Thalamic Arteriovenous Malformations: Clinical Presentation, Angio-Architecture and Therapeutic Management:...

Assess the prevalence of thalamic AVM (tAVMs), their revealing conditions and angio-architectural features, as well as their therapeutic management.

Monocentric retrospective study (1998 to 2018) involving 748 consecutive patients with a brain AVM managed at the Pitié-Salpêtrière Hospital, from which tAVMs were retrieved. Revealing condition of the tAVMs was recorded. tAVMs' angio-architecture was systematically reviewed on angiographic examinations. The safety and effectiveness of treatments (conservative management and exclusion treatment) were evaluated based on clinical and angiographic criteria.

Twenty-two consecutive patients (9 males, mean age: 32 ± 14 years) with a tAVM were included (prevalence: 2.9%). tAVMs were revealed by a bleeding event in 86.4% of cases. The posterolateral choroidal artery was the most frequently observed arterial feeder in our series (71.4%). Associated aneurysm (nidal and/or pedicular) was observed in 36.4% of patients. The tAVMs' mean volume was 6.45 ± 12.8 ml. Venous drainage was in the deep venous system only in most cases (81%). Four patients received conservative management, 12 patients were treated by radiosurgery and 12 by embolization, with 6 patients (27.2%) who received both embolization and radiosurgery. Complete nidal occlusion was achieved in 33.3% of the patients who underwent angiographic follow-up. Two embolized patients (16.7%) suffered severe embolization-related complications, and 4 patients treated with radiosurgery (33.3%) suffered severe procedure related complication, all of which resolved without significant sequela.

Our results underline the safety of exclusion treatments by embolization and/or radiosurgery of tAVMs. Efficacy in terms of angiographic exclusion still needs to be demonstrated at long-term due to limited imaging follow-up.