{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T02:07:04Z","timestamp":1788228424685,"version":"build-2803163510"},"reference-count":23,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,5,3]],"date-time":"2026-05-03T00:00:00Z","timestamp":1777766400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Diagnostics"],"abstract":"<jats:p>Background\/Objectives: Mechanical thrombectomy (MT) enables direct examination of the retrieved thrombus in acute ischemic stroke. Thrombus composition may influence treatment outcomes and reflect underlying stroke mechanisms. This study aimed to analyze thrombus histological composition and CD34-positive endothelial cells and evaluate their association with clinical and radiological characteristics. Methods: Fifty-six patients with acute ischemic stroke who underwent MT were included. Thrombi were classified as fibrin-dominant or red blood cell (RBC)-dominant using hematoxylin\u2013eosin staining (H&amp;E). Endothelial cells were identified via CD34 immunostaining. Associations between thrombus composition, procedural variables, imaging findings, and clinical outcomes were analyzed. Results: Forty-one (73.2%) thrombi were fibrin-dominant, and 15 (26.8%) were RBC-dominant. Fibrin-dominant thrombi were significantly associated with more distal occlusions (p = 0.027) and with the use of stent-retrievers (p = 0.045). RBC-dominant thrombi were more frequently associated with the hyperdense artery sign (HAS) (p = 0.015). CD34-positive staining correlated with shorter symptom-to-door (p = 0.017) and symptom-to-puncture times (p &lt; 0.001). Endothelial ingrowth was more common in thrombi from proximal occlusions (p = 0.017). No significant associations were observed between thrombus composition and recanalization success, number of passes, or functional outcomes. The association between RBC-dominant thrombi and HAS supports the potential role of imaging markers in predicting thrombus composition prior to intervention. In addition, the presence and distribution of CD34-positive endothelial cells in relation to time intervals and occlusion location may reflect dynamic processes such as thrombus organization and vessel wall interaction. Conclusions: These findings highlight the heterogeneous nature of thrombus in acute ischemic stroke. Further studies are needed to clarify the biological and clinical implications of these observations.<\/jats:p>","DOI":"10.3390\/diagnostics16091390","type":"journal-article","created":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T00:15:02Z","timestamp":1777853702000},"page":"1390","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Histopathological Analysis of Thrombi in Acute Ischemic Stroke: An Exploratory Study of Thrombus Composition and CD34-Positive Endothelial Cells"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6095-7144","authenticated-orcid":false,"given":"Sena","family":"Aksoy","sequence":"first","affiliation":[{"name":"Department of Neurology, Bak\u0131rk\u00f6y Prof. Dr. Mazhar Osman Mental Health and Neurological Diseases Training and Research Hospital, University of Health Sciences, Istanbul 34147, Turkey"},{"name":"Department of Neurology, Faculty of Medicine, Istanbul Ayd\u0131n University, Istanbul 34295, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3222-874X","authenticated-orcid":false,"given":"Atay","family":"Vural","sequence":"additional","affiliation":[{"name":"Department of Neurology, Faculty of Medicine, Ko\u00e7 University, Istanbul 34010, Turkey"},{"name":"Research Center for Translational Medicine, Ko\u00e7 University, Istanbul 34010, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"\u0130brahim","family":"Kula\u00e7","sequence":"additional","affiliation":[{"name":"Department of Pathology, Faculty of Medicine, Ko\u00e7 University, Istanbul 34010, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hatem Hakan","family":"Sel\u00e7uk","sequence":"additional","affiliation":[{"name":"Department of Neuroradiology, Bak\u0131rk\u00f6y Dr. Sadi Konuk Training and Research Hospital, University of Health Sciences, Istanbul 34147, Turkey"},{"name":"Department of Neuroradiology, Ac\u0131badem Atasehir Hospital, Istanbul 34642, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ali Burak","family":"K\u0131z\u0131l\u0131rmak","sequence":"additional","affiliation":[{"name":"Research Center for Translational Medicine, Ko\u00e7 University, Istanbul 34010, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0860-8964","authenticated-orcid":false,"given":"Yasemin G\u00fcrsoy","family":"\u00d6zdemir","sequence":"additional","affiliation":[{"name":"Department of Neurology, Faculty of Medicine, Ko\u00e7 University, Istanbul 34010, Turkey"},{"name":"Research Center for Translational Medicine, Ko\u00e7 University, Istanbul 34010, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2674-6535","authenticated-orcid":false,"given":"Bayram","family":"Y\u0131lmaz","sequence":"additional","affiliation":[{"name":"Department of Physiology, Faculty of Medicine, Yeditepe University, Istanbul 34755, Turkey"},{"name":"Department of Physiology, Faculty of Medicine, Dokuz Eyl\u00fcl University, Izmir 35340, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"467","DOI":"10.1177\/1747493019884527","article-title":"Histological stroke clot analysis after thrombectomy: Technical aspects and recommendations","volume":"15","author":"Staessens","year":"2020","journal-title":"Int. J. Stroke"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"529","DOI":"10.1136\/neurintsurg-2016-012391","article-title":"Correlation of imaging and histopathology of thrombi in acute ischemic stroke with etiology and outcome: A systematic review","volume":"9","author":"Brinjikji","year":"2017","journal-title":"J. Neurointerv. Surg."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"650","DOI":"10.3174\/ajnr.A6467","article-title":"Is histologic thrombus composition in acute stroke linked to stroke etiology or to interventional parameters?","volume":"41","author":"Goebel","year":"2020","journal-title":"AJNR Am. J. Neuroradiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3035","DOI":"10.1161\/STROKEAHA.116.015228","article-title":"Histopathologic analysis of retrieved thrombi associated with successful reperfusion after acute stroke thrombectomy","volume":"47","author":"Hashimoto","year":"2016","journal-title":"Stroke"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1864","DOI":"10.1161\/STROKEAHA.116.013105","article-title":"Thrombus histology suggests cardioembolic cause in cryptogenic stroke","volume":"47","author":"Kleine","year":"2016","journal-title":"Stroke"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2206","DOI":"10.1161\/STROKEAHA.117.016590","article-title":"Ischemic stroke: What does the histological composition tell us about the origin of the thrombus?","volume":"48","author":"Sporns","year":"2017","journal-title":"Stroke"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Hassanpour, M., Amankeldi, A.S., Kobayashi, S., and Asahara, T. (2023). CD34 positive cells as endothelial progenitor cells in biology and medicine. Front. Cell Dev. Biol., 11.","DOI":"10.3389\/fcell.2023.1128134"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1016\/j.neurad.2014.01.124","article-title":"Thrombus composition in acute ischemic stroke: A histopathological study of thrombus extracted by endovascular retrieval","volume":"42","author":"Simons","year":"2015","journal-title":"J. Neuroradiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1007\/s00062-014-0347-x","article-title":"The impact of histological clot composition in embolic stroke","volume":"26","author":"Schubert","year":"2016","journal-title":"Clin. Neuroradiol."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Dargazanli, C., Rigau, V., Eker, O., Bareiro, C.R., Machi, P., Gascou, G., Arquizan, C., Ayrignac, X., Mourand, I., and Corlob\u00e9, A. (2016). High CD3+ cells in intracranial thrombi represent a biomarker of atherothrombotic stroke. PLoS ONE, 11.","DOI":"10.1371\/journal.pone.0154945"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"331","DOI":"10.1080\/09537104.2020.1748586","article-title":"Thrombus heterogeneity in ischemic stroke","volume":"32","author":"Staessens","year":"2021","journal-title":"Platelets"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1111","DOI":"10.1136\/neurintsurg-2020-016966","article-title":"Per-pass analysis of acute ischemic stroke clots: Impact of stroke etiology on extracted clot area and histological composition","volume":"13","author":"Fitzgerald","year":"2021","journal-title":"J. Neurointerv. Surg."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Cruts, J., Giezen, J., Gaalen, K., Beurskens, R., Ridwan, Y., Dijkshoorn, M.L., van Beusekom, H.M.M., Boodt, N., van der Lugt, A., and de Vries, J.J. (2023). The association between human blood clot analogue computed tomography imaging, composition, contraction and mechanical characteristics. PLoS ONE, 18.","DOI":"10.1371\/journal.pone.0293456"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2510","DOI":"10.1161\/STROKEAHA.120.033527","article-title":"Mechanical Characterization of Thrombi Retrieved with Endovascular Thrombectomy in Patients with Acute Ischemic Stroke","volume":"52","author":"Boodt","year":"2021","journal-title":"Stroke"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1131","DOI":"10.1161\/STROKEAHA.120.032810","article-title":"Thrombus Composition and Efficacy of Thrombolysis and Thrombectomy in Acute Ischemic Stroke","volume":"52","author":"Jolugbo","year":"2021","journal-title":"Stroke"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"243","DOI":"10.1161\/STROKEAHA.112.674127","article-title":"Density of thrombus on admission CT predicts revascularization efficacy in large vessel occlusion acute ischemic stroke","volume":"44","author":"Moftakhar","year":"2013","journal-title":"Stroke"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"40","DOI":"10.5853\/jos.2016.01522","article-title":"Computed tomography-based thrombus imaging fort he prediction of recanalization after reperfusion therapy in stroke","volume":"19","author":"Heo","year":"2017","journal-title":"J. Stroke"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"7811","DOI":"10.1007\/s00330-022-08762-y","article-title":"Quantitative thrombus characteristics on thin-slice computed tomography improve prediction of thrombus histopathology: Results of the MR CLEAN Registry","volume":"32","author":"Hund","year":"2022","journal-title":"Eur. Radiol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"748","DOI":"10.3390\/neurolint14040063","article-title":"Is composition of Brain Clot Retrieved by Mechanical Thrombectomy Associated with Stroke Aetiology and Clinical Outcomes in Acute Ischemic Stroke? A Systematic Review and Meta-analysis","volume":"14","author":"Huang","year":"2022","journal-title":"Neurol. Int."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1159\/000486042","article-title":"Erythrocyte-Rich Thrombus Is Associated with Reduced Number of Maneuvers and Procedure Time in Patients with Acute Ischemic Stroke Undergoing Mechanical Thrombectomy","volume":"8","author":"Maekawa","year":"2018","journal-title":"Cerebrovasc. Dis. Extra"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Shin, J.W., Jeong, H.S., Kwon, H., Song, K.S., and Kim, J. (2018). High red blood cell composition in clots is associated with successful recanalization during intra-arterial thrombectomy. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0197492"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"330","DOI":"10.1172\/JCI200420622","article-title":"Administration of CD34+ cells after stroke enhances neurogenesis via angiogenesis in a mouse model","volume":"114","author":"Taguchi","year":"2004","journal-title":"J. Clin. Investig."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1016\/j.brainres.2015.02.010","article-title":"Endothelial progenitor cells and revascularization following stroke","volume":"1623","author":"Ma","year":"2015","journal-title":"Brain Res."}],"container-title":["Diagnostics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/9\/1390\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T04:28:08Z","timestamp":1778560088000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2075-4418\/16\/9\/1390"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,3]]},"references-count":23,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2026,5]]}},"alternative-id":["diagnostics16091390"],"URL":"https:\/\/doi.org\/10.3390\/diagnostics16091390","relation":{},"ISSN":["2075-4418"],"issn-type":[{"value":"2075-4418","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,3]]}}}