眼眶海绵状血管瘤的CT诊断

CT Diagnosis of Orbital Hemangioma

目的：研究眼眶海绵状血管瘤的ＣＴ表现及其诊断价值。材料和方法：对５５例眼眶海绵状血管瘤ＣＴ图像进行回顾性分析。结果：４５例肿块位于眼眶肌锥内，２例深达眶尖部；另１０例占据肌锥内外或仅发生于肌锥外。横断面扫描显示３４例肿块位于眼球后，其中２０例紧贴球后壁；冠状位扫描较难分辨眼球与球后肿瘤的前后界限。横断面扫描中，肿瘤与视神经、眼外肌界限不清；但在冠状位可显示两者受压移位。４３例肿瘤为类圆形或椭圆形，边界清晰，１０例呈不规则或团块状，且边界欠清，另２例两个瘤体呈哑铃状相连。３８例密度不均或欠均，其中６例有高密度斑点或片状阴影，２例为钙化或静脉石。３０例增强后扫描中２０例部分增强明显，且增强后肿瘤的边界、形态、大小更加清楚。结论：横断面在辨别肿瘤与眼眶及眼球的关系，冠状位在区分肿瘤与视神经、眼外肌时各有优势，增强扫描有助于提高血管瘤的ＣＴ诊断率。将横断面增强扫描和冠状位平扫相结合，能使ＣＴ检查对血管瘤的定位、定量及定性诊断的准确率明显提高。

Purpose: To investigate the CT features and to assess the value of computed tomography(CT)in evaluation of orbital cavernous hemangioma (OCH). Materials and Methods: CT findings of 55cases with OCH were retrospectively analyzed. Results: Of 55 OCHs, 45 were located within the orbital cone, and 10 were outside or partly inside and partly outside the cone. The relation between the OCH and the eyeball was revealed clearly on axial images , but not on coronal images; contrarily, the relation between the OCH and the optical nerve or extraocular muscles was showed well on coronal images, hut not on the axial images. Thirty - eight tumors were found behind the eyeball , and 20 of them were closed to the posterior wall of eyeball. Forty - three tumors were oval or round with a clear boundary , and 10 OCHs appeared as irregular mass lesions with obscure boundary. The rest 2 OCHs were hourglass in shape. The density of tumors was not uniform in 38 cases. Spotty or Iumpy high - density areas within the tumors were found in 6 of them, in which 2 had calcifications or phlebolithes. Twenty of 30 cases were heterogeneously enhanced on post - contrast images. Conclusion: The relation between the tumor and the orbit or eyeball is usually demonstrated more clearly on axial images the on coronal images, but the coronal view has the advantage of distinguishing the tumor from the optical nerve. Contrast enhancement is helpful to improve the diagnostic accuracy in the diagnosis of the OCH. It is of great benefit to improve the abilities of lo- calization, quantification and qualification in the diagnosis of the OCH, when both the axial and coronal images are viewed at same time.