Lung cancer is one of the most common malignant tumors. It has the highest incidence and mortality rate of all cancers worldwide. Late diagnosis of nonsmall cell lung cancer(NSCLC) is very common in clinical practice,...Lung cancer is one of the most common malignant tumors. It has the highest incidence and mortality rate of all cancers worldwide. Late diagnosis of nonsmall cell lung cancer(NSCLC) is very common in clinical practice, and most patients miss the chance for radical surgery. Thus, radiotherapy plays an indispensable role in the treatment of NSCLC. Radiotherapy technology has evolved from the classic two-dimensional approach to three-dimensional conformal and intensity-modulated radiotherapy. However, how to ensure delivery of an accurate dose to the tumor while minimizing the irradiation of normal tissues remains a huge challenge for radiation oncologists, especially due to the positioning error between fractions and the autonomous movement of organs. In recent years, image-guided radiotherapy(IGRT) has greatly increased the accuracy of tumor irradiation while reducing the irradiation dose delivered to healthy tissues and organs. This paper presents a brief review of the definition of IGRT and the various technologies and applications of IGRT. IGRT can help ensure accurate dosing of the target area and reduce radiation damage to the surrounding normal tissue. IGRT may increase the local control rate of tumors and reduce the incidence of radio-therapeutic complications.展开更多
目的:研究头颅模体在不同CT扫描条件下模拟定位图像对射波刀(CK)G4系统六维颅骨追踪(6D-skull)技术相同图像引导条件下头部体位系统误差的影响。方法:使用头颅模体(Lucy)模拟患者,将CT的X射线管不同管电压分为80 k V组、100 k V组、120 ...目的:研究头颅模体在不同CT扫描条件下模拟定位图像对射波刀(CK)G4系统六维颅骨追踪(6D-skull)技术相同图像引导条件下头部体位系统误差的影响。方法:使用头颅模体(Lucy)模拟患者,将CT的X射线管不同管电压分为80 k V组、100 k V组、120 k V组及140 k V组,在不同管电压、相同管电流(440 m As)下,模体相同扫描层厚1 mm,分别获取CT模拟定位(CT-sim)图像。通过Multi Plan计划系统分别生成相应的两幅正交定位数字重建图像(DRR)。将头颅模体置于治疗床面,按照CT-sim中心点摆位,采用CK图像引导系统的两个正交X射线管同时曝光与分别曝光方式,且曝光参数相同,记录每组、每种曝光方式各采集100份的3个线性方向(X轴、Y轴和Z轴)和3个旋转方向(L-R旋转、UP-DOWN旋转和CW-CCW旋转)6个方向的体位误差数据。根据公式M=2.5∑+0.7δ计算X轴、Y轴和Z轴3个线性方向的外扩边界。结果:每种图像引导曝光方式相同方向头部体位误差数据各组之间差异均有统计学意义(F=39.133,F=235.431,F=234.349,F=31.638,F=289.814,F=515.825;P<0.01)。两种曝光方式不同管电压组头部体位误差数据以120 kV组头部体位误差绝对值数据分析中的标准差较小,头部体位误差较稳定。计算两种曝光方式,不同管电压条件下3个线性方向中各类头部体位误差数据外放范围最大值为0.402 mm,最小值为0.009 mm,95%置信区间(95%CI)为0.17~0.27 mm。结论:CT不同X射线管电压条件模拟定位图像,对相同条件图像引导产生的头部体位系统误差是有一定影响。在电压120 k V,440 m As下的模拟定位图像对CK-G4系统图像引导放射治疗(IGRT)头部体位系统误差影响较小、系统误差的稳定性好,可提高CK-G4系统立体定向放射治疗图像引导的精准度。展开更多
目的:应用千伏级锥形束CT (kV级CBCT)图像引导放疗技术评估肝癌患者分次放疗间位置的变化。方法15例肝癌患者,每例患者在放疗前行CBCT扫描,每周1~3次,共获取121幅 CBCT图像。离线下以肝脏、椎体外轮廓分别为参照物完成CBCT图像...目的:应用千伏级锥形束CT (kV级CBCT)图像引导放疗技术评估肝癌患者分次放疗间位置的变化。方法15例肝癌患者,每例患者在放疗前行CBCT扫描,每周1~3次,共获取121幅 CBCT图像。离线下以肝脏、椎体外轮廓分别为参照物完成CBCT图像与计划CT的配准,将配准结果定义为分次放疗间肝脏及椎体位置的变化,将两者配准结果的差值定义为肝脏相对于椎体位置的变化,分别予以评估。结果分次放疗间在三维方向,肝脏位移的绝对值以上下方向最大6.3 mm (0~19.3 mm)、左右方向次之2.3 mm(0~16.0 mm)、前后方向最小1.5 mm (0~7.6 mm)(P<0.001);椎体位移的绝对值以上下方向最大6.0 mm (0~18.0 mm)、左右方向次之3.0 mm (0~16.0 mm)、前后方向最小2.0 mm (0~10.0 mm)(P<0.05);肝脏相对于椎体位移的绝对值以上下方向最大4.8 mm (0.1~19.3 mm)、左右方向次之2.0 mm (0~8.6 mm)、上下方向最小1.4 mm (0~10.3 mm)(P<0.001)。若通过配准椎体校正患者位置,放疗时左右、上下、前后方向肝脏位移的绝对值可能增大,可能性分别为39.7%、42.1%、43.0%。结论椎体不适于作为肝癌图像引导放疗的参照物。展开更多
文摘Lung cancer is one of the most common malignant tumors. It has the highest incidence and mortality rate of all cancers worldwide. Late diagnosis of nonsmall cell lung cancer(NSCLC) is very common in clinical practice, and most patients miss the chance for radical surgery. Thus, radiotherapy plays an indispensable role in the treatment of NSCLC. Radiotherapy technology has evolved from the classic two-dimensional approach to three-dimensional conformal and intensity-modulated radiotherapy. However, how to ensure delivery of an accurate dose to the tumor while minimizing the irradiation of normal tissues remains a huge challenge for radiation oncologists, especially due to the positioning error between fractions and the autonomous movement of organs. In recent years, image-guided radiotherapy(IGRT) has greatly increased the accuracy of tumor irradiation while reducing the irradiation dose delivered to healthy tissues and organs. This paper presents a brief review of the definition of IGRT and the various technologies and applications of IGRT. IGRT can help ensure accurate dosing of the target area and reduce radiation damage to the surrounding normal tissue. IGRT may increase the local control rate of tumors and reduce the incidence of radio-therapeutic complications.
文摘目的:研究头颅模体在不同CT扫描条件下模拟定位图像对射波刀(CK)G4系统六维颅骨追踪(6D-skull)技术相同图像引导条件下头部体位系统误差的影响。方法:使用头颅模体(Lucy)模拟患者,将CT的X射线管不同管电压分为80 k V组、100 k V组、120 k V组及140 k V组,在不同管电压、相同管电流(440 m As)下,模体相同扫描层厚1 mm,分别获取CT模拟定位(CT-sim)图像。通过Multi Plan计划系统分别生成相应的两幅正交定位数字重建图像(DRR)。将头颅模体置于治疗床面,按照CT-sim中心点摆位,采用CK图像引导系统的两个正交X射线管同时曝光与分别曝光方式,且曝光参数相同,记录每组、每种曝光方式各采集100份的3个线性方向(X轴、Y轴和Z轴)和3个旋转方向(L-R旋转、UP-DOWN旋转和CW-CCW旋转)6个方向的体位误差数据。根据公式M=2.5∑+0.7δ计算X轴、Y轴和Z轴3个线性方向的外扩边界。结果:每种图像引导曝光方式相同方向头部体位误差数据各组之间差异均有统计学意义(F=39.133,F=235.431,F=234.349,F=31.638,F=289.814,F=515.825;P<0.01)。两种曝光方式不同管电压组头部体位误差数据以120 kV组头部体位误差绝对值数据分析中的标准差较小,头部体位误差较稳定。计算两种曝光方式,不同管电压条件下3个线性方向中各类头部体位误差数据外放范围最大值为0.402 mm,最小值为0.009 mm,95%置信区间(95%CI)为0.17~0.27 mm。结论:CT不同X射线管电压条件模拟定位图像,对相同条件图像引导产生的头部体位系统误差是有一定影响。在电压120 k V,440 m As下的模拟定位图像对CK-G4系统图像引导放射治疗(IGRT)头部体位系统误差影响较小、系统误差的稳定性好,可提高CK-G4系统立体定向放射治疗图像引导的精准度。
文摘目的:应用千伏级锥形束CT (kV级CBCT)图像引导放疗技术评估肝癌患者分次放疗间位置的变化。方法15例肝癌患者,每例患者在放疗前行CBCT扫描,每周1~3次,共获取121幅 CBCT图像。离线下以肝脏、椎体外轮廓分别为参照物完成CBCT图像与计划CT的配准,将配准结果定义为分次放疗间肝脏及椎体位置的变化,将两者配准结果的差值定义为肝脏相对于椎体位置的变化,分别予以评估。结果分次放疗间在三维方向,肝脏位移的绝对值以上下方向最大6.3 mm (0~19.3 mm)、左右方向次之2.3 mm(0~16.0 mm)、前后方向最小1.5 mm (0~7.6 mm)(P<0.001);椎体位移的绝对值以上下方向最大6.0 mm (0~18.0 mm)、左右方向次之3.0 mm (0~16.0 mm)、前后方向最小2.0 mm (0~10.0 mm)(P<0.05);肝脏相对于椎体位移的绝对值以上下方向最大4.8 mm (0.1~19.3 mm)、左右方向次之2.0 mm (0~8.6 mm)、上下方向最小1.4 mm (0~10.3 mm)(P<0.001)。若通过配准椎体校正患者位置,放疗时左右、上下、前后方向肝脏位移的绝对值可能增大,可能性分别为39.7%、42.1%、43.0%。结论椎体不适于作为肝癌图像引导放疗的参照物。