Neuroradiologic Features ofCASKMutations

J Takanashi,S Hirai,A.J Barkovich,H Arai,J Inazawa,N Okamoto,S Hayashi,S Nabatame

doi:10.3174/ajnr.a2173

Abstract

Mutations of the CASK gene are associated with X-linked mental retardation with microcephaly and disproportionate brain stem and cerebellar hypoplasia in females. The areas of the cerebrum, corpus callosum, pons, midbrain, and cerebellar vermis and hemisphere and a ratio of cerebrum/corpus callosum areas were measured in 5 female patients with CASK mutations, 67 female controls, and 5 patients with pontine hypoplasia. MR imaging in patients with CASK mutations revealed a normal size of the corpus callosum and a low ratio of the cerebrum/corpus callosum with a reduced area of the cerebrum, pons, midbrain, and cerebellar vermis and hemispheres. The 5 patients with pontine hypoplasia showed thinning of the corpus callosum and a high ratio of the cerebrum/corpus callosum, irrespective of the size of the cerebrum. The normal size of the corpus callosum, which gives an impression of callosal thickening at first glance, may be an imaging clue to detect patients with CASK mutations.

Highlights

Neuroradiologic Features of CASK MutationsSUMMARY: Mutations of the CASK gene are associated with X-linked mental retardation with microcephaly and disproportionate brain stem and cerebellar hypoplasia in females
We report MR imaging findings with volumetric data in 5 female patients with CASK mutations to determine whether they have characteristic imaging findings compared with other patients with pontine hypoplasia
The midline corpus callosum area was within the normal range in all 5 patients with CASK mutations (Figs 2B and 3B), leading to an impression of thickening compared with the small cerebrum

Summary

Neuroradiologic Features of CASK Mutations

SUMMARY: Mutations of the CASK gene are associated with X-linked mental retardation with microcephaly and disproportionate brain stem and cerebellar hypoplasia in females. The areas of the cerebrum, corpus callosum, pons, midbrain, and cerebellar vermis and hemisphere and a ratio of cerebrum/ corpus callosum areas were measured in 5 female patients with CASK mutations, 67 female controls, and 5 patients with pontine hypoplasia. MR imaging in patients with CASK mutations revealed a normal size of the corpus callosum and a low ratio of the cerebrum/corpus callosum with a reduced area of the cerebrum, pons, midbrain, and cerebellar vermis and hemispheres. The normal size of the corpus callosum, which gives an impression of callosal thickening at first glance, may be an imaging clue to detect patients with CASK mutations. ABBREVIATIONS: CASK ϭ calcium/calmodulin-dependent serine protein kinase; CINAP ϭ CASK interacting nucleosome assembly protein; PEHO ϭ progressive encephalopathy, edema, hypsarrhythmia, and optic atrophy; TBR1 ϭT-brain-1; RELN ϭ reelin

PEDIATRICS CLINICAL REPORT

Discussion

Conclusions