gms | German Medical Science

73. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Griechischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

29.05. - 01.06.2022, Köln

3D printed templates for intraoperative molding of patient specific cranioplastic implants – technique and clinical results

3D-Druckschablonen zur intraoperativen Herstellung von patientenspezifischen Kranioplastie Implantaten – Technik und klinische Ergebnisse

Meeting Abstract

  • presenting/speaker Johannes Pöppe - Uniklinikum Salzburg, Paracelsus Medizinische Privatuniversität, Universitätsklinik für Neurochirurgie, Salzburg, Österreich
  • Christoph Schwartz - Uniklinikum Salzburg, Paracelsus Medizinische Privatuniversität, Universitätsklinik für Neurochirurgie, Salzburg, Österreich
  • Mathias Spendel - Uniklinikum Salzburg, Paracelsus Medizinische Privatuniversität, Universitätsklinik für Neurochirurgie, Salzburg, Österreich
  • Peter A. Winkler - Uniklinikum Salzburg, Paracelsus Medizinische Privatuniversität, Universitätsklinik für Neurochirurgie, Salzburg, Österreich
  • Jörn Wittig - Uniklinikum Salzburg, Paracelsus Medizinische Privatuniversität, Universitätsklinik für Mund-Kiefer- und Gesichtschirurgie, Salzburg, Österreich
  • Christoph J. Griessenauer - Uniklinikum Salzburg, Paracelsus Medizinische Privatuniversität, Universitätsklinik für Neurochirurgie, Salzburg, Österreich

Deutsche Gesellschaft für Neurochirurgie. 73. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Griechischen Gesellschaft für Neurochirurgie. Köln, 29.05.-01.06.2022. Düsseldorf: German Medical Science GMS Publishing House; 2022. DocP202

doi: 10.3205/22dgnc518, urn:nbn:de:0183-22dgnc5180

Published: May 25, 2022

© 2022 Pöppe et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution 4.0 License. See license information at http://creativecommons.org/licenses/by/4.0/.


Outline

Text

Objective: In patients with large craniectomy defects and no autologous implant available manually molded Polymethylmethacrylate (PMMA) implants are feasible for cranioplasty. Even though those implants are readily available and cost-effective satisfying cosmetic results cannot always be achieved. In contrast, Computer Animated Design (CAD) implants are very costly but provide optimal reconstruction of the natural skull shape. Our aim was to develop and implement an in-house 3D printing workflow to provide patient specific templates for intraoperative molding of custom made PMMA cranial implants. Thus, combining the precision of CAD implants with the cost-effectiveness of manually molded PMMA implants. Here, we present our novel 3D design, printing and molding technique and a case series of our first 24 patients.

Methods: Pre- and post-craniectomy CT scans of patients with large skull defects were utilized to design two printable templates: a mold virtually obtained from the pre-craniectomy outer skull shape and a ring representing the craniectomy defect margins. Both templates were printed on a desktop 3D printer with biocompatible photopolymer resins. All used software applications and printing material was CE certified as medical products class I. PMMA implants were molded intraoperatively in a springform manner from the sterilized templates and directly implanted. Clinical and radiological data were retrospectively analyzed.

Results: 24 PMMA implants were performed on 28 consecutive patients. The median defect size was 86,1 cm2 (range 40,6-147,8 cm2). Median age was 46,5 (range 19-82) years, and median operating time was 83,5 (range 52-243) min. No intraoperative complications occurred; all implants fitted well into craniectomy defects. Excellent skull reconstruction could be confirmed in all postoperative CT scans. In four (16.7%) patients with distinct risk factors for postoperative hematoma, revision surgery for epidural hematoma had to be performed. No surgery-related mortality or new and permanent neurologic deficits were recorded.

Conclusion: A novel 3D printing workflow to provide templates for intraoperative molding of PMMA cranioplastic implants was developed and clinical implementation has been performed. Our “springform-technique” provides a feasible, cost-effective and easily adaptable alternative for cranioplastic surgery combining the precision and cosmetic advantages of computer-aided design (CAD) implants with the cost-effectiveness of manually molded PMMA implants.