Fondazione IRCCS Istituto Neurologico Carlo Besta, Health Department, Via Giovanni Celoria 11, 20133 Milan, Italy.
Centre for Medical Radiation Physics, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, Australia; Medical Imaging Department, College of Applied Medical Sciences, Aljouf University, Aljouf 72388, Saudi Arabia.
Phys Med. 2021 Sep;89:20-28. doi: 10.1016/j.ejmp.2021.07.010. Epub 2021 Jul 31.
In this work, the potential of an innovative "edgeless" silicon diode was evaluated as a response to the still unmet need of a reliable tool for plan dosimetry verification of very high dose, non-coplanar, patient-specific radiosurgery treatments. In order to prove the effectiveness of the proposed technology, we focused on radiosurgical treatments for functional disease like tremor or pain.
The edgeless diodes response has been validated with respect to clinical practice standard detectors by reproducing the reference dosimetry data adopted for the Treatment Planning System. In order to evaluate the potential for radiosurgery patient-specific treatment plan verification, the anthropomorphic phantom Alderson RANDO has been adopted along with three edgeless sensors, one placed in the centre of the Planning Target Volume, one superiorly and one inferiorly.
The reference dosimetry data obtained from the edgeless detectors are within 2.6% for output factor, off-axis ratio and well within 2% for tissue phantom ratio when compared to PTW 60,018 diode. The edgeless detectors measure a dose discrepancy of approximately 3.6% from the mean value calculated by the TPS. Larger discrepancies are obtained in very steep gradient dose regions when the sensors are placed outside the PTV.
The angular independent edgeless diode is proposed as an innovative dosimeter for patient quality assurance of brain functional disorders and other radiosurgery treatments. The comparison of the diode measurements with TPS calculations confirms that edgeless diodes are suitable candidates for patient-specific dosimetric verification in very high dose ranges delivered by non-isocentric stereotactic radiosurgery modalities.
在这项工作中，评估了一种创新的“无边缘”硅二极管的潜力，以满足对可靠工具的需求，该工具可用于验证非常高剂量、非共面、患者特异性立体定向放射外科治疗的计划剂量。为了证明所提出技术的有效性，我们专注于治疗功能疾病（如震颤或疼痛）的放射外科治疗。
通过再现用于治疗计划系统的参考剂量学数据，使无边缘二极管的响应相对于临床实践标准探测器得到验证。为了评估患者特异性放射外科治疗计划验证的潜力，采用了人体模型 Alderson RANDO 以及三个无边缘传感器，一个放置在计划靶区的中心，一个在上部，一个在下部。
与 PTW 60,018 二极管相比，从无边缘探测器获得的参考剂量学数据在输出因子方面的差异在 2.6%以内，在离轴比方面的差异在 2%以内，在组织体模比方面的差异在 2%以内。无边缘探测器测量的剂量与 TPS 计算的平均值相差约 3.6%。当传感器放置在 PTV 之外时，在非常陡峭的梯度剂量区域会获得更大的差异。
提出了角度独立的无边缘二极管作为一种创新的剂量计，用于脑功能障碍和其他放射外科治疗的患者质量保证。二极管测量值与 TPS 计算值的比较证实，无边缘二极管适用于通过非等中心立体定向放射外科模式提供的非常高剂量范围内的患者特异性剂量验证。
