Purpose

The purpose of this article is to present and evaluate a proposed rigid registration method in the application of real-time fusion of pre-operative 3DCT images and intraoperative 2DUS images.

Methods

A universal hybrid automatic rigid registration method was proposed, which allows registration of preoperative contrast enhanced CT with intraoperative 2D ultrasound images (neither CEUS nor 3DUS is required), with the possibility of manual correction. The method is based on automatically detectable markers, clearly identified in preoperative CT images, and by optical position tracking system during the procedure. A two-step fusion accuracy assessment was used. The first stage, the initial fusion assessment, was carried out at the time of the procedure. The second, objective stage (the final fusion assessment) was carried out after the procedure, and was based on the image and location data collected during the procedure. The clinical evaluation of the method was performed on 20 patients.

Results

For IFA and for Fusion Stability Assessment evaluation steps the following results were obtained, respectively: no fusion disorder: 10, good overlay: 8, permanently wrong fusion: 2 and no fusion disorders: 8, short-term fusion disorders: 9, frequent fusion disorders:3. The RMSE descriptive statistics (presenting order: median (first quartile third quartile) [min max]) was 8.87 (6.46 12.76) [5.04 18.84] mm.

Conclusion

The results are qualitatively comparable with results obtained in other independent research, quantitatively comparable in accuracy, achieving mostly better results in terms of preparation time consumed and operating in real time, which justifies the possible clinical usage of the proposed method.

中文翻译：

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基于刚性配准和支持经皮肝肿瘤消融的图像融合的初步临床评估

目的

本文的目的是提出和评估一种建议的刚性配准方法在术前3DCT图像和术中2DUS图像的实时融合中的应用。

方法

提出了一种通用的混合自动刚性套准方法，该方法允许术前对比增强的CT与术中2D超声图像（不需要CEUS或3DUS）进行套准，并且可以进行手动校正。该方法基于在手术前CT图像中清楚识别的自动可检测标记，并且在手术过程中采用光学位置跟踪系统。使用了两步融合精度评估。第一阶段，即最初的融合评估，是在手术时进行的。第二个客观阶段（最终融合评估）是在手术后进行的，并且是基于手术期间收集的图像和位置数据。该方法的临床评估在20例患者中进行。

结果

对于IFA和融合稳定性评估评估步骤，分别获得以下结果：无融合障碍：10，良好覆盖：8，永久错误融合：2和无融合障碍：8，短期融合障碍：9，频繁融合疾病：3。RMSE描述统计量（显示顺序：中位数（第一四分位数第三四分位数）[最小最大值]）为8.87（6.46 12.76）[5.04 18.84] mm。

结论

该结果与其他独立研究的结果在质量上可比，准确性在定量上可比，就消耗的制备时间和实时操作而言，大多可获得更好的结果，这证明了该方法可能的临床应用。