{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,13]],"date-time":"2026-04-13T16:07:01Z","timestamp":1776096421180,"version":"3.50.1"},"reference-count":34,"publisher":"Journal of Neurosurgery Publishing Group (JNSPG)","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,1,23]]},"abstract":"<jats:p>Craniopagus twins, particularly the total vertical type II variant, represent one of the rarest and most complex congenital malformations, with significant surgical challenges. This technical note presents the successful staged separation of craniopagus twins at 3 years 9 months of age, the oldest known to be separated to date. The twins shared a prominent circumferential venous sinus, requiring a novel surgical strategy. Advanced imaging, 3D modeling, and virtual reality planning in the metaverse\u2014between Brazil and the United Kingdom\u2014guided the 7 staged surgeries. Initially, partial separations focused on the more vulnerable twin. However, arteriographic evidence of venous dependency led to a paradigm shift, in which the authors performed the final stages on the other twin to preserve critical venous outflow. This innovative approach allowed division of the shared venous sinus without neurological compromise. The final separation, completed in 2 stages over 31 hours, resulted in successful independent circulations and recovery. This case highlights the importance of individualized surgical planning, collaborative international simulation, and the potential for adapting separation protocols based on venous architecture.<\/jats:p>","DOI":"10.3171\/2025.9.peds25330","type":"journal-article","created":{"date-parts":[[2026,1,24]],"date-time":"2026-01-24T02:09:29Z","timestamp":1769220569000},"page":"360-366","source":"Crossref","is-referenced-by-count":0,"title":["Circumferential venous sinus: an innovative separation method for total vertical type II craniopagus twins"],"prefix":"10.3171","volume":"37","author":[{"given":"Gabriel","family":"Mufarrej","sequence":"first","affiliation":[{"name":"Departments of Pediatric Neurosurgery,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gonzalo","family":"Castillo","sequence":"additional","affiliation":[{"name":"Departments of Pediatric Neurosurgery,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elias","family":"Tanus","sequence":"additional","affiliation":[{"name":"Neurosurgery,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nina","family":"Ventura Wilner","sequence":"additional","affiliation":[{"name":"Radiology,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jo\u00e3o Ricardo","family":"Penteado","sequence":"additional","affiliation":[{"name":"Departments of Pediatric Neurosurgery,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Maria Anna","family":"Brand\u00e3o","sequence":"additional","affiliation":[{"name":"Departments of Pediatric Neurosurgery,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fernanda Moraes Daniel","family":"Fialho","sequence":"additional","affiliation":[{"name":"Pediatrics,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sandro Miguel Souza","family":"de Lima","sequence":"additional","affiliation":[{"name":"Anesthesia,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mariana Tonon","family":"Rosa","sequence":"additional","affiliation":[{"name":"Anesthesia,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Clarice","family":"Abreu","sequence":"additional","affiliation":[{"name":"Cranio-Maxillofacial Surgery, and"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heron","family":"Werner","sequence":"additional","affiliation":[{"name":"Department of Radiology, DASA, Rio de Janeiro, Brazil; and"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Paulo","family":"Niemeyer Filho","sequence":"additional","affiliation":[{"name":"Neurosurgery,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vivaldo Moura","family":"Neto","sequence":"additional","affiliation":[{"name":"Cellular Biology, Instituto Estadual do C\u00e9rebro Paulo Niemeyer, Rio de Janeiro;"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noor ul Owase","family":"Jeelani","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Great Ormond Street Hospital, London, United Kingdom"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lu\u00eds Felipe","family":"Soares","sequence":"additional","affiliation":[{"name":"Pediatrics,"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1754","reference":[{"issue":"1","key":"b1","series-title":"Plast Reconstr Surg","first-page":"190","article-title":"Separation of craniopagus twins over the past 20 years: a systematic review of the variables that lead to successful separation","volume":"138","author":"Harvey DJ","year":"2016","unstructured":"Harvey DJ, Totonchi A, Gosain AK. Separation of craniopagus twins over the past 20 years: a systematic review of the variables that lead to successful separation. Plast Reconstr Surg. 2016;138(1):190\u2013200."},{"issue":"3","key":"b2","series-title":"Curr Opin Anaesthesiol","first-page":"381","article-title":"Conjoined twins in 2020: state of the art and future directions","volume":"33","author":"Frawley G","year":"2020","unstructured":"Frawley G. Conjoined twins in 2020: state of the art and future directions. Curr Opin Anaesthesiol. 2020;33(3):381\u2013387."},{"issue":"1","key":"b3","series-title":"Radiology","first-page":"18","article-title":"Multiparametric imaging for presurgical planning of craniopagus twins: the experience of two tertiary pediatric hospitals with six sets of twins","volume":"298","author":"Eley KA","year":"2021","unstructured":"Eley KA, Rossi-Espagnet MC, Schievano S,  Multiparametric imaging for presurgical planning of craniopagus twins: the experience of two tertiary pediatric hospitals with six sets of twins. Radiology. 2021;298(1):18\u201327."},{"issue":"3","key":"b4","series-title":"Clin Anat","first-page":"385","article-title":"Conjoined twins: from conception to separation, a review","volume":"30","author":"Mian A","year":"2017","unstructured":"Mian A, Gabra NI, Sharma T,  Conjoined twins: from conception to separation, a review. 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