Blomlie V, Lien H H, Iversen T, Winderen M, Tvera K
Department of Diagnostic Radiology, Norwegian Radium Hospital, Oslo, Norway.
Radiology. 1993 Jul;188(1):241-4. doi: 10.1148/radiology.188.1.8511304.
In patients with malignant pelvic tumors, radiation-induced insufficiency fractures of the sacrum may be mistaken for metastasis. Magnetic resonance (MR) imaging was performed in 18 patients with this condition, and the findings were studied retrospectively. The diagnosis was confirmed with at least one additional imaging modality in 16 patients, whereas the other two patients underwent clinical follow-up at 13 and 20 months without evidence of metastasis. In 17 patients, the lesions were consistent with edema and had diffuse low signal intensity on T1-weighted images and diffuse high signal intensity on short-inversion-time inversion-recovery images, thereby simulating metastasis. In one patient, bilateral sacral wing fractures were demonstrated directly as fairly well-defined linear zones. The alae sacri were involved in all patients; 16 patients had bilateral lesions. Awareness of this clinical entity and of the high sensitivity of MR imaging for demonstrating edema caused by the fracture should prevent confusion with metastatic disease and inappropriate treatment.
在恶性盆腔肿瘤患者中，放疗引起的骶骨应力性骨折可能被误诊为转移瘤。对18例患有这种情况的患者进行了磁共振（MR）成像，并对结果进行了回顾性研究。16例患者通过至少一种其他成像方式确诊，而另外两名患者分别在13个月和20个月时接受了临床随访，未发现转移证据。17例患者的病变表现为水肿，在T1加权图像上呈弥漫性低信号强度，在短反转时间反转恢复图像上呈弥漫性高信号强度，从而类似转移瘤。在一名患者中，双侧骶骨翼骨折直接表现为边界相当清晰的线性区域。所有患者的骶骨翼均受累；16例患者为双侧病变。认识到这种临床实体以及MR成像对显示骨折引起的水肿具有高敏感性，应可避免与转移性疾病混淆及不适当的治疗。
