{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,3]],"date-time":"2026-09-03T20:47:27Z","timestamp":1788468447084,"version":"build-2803163510"},"reference-count":42,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,10,9]],"date-time":"2022-10-09T00:00:00Z","timestamp":1665273600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon 2020 research and innovation program","award":["721766 (FBI)"],"award-info":[{"award-number":["721766 (FBI)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Background: Neurosurgical procedures are complex and require years of training and experience. Traditional training on human cadavers is expensive, requires facilities and planning, and raises ethical concerns. Therefore, the use of anthropomorphic phantoms could be an excellent substitute. The aim of the study was to design and develop a patient-specific 3D-skull and brain model with realistic CT-attenuation suitable for conventional and augmented reality (AR)-navigated neurosurgical simulations. Methods: The radiodensity of materials considered for the skull and brain phantoms were investigated using cone beam CT (CBCT) and compared to the radiodensities of the human skull and brain. The mechanical properties of the materials considered were tested in the laboratory and subsequently evaluated by clinically active neurosurgeons. Optimization of the phantom for the intended purposes was performed in a feedback cycle of tests and improvements. Results: The skull, including a complete representation of the nasal cavity and skull base, was 3D printed using polylactic acid with calcium carbonate. The brain was cast using a mixture of water and coolant, with 4 wt% polyvinyl alcohol and 0.1 wt% barium sulfate, in a mold obtained from segmentation of CBCT and T1 weighted MR images from a cadaver. The experiments revealed that the radiodensities of the skull and brain phantoms were 547 and 38 Hounsfield units (HU), as compared to real skull bone and brain tissues with values of around 1300 and 30 HU, respectively. As for the mechanical properties testing, the brain phantom exhibited a similar elasticity to real brain tissue. The phantom was subsequently evaluated by neurosurgeons in simulations of endonasal skull-base surgery, brain biopsies, and external ventricular drain (EVD) placement and found to fulfill the requirements of a surgical phantom. Conclusions: A realistic and CT-compatible anthropomorphic head phantom was designed and successfully used for simulated augmented reality-led neurosurgical procedures. The anatomic details of the skull base and brain were realistically reproduced. This phantom can easily be manufactured and used for surgical training at a low cost.<\/jats:p>","DOI":"10.3390\/bioengineering9100537","type":"journal-article","created":{"date-parts":[[2022,10,9]],"date-time":"2022-10-09T20:49:31Z","timestamp":1665348571000},"page":"537","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Development of a CT-Compatible, Anthropomorphic Skull and Brain Phantom for Neurosurgical Planning, Training, and Simulation"],"prefix":"10.3390","volume":"9","author":[{"given":"Marco","family":"Lai","sequence":"first","affiliation":[{"name":"Philips Research, High Tech Campus 34, 5656 Eindhoven, The Netherlands"},{"name":"Department of Engineering, Eindhoven University of Technology (TU\/e), 5612 Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Simon","family":"Skyrman","sequence":"additional","affiliation":[{"name":"Department of Clinical Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden"},{"name":"Department of Neurosurgery, Karolinska University Hospital, 17164 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Flip","family":"Kor","sequence":"additional","affiliation":[{"name":"Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Homan","sequence":"additional","affiliation":[{"name":"Philips Healthcare, 5684 Best, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9479-761X","authenticated-orcid":false,"given":"Victor Gabriel","family":"El-Hajj","sequence":"additional","affiliation":[{"name":"Department of Clinical Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden"},{"name":"Department of Neurosurgery, Karolinska University Hospital, 17164 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Drazenko","family":"Babic","sequence":"additional","affiliation":[{"name":"Philips Research, High Tech Campus 34, 5656 Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8781-1169","authenticated-orcid":false,"given":"Erik","family":"Edstr\u00f6m","sequence":"additional","affiliation":[{"name":"Department of Clinical Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden"},{"name":"Department of Neurosurgery, Karolinska University Hospital, 17164 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3776-6136","authenticated-orcid":false,"given":"Adrian","family":"Elmi-Terander","sequence":"additional","affiliation":[{"name":"Department of Clinical Neuroscience, Karolinska Institutet, 17177 Stockholm, Sweden"},{"name":"Department of Neurosurgery, Karolinska University Hospital, 17164 Stockholm, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Benno H. W.","family":"Hendriks","sequence":"additional","affiliation":[{"name":"Philips Research, High Tech Campus 34, 5656 Eindhoven, The Netherlands"},{"name":"Department of Biomechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter H. N.","family":"de With","sequence":"additional","affiliation":[{"name":"Department of Engineering, Eindhoven University of Technology (TU\/e), 5612 Eindhoven, The Netherlands"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"82","DOI":"10.3171\/2014.9.PEDS1447","article-title":"Design and evaluation of a new synthetic brain simulator for endoscopic third ventriculostomy","volume":"15","author":"Breimer","year":"2015","journal-title":"J. Neurosurg. 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