{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:37:57Z","timestamp":1760060277915,"version":"build-2065373602"},"reference-count":42,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2025,8,14]],"date-time":"2025-08-14T00:00:00Z","timestamp":1755129600000},"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: Digital subtraction angiography (DSA) remains the gold standard for assessing aneurysm morphology before and after treatment. While visual interpretation is common, quantitative image analysis remains underutilized in clinical practice. This study aimed to evaluate postoperative vascular changes in patients with middle cerebral artery (MCA) aneurysms using SymDIRECT-based pixel clustering on preoperative and postoperative DSA images. Methods: A total of 59 patients with unruptured MCA aneurysms were analyzed retrospectively. SymDIRECT clustering segmented angiographic images into four intensity clusters. Quantitative comparison of cluster pixel counts between pre- and postoperative images was performed. Results: Both neurosurgical clipping and endovascular treatment groups demonstrated significant reductions in medium- and high-intensity pixel clusters postoperatively, reflecting successful aneurysm occlusion. The background cluster increased post-treatment in most cases, with an average rise of over 14%, indicating effective anatomical exclusion of the aneurysm. Conclusions: SymDIRECT-based pixel clustering enables objective, pixel-level quantification of treatment response in DSA images. This approach may support standardized imaging follow-up protocols and improve reproducibility in neurovascular outcome assessment. Future integration with AI-based segmentation could facilitate real-time image interpretation.<\/jats:p>","DOI":"10.3390\/diagnostics15162036","type":"journal-article","created":{"date-parts":[[2025,8,14]],"date-time":"2025-08-14T14:51:46Z","timestamp":1755183106000},"page":"2036","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Quantitative DSA Analysis of MCA Aneurysms Using SymDIRECT Pixel Clustering: A Novel Framework for Objective Post-Treatment Evaluation"],"prefix":"10.3390","volume":"15","author":[{"given":"Ante","family":"Rotim","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Sestre Milosrdnice University Hospital Center, 10 000 Zagreb, Croatia"},{"name":"Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, 31 000 Osijek, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marina","family":"Ragu\u017e","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Dubrava University Hospital, 10 000 Zagreb, Croatia"},{"name":"School of Medicine, Catholic University of Croatia, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nikica","family":"Fulir","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Sestre Milosrdnice University Hospital Center, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3018-5248","authenticated-orcid":false,"given":"Darko","family":"Ore\u0161kovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Dubrava University Hospital, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1439-0930","authenticated-orcid":false,"given":"Vladimir","family":"Kalousek","sequence":"additional","affiliation":[{"name":"Department of Radiology, Sestre Milosrdnice University Hospital Center, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Petar","family":"Mar\u010dinkovi\u0107","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Dubrava University Hospital, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kre\u0161imir","family":"Rotim","sequence":"additional","affiliation":[{"name":"Special Hospital Neurospine, 10 000 Zagreb, Croatia"},{"name":"University of Applied Health Sciences, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4483-9364","authenticated-orcid":false,"given":"Bruno","family":"Splavski","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Dubrovnik General Hospital, 20 000 Dubrovnik, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silva","family":"Butkovi\u0107 Soldo","sequence":"additional","affiliation":[{"name":"Department of Neurology, University Hospital Center Osijek, 31 000 Osijek, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomislav","family":"Sajko","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Sestre Milosrdnice University Hospital Center, 10 000 Zagreb, Croatia"},{"name":"Faculty of Medicine, Josip Juraj Strossmayer University of Osijek, 31 000 Osijek, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,14]]},"reference":[{"key":"ref_1","first-page":"S53","article-title":"The supratentorial arteries","volume":"61","author":"Rhoton","year":"2007","journal-title":"Neurosurgery"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1398","DOI":"10.1161\/01.STR.0000073841.88563.E9","article-title":"Long-term angiographic recurrences after selective endovascular treatment of aneurysms","volume":"34","author":"Raymond","year":"2003","journal-title":"Stroke"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1016\/S0140-6736(03)13860-3","article-title":"Unruptured intracranial aneurysms: Natural history, clinical outcome, and risks of surgical and endovascular treatment","volume":"362","author":"Wiebers","year":"2003","journal-title":"Lancet"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1227\/01.NEU.0000097194.35781.EA","article-title":"Preliminary experience using the Neuroform stent for the treatment of cerebral aneurysms","volume":"54","author":"Fiorella","year":"2004","journal-title":"Neurosurgery"},{"key":"ref_5","unstructured":"Shishegar, R., Joshi, A., Tolcos, M.D., Walker, W., and Johnston, L. 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