自发性眶内出血的影像表现

目的 分析自发性眶内出血的影像表现,探讨不同影像技术对其诊断的价值.方法 回顾性分析30例经手术病理或穿刺证实的自发性眶内出血的超声、CT和MRI表现,并与病理或临床结果进行对照分析.结果 30例中18例经手术证实,其中单纯性血囊肿6例,静脉性血管瘤伴血囊肿形成10例(畸形血管位于肌肉圆锥内7例,眼外肌3例),静脉曲张伴血囊肿形成2例(畸形血管位于肌肉圆锥内、眼外肌各1例),另12例由穿刺证实.30例自发性眶内出血在超声上均表现为回声不均匀的囊性结构伴轻度可压缩性,且内部无血流.所有病例在CT平扫上均表现为等或稍高密度影,缺乏特征性,但病灶的CT值随着时间的推移具有下降趋势,其中发病1～3 d者4例,CT值为82.0～89.0 HU,发病4～20 d者20例,CT值为69.0～82.0 HU;发病21 d至2个月者6例,CT值为30.0～37.0 HU.在MRI上,病灶具有典型的血肿信号特征及演变规律,发病1～3 d(4例),T1WI呈等信号,T2WI呈明显的低信号;发病4～10 d(10例),T1WI上病灶内部出现高信号区,T2WI上仍呈低信号;发病11～20 d(10例),T1WI呈均匀或不均匀高信号,T2WI上呈均匀高信号;发病21 d至2个月(6例),T1WI和T2WI上均呈高、低混杂信号表现.超声、CT平扫和MRI对自发性眶内出血诊断的临床符合率分别为96.7%(29/30)、26.7%(8/30)和100%(30/30),但均难以区分单纯性和继发性眶内血肿.结论 MRI对自发性眶内出血的诊断以及对血肿引起的继发性改变的评价作用均优于超声和CT.

The imaging manifestations of spontaneous orbital hemorrhage

Objective To study the imaging manifestations of spontaneous orbital hemorrhage and to evaluate the diagnostic values of different imaging techniques.Methods The manifestations of ultrasound,CT and MRI in 30 patients with spontaneous orbital hemorrhage confirmed by surgery or puncture were retrospectively analyzed.Then the imaging data were compared with pathological or clinical results.Results Eighteen of 30 patients were surgically confirmed, including 6 cases of simple blood cysts, 10 cases of venous angioma with hematocysts ( 7 cases in the intraconal space and 3 cases within the extraocular muscle),2 cases of varicosity with hernatocysts ( 1 case in the intraconat space and another case within the extraocular muscle).Twelve patients were proved by puncture.The sonngraphie features of the spontaneous orbital hemorrhage in all 30 cases were inhomogeneons and slightly compressible cysts without blood flow in them.The CT manifestation of the lesions was lack of specificity and showed isodensity or slight hyperdensity,however, the CT value of the lesions had the tendency of decrease over time.The CT values were 82.0 to 89.0 HU in 4 cases with the courses of 1-3 days.And when the hemorrhage courses were 4-20 days,21-60 days, the CT values were 69.0 to 82.0 HU (20 cases) and 30.0 to 37.0 HU (6 cases),respectively.On MRI, the lesions showed typical signal characteristics and evolution of hematomas.For 1-3 days (4 cases), the lesions showed isointensity on T1WI and hypointensity on T2WI; for 4-10 days (10 cases), the lesions appeared hyperintensity in the central zone on T1WI and still showed hypointensity on T2WI; for 11-20 days( 10 cases), the lesions was homogeneous or inhomogeneous hyperintensity on T1WI and homogeneous hyperintensity on T2WI; and for 21-60 days (6 eases), the lesions showed heterogeneous intensity on both T1 WI and T2WI.The coincidence rates with clinical diagnoses were 96.7% (29/30) for ultrasound, 26.7% (8/30)for CT and 100% (30/30) for MRI, but they all showed limited ability in distinguishing simple from secondary orbital hemorrhage.Conclusion MRI is superior to ultrasound and CT in diagnosing spontaneous orbital hemorrhage and evaluating the secondary changes.