Temporal Lobe Arteriovenous Malformations: Surgical Outcomes With a Focus on Visual Field Defects and Epilepsy

BACKGROUND:Temporal lobe arteriovenous malformations (AVMs) represent a subgroup of intracranial AVMs with particular characteristics and management issues. OBJECTIVE:To characterize the surgical outcomes of temporal lobe AVMs with emphasis on visual field deficits (VFDs) and seizures. METHODS:Between 1992 and 2008, 29 patients were operated on for temporal lobe AVMs. Patient data were retrospectively collected and analyzed. RESULTS:Twelve of 29 patients (41.4%) presented with seizures and 4 (13.7%) presented with VFDs. Postoperatively, 6 patients (24%) showed new VFDs and 2 improved, with a rate of preservation of full visual fields of 84%. Larger AVMs (> 3 cm) were significantly associated with postoperative VFD (P = .008). Epilepsy outcomes assessed by the Engel scale were as follows9 patients (75%) were in class I (seizure free), 1 patient (8.3%) was in class III, and 2 patients (16.6%) were in class IV (no change or worsening). Postoperative modified Rankin Scale outcomes were excellent (grade 0-1) in 18 patients, good (grade 2) in 7, and poor (grade 3-4) in 4. Older age at diagnosis correlated with a worse functional outcome (Spearman ρ = 0.369; P = .049). AVMs were totally removed in 27 of 29 patients (93.1%). Complete surgical excision was confirmed with angiography. Two patients needed reoperation for AVM remnant. Three patients had persistent hemiparesis (10.3% permanent morbidity). There was no mortality. CONCLUSION:Seizure control is usually underappreciated in the surgical management of AVMs. However, in temporal lobe AVMs, good outcomes with low morbidity and good visual field preservation can be accomplished. ABBREVIATIONS:AED, antiepileptic drugAVM, arteriovenous malformationmRS, modified Rankin ScaleVFD, visual field deficit