【作者】 丁强；

【导师】 何彦津；

【作者基本信息】 天津医科大学 ， 眼眶病临床和影像诊断， 2004， 硕士

【摘要】 目的：研究B超、彩色多普勒影像、CT和MRI在鉴别诊断不同原因引起的眼外肌肥大中的价值。 方法：回顾性分析2002．1．1～2002．12．3 1期间CT显示有眼外肌肥大的156例眼眶病患者的影像资料。 结果： 1．甲状腺相关眼病（Thyroid associated ophthalmopathy，TAO）和特发性眼眶炎性假瘤（idiopathic orbital inflammatory pseudotumor，IOIP）TAO在CT上主要表现为双侧多条眼外肌对称性梭形肥大，止端正常，边缘锐利，肌肉受累由多到少依次为下直肌、内直肌、上直肌和外直肌，常伴有眶隔前突；不典型病例可为单条眼外肌受累，止端增厚，泪腺肿大等。IOIP引起眼外肌肥大的CT影像常表现为一条眼外肌不对称梭形肥大，止端增厚，多累及外直肌、内直肌和下直肌，常伴有泪腺肿大，眶脂肪浸润；部分病例可见双侧多条眼外肌受累，边缘光滑，甚至止端正常。两者多引起中度以上肌肉肥大。B超扫描均表现为肌腹呈中低回声肥大，本文只有少数资料显示肌止端，前者显示正常，后者增厚较明显。2例IOIP在彩色多普勒影像（colored Dopplor imaging，CDI）均未显示肌肉内有血流信号。两者在MRI上形态特点与CT类似，T₁WI呈中低信号，T₂WI呈中高信号。 2．眼眶外伤和颈动脉海绵窦瘘（carotid cavernous fistula，CCF）两者CT扫描都显示单侧眼眶多条眼外肌轻中度肥大，边界稍模糊，止端多正常。前者可见眶壁骨折，后者有眼上静脉增粗。2例眼眶外伤者B超显示肌肉轻度肥厚，边缘不规则，呈中低回声。3例眼眶外伤者MRI未显示肌肉肥大。 3．囊虫病、发生于肌肉内的肿瘤、转移性肿瘤、纤维组织细 同等学力申请硕士研究生专业学位论文胞瘤和良性血管外皮瘤本组病例CT影像均表现为单条肌肉的高度肥大，呈不规则梭形，止端增厚，多数边缘清晰。囊虫累及肌肉则显示肌肉内低密度区中有高密度斑点。2例肌内血管瘤B超表现为止端增厚，内回声不均，后部回声少，中等声衰减，边界清楚。其中静脉性血管瘤CDI呈现特殊的红、蓝血流混杂现象。纤维组织细胞瘤和良性血管外皮瘤各1例，B超显示肿瘤与肌肉无法分辨，均呈低回声，前者声衰减不明显，后者衰减较著;两者的CD工均显示较丰富的血流信号。2例转移癌B超呈低回声，后界显示不清;其中1例有CDI者，病变内未见血流信号。2例转移癌有MRI资料，TIW工呈中信号，TZW工呈中低信号。 4.泪腺肿瘤腺样囊性癌CT显示泪腺区肿物，与外直肌分不清，B超和CDI未显示肌肉影像及其血流信号，3例有MR工者显示外直肌基本正常。泪腺多形性腺瘤CT影像呈条索样轻度增粗，止端受累，可见泪腺肿物。B超和CDI描述仅为肿瘤改变，无眼外肌描述。 5.静脉性血管畸形、动静脉血管瘤和眶内自发出血静脉性血管畸形1例CT表现为内直肌高度肥大，形态类似原发于眼外肌内肿瘤，但密度不均;1例显示内直肌轻度梭形肥厚，止端正常。1例动静脉血管瘤显示肌肉条索状轻中度增粗，止端受累，同时显示肿瘤影像。其余病例均为肌腹不规则结节状增粗，类似转移性肿瘤。1例眶内自发出血B超显示肌腹肥大的无回声区，CDI仅在肌肉边缘有少量血流信号。2例眶内自发出血MRI显示肌肉轻度肥大，可与出血分开;其中1例T，WI呈中低信号，TZW工呈不均匀中高信号，另1例在TZwl可见低信号内有不规则高信号。 6.其它包括眶内继发肿瘤和其他原发肿瘤，均单侧受累。CT影像，结膜恶性黑色素瘤、眶内恶性上皮肿瘤、内生乳头状瘤和复 同等学力申请硕士研究生专业学位论文发脑膜瘤累及肌肉均为轻度条索状增粗，止端受累;筛窦鳞状细胞癌和额筛窦粘液囊肿累及的肌肉为梭形轻度增粗，边缘模糊。海绵状血管瘤的受累肌肉呈均匀的轻度增粗，止端正常。本组病例均可见明显的原发病改变。B超、cDI均未涉及肌肉的变化。复发脑膜瘤累及内、外直肌，在T，w工呈中信号，TZw工呈中低信号。 结论: 1.TAO、工O工P、眼眶外伤、CCF和猪囊虫病仅通过CT影像就可以明确诊断。TAO、工O工P中单条肥大眼外肌的不典型改变，即使结合其他影像检查，两者也难以区别。 2.在泪腺肿瘤、上皮植入性囊肿、静脉性血管畸形、眶内自发出血、额筛窦囊肿、海绵状血管瘤中，cT结合B超、CDI或MRI多可明确诊断。 3.引起眼外肌高度肥大的其它病种，仅从CT影像无法诊断，但结合B超、CD工或MRI常可作出初步诊断，明确诊断一般需要活检。 总之，各种影像学检查可从不同的侧面反映病变的组织结构特点，不同影像学检查方法的联合对各种原因引起的眼外肌肥大的鉴别诊断有非常重要的意义。更多还原

【Abstract】 Object: To investigate the value of B-scan, CDI, CT and MRIin differentiation of extraocular muscle enlargement causedby various diseases.Methods: Retrospective analysis from January 1st 2002 toDecember 31ST 2002 of imaging materials of 156 cases withenlarged extraocular muscles on CT scans.Results:1. Thyroid associated ophthalmopathy (TAO) and idiopathic orbital inflammatory pseudotumor (IOIP) CT-scan showed extraocular muscles of TAO were symmetrically enlarged with a fusiform shape. Insertion was normal in most cases, bilateral and multiple muscles involvement were more common. The margin was sharp. The frequency of specific muscle involvement in descending order were the inferior rectus, medial rectus, superior rectus and lateral rectus. Sparing tendon and a single enlarged muscle were displayed in some atypical cases. In IOIP, unilaterality, single muscle involvement, enlargement of the tendon were seen commonly. The border was usually blurred. However, bilaterality, multiple muscle involvement, sparing of the tendon were also found in IOIP. The lateral rectus was found to be most commonly involved followed by medial rectus, inferior rectus. Moderate and severe enlargement were usually observed in TAO and IOIP. B-scan showed medium-low internal reflectivity of enlarged belly in TAO and IOIP. The former had a normalinsertion and the latter had a thickened insertion. Two cases with IOIP were showed no flow signal on CDI. The enlarged muscles, compared with soft tissues, weie isointense on Ti-weighted scans and less hyperintense on T2~weighted images.2. Orbital trauma and carotid cavernous fistula (CCF) Unilateral and mild enlargement of multiple muscles were showed on CT-scan in orbital trauma and CCF. A blurred border and spared tendon were often observed. -The fracture and enlargement of superior ophthalmic vein was seen in orbital trauma and CCF, respectively. B-scan showed mild muscle belly enlargement with irregularity in the border, mild and moderate echoes in trauma. It showed no enlargement of muscle on MRI in three cases of trauma.3. Cysticercosis, intramuscular tumors, metastatic tumors, fibrous histiocytomas and a benign hemangioperic -ytoma One single marked enlarge muscle, irregular fusiform shape and thickened insertion were features on CT in the diseases of mentioned above. A hyperintense spot in low intense muscular belly was a feature on CT of cysticercosis. A thickened tendon insertion , focal heterogeneities of internal reflectivity and tapered echoes were seen on B-scan in two cases with intramuscular hemangioma. A kind of special phenomena of red and blue flood flow cycling each other was showed on CDI in a case with intramuscular venous hemangioma. Of a fibroushistiocytoraa and a benign hemangiopericytoma, the muscle and the tumor were not distinguished on IB-scan, and had a medium-low echography. Abundant flood flow signals were observed on GDI in a fibrous histiocytoma and a benign hemangiopericytoma. A low internal echo and a blurred back border were found on B-scan in two metastatic tumors. No flood flow signal was found in one case by GDI. On MRI, a case of metastatic tumors had medium-low signals in Ti-weight scan, medium signals in T2-weight scan. The another case was showed heterogeneities.4. Benign pleomorphic adenoma and adenocystic carcino -mas of lacrimal gland An enlargement mass was indistin -guished from lateral rectus on CT in cases with adenocystic carcinoma. The shape of lateral rectus muscle was basically normal basically on MRI. In benign pleomorphic adenoma, a mild ribbon-shaped enlargement of lateral rectus and insertion involved were found on CT. Both of B-scan and GDI showed no pictures of involved muscles in these two di seases.5. Venous vascular malformation, ateriovenous hemang -ioma and intraorbital spontaneous hemorrhage In one case with venous vascular malformation, medial rectus muscle was showed a marked irregularly enlargement on CT-scan, with an internal heterogeneity. Another one was dis更多还原