Intractable epilepsy following radiosurgery for arteriovenous malformation

Area of Science:

• Neurosurgery
• Neurology
• Epileptology

Background:

• Radiosurgery, including gamma knife surgery (GKS), is a common treatment for deep brain arteriovenous malformations (AVMs).
• While generally effective in AVM obliteration and seizure reduction, the long-term neurological sequelae require ongoing evaluation.
• Previous reports have not documented intractable epilepsy post-radiosurgery for AVMs.

Observation:

• A patient developed intractable epilepsy and mesial temporal sclerosis (MTS) after undergoing GKS for a right parietotemporooccipital AVM.
• Seizure frequency and severity escalated over two years, despite multiple antiepileptic drug regimens.
• Video-electroencephalography confirmed seizure origin from the right posterior quadrant, with MRI revealing both the AVM and MTS.

Findings:

• Successful surgical resection of the AVM and right temporal lobectomy resulted in complete seizure freedom for over a year.
• This case suggests a potential association between GKS for AVMs and the subsequent development of intractable epilepsy and MTS.
• The findings challenge the assumption that radiosurgery is uniformly safe regarding long-term seizure control.

Implications:

• Neurosurgeons and neurologists should consider the risk of developing intractable epilepsy and MTS following radiosurgery for AVMs.
• Further research is warranted to elucidate the mechanisms underlying this potential complication.
• This case underscores the importance of comprehensive long-term patient monitoring after radiosurgical interventions for brain AVMs.