Lewis A J, Simon E M, Barkovich A J, Clegg N J, Delgado M R, Levey E, Hahn J S
Stanford University School of Medicine and Lucile Packard Children's Hospital, CA, USA.
Neurology. 2002 Dec 24;59(12):1860-5. doi: 10.1212/01.wnl.0000037483.31989.b9.
The middle interhemispheric variant (MIH) is a subtype of holoprosencephaly (HPE) in which the posterior frontal and parietal areas lack midline separation, whereas more polar areas of the cerebrum are fully cleaved. While the neuroradiologic features of this subtype have been recently detailed, the clinical features are largely unknown.
To present the clinical manifestations of MIH and to compare them with classic subtypes (alobar, semilobar, and lobar) of HPE.
The authors evaluated 15 patients with MIH in a multicenter study. Neuroimaging and clinical data were collected and correlated. They compared the data with those of 68 patients who had classic HPE.
The frequency of endocrinopathy in MIH (0%) was lower compared with the classic subtypes (72%) (p < 0.0001). This correlated with the lack of hypothalamic abnormalities. The percentage of patients with seizures (40%) did not significantly differ from classic HPE. Spasticity was the most common motor abnormality, seen in 86% of MIH patients, similar to other subtypes. The frequency of choreoathetosis in MIH (0%) was lower than that for semilobar HPE (41%) (p < 0.0039). This correlated with the lack of caudate and lentiform nuclei abnormalities. Developmental functions, including mobility, upper-extremity function, and language, of the MIH group were similar to the least severe classic type, lobar HPE.
MIH is a recognizable variant of HPE with differing clinical prognosis. Similar to the lobar subtype by functional measures, MIH differs from classic HPE by the absence of endocrine dysfunction and choreoathetosis.
大脑半球间变异型（MIH）是全前脑畸形（HPE）的一种亚型，其中额后部和顶叶区域缺乏中线分离，而大脑更极向的区域完全分开。虽然该亚型的神经放射学特征最近已有详细描述，但临床特征在很大程度上尚不清楚。
介绍MIH的临床表现，并将其与HPE的经典亚型（无叶型、半叶型和叶型）进行比较。
作者在一项多中心研究中评估了15例MIH患者。收集并关联了神经影像学和临床数据。他们将这些数据与68例患有经典HPE的患者的数据进行了比较。
与经典亚型（72%）相比，MIH患者内分泌病的发生率（0%）较低（p<0.0001）。这与下丘脑无异常有关。癫痫患者的百分比（40%）与经典HPE无显著差异。痉挛是最常见的运动异常，在86%的MIH患者中可见，与其他亚型相似。MIH患者舞蹈手足徐动症的发生率（0%）低于半叶型HPE患者（41%）（p<0.0039）。这与尾状核和豆状核无异常有关。MIH组的发育功能，包括运动能力、上肢功能和语言能力，与最不严重的经典类型叶型HPE相似。
MIH是一种具有不同临床预后的可识别的HPE变异型。通过功能测量，MIH与叶型亚型相似，但与经典HPE不同之处在于不存在内分泌功能障碍和舞蹈手足徐动症。
