学分布特点及适应症多野照射射野设计－学分布特点及适应症.ppt

chapter7 Treatment Planning and treatment performance Planning process overview Combine machine parameters and individual patient data to customize and optimize treatment Requires machine data, input of patient data, calculation algorithm Produces output of data in a form which can be used for treatment (the ‘treatment plan’) The main contents 外照射靶区剂量分布的规定 计划设计中的临床和生物学因素 临床剂量学原则 照射技术和射野设计原理 病人的定位与摆位 治疗计划的设计、评估与执行 Section1 外照射靶区剂量分布的规定 Volume definition is a prerequisite for meaningful 3D treatment planning and for accurate dose reporting. The ICRU 50 and 62 reports define and describe several target and critical structure volumes that aid in the treatment planning process and that provide a basis for comparison of treatment outcomes. 外照射靶区剂量分布的规定 Gross target volume (GTV) Clinical target volume (CTV) Planning target volume (PTV) Treatment volume Irradiation volume Maximum target dose 外照射靶区剂量分布的规定 Minimum target dose Mean target dose Hot spots Organ at risk Dose-volume histogram Gross Tumor Volume(GTV) The gross tumor volume is the gross palpable or visible demonstrable extent and location of malignant growth (ICRU 50) . Gross Tumor Volume (GTV) 肿瘤区指肿瘤的临床灶，为一般的诊断手段能够诊断出的可见的具有一定形状和大小的恶性病变的范围，包括转移的淋巴结和其它转移的病变（可认为是第二肿瘤区）。 当肿瘤已作根治术后则认为没有肿瘤区。 临床有两个原因要确定肿瘤区： 对根治性放疗，要给予肿瘤区以足够的剂量，使肿瘤得到控制 便于观察肿瘤随治疗剂量的变化及其它因素的影响 The GTV is usually based on information obtained from a combination of imaging modalities (CT, MRI, ultrasound, etc.), diagnostic modalities (pathology and histological reports, etc.) and clinical examination. Clinical Target Volume (CTV) “The clinical target volume (CTV) is the tissue volume that contains a demonstrable GTV and/or sub-clinical microscopic malignant disease, which has to be eliminated. This volume thus has to be treated adequately in order to achieve the aim of therapy, cure or palliation” (ICRU 50). Clinical Target Volume (CTV) The target volume consists of the demonstrated tumor, if present, and any other tissue with presumed tumor. This