{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,31]],"date-time":"2026-10-31T08:11:17Z","timestamp":1793434277222,"version":"4.5.0"},"reference-count":81,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"9","content-domain":{"domain":["www.ahajournals.org"],"crossmark-restriction":true},"short-container-title":["Stroke"],"published-print":{"date-parts":[[2025,9]]},"abstract":"<jats:p>Medium vessel occlusions represent a substantial proportion of patients with acute ischemic stroke. Recently presented randomized controlled trials, ESCAPE-MeVO (Endovascular Treatment to Improve Outcomes for Medium Vessel Occlusions), DISTAL (Endovascular Therapy Plus Best Medical Treatment [BMT] Versus BMT Alone for Medium Distal Vessel Occlusion Stroke), and DISCOUNT (Evaluation of Mechanical Thrombectomy in Acute Ischemic Stroke Related to a Distal Arterial Occlusion), did not demonstrate a clinical benefit of endovascular thrombectomy in distal and medium vessel occlusions, potentially generating uncertainty about optimal treatment strategies for medium vessel occlusions. Specifically, these results may lead clinicians to hesitate in performing endovascular thrombectomy for M2 occlusions, despite prior evidence indicating benefit in this subgroup. In this review, we critically examine current literature, focusing on anatomic and functional definitions of M2 segments, and highlight the significant heterogeneity in their classification. We place a particular emphasis on proximal as well as dominant M2 branches and the existing evidence, including observational studies, meta-analyses, and prior randomized trials. Additionally, we discuss methodological limitations and patient-selection biases of recent neutral trials, which may warrant caution in the broad application of their findings. Lastly, we propose recommendations for future research, emphasizing the need for refined patient-selection criteria to better identify subgroups most likely to benefit from endovascular thrombectomy, improved classification systems for M2 occlusions, and the exploration of adjunctive and alternative therapies.<\/jats:p>","DOI":"10.1161\/strokeaha.125.051578","type":"journal-article","created":{"date-parts":[[2025,8,25]],"date-time":"2025-08-25T18:00:41Z","timestamp":1756144841000},"page":"2819-2829","update-policy":"https:\/\/doi.org\/10.1161\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":18,"title":["Should We Stop Endovascular Treatment of M2 Occlusions?: A Critical Look at Recent Evidence"],"prefix":"10.1161","volume":"56","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1343-7389","authenticated-orcid":true,"given":"Amol","family":"Mehta","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY (A.M., D.G., J.F., J.M.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daryl","family":"Goldman","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY (A.M., D.G., J.F., J.M.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2998-8481","authenticated-orcid":true,"given":"Eytan","family":"Raz","sequence":"additional","affiliation":[{"name":"Department of Radiology and Neurosurgery, NYU Langone Health, New York, NY (E.R.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9013-6929","authenticated-orcid":true,"given":"Shashvat","family":"Desai","sequence":"additional","affiliation":[{"name":"HonorHealth Research and Innovation Institute, Scottsdale, AZ (S.D.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7426-3650","authenticated-orcid":true,"given":"Eva","family":"Mistry","sequence":"additional","affiliation":[{"name":"Department of Neurology and Rehabilitation Medicine, University of Cincinnati, OH (E.M., J.B., P.K.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2810-1685","authenticated-orcid":true,"given":"Thanh","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Department of Neurology, Boston Medical Center, MA (T.N.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0602-8509","authenticated-orcid":true,"given":"Sunil","family":"Sheth","sequence":"additional","affiliation":[{"name":"Department of Neurology, UT Health McGovern Medical School, Houston, TX 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P.K.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7786-5668","authenticated-orcid":true,"given":"Johanna","family":"Fifi","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY (A.M., D.G., J.F., J.M.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9141-2251","authenticated-orcid":true,"given":"Jeffrey L.","family":"Saver","sequence":"additional","affiliation":[{"name":"Department of Neurology, University of California, Los Angeles (J.L.S.)."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5489-2524","authenticated-orcid":true,"given":"J","family":"Mocco","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, NY (A.M., D.G., J.F., 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