Frame-based stereotactic resection of subcentimeter arteriovenous malformations in deep or eloquent regions of the brain: indications and technique with eight consecutive operations.

Subcentimeter arteriovenous malformations (AVMs) located in deep or eloquent cortex can be difficult to localize intraoperatively and safely remove with surgery. Nevertheless, surgical resection may be the optimal definitive treatment option available for select patients. In this communication, we describe our experience using a framed-based stereotactic approach for resecting these AVMs. The operative records of all AVMs treated at our institution over an 8-year period (1996-2004) were reviewed. 180 surgically treated AVMs were identified. From this group of patients, frame-based stereotaxy was used for 8 AVMs (4.4%) in 7 patients. The angiograms, operative reports, and medical records for these 7 patients were retrospectively reviewed with attention to neurological outcome, extent of AVM obliteration, and anatomic factors that impacted the decision to employ a frame-based stereotactic approach. All AVMs removed with this technique were less than 1 cm in diameter. Angiography confirmed complete resection in all cases. No new neurological deficits occurred in any patient. By providing highly accurate three-dimensional nidus localization and minimizing approach-related brain manipulation, frame-based stereotaxy reduces the morbidity associated with resection of subcentimeter AVMs located in deep or eloquent regions of the brain. This technique makes a definitive surgical cure available to patients who otherwise would only be considered for radiosurgery.