在肝脏立体定向放射治疗(SBRT)中,精确的图像引导至关重要,作为这种治疗方法的基础。SBRT在肝癌治疗中的准确性在很大程度上依赖于细致的成像技术。隔膜,位于肝脏附近,是一个重要的解剖结构,易受位置和运动变化的影响,这可能会影响肝脏肿瘤靶向的准确性。这项研究探讨了实时千伏投影图像(KVPSI)与数字重建X射线照相术(DRR)相比在屏气肝肿瘤SBRT期间评估隔膜位置偏差的应用。一名被诊断为胆管癌的76岁男性使用分裂弧体积调节弧治疗(VMAT)进行了屏气SBRT,一个完整的弧被分成六个子弧,每个跨越60度。在治疗期间通过KVPSI连续监测隔膜圆顶位置。计算并分析了每个分裂弧的膜片的反向位置偏差。病例报告显示,整个弧中的平均隔膜圆顶偏差为0.47mm(标准偏差:4.47mm)。这项开创性的研究展示了在屏气肝肿瘤VMAT-SBRT期间使用实时KVPSI进行动态隔膜位置变化评估的可行性。整合实时成像技术增强了我们对屏气变化的理解,从而指导适应性治疗策略,并有可能改善治疗结果。通过进一步研究进行临床验证至关重要。
In liver stereotactic body radiotherapy (SBRT), precise image guidance is paramount, serving as the foundation of this treatment approach. The accuracy of SBRT in liver cancer treatment heavily relies on meticulous imaging techniques. The diaphragm, situated adjacent to the liver, is a crucial anatomical structure susceptible to positional and motion variations, which can potentially impact the accuracy of liver tumor targeting. This study explores the application of real-time kilovoltage projection streaming images (KVPSI) in comparison to digitally reconstructed radiography (DRR) for assessing diaphragm position deviations during breath-hold liver tumor SBRT. A 76-year-old male diagnosed with cholangiocarcinoma underwent breath-hold SBRT using split arc volumetric modulated arc therapy (VMAT), where a full arc was split into six sub-arcs, each spanning 60 degrees. The diaphragm dome positions were continuously monitored through KVPSI during treatment. The intrafractional position deviations of the diaphragm were calculated and analyzed for each split arc. The
case report revealed a mean diaphragm dome deviation of 0.47 mm (standard deviation: 4.47 mm) in the entire arc. This pioneering study showcases the feasibility of intrafractional diaphragm position variation assessment using real-time KVPSI during the breath-hold liver tumor VMAT-SBRT. Integrating real-time imaging techniques enhances our comprehension of the intra-breath-hold variations, thereby guiding adaptive treatment strategies and potentially improving treatment outcomes. Clinical validation through further research is essential.