Watanabe M, Sugimura K, Kuroda S, Okizuka H, Ishida T
Department of Radiology, Shimane Medical University, Izumo, Japan.
Clin Imaging. 1995 Jul-Sep;19(3):182-7. doi: 10.1016/0899-7071(94)00050-m.
Postirradiation changes in the rectum and perirectal tissue were assessed by computed tomography (CT) in 55 patients (total of 60 examinations) and correlated with radiation dose and time elapsed. Thickening of the perirectal fascia, increased density of the perirectal fat, and swelling of the rectal wall occurred in 48, 60, and 8% of patients, respectively, regardless of radiation dose within 30 Gy. However, widening of the presacral space was seen in 8% of patients receiving a rectal dose of less than 45 Gy, a percentage that increased to 16% for patients receiving 45 Gy or more. Thickening of the perirectal fascia, increased density of the perirectal fat, widening of the presacral space, and muscular changes were seen regardless of the time from the start of therapy. CT does not appear to be reliable enough in detecting residual or recurrent tumor in the rectum. However, knowledge of the CT features of postirradiation changes is helpful for diagnosis in patients with pelvic malignancies.
通过计算机断层扫描（CT）对55例患者（共60次检查）的直肠及直肠周围组织的放疗后变化进行评估，并与放射剂量和时间进行关联。无论放射剂量是否在30 Gy以内，分别有48%、60%和8%的患者出现直肠周围筋膜增厚、直肠周围脂肪密度增加和直肠壁肿胀。然而，直肠剂量小于45 Gy的患者中8%出现骶前间隙增宽，接受45 Gy或更高剂量的患者这一比例增至16%。无论从治疗开始后的时间如何，均可观察到直肠周围筋膜增厚、直肠周围脂肪密度增加、骶前间隙增宽及肌肉变化。CT在检测直肠残留或复发性肿瘤方面似乎不够可靠。然而，了解放疗后变化的CT特征有助于盆腔恶性肿瘤患者的诊断。
