Institute of Medical Physics, School of Physics, University of Sydney, NSW 2006, Australia.
Phys Med Biol. 2013 Sep 7;58(17):5983-96. doi: 10.1088/0031-9155/58/17/5983. Epub 2013 Aug 12.
Kilovoltage intratreatment monitoring (KIM) is a novel real-time localization modality where the tumor position is continuously measured during intensity modulated radiation therapy (IMRT) or intensity modulated arc therapy (IMAT) by a kilovoltage (kV) x-ray imager. Adding kV imaging during therapy adds radiation dose. The additional effective dose is quantified for prostate radiotherapy and compared to dose from other localization modalities. The software PCXMC 2.0 was used to calculate the effective dose delivered to a phantom as a function of imager angle and field size for a Varian On-Board Imager. The average angular effective dose was calculated for a field size of 6 cm × 6 cm. The average angular effective dose was used in calculations for different treatment scenarios. Treatment scenarios considered were treatment type and fractionation. For all treatment scenarios, (i.e. conventionally fractionated and stereotactic body radiotherapy (SBRT), IMRT and IMAT), the total KIM dose at 1 Hz ranged from 2-10 mSv. This imaging dose is less than the Navotek radioactive implant dose (64 mSv) and a standard SBRT cone beam computed tomography pretreatment scan dose (22 mSv) over an entire treatment regime. KIM delivers an acceptably low effective dose for daily use as a real-time image-guidance method for prostate radiotherapy.
千伏级术中监测（KIM）是一种新型的实时定位方式，通过千伏级（kV）X 射线成像仪在调强放疗（IMRT）或调强弧形治疗（IMAT）期间连续测量肿瘤位置。在治疗过程中增加千伏级成像会增加辐射剂量。对前列腺放疗的额外有效剂量进行了量化，并与其他定位方式的剂量进行了比较。使用 PCXMC 2.0 软件计算了 Varian On-Board Imager 作为成像角度和射野大小函数的体模的有效剂量。计算了 6cm×6cm 射野大小的平均角度有效剂量。平均角度有效剂量用于不同治疗方案的计算。考虑的治疗方案包括治疗类型和分割。对于所有治疗方案（即常规分割和立体定向体部放疗（SBRT）、调强放疗和调强弧形治疗），1Hz 时的总 KIM 剂量范围为 2-10mSv。与整个治疗期间的 Navotek 放射性植入物剂量（64mSv）和标准 SBRT 锥形束计算机断层扫描预处理扫描剂量（22mSv）相比，这种成像剂量较低。KIM 作为前列腺放疗的实时图像引导方法，每天的有效剂量可接受。
