Department of Radiology/Division of Neuroradiology and Musculoskeletal Radiology, Medical University Vienna, Waehringerguertel 18-20, A-1090 Vienna, Austria.
Eur J Radiol. 2010 Feb;73(2):224-9. doi: 10.1016/j.ejrad.2008.11.003. Epub 2008 Dec 20.
To demonstrate the value of multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) in the preoperative assessment of orbital tumors, and to present, particularly, CT and MR image data fusion for surgical planning and performance in computer-assisted navigated surgery of orbital tumors.
In this retrospective case series, 10 patients with orbital tumors and associated complaints underwent MDCT and MRI of the orbit. MDCT was performed at high resolution, with a bone window level setting in the axial plane. MRI was performed with an axial 3D T1-weighted (w) gradient-echo (GE) contrast-enhanced sequence, in addition to a standard MRI protocol. First, MDCT and MR images were used to diagnose tumorous lesions compared to histology as a standard of reference. Then, the image data sets from CT and 3D T1-w GE sequences were merged on a workstation to create CT-MR fusion images that were used for interventional planning and intraoperative image guidance. The intraoperative accuracy of the navigation unit was measured, defined as the deviation between the same landmark in the navigation image and the patient. Furthermore, the clinical preoperative status was compared to the patients' postoperative outcome.
Radiological and histological diagnosis, which revealed 7 benign and 3 malignant tumors, were concordant in 7 of 10 cases (70%). The CT-MR fusion images supported the surgeon in the preoperative planning and improved the surgical performance. The mean intraoperative accuracy of the navigation unit was 1.35mm. Postoperatively, orbital complaints showed complete regression in 6 cases, were ameliorated notably in 3 cases, and remained unchanged in 1 case.
CT and MRI are essential for the preoperative assessment of orbital tumors. CT-MR image data fusion is an accurate tool for planning the correct surgical procedure, and can improve surgical results in computer-assisted navigated surgery of orbital tumors.
展示多层螺旋 CT（MDCT）和磁共振成像（MRI）在眼眶肿瘤术前评估中的价值，并特别介绍 CT 和 MR 图像数据融合在眼眶肿瘤计算机辅助导航手术中的应用，包括手术规划和执行。
在这项回顾性病例系列研究中，10 例眼眶肿瘤及相关症状患者接受了眼眶 MDCT 和 MRI 检查。MDCT 采用高分辨率进行，轴位骨窗水平设置。MRI 采用轴向 3D T1 加权（w）梯度回波（GE）增强序列，此外还采用标准 MRI 方案。首先，将 MDCT 和 MR 图像用于诊断肿瘤病变，并与组织学作为参考标准进行比较。然后，在工作站上将 CT 和 3D T1-w GE 序列的图像数据集合并，创建 CT-MR 融合图像，用于介入规划和术中图像引导。测量导航单元的术中准确性，定义为导航图像中相同标志点与患者之间的偏差。此外，还比较了术前临床状况与患者术后结果。
放射学和组织学诊断显示 10 例患者中有 7 例为良性肿瘤，3 例为恶性肿瘤，其中 7 例（70%）诊断结果与组织学相符。CT-MR 融合图像支持外科医生进行术前规划，并提高了手术效果。导航单元的平均术中准确性为 1.35mm。术后，6 例眼眶症状完全缓解，3 例明显改善，1 例无变化。
CT 和 MRI 是眼眶肿瘤术前评估的必要手段。CT-MR 图像数据融合是规划正确手术程序的准确工具，可以提高计算机辅助导航手术中眼眶肿瘤的手术效果。
