CAJ | 학술논문

目的研究早期非小细胞肺癌(NSCLC)患者行立体定向放射治疗(SBRT)时,基于千伏级锥形束CT(kV-CBCT)和定位CT制定放疗计划的心脏受量的差异.方法选取在本院接受放射治疗的早期NSCLC患者15例,每次治疗前均拍摄CBCT进行摆位误差纠正.利用每位患者前10次的CBCT进行研究,处方剂量定义为5 Gy×10次.应用首次kV-CBCT与定位CT进行心脏范围勾画,比较两种勾画方式下心脏剂量学参数的差异.结果基于第1次治疗时的kV-CBCT图像勾画的心脏体积(717±103)cm3大于基于定位CT勾画的(588±90)cm3,差异具有统计学意义(t=13.8,P＜0.05);基于kV-CBCT获得的心脏相对剂量-体积(VxGy-R)指标中除V5Gy-R外,V10Gy-R、V15Gy-R、V20Gy.R、V25Gy-R、V30Gy-R、V35Gy-R大于基于定位CT,差异有统计学意义(t=2.3 ～3.9,P＜0.05);基于kV-CBCT所获得的绝对剂量-体积(VxGy-A)指标V5Gy-A、V10Gy-A、V15Gy-A、V20Gy-A、V25Gy-A、V30 Gy-A、V355 Gy-A大于基于定位CT,差异有统计学意义(t=4.8～7.9,P＜0.05);基于CBCT所获得的心脏固定体积内的剂量指标D50cm3、D100cm3、D150cm3、D200cm3、D250cm3及Dmean、Dmax大于基于定位CT,差异有统计学意义(t=2.9 ～6.5,P＜0.05).结论根据kV-CBCT的特性及其心脏受量统计分析,应用kV-CBCT进行心脏受量评价可弥补心跳和呼吸的影响,得到更真实、客观的剂量-体积参数.
목적 연구조기비소세포폐암(NSCLC)환자행입체정향방사치료(SBRT)시,기우천복급추형속CT(kV-CBCT)화정위CT제정방료계화적심장수량적차이.방법 선취재본원접수방사치료적조기NSCLC환자15례,매차치료전균박섭CBCT진행파위오차규정.이용매위환자전10차적CBCT진행연구,처방제량정의위5 Gy×10차.응용수차kV-CBCT여정위CT진행심장범위구화,비교량충구화방식하심장제량학삼수적차이.결과 기우제1차치료시적kV-CBCT도상구화적심장체적(717±103)cm3대우기우정위CT구화적(588±90)cm3,차이구유통계학의의(t=13.8,P＜0.05);기우kV-CBCT획득적심장상대제량-체적(VxGy-R)지표중제V5Gy-R외,V10Gy-R、V15Gy-R、V20Gy.R、V25Gy-R、V30Gy-R、V35Gy-R대우기우정위CT,차이유통계학의의(t=2.3 ～3.9,P＜0.05);기우kV-CBCT소획득적절대제량-체적(VxGy-A)지표V5Gy-A、V10Gy-A、V15Gy-A、V20Gy-A、V25Gy-A、V30 Gy-A、V355 Gy-A대우기우정위CT,차이유통계학의의(t=4.8～7.9,P＜0.05);기우CBCT소획득적심장고정체적내적제량지표D50cm3、D100cm3、D150cm3、D200cm3、D250cm3급Dmean、Dmax대우기우정위CT,차이유통계학의의(t=2.9 ～6.5,P＜0.05).결론 근거kV-CBCT적특성급기심장수량통계분석,응용kV-CBCT진행심장수량평개가미보심도화호흡적영향,득도경진실、객관적제량-체적삼수.
Objective To compare the difference in evaluating the heart irradiation dose based on different heart range contoured on kilovohage-cone beam computed tomography(kV-CBCT)and planning CT images in stereotactic body radiotherapy(SBRT)of non-small cell lung cancer(NSCLC)at early stage.Methods Fifteen early NSCLC patients who underwent radiotherapy were selected.For every case,kV-CBCT scan was achieved before every fraction treatment to correct the setup error,and the first 10 serious kV-CBCT images were adopted.The heart range on kV-CBCT and planning CT images was contoured and the differences between volume and dose-volume indices were analyzed.Results The heart volume on first kV-CBCT[(717 ± 103)cm3]was larger than that on planning CT[(588 ± 90)cm3]with statistical difference(t=13.8,P＜0.05).The relative dose-volume indices:V10Gy-R,V15Gy-R,V20Gy-R,V25Gy-R,V30Gy-R,V35Gy-R obtained on CBCT images were larger than those on planning CT with statistical difference(t=2.3-3.9,P＜0.05)expect for V5Gy-R.The absolute dose-volume indices:V5Gy-A,V10Gy-A,V15Gy-A,V20Gy-A,V25Gy-A,V30Gy-A,V35Gy.A obtained on CBCT images were larger than those on planning CT,and all differences were statistically significant(t=4.8-7.9,P＜0.05).The dose of certain heart volume Dmean,Dmax,D50 cm3,D100 cm3,D150 cm3,D200 cm3,D250 cm3,based on CBCT images were larger than CT images with statistical difference(t=2.9-6.5,P＜0.05).Conclusions Based on the characteristics of kV-CBCT and the dose-volume indices of heart,the more accurate and objective dose-volume indices could be obtained through applying kV-CBCT in SBRT of NSCLC.