Reference Centre for Rare Epilepsies, Department of Paediatric Neurology, Hôpital Necker-Enfants malades, APHP, Paris, France; Inserm, U663, Paris, France; University Paris Descartes, CEA, Gif sur Yvette, France.
Dev Med Child Neurol. 2013 Dec;55(12):1150-8. doi: 10.1111/dmcn.12233. Epub 2013 Aug 8.
Hemiconvulsion-hemiplegia syndrome (HHS) is a rare severe epilepsy of infancy consisting of unilateral convulsive status epilepticus immediately followed by transient or lasting ipsilateral hemiplegia. HHS may occur either in patients with previous brain pathology or without any identified cause, so-called 'idiopathic HHS'.
We retrospectively analysed clinical and MRI longitudinal findings of a series of 10 patients (six females, four males) presenting with HHS. Age at the study inclusion ranged from 2 years 6 months to 15 years (mean of 5 y 10 mo, median 4 y 2 mo). After defining magnetic resonance imaging (MRI) features as 'typical', i.e. strictly unilateral involvement, and 'atypical', i.e. bilateral, we compared clinical data from both groups. Cognitive level was assessed using Brunet-Lézine or Wechsler scales.
HHS occurred at a mean age of 20.5 months (range 8-48 mo). In all cases, status epilepticus lasted for more than 1 hour and was characterised by unilateral clonic seizures followed by ipsilateral hemiplegia (persistent in five patients). Two patients in this series died: the first from multi-organ failure 2 weeks after the status epilepticus and the other from a second episode of ipsilateral intractable febrile status epilepticus 3 years after the first episode. Early MRI (days 1-7 from status epilepticus) showed hemispheric cytotoxic oedema in all, extending to the contralateral side for one. T2 hyperintensity in the basal ganglia was disclosed in 70% of patients and in the hippocampus in 60%. After 1 month (in intermediate and chronic phases), all surviving patients but one showed hemispheric cortical atrophy corresponding to the regions involved during the early stage. Comparing clinical features of patients presenting with 'typical' features, to those with 'atypical' findings, the second group presented psychomotor delay before status epilepticus.
This series underlines the major value of early MRI for the prompt diagnosis of HHS, and shows that involvement of subcortical structures has been underestimated. Hippocampal involvement is not constant.
偏瘫性惊厥-偏瘫综合征（HHS）是一种罕见的婴儿期严重癫痫，由单侧惊厥性癫痫持续状态立即引起短暂或持久的同侧偏瘫。HHS 可能发生在有先前脑病史的患者中，也可能发生在没有任何明确病因的患者中，即所谓的“特发性 HHS”。
我们回顾性分析了 10 例 HHS 患者的临床和 MRI 纵向资料（6 例女性，4 例男性）。纳入研究的年龄为 2 岁 6 个月至 15 岁（平均 5 岁 10 个月，中位数 4 岁 2 个月）。在将磁共振成像（MRI）特征定义为“典型”，即严格单侧受累，和“非典型”，即双侧受累后，我们比较了两组的临床资料。认知水平使用 Brunet-Lézine 或 Wechsler 量表进行评估。
HHS 的发病年龄平均为 20.5 个月（8-48 个月）。在所有病例中，癫痫持续状态持续时间超过 1 小时，表现为单侧阵挛性癫痫发作，随后同侧偏瘫（5 例持续存在）。该系列中有 2 例患者死亡：第一例患者在癫痫持续状态后 2 周死于多器官衰竭，另一例患者在首次发作后 3 年死于同侧难治性发热性癫痫持续状态。早期 MRI（癫痫持续状态后 1-7 天）显示所有患者均有半球细胞毒性水肿，其中 1 例扩展至对侧。70%的患者基底节区 T2 高信号，60%的患者海马区 T2 高信号。1 个月后（在中期和慢性期），除 1 例患者外，所有存活患者均表现出与早期受累区域相对应的半球皮质萎缩。将表现为“典型”特征的患者的临床特征与表现为“非典型”特征的患者进行比较，后者在癫痫持续状态前存在精神运动发育迟缓。
本系列强调了早期 MRI 对 HHS 快速诊断的重要价值，并表明对皮质下结构的受累认识不足。海马受累并不常见。
