Giandini Tommaso, Panaino Costanza M V, Avuzzi Barbara, Morlino Sara, Villa Sergio, Bedini Nice, Carabelli Gabriele, Frasca Sarah C, Romanyukha Anna, Rosenfeld Anatoly, Pignoli Emanuele, Valdagni Riccardo, Carrara Mauro
Medical Physics Unit, Department of Diagnostic Imaging and Radiotherapy, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
Prostate Program Unit, Scientific Directorate, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan - Italy.
Tumori. 2017 Mar 24;103(2):136-142. doi: 10.5301/tj.5000609. Epub 2017 Feb 11.
To validate and apply a method for the quantification of breathing-induced prostate motion (BIPM) for patients treated with radiotherapy and implanted with electromagnetic transponders for prostate localization and tracking.
For the analysis of electromagnetic transponder signal, dedicated software was developed and validated with a programmable breathing simulator phantom. The software was then applied to 1,132 radiotherapy fractions of 30 patients treated in supine position, and to a further 61 fractions of 2 patients treated in prone position.
Application of the software in phantom demonstrated reliability of the developed method in determining simulated breathing frequencies and amplitudes. For supine patients, the in vivo analysis of BIPM resulted in median (maximum) amplitudes of 0.10 mm (0.35 mm), 0.24 mm (0.66 mm), and 0.17 mm (0.61 mm) in the left-right (LR), cranio-caudal (CC), and anterior-posterior (AP) directions, respectively. Breathing frequency ranged between 7.73 and 29.43 breaths per minute. For prone patients, the ranges of the BIPM amplitudes were 0.1-0.5 mm, 0.5-1.3 mm, and 0.7-1.7 mm in the LR, CC, and AP directions, respectively.
The developed method was able to detect the BIPM with sub-millimeter accuracy. While for patients treated in supine position the BIPM represents a reduced source of treatment uncertainty, for patients treated in prone position, it can be higher than 3 mm.
验证并应用一种用于量化呼吸诱导前列腺运动（BIPM）的方法，该方法适用于接受放射治疗并植入电磁应答器以进行前列腺定位和跟踪的患者。
为了分析电磁应答器信号，开发了专用软件，并使用可编程呼吸模拟器模型进行了验证。然后将该软件应用于30例仰卧位治疗患者的1132个放射治疗分次，以及2例俯卧位治疗患者的另外61个分次。
该软件在模型中的应用证明了所开发方法在确定模拟呼吸频率和幅度方面的可靠性。对于仰卧位患者，BIPM的体内分析结果显示，左右（LR）、头脚（CC）和前后（AP）方向的中位（最大）幅度分别为0.10毫米（0.35毫米）、0.24毫米（0.66毫米）和0.17毫米（0.61毫米）。呼吸频率在每分钟7.73至29.43次呼吸之间。对于俯卧位患者，BIPM幅度在LR、CC和AP方向上的范围分别为0.1 - 0.5毫米、0.5 - 1.3毫米和0.7 - 1.7毫米。
所开发的方法能够以亚毫米精度检测BIPM。虽然对于仰卧位治疗的患者，BIPM是治疗不确定性的一个较小来源，但对于俯卧位治疗的患者，它可能高于3毫米。
