视神经鞘脑膜瘤影像学研究

头颈部放射学

作者单位:100730首都医科大学附属北京同仁医院放射科(鲜军舫、王振常、于文玲、满凤媛),眼科中心(安裕志、史季桐、李彬),神经外科(张天明)

视神经鞘脑膜瘤影像学研究

鲜军舫 王振常 安裕志 于文玲满凤媛 张天明 史季桐 李彬

摘要! 目的 研究视神经鞘脑膜瘤的CT 和M RI 表现,并探讨双轨征的显示情况及其价值。方法 35例经手术病理证实的视神经鞘脑膜瘤患者,年龄6~71岁,女20例,男15例。28例行CT 扫描,其中25例行增强扫描;27例行M R 扫描,其中25例行增强扫描。结果 35例视神经鞘脑膜瘤中12例呈梭形,7例呈管形增粗,1例呈椭圆形,8例为偏心性生长的肿块,7例弥漫累及整个眼眶。35例均累及眶内段,其中22例同时累及管内段,13例同时累及颅内段,4例同时累及视交叉,1例同时累及视束。行CT 扫描的28例中,20例呈等密度,8例为含有钙化的肿块。行CT 增强扫描的25例全部强化,其中6例清楚显示双轨征。行M R 扫描的27例中,16例T 1W I 和T 2WI 均为低信号,3例呈长T 1、长T 2信号,8例呈等T 1、等T 2信号。行M R 增强扫描的25例均呈明显强化,17例清楚显示双轨征。经统计学处理,M RI 显示双轨征明显优于CT (P =0 001)。结论 CT 和M R I 都可显示视神经鞘脑膜瘤的部位、形态和内部特征,M RI 在定位诊断和定性诊断方面明显优于CT 。

关键词! 视神经; 脑膜瘤; 体层摄影术,X 线计算机; 磁共振成像

Imaging investigations of meningiom as of optic nerve sheath XIA N Jun f ang *,WA N G Zhen chang ,A N Y u z hi ,Y U W en ling,M A N Feng y uan,ZH A N G T ian ming,SH I J i tong ,L I Bin *Dep art ment of R adiology ,Cap ital Univer sity of Medical Sciences A f f iliated Beij ing T ongren H osp ital ,Beij ing 100730,China

Abstract ! Objective T o investig ate CT and M R imag ing findings of mening iomas of optic nerv e sheath,and to ev aluate t he ∀tram track #sig n and its clinical significance Methods CT and M R imag ing findings of thirty five patients w ith meningio mas of o ptic nerve sheath confirmed by histopathology w er e analyzed r etrospectively T he age of t he patients was from 6to 71years (mean age 41 63years) T her e w ere 20females and 15males CT scanning was perfo rmed in 28patients w ith contr ast scanning in 25,and M R imaging w as perfo rmed in 27patients w ith contrast scanning in 25 Results O f the 35cases with mening iomas of optic nerve sheath,fusiform thickening mass was found on CT and/or M R imaging in 12cases,diffuse tubular enlar gement mass in 7,ovoid mass in 1,localized eccentric ex pansion in 8,and large diffuse irr egular mass w ithin the orbit in 7 Enlarg ement of intraorbital segment of t he optic nerv e was seen in all 35cases,enlargement of intracanalicular segment simultaneously in 22,enlargement of intracranial seg ment simultaneously in 13,mass of opt ic chiasm simultaneously in 4,and enlar gement of optic tract simultaneously in 1 CT scanning per for med in 28patients showed iso density mass in 20and mass containing calcification in 8 Enhancement of the tumor w as observed on post co ntrast CT in all 25,and t he ∀tram t rack #sign was clearly seen in 6 M R imaging performed in 27patients displayed hypointense mass on T 1 and T 2 weig hted images in 16,isointense mass on T 1 and T 2 weighted images in 8,and long T 1and long T 2signal intensity mass in 3 After contrast,mar ked enhancement of the mass was seen in all 25cases,and the ∀tram track #sign was clearly demonstrated in 17 By way of statist ical analysis,M R imaging was super ior to CT in demonstrating the ∀tram track #sign (P =0 001) C onclusion CT and M R imaging could demonstrate the site,configuration,and character istics of the tumor M R imag ing was superior to CT in the diagnosis of meningiomas of optic ner ve sheath

Key words ! Opt ic nerve; M eningioma; T omogr aphy,X ray computed; M agnetic resonance imag ing

视神经鞘脑膜瘤是原发于视神经鞘的肿瘤,影响患者的视力和健康,不少患者还可因肿瘤向颅内发展而死亡。虽然CT 和MRI 较有特点,国内也有文章提及[1,2],但部分视神经鞘脑膜瘤与视神经胶质瘤或视神经炎等的鉴别较为困难[3 5];另一方面国内亦未见有关视神经鞘脑膜瘤影像学研究的专门