MIM软件CT图像自动刚性配准的准确性研究

Accuracy verification of automatic rigid registration of CT images with the MIM software

目的：验证分析放射治疗应用靶区勾画软件MIM的CT图像自动刚性配准的准确性。方法：利用西门子SOMATOM Definition AS CT扫描机对Penta-Guide模体进行扫描,获得的CT图像作为参考图像,再将模体相对于等中心沿左右、头脚和前后3个方向移动预定的距离,以及在冠状面旋转预定角度再平移,分别进行CT扫描;所获得的CT图像以DICOM格式传输至MIM6.5.4系统,与参考图像配准,分析左右、头脚和前后方向的平移配准误差以及冠状面旋转配准误差;选择头部肿瘤患者进行患者CT图像配准的验证。结果：Penta-Guide模体在左右、头脚和前后3个方向的配准误差均〈1 mm,冠状面旋转方向配准误差均〈0.5~o。头部疾病患者在左右、头脚和前后3个方向的配准误差也〈1 mm。结论：MIM软件CT图像自动刚性配准的准确性好,操作简单,可应用于临床。

Objective： To verify the accuracy of automatic rigid medical image registration with MIM 6.5.4 software newly used in radiotherapy. Methods： The Penta-Guide phantom was placed at isocenter and scanned with Siemens Definition AS CT scanner. CT images were obtained as reference images. Then the phantom was translated several given distances in lateral, longitudinal and vertical direction, and in three directions simultaneously, also with a translational and a rotational movement. All the CT images were transferred to MIM 6.5.4 system via DICOM. Translational and rotational errors were acquired by registering the floating images with the reference image. Patients with brain tumors were selected to perform patient-specific verification. Results： The PentaGuide phantom registration data showed that the translational errors were less than 1 mm in lateral, longitudinal or vertical directions, and the rotational errors in coronal plane were less than 0.5 degree. Registration errors for patients with brain tumor were less than 1 mm. Conclusion： Automatic rigid medical image registration using MIM software is accurate and can be safely used in clinical.