Clinical Radiation Physics Service

我们已经制定了常规的动态调强放射治疗(DIMRT)。这是调强放射治疗中最复杂的治疗，需要大量的治疗前验证以确保准确实施。这些治疗是使用我们的双Clinac-21EX加速器提供的。高科技系统(TomoTreatment Inc.)用于通过螺旋断层疗法提供治疗的技术已经安装、接受，目前正在治疗患者。该系统为Rob提供了尖端的治疗技术，以支持未来的临床试验。我们已经开始使用我们的Nucletron高剂量率后加载机(HDR)，使用小而高强度的192Ir源进行组织间和腔间近距离放射治疗。我们的放射外科能力已经扩大，购买了3个直径分别为5 mm、7.5 mm和10 mm的新涂布器。一台新的飞利浦华晨16切片大口径CT模拟器已经接受了床铺控制升级。车载成像(OBI)已安装在较新的Clinac-21EX上。用于提供门控放射治疗的瓦里安RPM呼吸门控系统的最后一个组件已经获得，我们正在等待交付。呼吸门控将通过在治疗过程中补偿定期的呼吸运动来提高靶向能力。Radionics SRS头架系统已被改造为使用内部制造的特殊支架用于放射治疗单元。利用该系统已经开发了用于患者模拟和治疗计划的程序。最新的瓦里安加速器增加了星载成像功能。这提供了诊断质量的图像，这使得解剖和基准匹配更加准确。这对前列腺癌患者尤其有用。RapidArc治疗输送系统已经安装在较新的Clinac-21EX上，并与TomoTreatment Hi-ART单元提供了一定程度的冗余，并提供了其他独特的功能。这台机器上还安装了一种新的全碳纤维患者沙发套。这提高了千伏和中伏图像的质量，从而改善了目标区域的定位。它还允许复杂的处理技术，这在以前是不可能的，因为旧沙发顶部的钢支撑的衰减和分散。治疗计划系统已使用新的自适应计划软件进行了升级。一种新的体积质量保证体模已被采购并接受临床使用。该体模包含1386个以螺旋模式排列的二极管探测器，对于验证由TomoTreatment和RapidArc生成的复杂治疗场序列至关重要。它还提供软件，用于将探测器测量结果重新映射到患者图像集上，并将其与治疗计划等剂量体积进行比较。然后，它生成计划和测量的体积剂量分布的完整统计分析。我们已经获得了两个最先进的扫描水模，一个用于CT和断层治疗，另一个用于一般加速器。这将极大地便利为年度质量保证和研究目的而获取的数据。我们还批准了用新装置取代我们最旧的直线加速器的资金。

We have instituted routine dynamic Intensity Modulated Radiation Therapy (dIMRT). This is the most complex of IMRT treatments and requires considerable pre-treatment verification to ensure accurate execution. These treatments are delivered using our twin Clinac-21EX accelerators. A Hi-ART system (Tomotherapy Inc.) for delivering treatments via helical tomotherapy has been installed, accepted and is currently treating patients. This system provides ROB with cutting edge treatment technology to support future clinical trials. We have started a series of initiatives with our Nucletron High Dose-Rate Afterloader (HDR) , using a small, high intensity 192Ir source for interstitial and intercavitary brachytherapy. Our radiosurgery capability has been expanded with the acquisition of 3 new applicators with diameters of 5mm, 7.5mm and 10mm. A new Philips Brilliance 16 slice, large bore CT Simulator has received couch control upgrades. On-board imaging (OBI) has been installed on the newer Clinac-21EX. The final component of the Varian RPM Respiratory Gating system for providing gated radiation therapy has been acquired and we are awaiting delivery. Respiratory gating will improve targeting ability by compensating for regular respiratory motions during treatment.The Radionics SRS head frame system has been adapted to the Tomotherapy unit using a special support fabricated in-house. Procedures have been developed for patient simulation and treatment planning with this system. On-board imaging has been added to the newest Varian accelerator. This provides diagnostic quality images, which makes anatomical and fiducial matching much more accurate. This is especially useful for prostate patients. The RapidArc treatment delivery system has been installed on the newer Clinac-21EX and provides some degree of redundancy with the Tomotherapy Hi-ART unit as well as offering additional unique features. A new, all-carbon fiber patient couch top has also been installed on this machine. This improves the quality of both kV and MV images, resulting in improved localization of target areas. It also permits complex treatment techniques that had previously not been possible due to the attenuation and scatter of the steel supports of the old couch top. Treatment planning systems has been upgraded with the new adaptive planning software. A new volumetric Quality Assurance phantom has been procured and accepted for clinical use. This phantom contains 1386 diode detectors arranged in a helical pattern and is essential for the verification of complex treatment field sequences generated by both Tomotherapy and RapidArc. It also provides software for remapping the detector measurements onto patient image sets and compares them with treatment plan isodose volumes. It then generates a full statistical analysis of the planned versus measured volumetric dose distributions.We have acquired two state-of-the-art scanning water phantoms, one for CT and Tomotherapy and the second for general accelerator use. These should greatly facilitate data acquisition for annual quality assurance as well as for research purposes. We have also had funding approved for the replacement of our oldest linear accelerator with a new unit.