Chiari malformation I and autism spectrum disorder: an underrecognized coexistence

Patients with symptomatic Chiari malformation Type I (CM-I) frequently present with headaches, neck pain, difficulty swallowing, and balance disturbances. In children with autism spectrum disorder (ASD), diagnosing CM-I can be a challenging task. Moreover, even if symptomatic, some patients do not undergo further evaluation or management, as their presentations are attributed to autism and its myriad symptoms. Therefore, cranial MRI findings were reviewed after evaluating and treating patients with coexisting ASD and CM-I. In this paper, the authors report on 5 children with ASD and symptomatic CM-I, including their clinical presentation, imaging studies, management, and outcomes, and discuss the likely underrecognized coexistence of these conditions.

All pediatric patients with ASD and cranial MRI conducted for any reason in the period from 1999 to 2013 were considered for analysis. All cases with concomitant symptomatic CM-I were eligible for this retrospective analysis.

One hundred twenty-five pediatric patients diagnosed with ASD had undergone MRI, and 9 of them had evidence of cerebellar tonsillar herniation. Five patients were symptomatic and underwent suboccipital craniectomy, a C-1 or a C-1 and C-2 laminectomy, and duraplasty with bovine pericardium or Type I collagen allograft. There were no intraoperative complications. All patients showed symptom improvement and/or resolution of presenting symptoms, which included headache, dysphasia, speech, and irritability.

There is no identified cause of autism. Children with ASD can be difficult to assess specifically in a neurological examination. Thus, cranial MRI considered when completing a comprehensive diagnostic evaluation. While cranial MRI is not a routine part of ASD evaluation, this study demonstrates that CM-I and ASD may coexist and be underrecognized. The study reinforces the importance of a comprehensive medical evaluation designed to elucidate neurological findings in children with impaired communication abilities and suggests the judicious use of neuroimaging.