This report demonstrates a left pontine cavernous hemangioma as a likely cause of new onset seizures in a 37 year old female presenting with Millard-Gubler syndrome (MGS)

Cavernous hemangiomas (CH) are benign vascular tumors most commonly found supratentorially but may occur throughout the CNS. Approximately 20% occur in the brainstem. Most CH are able to be resected but brain stem CH prove a challenge due to the high density of nuclei and nerve fibers in the region. CH in the caudal pons can lead to MGS, an ipsilateral facial and abducens nerve palsy with contralateral hemiplegia due to corticospinal tract compression. Management usually involves surgery.

Case report and literature review. This 37 year old female first presented in 2010 with right lower extremity weakness and CN VI palsy. In 2011 she developed right hemiparesis, dysarthria, ataxia and a left CN V, VII, and VIII palsy. MRI showed a left pontine cavernous hemangioma. The next 10 years involved worsening hemiparesis and spasticity consistent with MGS. The patient declined surgical intervention throughout this time and was lost to follow-up. On 10/6/21 patient presented with a generalised tonic-clonic seizure followed by unresponsiveness for a short amount of time. Patient had no new findings on CT or CTA. EEG was normal indicating no cortical lesions that could cause the seizure. She was started on levetiracetam and had no additional seizure episodes.

Not Applicable

Brainstem cavernous hemangiomas cause multiple cranial nerve palsies and may present as MGS. New onset seizure activity is a rare potential long term complication of unresected pontine hemangioma. This is the first case of recorded MGS with concurrent onset of seizures due to pontine cavernous hemangioma.