滑膜树枝状脂肪瘤影像学表现

目的 探讨滑膜树枝状脂肪瘤(LA)的影像及其病理特征。方法 回顾性分析14例经手术病理证实为LA患者的影像及病理特征。对所有患者均行MR平扫,1例同时行MR增强扫描,3例行CT平扫,1例行数字X线摄影(DR)检查;均行病灶切除术,制做病理标本,并行HE染色。结果 MR平扫显示,14例滑囊积液,9例呈绒毛状或棕榈叶状,5例合并丘状和多丘状病灶;12例病灶主体附着于近骨面滑囊壁,2例附着于侧面囊壁;1例MR增强扫描示病灶表面线样强化。CT示2例膝关节髌上囊绒毛状或棕榈叶状低密度影;1例肩关节三角肌下囊绒毛状或棕榈叶状、丘状、并排多丘状低密度影,邻近肱骨骨质吸收。DR示1例膝关节髌上囊区密度增高。除滑囊积液外,仅2例无其他合并症。镜下显示,病变表面为正常(n=8)或轻度肥大(n=6)的滑膜细胞,中央区为大量成熟脂肪组织,伴扩张毛细血管、淋巴细胞和浆细胞浸润。结论 关节LA具有特征性影像及病理学表现,术前影像检查有助于正确诊断。

Imaging features of lipoma arborescens

Objective To explore the imaging and pathology features of lipoma arborescens (LA). Methods The imaging and pathology features of 14 patients with LA confirmed by surgery and pathology were retrospectively analyzed. All patients underwent MRI, of which 1 underwent contrast enhanced MRI, 3 underwent CT scanning, 1 underwent DR scanning. Resection surgery was performed in all patients, and specimen acquired were HE stained. Results All patients in conventional MRI demonstrated joint or bursa effusion, 9 cases revealed villous or frond-like lesions with narrow base, 5 cases also showed mound-like lesion with wide base, the main lesion attached to the bursa wall adjacent to the bone in 12 cases and adjacent to lateral wall in 2 cases, 1 case on enhanced MRI showed linear surface enhancement. In CT, 2 patients of knee joint revealed villous or frond-like low density in suprapatellar pouch, 1 patient of shoulder joint showed villous, frond-like or mound-like low density in subdeltoid bursa with erosion of adjacent bone. DR of the knee showed the increasing density of suprapatellar pouch. Only 2 cases had no complication except for bursa effusion. Microscopically, the lesion was covered by normal (n=8) or slightly hypertrophic (n=6) synovial cells, and the central zone had large amount of mature fat tissue, accompanying with dilated capillaries as well as lymphocyte and plasmocyte. Conclusion LA has specific imaging and pathological features, which is helpful for the diagnosis before surgery.