Amis E S
Department of Radiology, Columbia-Presbyterian Medical Center, New York, NY 10032.
AJR Am J Roentgenol. 1991 Aug;157(2):321-9. doi: 10.2214/ajr.157.2.1853816.
Retroperitoneal fibrosis is idiopathic in two thirds of cases and is found most commonly as an isolated fibrotic plaque centered over the lower lumbar spine and entrapping one or both ureters. It has been postulated that the fibrosis in the idiopathic cases results from a hypersensitivity reaction to antigens leaking into the retroperitoneum from atheromatous plaques in the aorta or common iliac arteries. In the remaining one third of cases, causes include ergot-derivative drugs, retroperitoneal hemorrhage or urine extravasation, and a desmoplastic response to a variety of tumors. In up to 15% of cases, associated fibrotic processes are found elsewhere in the body. Although the disease is imaged best with CT or MR, neither of these techniques can be used to differentiate benign from malignant plaques. Histologically, the disease is characterized in its early stages by inflammatory cells and edema in a loose collagen network. The mature plaque is composed of dense fibrous tissue with minimal cellular infiltration. This progression is important as it influences MR signal characteristics.
三分之二的病例中，腹膜后纤维化病因不明，最常见的表现是在下腰椎水平出现孤立的纤维化斑块，包绕一侧或双侧输尿管。据推测，特发性病例中的纤维化是由于对从主动脉或髂总动脉粥样斑块渗漏至腹膜后的抗原产生超敏反应所致。其余三分之一的病例病因包括麦角衍生物药物、腹膜后出血或尿液外渗，以及对多种肿瘤的促纤维增生反应。高达15%的病例在身体其他部位发现相关的纤维化病变。尽管CT或MR对该病的成像效果最佳，但这两种技术均无法用于鉴别良性和恶性斑块。在组织学上，疾病早期的特征是疏松胶原网络中有炎症细胞和水肿。成熟的斑块由致密纤维组织构成，细胞浸润极少。这种进展很重要，因为它会影响MR信号特征。
