Registrar, Department of Oral and Maxillofacial Surgery, Royal Brisbane and Women's Hospital, Brisbane, Australia.
Principal Research Fellow, School of Mechanical, Medical and Process Engineering, Faculty of Engineering, Queensland University of Technology; Jamieson Trauma Institute, Metro North Hospital and Health Service; Centre for Biomedical Technologies, Queensland University of Technology; ARC Training Centre for Multiscale 3D Imaging, Modelling, Manufacturing, Queensland University of Technology, Brisbane, Australia.
J Oral Maxillofac Surg. 2023 Sep;81(9):1116-1123. doi: 10.1016/j.joms.2023.05.015. Epub 2023 Jun 2.
Magnetic resonance imaging (MRI) is being increasingly considered as an alternative for the evaluation and reconstruction of orbital fractures. No previous research has compared the orbital volume of an MRI-imaged, three-dimensional (3D), reconstructed, and virtually restored bony orbit to the gold standard of computed tomography (CT).
To measure the orbital volumes generated from MRI-based 3D models of fractured bony orbits with virtually positioned prebent fan plates in situ and compare them to the volumes of CT-based virtually reconstructed orbital models.
This retrospective in-vitro study used CT and MRI data from adult patients with orbital trauma assessed at the Royal Brisbane and Women's Hospital Outpatient Maxillofacial Clinic from 2011 to 2012. Only those with orbital blowout fractures were included in the study.
The primary predictor variable was imaging modality, with CT- and MRI-based 3D models used for plate bending and placement.
The primary outcome variable was the orbital volume of the enclosed 3D models.
Additional data collected was age, sex, and side of fractured orbit. The effect of operator variability on plate contouring and orbital volume was quantified.
The Wilcoxon signed rank test was used to assess differences between orbital volumes with a significance level P < .05.
Of 11 eligible participants, six patients (four male and two female; mean age 31 ± 8.6 years) were enrolled. Two sets of six CT-based virtually restored orbits were smaller than the intact contralateral CT models by an average of 1.02 cm (95% CI -0.07 to 2.11 cm; P = .028) and 0.99 cm (95% CI 0.07 to 1.91 cm; P = .028), respectively. The average volume difference between the MRI-based virtually restored orbit and the intact contralateral MRI model was 0.97 cm (95% CI -1.08 to 1.94 cm; P = .75). Imaging modality did affect orbital volume difference for 1 set of CT and MRI models (0.63 cm; 95% CI -0.11 to 1.29 cm; P = .046) but not the other (0.69 cm; 95% CI -0.11 to 1.23 cm; P = .075). Single operator variability in plate bending did not result in significant (P = .75) volume differences.
MRI can be used to reconstruct orbital volume with a clinically acceptable level of accuracy.
磁共振成像（MRI）正越来越多地被认为是评估和重建眼眶骨折的替代方法。以前没有研究将 MRI 成像的三维（3D）重建和虚拟修复的骨眼眶容积与计算机断层扫描（CT）的金标准进行比较。
测量使用虚拟弯曲的预弯扇形板在原位的基于 MRI 的骨折骨眼眶 3D 模型生成的眼眶容积，并将其与基于 CT 的虚拟重建眼眶模型的容积进行比较。
这项回顾性的体外研究使用了 2011 年至 2012 年在昆士兰皇家妇女医院门诊颌面诊所评估的患有眼眶外伤的成年患者的 CT 和 MRI 数据。仅纳入那些有眼眶爆裂性骨折的患者。
主要预测变量是成像方式，CT 和 MRI 均用于板弯曲和放置。
主要观察结果是封闭 3D 模型的眼眶容积。
收集的其他数据是年龄、性别和骨折眼眶的侧别。量化了操作员变异性对板轮廓和眼眶容积的影响。
使用 Wilcoxon 符号秩检验评估眼眶容积的差异，显著性水平 P<.05。
在 11 名符合条件的参与者中，有 6 名患者（4 名男性和 2 名女性；平均年龄 31±8.6 岁）入选。两组基于 CT 的虚拟修复的眼眶比对侧 CT 模型小，平均分别小 1.02cm（95%CI-0.07 至 2.11cm；P=.028）和 0.99cm（95%CI0.07 至 1.91cm；P=.028）。基于 MRI 的虚拟修复眼眶与对侧 MRI 模型完整眼眶之间的平均体积差异为 0.97cm（95%CI-1.08 至 1.94cm；P=.75）。成像方式确实会影响一组 CT 和 MRI 模型的眼眶容积差异（0.63cm；95%CI-0.11 至 1.29cm；P=.046），但不会影响另一组（0.69cm；95%CI-0.11 至 1.23cm；P=.075）。单独操作员弯曲板的变异性并没有导致显著的（P=.75）体积差异。
MRI 可用于重建眼眶容积，具有临床可接受的准确度。
