{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,8]],"date-time":"2025-12-08T22:36:43Z","timestamp":1765233403729,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,9,6]],"date-time":"2022-09-06T00:00:00Z","timestamp":1662422400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Tomography"],"abstract":"<jats:p>(1) Background: The normal A1 segment of the anterior cerebral artery (ACA) has a supraoptic course. The proximal infraoptic course of an A1 segment leaving the internal carotid artery (ICA) near the origin of the ophthalmic artery is a rare possibility. This study aimed to determine the prevalence and detailed anatomy of infraoptic A1 segments. (2) Methods: We retrospectively studied 145 computed tomography angiograms from 92 male and 53 female cases, with ages varying from 61 to 78 y.o. (3) Results: In 21\/145 cases, infraoptic or infrachiasmatic horizontal-medial courses of A1 segments that emerged distally from the ICA were found. Distal infraoptic A1 segments were bilateral in 16\/145 cases and unilateral in 3\/145 cases. Infrachiasmatic A1 segments were found bilaterally in 2\/145 male cases. All the infraoptic\/infrachiasmatic A1 segments left long ICAs with low bifurcations. In 7\/34 sides with distal infraoptic or infrachiasmatic A1 segments, supracarotid courses were present. In one female, the right A1 segment had an anterior supraclinoid, supracarotid and infraoptic course. In two female cases with a bilateral distal infraoptic A1, the segment was almost contacting the respective posterior cerebral artery. (4) Conclusions: In cases with dolicho(ectatic) ICAs, the A1 segments could have infraoptic and supracarotid courses the neurosurgeons should be aware of.<\/jats:p>","DOI":"10.3390\/tomography8050188","type":"journal-article","created":{"date-parts":[[2022,9,8]],"date-time":"2022-09-08T09:51:09Z","timestamp":1662630669000},"page":"2243-2255","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["The Infraoptic or Infrachiasmatic Course of the Anterior Cerebral Artery Emerging an Elongated Internal Carotid Artery"],"prefix":"10.3390","volume":"8","author":[{"given":"Drago\u015f Ionu\u0163","family":"Minc\u0103","sequence":"first","affiliation":[{"name":"Division of Anatomy, Department 1, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, RO-020021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8723-0540","authenticated-orcid":false,"given":"Mugurel Constantin","family":"Rusu","sequence":"additional","affiliation":[{"name":"Division of Anatomy, Department 1, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, RO-020021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Petrinel Mugurel","family":"R\u0103doi","sequence":"additional","affiliation":[{"name":"Division of Neurosurgery, Department 6\u2014Clinical Neurosciences, Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, RO-020021 Bucharest, Romania"},{"name":"Clinic of Neurosurgery, \u201cDr. Bagdasar-Arseni\u201d Emergency Clinical Hospital, RO-041915 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alexandra Diana","family":"Vrapciu","sequence":"additional","affiliation":[{"name":"Division of Anatomy, Department 1, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, RO-020021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4130-9402","authenticated-orcid":false,"given":"Sorin","family":"Hostiuc","sequence":"additional","affiliation":[{"name":"Department of Legal Medicine and Bioethics, Faculty of Dental Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, RO-020021 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Corneliu","family":"Toader","sequence":"additional","affiliation":[{"name":"Division of Neurosurgery, Department 6\u2014Clinical Neurosciences, Faculty of Medicine, \u201cCarol Davila\u201d University of Medicine and Pharmacy, RO-020021 Bucharest, Romania"},{"name":"Clinic of Neurosurgery, \u201cDr. Bagdasar-Arseni\u201d Emergency Clinical Hospital, RO-041915 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,6]]},"reference":[{"key":"ref_1","unstructured":"Osborn, A.G. (1999). Diagnostic Cerebral Angiography, Lippincott Williams & Wilkins. [2nd ed.]."},{"key":"ref_2","unstructured":"Gray, H., Standring, S., Anand, N., Birch, R., Collins, P., Crossman, A., Gleeson, M., Jawaheer, G., Smith, A.L., and Spratt, J.D. (2016). Gray\u2019s Anatomy: The Anatomical Basis of Clinical Practice, Elsevier. [41 ed.]."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"959","DOI":"10.47162\/RJME.61.3.38","article-title":"The discovery of the circle of Willis as a result of using the scientific method in anatomical dissection","volume":"61","author":"Dumitrescu","year":"2020","journal-title":"Rom. J. Morphol. Embryol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"71","DOI":"10.3340\/jkns.2010.47.1.71","article-title":"Infraoptic course of both anterior cerebral arteries","volume":"47","author":"Ji","year":"2010","journal-title":"J. Korean Neurosurg. Soc."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"368","DOI":"10.7461\/jcen.2014.16.4.368","article-title":"An unruptured anterior communicating artery aneurysm with bilateral infraoptic anterior cerebral arteries. Case report and review of the literature","volume":"16","author":"Chua","year":"2014","journal-title":"J. Cereb. Endovasc. Neurosurg."},{"key":"ref_6","first-page":"452","article-title":"Recognition and importance of an infraoptic anterior cerebral artery: Case report","volume":"23","author":"Given","year":"2002","journal-title":"AJNR Am. J. Neuroradiol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1177\/159101990601200210","article-title":"Bilateral infraoptic origin of anterior cerebral arteries: A rare anomaly and its embryological and clinical significance","volume":"12","author":"Chakraborty","year":"2006","journal-title":"Interv. Neuroradiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"950","DOI":"10.3171\/jns.1991.75.6.0950","article-title":"Surgically verified variations in the A1 segment of the anterior cerebral artery. Report of two cases","volume":"75","author":"Maurer","year":"1991","journal-title":"J. Neurosurg."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1895","DOI":"10.1007\/s00276-021-02812-8","article-title":"True terminal pentafurcation of the external carotid artery and terminal trifurcation of the contralateral one, occipitoauricular trunk, retropharyngeal internal carotid artery","volume":"43","author":"Moraru","year":"2021","journal-title":"Surg. Radiol. Anat."},{"key":"ref_10","unstructured":"(2022, August 15). Horos Project 2018 DICOM Image Viewing and Measuring. Available online: http:\/\/horosproject.org\/."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"927","DOI":"10.4103\/ajns.AJNS_34_19","article-title":"Surgical Significance of Infra-Optic Course of A1 Segment of Anterior Cerebral Artery: Report of Two Cases","volume":"14","author":"Nandish","year":"2019","journal-title":"Asian J. Neurosurg."},{"key":"ref_12","first-page":"131","article-title":"An unusual human anterior cerebral artery","volume":"93","author":"Robinson","year":"1959","journal-title":"J. Anat."},{"key":"ref_13","first-page":"1315","article-title":"Infraoptic course of the anterior cerebral artery associated with an anterior communicating artery aneurysm: Anatomic case report and embryological considerations","volume":"44","author":"Spinnato","year":"1999","journal-title":"Neurosurgery"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"237","DOI":"10.7461\/jcen.2012.14.3.237","article-title":"A Ruptured Aneurysm at the Infraoptic Azygous Anterior Cerebral Artery with the Contralateral Internal Carotid Artery Agenesis Treated by Y-stent Assisted Coil Embolization","volume":"14","author":"Kang","year":"2012","journal-title":"J. Cereb. Endovasc. Neurosurg."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.clinimag.2021.03.014","article-title":"Infraoptic anterior cerebral artery or carotid-anterior cerebral artery anastomosis: A very rare embryological variation. Case series and review of literature","volume":"79","author":"Kochar","year":"2021","journal-title":"Clin. Imaging"},{"key":"ref_16","first-page":"345","article-title":"Unusual anomaly of anterior cerebral artery","volume":"9","author":"Isherwood","year":"1969","journal-title":"Acta. Radiol. Diagn. (Stockh.)"},{"key":"ref_17","first-page":"71","article-title":"Anomalie rare du polygone de Willis: Trajet sous-optique des deux art\u00e8res c\u00e9r\u00e9brales ant\u00e9rieures. An\u00e9vrysme associ\u00e9 de la bifurcation du tronc basilaire","volume":"26","author":"Besson","year":"1980","journal-title":"Neurochirurgie"},{"key":"ref_18","first-page":"243","article-title":"Rare abnormalities of the circle of Willis: Infra-optic pathway of the anterior cerebral arteries (author\u2019s transl)","volume":"26","author":"Lehmann","year":"1980","journal-title":"Neurochirurgie"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1087","DOI":"10.1007\/s00701-008-0016-4","article-title":"Infraoptic anterior cerebral artery: Review, report of two cases and an anatomical classification","volume":"150","author":"Wong","year":"2008","journal-title":"Acta. Neurochir. (Wien.)"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"797","DOI":"10.4103\/0028-3886.166563","article-title":"Infraoptic course of the anterior cerebral artery associated with anterior communicating artery and distal anterior cerebral artery aneurysms","volume":"63","author":"Rao","year":"2015","journal-title":"Neurol India"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"12","DOI":"10.2176\/nmccrj.2013-0351","article-title":"Dissecting Aneurysm at the Proximal Segment of the Anterior Cerebral Artery Associated with Infraoptic Course Anterior Cerebral Artery","volume":"1","author":"Kawaji","year":"2014","journal-title":"NMC Case Rep. J."},{"key":"ref_22","first-page":"871","article-title":"A case showing the infraoptic course of the anterior cerebral artery associated with anterior cerebral artery aneurysm","volume":"19","author":"Takeshita","year":"1991","journal-title":"No Shinkei Geka"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"887","DOI":"10.1007\/s00276-016-1651-8","article-title":"Infraoptic anterior cerebral artery: Case series report and literature review","volume":"38","author":"Kim","year":"2016","journal-title":"Surg. Radiol. Anat."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"247","DOI":"10.4103\/ajns.AJNS_193_19","article-title":"Infraoptic Course of Anterior Cerebral Artery Coexistence with Double Fenestration of Proximal A2 Segment of Anterior Cerebral Artery with Associated Dysplastic Anterior Communicating Artery Aneurysm Treated with Stent-Assisted Coiling","volume":"15","author":"Mahajan","year":"2020","journal-title":"Asian J. Neurosurg."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1016\/j.clineuro.2010.12.009","article-title":"Anterior communicating artery aneurysm associated with an infraoptic course of anterior cerebral artery and rare variant of the persistent trigeminal artery: A case report and literature review","volume":"113","author":"Turkoglu","year":"2011","journal-title":"Clin. Neurol. Neurosurg."},{"key":"ref_26","first-page":"525","article-title":"A case of bilateral infraoptic course of ACA associated with multiple cerebral artery aneurysms","volume":"26","author":"Ogura","year":"1998","journal-title":"No Shinkei Geka"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1007\/s00276-019-02353-1","article-title":"Carotid-anterior cerebral artery (ACA) anastomosis associated with azygos ACA and ophthalmic artery arising from the middle meningeal artery: A case report","volume":"42","author":"Matsuura","year":"2020","journal-title":"Surg. Radiol. Anat."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"378","DOI":"10.3171\/jns.1976.44.3.0378","article-title":"Carotid-anterior cerebral artery anastomosis. Case report","volume":"44","author":"Nutik","year":"1976","journal-title":"J. Neurosurg."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"654","DOI":"10.1227\/00006123-198811000-00021","article-title":"Carotid-anterior cerebral artery anastomosis with aneurysm: Case report and review of the literature","volume":"23","author":"Odake","year":"1988","journal-title":"Neurosurgery"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1007\/s00234-011-0847-1","article-title":"Carotid-anterior cerebral artery anastomosis on MR angiography: A university hospital-based study","volume":"54","author":"Uchino","year":"2012","journal-title":"Neuroradiology"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/S0899-7071(03)00154-2","article-title":"Carotid-anterior cerebral artery anastomosis: MR angiographic features and literature review","volume":"28","author":"Uchino","year":"2004","journal-title":"Clin. Imaging"},{"key":"ref_32","first-page":"1071","article-title":"Three cases of carotid anterior cerebral anastomosis","volume":"18","author":"Ban","year":"1990","journal-title":"No Shinkei Geka"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"689.e1","DOI":"10.1016\/j.wneu.2015.11.021","article-title":"Carotid-Anterior Cerebral Artery Anastomosis Associated with Paraclinoid Aneurysm and Ophthalmic Artery Originating From Middle Meningeal Artery: Case Report and Consideration of Terminology","volume":"88","author":"Yi","year":"2016","journal-title":"World Neurosurg."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"937","DOI":"10.1007\/s00276-016-1805-8","article-title":"Infraoptic anterior cerebral artery (ACA) versus carotid-ACA anastomosis","volume":"39","author":"Uchino","year":"2017","journal-title":"Surg. Radiol. Anat."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"588","DOI":"10.1212\/WNL.12.9.588","article-title":"Agenesis of the internal carotid artery","volume":"12","author":"Turnbull","year":"1962","journal-title":"Neurology"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1007\/BF01401101","article-title":"Infra-optic course of anterior cerebral artery and low bifurcation of the internal carotid artery","volume":"38","author":"Bosma","year":"1977","journal-title":"Acta. Neurochir. (Wien.)"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"717","DOI":"10.3171\/jns.1977.46.6.0717","article-title":"Transsphenoidal decompression of the optic nerve and chiasm. Visual results in 62 patients","volume":"46","author":"Laws","year":"1977","journal-title":"J. Neurosurg."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1046\/j.1442-9071.2001.00367.x","article-title":"Carotid artery ectasia coexistent with primary open angle glaucoma","volume":"29","author":"Ellis","year":"2001","journal-title":"Clin. Exp. Ophthalmol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1016\/j.wneu.2022.04.038","article-title":"Anatomical Triangles for Use in Skull Base Surgery: A Comprehensive Review","volume":"164","author":"Hendricks","year":"2022","journal-title":"World Neurosurg."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"e41","DOI":"10.1016\/j.wneu.2020.04.048","article-title":"An Eyebrow, Supracarotid Triangle Approach for Lesions at the Ventral Thalamopeduncular Junction: A Technical Report","volume":"140","author":"Briggs","year":"2020","journal-title":"World Neurosurg."},{"key":"ref_41","first-page":"ons86","article-title":"The supracarotid-infrafrontal approach: Surgical technique and clinical application to cavernous malformations in the anteroinferior Basal Ganglia","volume":"64","author":"Waldron","year":"2009","journal-title":"Neurosurgery"}],"container-title":["Tomography"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2379-139X\/8\/5\/188\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T00:23:57Z","timestamp":1760142237000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2379-139X\/8\/5\/188"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,9,6]]},"references-count":41,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2022,10]]}},"alternative-id":["tomography8050188"],"URL":"https:\/\/doi.org\/10.3390\/tomography8050188","relation":{},"ISSN":["2379-139X"],"issn-type":[{"type":"electronic","value":"2379-139X"}],"subject":[],"published":{"date-parts":[[2022,9,6]]}}}