四肢及脊柱浅筋膜中间筋膜层MRI特点及其对脂肪瘤屏障作用的临床观察

Clinical Observation and MRI imaging of the middle layer of superficial fascia and its natural barrier effect against the lipoma in Limbs and Spine

目的探讨四肢脊柱浅筋膜中间筋膜层对肿瘤的屏障作用。方法回顾117例共121部位(男48例,女69例)四肢脊柱脂肪瘤患者MRI、手术及病理结果,对肿瘤所在部位深筋膜、浅筋膜中间筋膜层的形态及肿瘤形态相关性进行观察。结果病人平均年龄52.2岁(15~82岁);脂肪瘤所在部位侧别:左侧44.4%(52例),右侧48.7%(57例),双侧5.1%(6例),中线1.7%(2例);部位:颈后部7.5%(9),胸背部5.8%(7),肩部23.1%(28),上臂15.7%(19),前臂7.4%(9),手3.3%(4),股部34.7%(42),小腿2.5%(3);肿瘤位置:肌内40.2%(47例),深筋膜深面17.9%(21例),浅筋膜中间筋膜深面23.9%(28例),浅筋膜中间筋膜浅面5.9%(7例),肌间隙11.9%(14例)。肿瘤形态:脂肪瘤均与正常组织存在边界,分叶状48.7%(57例),椭圆状41.9%(49例),扁平状9.4%(11例)。病理类型:棕色瘤3.4%(4例),血管脂肪瘤1.7%(2例),普通型86.3%(101例),纤维脂肪瘤8.4%(10例)。皮下脂肪瘤多位于深筋膜与中间筋膜层之间,呈分叶状,深筋膜深面及肌内肿瘤多为椭圆形,肿瘤形态与中间筋膜及深筋膜、肌外膜的形态相关。结论浅筋膜中间筋膜层是一层较致密的纤维结缔组织,位于深筋膜和皮肤之间,中间筋膜层对脂肪瘤增殖有一定的阻挡作用,是自然屏障结构,深筋膜和肌间隔同样是肿瘤屏障结构。

Objective To explore the barrier effect of the middle layer of superficial fascia against the proliferation of lipoma by MRI imaging and the observation of the growth pattern of the lipoma in the spine and extremities.Methods 117 lipoma cases(total 121 sites)(48 males,69 females)were collected in this retrospective study,all of which were treated with operation performed in Beijing Chao-yang Hospital.All the lesions were confirmed by the histopathologic results.The barrier role of the fascia at the site of the tumor was identified in operation and compared with the preoperative MRI.The deep fascia,superficial fascia,and the middle layer of superficial fascia were identified and the relationship between the lipoma with those structures were observed in operation and in MRI images.Results The average age of patient was 52.2(15-82)ys;52 case(44.4%)in left,57 cases(48.7%)in right,6 case(5.1%)in bilateral and 2 cases(1.7%)in midline;according the site of lipoma,there was 9(7.5%)in the neck,7(5.8%)in the upper back,28(23.1%)in the shoulder,19(15.7%)in the arm,9(7.4%)in the forearm,4(3.3%)in the hand,42(34.7%)in the thigh,3(2.5%)in the leg;according the position of lipoma,47cases(40.2%)was in the muscule,21 cases(17.9%)was under the deep fascia,28 cases(23.9%)between the deep fascia and the middle layer of the superficial fascia,7 cases(5.9%)between the skin and the middle layer of the superficial fascia,11 cases(9.4%)in the intermuscular space;57 cases(48.7%)was lobubar shape,49 cases(41.9%)more ellipticaland 11 cases(9.4%)flat according to the tumor shape,they are bordered with normal tissue and can be separated in operation;4 cases(3.4%)was hibernoma,2 cases(1.7%)angiolipoma,101 cases(86.3%)typical lipoma,10 cases(8.4%)fibrolipoma in the histopathologic classification.Conclusion The middle layer of superficial fascia was a mesh fascia that is widely located in spine and extremities.It plays an important role as a natural barrier against the proliferation of lipoma.It was also found that the deep fascia and muscle septum have a strong barrier and restrictive effects on tumors.