骨母细胞瘤的MRI表现

MR imaging of osteoblastoma

目的 探讨骨母细胞瘤的MRI表现及MRI的诊断价值。方法 经病理证实的骨母细胞瘤 9例 ,良性 5例 ,恶性 4例 ,全部行MRI检查 ,3例同时行CT检查。结果 MRI主要表现 :T1WI呈等或稍低信号 ,T2WI呈以高信号为主的混杂信号 ;瘤内有钙化和骨化 (5 / 9) ,囊变 (6/ 9)及少量出血 (2 / 9) ,线样低信号间隔 (7/ 9)并可强化 (3 / 7) ;瘤周有低信号的骨性包壳 (9例 ) ;增强扫描肿瘤多明显强化。当肿瘤形态不规则 ,瘤内散在坏死和出血灶 ,不均匀强化 ,伴有骨膜反应、软组织肿块时 ,提示恶性可能。结论 MRI有助于骨母细胞瘤的定位及定性诊断 ,并对肿瘤的良恶性鉴别有一定提示作用。

Objective To evaluate the MRI findings in diagnosing osteoblastoma. Methods Nine cases of osteoblastoma, 5 benign cases and 4 malignant cases, proved pathologically were collected. All patients were imaged with MRI, and 3 cases with CT as well. Results All tumors were intermediate or slightly hypointense signal on T1WI and inhomogeneous with mixed intermediate and high signal intensity on T2WI, predominantly high. Calcification or ossification were found in 5 cases. Cystic changes and hemorrhage were seen in 6 cases. The capsule was identified as a low intensity ring around the tumor on T1WI and T2WI. Low intensity linear partition was found in 7 cases, and 3 of them showed enhancement. On enhanced scan, the tumors enhanced distinctly. Findings clued to malignant osteoblastoma including irregular focus with small cystic changes and hemorrhage, inhomogeneous enhancement, periosteum reaction and soft tissue masses. Conclusion MRI is useful in diagnosing osteoblastoma and in differentiating benign and malignant osteoblastoma.