Early autologous cranioplasty: complications and identification of risk factors using virtual reality visualisation technique

Abstract

Background: Cranioplasty (CP) of autologous bone flap after decompressive craniectomy (DC) is known to be associated with a high complication rate, particularly bone flap resorption (BFR). In a retrospective study, we used a novel virtual reality (VR) visualisation technique to identify and evaluate risk factors associated with CP.

Method: Twenty-five patients underwent early autologous CP. All complications were recorded. Cranial computed tomography scans were visualised via the VR software to access the fitting accuracy of the bone flap (bone flap size, gap width at trepanation cutting edge, extent of osteoclastic extension).

Results: An overall complication rate of 44% was seen, and BFR was the most common (36%). Only ‘osteoclastic extension of trepanation’ (p = .04) was a significant risk factor for BFR. The factors ‘indication for DC’ (p = .09) and ‘size of bone flap’ (p = .09) had a tendency towards influencing the rate of BFR, while ‘age’ (p = .68), ‘time interval between DC and CP’ (p = 1.00), and ‘gap width’ (p = .50) were not considered to influence the BFR rate.

Conclusions: DC and subsequent CP is a complication-prone procedure. Therefore, it is relevant to identify and quantify probable risk factors for the most common complications, such as BFR. Here, we found that the extent of osteoclastic extension may impair the patient’s healing process. Our investigation was made considerably easier by using the novel VR visualisation technique, which allows parallax free measurements of distances in 3D space.

Keywords:

• 3D reconstruction
• acute brain swelling
• bone flap resorption
• decompressive craniectomy
• early autologous cranioplasty
• virtual reality visualisation

Acknowledgements

We thank Dr. Lidmila Fuskova for assistance with statistical analysis. The manuscript was proofread by Deborah Nock (Medical WriteAway, Norwich, UK).

Disclosure statement

All authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers' bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript.

Financial disclosure

The authors have no personal, financial, or institutional interests in any of the drugs, materials or devices described in this article.

Ethical approval

The authors state that this study has been approved by the ethics commission of the Medical Faculty, Witten/Herdecke University (Ref-Nr. 201/2018) and was performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki.

Informed consent

The ethics commission of the Medical Faculty, Witten/Herdecke University (Ref-Nr. 201/2018) confirmed that formal consent is not required for this retrospective study.

Animal experiments

This article does not contain any studies with animals performed by any of the authors.