University of Oulu

Korhonen, T. K., Posti, J. P., Niinimäki, J., Serlo, W., Salokorpi, N., & Tetri, S. (2022). Two-center validation of the Oulu resorption score for bone flap resorption after autologous cranioplasty. Clinical Neurology and Neurosurgery, 212, 107083. https://doi.org/10.1016/j.clineuro.2021.107083

Two-center validation of the Oulu resorption score for bone flap resorption after autologous cranioplasty

Saved in:
Author: Korhonen, Tommi K.1,2; Posti, Jussi P.3; Niinimäki, Jaakko4;
Organizations: 1Research Unit of Clinical Neuroscience, Neurosurgery, University of Oulu, Oulu, Finland
2MRC Oulu Brain Health, University of Oulu, Oulu, Finland
3Neurocenter, Department of Neurosurgery and Turku Brain Injury Center, Turku University Hospital and University of Turku, Turku, Finland
4Department of Diagnostic Radiology and Research Unit of Medical Imaging, Physics and Technology, Oulu University Hospital and University of Oulu, Oulu, Finland
5PEDEGO Research Unit, MRC Oulu, University of Oulu, Oulu, Finland
6Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland
Format: article
Version: published version
Access: open
Online Access: PDF Full Text (PDF, 2.3 MB)
Persistent link: http://urn.fi/urn:nbn:fi-fe2022050332468
Language: English
Published: Elsevier, 2022
Publish Date: 2022-06-20
Description:

Abstract

Objective: Autologous bone has been the gold standard of cranioplasty materials for decades. Unique to autologous cranioplasty, bone flap resorption is a poorly understood and unclearly defined complication. Even further, it has been unclear, whether the resorption process eventually stabilizes over time. Thus, the sufficient follow-up period after autologous cranioplasty is unknown.

The Oulu Resorption Score (ORS) is a straight-forward classification system for the radiological interpretation of bone flap resorption. The aims of the present study were to evaluate the reliability of the ORS using intra-class correlation coefficient (ICC) and to assess the temporal progression of the resorption process.

Methods: We identified 108 consecutive autologous cranioplasty patients treated between 2005 and 2018 in two tertiary referral centers. All 365 head CT scans the patients had undergone were evaluated using the ORS in a blinded, independent two-center setting. Intra- and inter-observer reliabilities were calculated. The ORS was applied to study the temporal progression of the resorption process.

Results: The intra-observer reliability of the ORS was excellent (ICC 0.94, 95%CI 0.93–0.95). Inter-observer reliability was good-to-excellent (ICCs 0.87 and 0.89, 95%CIs 0.84–0.89 and 0.87–0.91, respectively). In scatterplot smoothing analyses, the progression of bone flap resorption appeared to stabilize 12–24 months after cranioplasty.

Conclusions: ORS is the only validated radiological tool for the standardized analysis of bone flap resorption after autologous cranioplasty. Evaluated using the ORS, the resorption process seemed to stabilize during the first two postoperative years after cranioplasty, suggesting that the sufficient follow-up time after autologous cranioplasty is two years.

see all

Series: Clinical neurology and neurosurgery
ISSN: 0303-8467
ISSN-E: 1872-6968
ISSN-L: 0303-8467
Volume: 212
Article number: 107083
DOI: 10.1016/j.clineuro.2021.107083
OADOI: https://oadoi.org/10.1016/j.clineuro.2021.107083
Type of Publication: A1 Journal article – refereed
Field of Science: 3126 Surgery, anesthesiology, intensive care, radiology
Subjects:
Funding: Finnish Medical Foundation – Grant #4268 (TKK), Academy of Finland – Grant #17379 (JPP), Government’s Special Financial Transfer tied to academic research in Health Sciences (Finland) (JPP), Maire Taponen Foundation – Grant (JPP).
Copyright information: © 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
  https://creativecommons.org/licenses/by/4.0/