Moroni I, Bugiani M, Bizzi A, Castelli G, Lamantea E, Uziel G
Department of Child Neurology, Istituto Nazionale Neurologico C. Besta, Milano, Italy.
Neuropediatrics. 2002 Apr;33(2):79-85. doi: 10.1055/s-2002-32372.
In childhood mitochondrial encephalopathies the common MRI features are bilateral symmetric abnormalities in basal nuclei and brainstem. The presence of diffuse white matter abnormality has been described only in a few cases. Among a series of 110 children with mitochondrial encephalopathies, 8 patients with MR imaging consistent with a leukoencephalopathy were retrospectively evaluated. Diagnosis was based on the recognition of the biochemical defect in muscle homogenate. H-MR spectroscopic imaging was performed in six of them. Biochemical analysis demonstrated a defect of respiratory chain complexes in six patients: complex I in two cases, complex II in two, complex IV in one, multiple complexes defect in one. Pyruvate dehydrogenase deficiency was demonstrated in two patients. MRI showed severe involvement of the brain white matter without significant basal nuclei or brainstem abnormalities. Two patients developed large cystic areas since onset; in two others progressive vacuolisation of affected white matter was seen later in the course of the disease. One patient with pyruvate dehydrogenase deficiency also presented with a diffuse cortical polymicrogyria. H-MR spectroscopic imaging showed a decrease of N-acetylaspartate, choline and creatine with lactate accumulation in five patients, and was normal in one. These findings suggest that mitochondrial disorders should be included in the differential diagnosis of white matter disorders.
在儿童线粒体脑病中，常见的MRI特征是基底核和脑干的双侧对称性异常。仅在少数病例中描述过弥漫性白质异常的存在。在一系列110例线粒体脑病患儿中，对8例MRI表现符合白质脑病的患儿进行了回顾性评估。诊断基于对肌肉匀浆中生化缺陷的识别。其中6例进行了氢质子磁共振波谱成像（H-MR spectroscopic imaging）。生化分析显示6例患者存在呼吸链复合体缺陷：2例为复合体I缺陷，2例为复合体II缺陷，1例为复合体IV缺陷，1例为多种复合体缺陷。2例患者证实有丙酮酸脱氢酶缺乏。MRI显示脑白质严重受累，基底核和脑干无明显异常。2例患者起病后出现大的囊性区域；另外2例在疾病过程中较晚出现受累白质的进行性空泡化。1例丙酮酸脱氢酶缺乏的患者还表现为弥漫性皮质多小脑回畸形。H-MR光谱成像显示5例患者N-乙酰天门冬氨酸、胆碱和肌酸减少，伴有乳酸蓄积，1例正常。这些发现提示线粒体疾病应纳入白质疾病的鉴别诊断。
