磁共振观察宫颈癌放疗后盆部骨髓变化

目的分析宫颈癌放疗中与放疗后盆部骨髓MR改变。探讨MR成像对显示盆部骨髓损伤的临床价值。方法48例经病理证实的宫颈癌患者在放射治疗前及治疗中和治疗后不同时间段行盆腔的轴位SE T1WI，轴位及矢状位TSE T2WI，冠状位SPIR，以及Gd—DTPA增强后T1WI SE的轴位、冠状位、矢状位扫描。在MR图像上观察盆部骨髓在放疗前后的信号改变。结果骨髓信号最早出现改变是在外照射开始后第8天，患者受照剂量在12Gy时。放疗早期，骨髓在T1WI，T2WI及SPIR序列上信号升高，T1WI增强扫描见强化。放疗晚期，骨髓的T1WI，T2WI信号升高程度增加，SPIR序列出现信号降低，T1WI增强扫描，骨髓强化不明显。53％的患者在T1WI、T2WI上，18％的患者在SPIR序列上见照射野外骨髓信号有改变。结论宫颈癌外照射放疗可引起照射野内、外骨髓多种MR信号改变，并有一定规律性，对宫颈癌临床治疗有指导意义。

Effect of radiation therapy on pelvis bone-marrow in patients with cervical cancer: evaluation with MR imaging

Objective To present the radiation-induced changes of bone marrow in patients with cervical cancer at magnetic resonance (MR) imaging during and after radiation therapy (RT) and to investigate the clinical value of MR imaging in demonstration of the irradiated bone marrow of pelvis. Methods Pelvic MR imaging was performed in 48 patients with cervical carcinoma before, during, and after radiation therapy. The MR scanning included axial SE T1WI, axial and sagittal TSE T2WI, coronal SPIR, and axial, sagittal and coronal Gd-DTPA enhanced T1WI SE. The changes of pelvic bone marrow in signal were observed at MR images. Results Radiation-induced changes in MR signal intensity (SI) were detected as early as 8 days after the initiation of external beam radiotherapy (EBRT) when the radiation dose was 12 Gy. Acute changes of bone marrow SI in MR can be demonstrated as increased SI on T1-weighted, T2-weighted and SPIR images, and enhanced SI on contrasted T1-weighted images. During the chronic phase of RT, SI of bone marrow showed steady and marked increase on T1-weighted and T2-weighted images, and decrease on SPIR sequence in some patients, and no enhanced SI on contrasted T1-weighted. 53% patients were shown SI changes on T1-weighted and T2-weighted images, and 18% patients were shown SI changes on SPIR images in bone marrow outside the RT field. Conclusion Various SI changes of bone marrow can be detected on different MR images during and after RT, which may be valuable in designing treatment schedules for cervical carcinoma.