Kawakami Shogo, Ishiyama Hiromichi, Satoh Takefumi, Tsumura Hideyasu, Sekiguchi Akane, Takenaka Kouji, Tabata Ken-Ichi, Iwamura Masatsugu, Hayakawa Kazushige
Department of Radiology and Radiation Oncology.
Department of Urology, Kitasato University School of Medicine, Kitasato, Sagamihara, Japan.
J Contemp Brachytherapy. 2017 Aug;9(4):316-322. doi: 10.5114/jcb.2017.69807. Epub 2017 Aug 30.
To compare prostate contours on conventional stepping transverse image acquisitions with those on twister-based sagittal image acquisitions.
Twenty prostate cancer patients who were planned to have permanent interstitial prostate brachytherapy were prospectively accrued. A transrectal ultrasonography probe was inserted, with the patient in lithotomy position. Transverse images were obtained with stepping movement of the transverse transducer. In the same patient, sagittal images were also obtained through rotation of the sagittal transducer using the "Twister" mode. The differences of prostate size among the two types of image acquisitions were compared. The relationships among the difference of the two types of image acquisitions, dose-volume histogram (DVH) parameters on the post-implant computed tomography (CT) analysis, as well as other factors were analyzed.
The sagittal image acquisitions showed a larger prostate size compared to the transverse image acquisitions especially in the anterior-posterior (AP) direction ( < 0.05). Interestingly, relative size of prostate apex in AP direction in sagittal image acquisitions compared to that in transverse image acquisitions was correlated to DVH parameters such as D ( = 0.518, = 0.019), and V ( = 0.598, = 0.005).
There were small but significant differences in the prostate contours between the transverse and the sagittal planning image acquisitions. Furthermore, our study suggested that the differences between the two types of image acquisitions might correlated to dosimetric results on CT analysis.
比较传统步进式横向图像采集与基于旋转模式的矢状面图像采集所得的前列腺轮廓。
前瞻性纳入20例计划接受永久性间质内前列腺近距离放疗的前列腺癌患者。患者取截石位，插入经直肠超声探头。通过横向探头的步进移动获取横向图像。在同一患者中，还使用“旋转”模式通过矢状面探头旋转获取矢状面图像。比较两种图像采集方式下前列腺大小的差异。分析两种图像采集方式的差异、植入后计算机断层扫描（CT）分析中的剂量体积直方图（DVH）参数以及其他因素之间的关系。
与横向图像采集相比，矢状面图像采集显示前列腺尺寸更大，尤其是在前后（AP）方向（<0.05）。有趣的是，矢状面图像采集中AP方向前列腺尖部的相对大小与横向图像采集中的相对大小与DVH参数如D（=0.518，=0.019）和V（=0.598，=0.005）相关。
横向和矢状面计划图像采集之间的前列腺轮廓存在微小但显著的差异。此外，我们的研究表明，两种图像采集方式之间的差异可能与CT分析中的剂量学结果相关。
