超声图像与CBCT图像引导宫颈癌放疗摆位误差的对比分析

Comparative analysis of setup errors of ultrasound images and CBCT images in radiotherapy for cervical cancer

目的通过分析超声图像与锥体束CT(CBCT)图像引导宫颈癌的放疗摆位误差,验证超声图像引导在宫颈癌放疗中的实用性和可行性。方法选择2015年5月至2016年5月中科院合肥肿瘤医院收治的10例宫颈癌初治的患者,实施图像引导放疗(IGRT),每次放疗前分别行B超与CBCT验证,并分别记录每次前后、左右和头脚方向上移位的偏差。结果 B超验证后移位在左右方向、前后方向、头脚方向分别为(2.49±3.65)、(3.05±4.47)、(2.86±4.30)mm。CBCT验证后移位在左右方向、前后方向、头脚方向分别为(2.55±3.09)、(2.68±3.80)、(3.57±4.61)mm,比较2种方法在不同方向的摆位误差,差异均无统计学意义(P>0.05)。结论超声图像引导宫颈癌的放疗亦可应用于临床,其操作简便,无电离辐射、系统误差小、可实时纠正。

Objective To verify the practicability and feasibility of ultrasound guided radiotherapy for cervical cancer by analyzing the positioning errors of the CBCT image guided radiotherapy for cervical cancer. Methods Ten cases of cervical cancer patients were select-ed ,the implementation of image guided radiotherapy, before and after the daily radiotherapy was performed to verify the B ultrasound and CBCT, respectively, andthe deviation in direction of before and after, the left and right, the head and footwere recorded for each time. Results After B ultrasound examination, the center shift in the left and right direction, the front and back direction, the direction of the head was （2. 55 ±3. 09） mm,（2. 68 ± 3. 80） mm,（3. 57 ± 4. 61） mm, respectively. After the validation of CBCT, center shift in the left - right direction, and direction, the head foot direction was respectively （2. 49 ± 3. 65） mm, （3. 05 ±4. 47） mm, （2. 86 ±4. 30） mm, and the difference in the center shift of different directions was not statistically significant when the two methods were compared （P 〉0. 05）. Conclusion Ultrasound guided cervical cancer radiotherapy can be used in clinical practice, its operation being simple, without radiation and with slight system errorthat can be corrected in time.