Defining ideal middle cerebral artery bifurcation aneurysm size for Woven EndoBridge embolization
Authors: Adeeb Nimer , Musmar Basel , Salim Hamza Adel , Aslan Assala , Alla Anika , Cancelliere Nicole M. , McLellan Rachel M. , Algin Oktay , Ghozy Sherief , Dibas Mahmoud , Lay Sovann V. , Guenego Adrien , Renieri Leonardo , Carnevale Joseph , Saliou Guillaume , Mastorakos Panagiotis , Naamani Kareem El , Shotar Eimad , Premat Kevin , Möhlenbruch Markus , Kral Michael , Doron Omer , Chung Charlotte , Salem Mohamed M. , Lylyk Ivan , Foreman Paul M. , Vachhani Jay A. , Shaikh Hamza , Župančić Vedran , Hafeez Muhammad U. , Catapano Joshua S. , Waqas Muhammad , Tutino Vincent M. , Ibrahim Mohamed K. , Mohammed Marwa A. , Ozates M. Ozgur , Ayberk Giyas , Rabinov James D. , Ren Yifan , Schirmer Clemens M. , Piano Mariangela , Kühn Anna L. , Michelozzi Caterina , Elens Stéphanie , Starke Robert M. , Hassan Ameer , Ogilvie Mark , Nguyen Anh , Jones Jesse , Brinjikji Waleed , Nawka Marie T. , Psychogios Marios , Ulfert Christian , Diestro Jose Danilo Bengzon , Pukenas Bryan , Burkhardt Jan-Karl , Domingo Ricardo A. , Huynh Thien , Martinez-Gutierrez Juan Carlos , Essibayi Muhammed Amir , Sheth Sunil A. , Spiegel Gary , Tawk Rabih G. , Lubicz Boris , Panni Pietro , Puri Ajit S. , Pero Guglielmo , Nossek Erez , Raz Eytan , Killer-Oberfalzer Monika , Griessenauer Christoph J. , Asadi Hamed , Siddiqui Adnan , Brook Allan L. , Altschul David , Ducruet Andrew F. , Albuquerque Felipe C. , Regenhardt Robert W. , Stapleton Christopher J. , Kan Peter , Kalousek Vladimir , Lylyk Pedro , Boddu Srikanth , Knopman Jared , Aziz-Sultan Mohammad A. , Tjoumakaris Stavropoula I. , Clarençon Frédéric , Limbucci Nicola , Cuellar-Saenz Hugo H. , Jabbour Pascal M. , Mendes Pereira Vitor , Patel Aman B. , Dmytriw Adam A. 
Published: October 2024

OBJECTIVE
The Woven EndoBridge (WEB) device was approved to treat wide-necked bifurcation aneurysms. The device is designed as an intrasaccular flow disruptor covering aneurysm widths up to 10 mm. Although prior studies combined all aneurysm sizes, it is known that aneurysms behave differently in response to endovascular treatment based on their size. Therefore, the authors’ objective was to identify ideal middle cerebral artery (MCA) aneurysm width and neck sizes most suitable for WEB treatment.

METHODS
The WorldWideWEB consortium is a large multicenter retrospective database that analyzes intracranial aneurysms treated with the WEB device. In this study, all unruptured MCA bifurcation aneurysms with available measurements were included. Cutoff values based on aneurysm width and neck in relation to aneurysm occlusion status were measured using the receiver operating characteristic (ROC) curve. Propensity score matching (PSM) was then used to compare treatment outcomes between aneurysms smaller and larger than the cutoff value for both width and neck size.

RESULTS
The ideal cutoff values for MCA bifurcation aneurysm width and neck were 6.1 mm and 4.6 mm, respectively. On PSM, 87 matched pairs were compared based on width size (≤ 6.1 mm and > 6.1 mm), and 77 matched pairs were compared based on neck size (≤ 4.6 mm and > 4.6 mm). There was a significant difference in adequate aneurysm occlusion between aneurysms smaller and larger than those cutoff values for both widths (93% vs 76%, p = 0.0017) and neck sizes (90% vs 70%, p = 0.0026). The retreatment rate was also significantly higher for larger aneurysms in both parameters.

CONCLUSIONS
This study shows that MCA bifurcation aneurysms ≤ 6.1 mm in width and ≤ 4.6 mm in neck size are significantly better candidates for WEB treatment, leading to improved occlusion status and reduced retreatment rate, which are important considerations when using WEB devices.