软骨母细胞瘤影像学特征及其病理基础

目的 分析软骨母细胞瘤(chondroblastoma,CB)影像表现与病理的关系,以提高对该病的诊断准确性.资料与方法 回顾性分析经手术病理证实的原发性骨骼CB 15例,术前分别行X线平片、CT平扫、MR SET_1WI、T_1WI和SE T_1WI增强扫描.复习影像学图像并与手术病理作对照.结果 15例中,13例位于长管状骨(骨骺12例,干骺端1例),1例位于脊柱椎体及附件,1例位于跟骨.肿瘤直径3.9～7.2 cm,平均5.1 cm.均为溶骨性骨质破坏,无明显膨胀性改变.14例病灶边缘隐约呈结节状突起,可见明显硬化边,1例位于跟骨者无明显硬化边缘.位于管状骨者,病灶多位于骨骺中心骨性关节面下,8例可见钙化,5例无明显钙化;位于椎体和跟骨者,均无明显钙化;1例位于跟骨者,内可见小囊变;1例位于脊柱者可见骨性分隔.5例伴有软组织肿胀.CT示病灶密度略低、等或略高于邻近软组织密度,密度不均匀,CT显示细微钙化更有价值.MR T_1WI为低信号,T_2WI为低、等和高混杂信号,肿瘤边缘可见骨质硬化引起的低信号环.结论 CB不仅位于管状骨,也位于脊柱及跟骨等不规则骨.多数位于长管状骨骨骺中心或骨端骨突部位,肿瘤膨胀改变不明显,瘤内可见弓环状或斑点状钙化,边缘呈分叶结节状,常见明显硬化边,可伴有骨膜反应或邻近渗出,多数肿瘤可以确诊.位于脊柱与跟骨者表现不典型,容易误诊.

Analysis of the Radiologic Features Relative to Pathology in Chondroblastoma of Bone

Objective To explore the imaging features of chondroblastoma of bone and evaluate it's clinical value. Materials and Methods All 15 cases patients with chondroblastoma confirmed by surgical pathology underwent radiography, spiral CT plain scanning and MR SE-T_1 WI, FSE-T~2 WI and SE-T_1 WI enhancement scanning before operation. The imaging date was reviewed and analysed retrospectively in comparison with surgical and pathological results. Results 15 chondroblastoma with centrally or eccentriccally well defined osteolytic destruction were located at the long tubular bone (13, epiphysis or apophysis 12 ,metaphysis 1), vertebrae(1) and calcaneus(1) respectively. The diameter of the tumours was 3.9-7.2 cm (a mean diameter of 5.1 cm)with different degree ring and arc calcification (8) in the lesion, thin sclerotic rim(14) separated the tumor from adjacent normal bone,little periosteal reaction(1) and small soft tissue masses (5). The CT value was similar to muscle, CT is optimal to detect the matrix mineralization. MR imaging depicted low signal intensity with well defined on T,-weighting, iso to slight high signal intensity on T_2-weighting,and middle or high degree contrast enhancement on enhanced T_1-weighting. Conclusion The imaging manifestations of chondroblastoma were specific to some extent. Combined utilization of plain X-ray,CT,and MRI is helpful for the diagnosis and differential diagnosis of chondroblastoma.