Su Yi, Davis Brian J, Furutani Keith M, Herman Michael G, Robb Richard A
Biomedical Imaging Resource, Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA.
Comput Aided Surg. 2007 Jan;12(1):25-34. doi: 10.3109/10929080601168239.
To develop and evaluate an integrated approach to intra-operative dosimetry for permanent prostate brachytherapy (PPB) by combining a fluoroscopy-based seed localization routine with a transrectal ultrasound (TRUS)-to-fluoroscopy fusion technique.
Three-dimensional seed coordinates are reconstructed based on the two-dimensional seed locations identified from three fluoroscopic images acquired at different angles. A seed-based registration approach was examined in both simulation and phantom studies to register the seed locations identified from the fluoroscopic images to the TRUS images. Dose parameters were then evaluated and compared to CT-based dosimetry from a patient dataset.
Less than 0.2% error in the D90 value was observed using the TRUS-fluoroscopy image-fusion-based method relative to the CT-based post-implantation dosimetry. In the phantom study, an average distance of 3 mm was observed between the seeds identified from TRUS and the reconstructed seeds at registration. Isodose contours were displayed superimposed on the TRUS images.
Promising results were observed in this preliminary study of a TRUS-fluoroscopy fusion-based brachytherapy dosimetry analysis method, suggesting that the method is highly sensitive and calculates clinically relevant dosimetry, including the prostate D90. Further validation of the method is required for eventual clinical application.
通过将基于荧光透视的籽源定位程序与经直肠超声（TRUS）-荧光透视融合技术相结合，开发并评估一种用于永久性前列腺近距离放射治疗（PPB）的术中剂量测定综合方法。
基于从不同角度获取的三张荧光透视图像所确定的二维籽源位置，重建三维籽源坐标。在模拟研究和体模研究中均检验了一种基于籽源的配准方法，以将从荧光透视图像中确定的籽源位置与TRUS图像配准。然后评估剂量参数，并与来自患者数据集的基于CT的剂量测定结果进行比较。
相对于基于CT的植入后剂量测定，使用基于TRUS-荧光透视图像融合的方法观察到D90值的误差小于0.2%。在体模研究中，配准时从TRUS识别出的籽源与重建的籽源之间的平均距离为3mm。等剂量线轮廓叠加显示在TRUS图像上。
在这项基于TRUS-荧光透视融合的近距离放射治疗剂量测定分析方法的初步研究中观察到了有前景的结果，表明该方法高度敏感，并且能够计算包括前列腺D90在内的临床相关剂量。该方法最终应用于临床还需要进一步验证。
