Coexistent arteriovenous malformation and hippocampal sclerosis

Area of Science:

• Neurology
• Neurosurgery
• Pathology

Background:

• Cavernous angiomas are known to be associated with medically intractable epilepsy.
• Co-occurrence of secondary pathologies like focal cortical dysplasia or hippocampal sclerosis with cavernomas is rare.
• Arteriovenous malformations (AVMs) are infrequently reported in conjunction with epilepsy.

Observation:

• A 56-year-old woman with a history of staring spells since age 24 presented with AVM hemorrhage.
• Following Gamma Knife radiosurgery for the AVM, she developed refractory epilepsy.
• MRI revealed right hippocampal atrophy, consistent with hippocampal sclerosis.

Findings:

• Histopathology confirmed an arteriovenous malformation with vascular sclerosis and calcification.
• The resected hippocampus showed significant neuronal loss and gliosis in the CA1 region (International League Against Epilepsy type 2 hippocampal sclerosis).
• This represents a novel association of AVM and hippocampal sclerosis in a patient with intractable epilepsy.

Implications:

• This case expands the understanding of rare neurological comorbidities contributing to epilepsy.
• It underscores the importance of thorough investigation in refractory epilepsy cases with vascular lesions.
• Further research may elucidate sharedPathogenic mechanisms or diagnostic challenges in such complex cases.