matter in 5 cases, the schizencephaly (type I) in 2 cases and the agenesis of the corpus callosum in one case. In conclusion, the pathological changes of pachygyria and agyria are characteristics. CT and MRI are excellent modalities to evaluate these pathological features.