1、早读片 主班：江远亮指导老师：刘崎教授病例 57岁女性 2001年起反复发作左侧肢体活动不利索和频繁头痛 2004年磁共振检查发现左侧大脑半球异常信号 其他病史无特殊，神经系统检查及 实验室各项检查均阴性T2WI 2010年磁共振 fluid-attenuated inversion recoveryDWIfluid-attenuated inversion recovery 2004年磁共振T2WIdiagnosis Extensive Unilateral Widening of Virchow-Robin SpacesVirchow-Robin Spacesat MR ImagingIn
2、troduction named after Rudolf Virchow(German pathologist,18211902)(1)and Charles Philippe Robin(French anatomist,18211885)perivascular spaces/血管周围淋巴间隙Anatomy VR spaces surround the walls of arteries,arterioles,veins,and venules as they course from the subarachnoid space through the brain parenchyma
3、Electron microscopy and tracer studies have given insight into the location of VR spaces and clarified that the subarachnoid space does not communicate directly with the VR spacesVirchow-Robin spaces on magnetic resonance images:normative data,their dilatation,and a review of the literature Neurorad
4、iology(2006)48:745754Prevalence Small VR spaces(2 mm)appear in all age groups.With advancing age,VR spaces are found with increasing frequency and larger apparent size(2 mm)MR technique：Heavier T2-weighted imaging,thinner sections,high-field-strength MRDilated VR Spaces Dilatation of VR spaces was d
5、escribed by Durant-Fardel in 1843 （3mm）The mechanisms underlying expanding VR spaces are still unknown dVRS is an indicator of cerebral small vessel diseases such as leukoaraiosis and lacune.Locations and Morphology Dilated VR spaces typically occur in three characteristic locations type I type II t
6、ype III The first type(type I)is frequently seen on MR images and appears along the lenticulostriate arteries entering the basal ganglia through the anterior perforated substancea Basal view of the cadaveric brain.Arrows indicate the basalsegment of the V-R spaces.OC optic chiasm,M mamillary body,Pp
7、ons,I olfactory nerve,III oculomotor nerve.b,c Coronal 3 T MRimages showing the basal segment of the V-R spaces(arrows)The second type(type II)can be found along the path of the perforating medullary arteries as they enter the cortical gray matter over the high convexities and extend into the white
8、matter The third type(type III)appears in the midbrain.In the lower midbrain,VR spaces at the pontomesencephalic junction surround the penetrating branches of the collicular and accessory collicular arteriesAppearance at MR Imaging well-defined oval,rounded,or tubular structures,smooth margins,commo
9、nly appear bilaterally,and usually measure 5 mm or less Visually,the signal intensities of the VR spaces are identical to those of CSF with all pulse sequencesAtypical VR Spaces Occasionally,VR spaces appear markedly enlarged,cause mass effect,and assume bizarre cystic configurations that may be mis
10、interpreted as other pathologic processes,most often a cystic neoplasmGiant VR spaces in the mesencephalothalamic region in a 19-year-old manShiratori K,Mrowka M,Toussaint A,SpalkeG,Bien S.Extreme,unilateral wideningVirchow-Robin spaces:case report.Neuroradiology2002;44(12):990992.DifferentialDiagno
11、stic Considerations Lacunar Infarctions Cystic Periventricular Leukomalacia Multiple Sclerosis Cryptococcosis Mucopolysaccharidoses Cystic Neoplasms Neurocysticercosis Arachnoid Cysts Neuroepithelial CystsLacunar InfarctionsVs type II Vs type III Lacunar InfarctionsVs type I Periventricular Leukomal
12、acia usually seen in premature infants,is a leukoencephalopathy resulting from a pre-or perinatal hypoxic-ischemic event acute stage/End-stage(a typical appearance at MR imaging)Symmetrical/compensatory focal ventricularEnlargement/Corpus callosal thinning/surrounding gliosisPeriventricular Leukomal
13、aciaCystic periventricular leukomalacia in a 3-year-old boy with a history of perinatal asphyxia who had delayed motor and mental development and epilepsyOvoid MS lesion of the centrum semiovale in a 49-year-old manParenchymal neurocysticercosisin the vesicular stage in a 17-year-old boyCryptococcos
14、is in a 58-year-oldwoman with headaches and fever who wasseropositive for human immunodeficiencyvirus.Parasagittal T2-weighted image(5963/120)shows multiple dilated VR spaces inthe region of the basal ganglia(arrowheads).C neoformans was cultured from the CSF.Hurler syndrome(mucopolysaccharidosis ty
15、pe I)in a 2-year-old boy with typicalexternal features of this syndromeDesmoplastic pilocytic astrocytoma of the right thalamus,cerebral peduncle,and brainstem in a 15-year-old girlNeuroepithelial Cysts rare and benign lesions/etiology controversial Pathologic studies ependymal in origin spherical t
16、o ovoid,measure up to several centimeters in size,and may have mass effect the lateral ventricles or fourth ventricle/the cerebral hemispheres,thalamus,midbrain,pons and cerebellarvermis,the medial temporal lobe in or near the choroidal fissure by pathologic studyNeuroepithelial cyst of the thalamus
17、in a 53-year-old woman with migraineheadachesNeuroepithelial cyst of the cerebral peduncle and pons in a 60-year-old womanwith epilepsyChoroidal fissure cyst in a1-week-old boyConclusionsVR spaces surround the walls of arteries,arterioles,veins,and venules as they course from the subarachnoid space
18、through the brain parenchymaSmall VR spaces(2 mm)Visually,the signal intensities of the VR spaces are identical to those of CSF with all pulse sequencesDilated VR spaces typically occur in three characteristic locationsOccasionally,VR spaces appear markedly enlarged,cause mass effect,and assume bizarre cystic configurations that may be misinterpreted as other pathologic processes,most often a cystic neoplasmReferencesCase-Radiology:Volume 270:Number 2February 2014Review-RadioGraphics 2007;27:10711086
