Neuroimaging Findings and Outcome in Pediatric Cephalocele with Chiari II-Like Stigmata

Author(s): Rida Salman, Nilesh K. Desai, Stephen F. Kralik, Michael A. Belfort, Livja Mertiri, Gunes Orman , Thierry A.G.M. Huisman

Background and Objective: There is a known association between Chiari malformation and occipital encephalocele. We aim to identify the frequency of Chiari II-like neuroimaging findings and radiologic and clinical outcomes after surgical repair in pediatric patients with cephalocele.

Materials and Methods: Retrospective review of brain CT and MRI of children with cephalocele between 1/1/2011-11/30/2021 was performed in consensus. Demographic, clinical and surgical data were recorded. The location and size of defect, type of herniated tissue, posterior fossa size, hindbrain herniation (HH) into the upper spinal canal, tectal beaking (TB), cortical malformation (CM), corpus callosum abnormalities and hydrocephalus were collected. Clinical and radiologic outcome were noted.

Results: Twenty-six patients were included (19 females, 73%) with mean age at diagnosis 121+/-565 days. Neuroimaging showed occipital defect in 23 (89%), meningoencephalocele in 18 (69%) and small posterior fossa in 18 (69%). HH was present in 12 (46%), TB in 5 (19%) and CM in 11 (42%). No hydrocephalus in 15 (58%), normal corpus callosum in 11 (42%) patients. One patient did not have documented clinical follow-up note. Sixteen (64%) had good outcome. No statistically significant difference in clinical outcome regarding the radiologic findings at diagnosis. Small posterior fossa (p=0.04) and presence of HH (p=0.001) on initial imaging was associated with postsurgical HH. Defect location (p=0.03) and presence of hydrocephalus (p=0.01) on initial imaging was associated with postsurgical hydrocephalus.

Conclusions: Less than half of cephalocele patients demonstrate Chiari II-like findings on initial imaging. Variable changes in HH and hydrocephalus occur following surgery suggesting that it is an acquired deformity sequence.