Abstracts

Rationale: Hemimegalencephaly is associated with a number of neurocutaneous findings but association with craniosynostosis has previously been reported, to our knowledge, only once in the literature. That patient had right coronal, sagittal, and lambdoid suture synostoses, hemimegalencephaly and febrile seizures (Am J Med Genet A. 2011 Jan;155A(1):207-14). Here, we report a case of metopic suture craniosynostosis with progressive hemimegalencephaly, eventually requiring synostosis surgery and infantile spasms.  Methods: Retrospective case review of records of noncontrast CT, MRI and Video EEG studies. Results: This, now 21-month-old previously full-term male, was referred at the age of 3.5 months due to single episodes of arm jerking with eyelid blinking. These episodes lasted a few seconds, did not cluster, and occurred a few times per day. His history was notable for progressive trigonocephaly, which prompted a noncontrast brain CT at 3 months of age and ultimately required surgical correction. CT imaging according to the craniosynostosis protocol confirmed metopic synostosis. Other sutures were normal. On retrospective review, asymmetry of the hemispheres was appreciated. Video-EEG showed left sided discharges interictally as well as during the above episodes and no hypsarrhythmia. MRI revealed generalized increased volume of the left hemisphere, as well as left-sided pachygyria and white matter abnormalities.  He was initially started on topiramate with plans for frequent and close clinical and EEG follow up. Over the next few weeks he developed multiple daily total body infantile spasms. Video EEG documented asymmetric hypsarrhythmia and confirmed the events to be infantile spasms. The spasms were subsequently refractory to ACTH, vigabatrin, topiramate, valproic acid, and clobazam. At the age of 7 months, he underwent left functional hemispherectomy which rendered him seizure free.  Conclusions: Physicians evaluating patients with craniosynostosis need to be aware of the possible, albeit rare, association between craniosynostosis and hemimegalencephaly. Skull imaging should be carefully reviewed for signs of hemispheric asymmetry, and an MRI should be performed in cases where asymmetry exists. Funding: No funding