髁突骨软骨瘤与髁突增生患者的CT表现特点分析

目的:比较下颌骨髁突骨软骨瘤和单侧下颌骨髁突增生的CT表现特点。方法:对2005—2010年上海交通大学医学院附属第九人民医院口腔颌面外科收治的下颌骨髁突骨软骨瘤11例和单侧下颌骨髁突增生8例患者的CT影像学资料进行评价,评价指标包括病变髁突大小、病变范围以及病变周围软硬组织改变。结果:11例下颌骨髁突骨软骨瘤病例CT显示肿瘤与病变髁突无明显分界(8/11)或与患侧髁突有蒂相连(3/11);肿瘤骨皮质及骨髓腔均与患侧髁突相续,瘤体表面均有特征性薄层软骨帽覆盖,瘤体外周密度通常高于中心;瘤体周围均有薄层软组织包绕。患侧颞骨关节面表面均有明显矿化,且因受瘤体压迫改建而较对侧平坦,患侧关节上、下腔间隙较对侧明显变窄;肿瘤生长方向不尽相同。8例单侧下颌骨髁突增生病例CT显示髁突颈部和(或)下颌支延长,髁突形状改变;增生的髁突外周骨皮质均有不同程度的骨化,硬化层厚度较对侧大;骨髓腔密度较不均匀。结论:CT检查能有效提供病变髁突及其周围软硬组织情况,为鉴别诊断下颌骨髁突骨软骨瘤和单侧下颌骨髁突增生提供良好的依据。

Comparison of CT features in patients with mandibular condylar osteochondroma and unilateral mandibular condylar hyperplasia

PURPOSE: To evaluate the CT features in patients with mandibular condylar osteochondroma and unilateral mandibular condylar hyperplasia.METHODS: Eleven patients with mandibular condylar osteochondroma and 8 patients with unilateral mandibular condylar hyperplasia were included in this study.The CT data was evaluated retrospectively.The evaluation indices included the size,extent of the lesions as well as the changes of the soft and hard tissues adjacent to the lesions.RESULTS: CT scanning of 11 patients with mandibular condylar osteochondroma showed continuity of the exostotic bone marrow and cortex with that of the underlying bone and the lesion was pedunculated(3/11) or sessile(8/11).Cartilage-capped osseous projection was observed in all cases.Periphery of the tumour was denser than matrix of the tumour.A thin layer of soft tissue which had various thicknesses encircling the lesion in 11 cases could be delineated by CT scan.Outer calcified layer of the tumour could also be observed on CT scanning.The squamous temporal bone remodeled to accommodate the growing tumour.The tumour was observed on different aspect of the involved condyle.CT scanning of 8 patients with unilateral mandibular condylar hyperplasia exhibited elongation of the affected condylar neck and/or ramus.CT imaging also showed abnormalities in the morphology of the involved condylar head.Periphery of the hyperplasic condyles ossified to varying degrees and the density of intramedullary canal of bone was different.CONCLUSION: CT scanning could provide detailed information of the affected condyle as well as the adjacent soft and hard tissues and be useful imaging basis for distinguishing mandibular condylar osteochondroma and unilateral mandibular condylar hyperplasia.