A case report of a neonate with Arnold Chiari II malformation

Abstract

Chiari malformations are structural defects in the cerebellum that are characterized by the downward displacement of one or both cerebellar tonsils through the foramen magnum. A case report of a female neonate with clinical features of Chiari II malformation is presented. The diagnosis of this condition was made through a combination of clinical and radiological features. In this case, the diagnosis was confirmed by a noncontrast computed tomography (CT) scan of the brain and multiplanar brain magnetic resonance imaging (MRI).

Keywords: Arnold Chiari malformation; CT; Hydrocephalus; MRI; Myelomeningocele.

Fig. 1

Demonstrate axial, coronal and sagittal multiplanar reconstruction of brain CT without contrast of the neonate showing abnormal small posterior fossa with downward cerebellar tonsil and vermis herniation through the foramen magnum. Effaced prepontine cistern and cerebellum-pontine angle cistern with attenuated fourth ventricle and subsequent supratentorial hydrocephalus.

Fig. 2

Axial T1, coronal T2, and sagittal T1 MRI shows supra-tentorial hydrocephalus likely related to fourth ventricle outlet obstruction. Findings are consistent with Arnold-Chiari Malformation type II.