Efficacy and safety of preoperative embolization in surgical treatment of brain arteriovenous malformations: a multicentre study with propensity score matching
Authors: Salim Hamza , Hamdan Dawoud , Adeeb Nimer , Kandregula Sandeep , Aslan Assala , Musmar Basel , Ogilvy Christopher S , Dmytriw Adam A , Abdelsalam Ahmed , Ataoglu Cagdas , Erginoglu Ufuk , Kondziolka Douglas , El Naamani Kareem , Sheehan Jason , Ironside Natasha , Kumbhare Deepak , Gummadi Sanjeev , Essibayi Muhammed Amir , Tos Salem M , Keles Abdullah , Muram Sandeep , Sconzo Daniel , Rezai Arwin , Alwakaa Omar , Pöppe Johannes , Sen Rajeev D , Baskaya Mustafa K , Griessenauer Christoph J , Jabbour Pascal , Tjoumakaris Stavropoula I , Atallah Elias , Riina Howard , Abushehab Abdallah , Swaid Christian , Burkhardt Jan-Karl , Starke Robert M , Sekhar Laligam N , Levitt Michael R , Altschul David J , Haranhalli Neil , McAvoy Malia , Abla Adib , Stapleton Christopher , Koch Matthew J , Srinivasan Visish M , Chen Peng Roc , Blackburn Spiros , Cochran Joseph , Choudhri Omar , Pukenas Bryan , Orbach Darren B , Smith Edward R , Moehlenbruch Markus , Mosimann Pascal J , Alaraj Ali , Aziz-Sultan Mohammad Ali , Patel Aman B , Yedavalli Vivek , Wintermark Max , Savardekar Amey , Cuellar Hugo H , Lawton Michael T , Morcos Jacques J , Guthikonda Bharat 
Published: February 2025

Background

Brain arteriovenous malformations (AVMs) are abnormal connections between feeding arteries and draining veins, associated with significant risks of haemorrhage, seizures and other neurological deficits. Preoperative embolization is commonly used as an adjunct to microsurgical resection, with the aim of reducing intraoperative complications and improving outcomes. However, the efficacy and safety of this approach remain controversial.

Methods

This study is a subanalysis of the Multicenter International Study for Treatment of Brain AVMs consortium. We retrospectively analysed 486 patients with brain AVMs treated with microsurgical resection between January 2010 and December 2023. Patients were divided into two groups: those who underwent microsurgery alone (n=245) and those who received preoperative embolization, followed by microsurgery (n=241). Propensity score matching was employed, resulting in 288 matched patients (144 in each group). The primary outcomes were rates of complete AVM obliteration and functional outcomes (measured by the modified Rankin Scale (mRS)). Secondary outcomes included complication rates, mortality, hospital length of stay and postsurgical rupture.

Results

After matching, the complete obliteration rate was 97% with no significant difference between the microsurgery-only group and the preoperative embolization group (p=0.12). The proportion of patients with an mRS score of 0–2 at the last follow-up was similar in both groups (83% vs 84%; p=0.67). The median hospital stay was significantly longer for the embolisation group (9 days vs 7 days; p=0.017). Complication rates (24% vs 22%; p=0.57) and mortality rates (4.9% vs 2.1%; p=0.20) were comparable between the two groups. No significant differences were observed in postsurgical rupture, recurrence or retreatment rates.

Conclusions

In this large multicentre study, preoperative embolization did not significantly improve AVM obliteration rates, functional outcomes or reduce complications compared with microsurgery alone.