儿童白瞳症的CT及MRI诊断

CT and MRI Diagnosis of Pediatric Leukokoria

目的:探讨CT和MRI对儿童白瞳症的诊断价值。方法;分析经临床综合检查诊断或手术病理确诊且资料完整32例患者的影像学表现,包括视网膜母细胞瘤(RB)18例,Coats病5例,永存性原始玻璃体增生症5例,早产儿视网膜病变3例,硬化性眼内炎1例。CT检查使用PickerIQ型CT机。MR检查应用GE0.7TOpenspeed开放超导磁共振设备,采用头相控阵线圈。扫描序列包括FSET2WI、SET1WI、FSEIR,增强后采用SET1WI,并应用预饱和脉冲脂肪抑制技术。结果:视网膜母细胞瘤,本组CT检查82.6%(19/23)显示钙化斑,玻璃体内伴有钙化的肿块是RB的重要CT征象。CT和MRI是肿瘤诊断、分期和术后随访的重要方法。CT和MRI显示自晶状体后缘至视盘纵向走行的索条影为永存性原始玻璃体增生症典型表现。明确的临床病史,双眼病变,无钙化,视盘区域视网膜脱离是诊断早产儿视网膜病变的主要影像学依据。男性,学龄期儿童或青少年,单眼病变,无钙化,眼球大小正常,眼球后部新月型高密度影是Coats病的特点。讨论:典型影像学表现结合患者年龄、性别、临床病史、单眼或双眼发病、眼球大小、眼内病灶的部位、病灶密度和信号变化、有无钙化等综合分析可以为临床提供比较准确的诊断信息。

Objective：To assess the value of CT and MRI in diagnosing pediatric leukokoria, Methods：CT and MRI findings of 32 cases of pediatric leukokoria confirmed by operation and clinical examination were analyzed,including retinoblastoma （ n= 18）, persistent hyperplastie primary vitreous （PHPV） （ n = 5 ）, retinopathy of prematurity （ROP） （ n = 3 ）, Coats disease （n=5） and sclerosing endophthalmitis （n=1 ）. plain and enhanced CT and MRI were performed. Results： Nearly one half of childhood leukokoria were caused by retinoblastoma, a malignant tumor of immature retinoblasts that manifested in a normal sized eye as a calcified mass. Retinoblastoma enhanced obviously after contrast agent injection and, unlike most tumors,may be darker than vitreous on T2WI. P HPV was a congenital, usually unilateral lesion tb.at appeared as a dense tubular mass extending from the lens to the retina along the course of the hyaloid canal. Hemorrhage from PHPV produced a subhyaloid or subretinal fluid collection,often with characteristic blood fluid levels. ROP was bilateral and usually manifested in premature infants who received supplemental oxygen therapy. Coats disease was a sporadic unilateral idiopathic retinal telangiectasia that produced a lipoproteinaceous subretinal exudate leading to complete retinal detachment. The globe had normal size but increased attenuation and signal intensity from hemorrhage without calcification or enhancement. Sclerosing endophthalmitis was a granulomatous reaction to the parasite in the vitreous and uveoretinal coat. Conclusion： Leukokoria is an abnormal pupillary light reflection that usually results from an intraocular abnormality and is seen most often in children. The typical CT and MRI findings combined with patient＇s age,sex,clinical history,unilateral or bilateral,size of eye, location of the lesion,density or signal changes and calcification will detect the cause of pediatric leukokoria accurately.