Demyelinating Diseases of the Central Nervous System

中枢神经系统脱髓鞘疾病DemyelinatingDiseasesoftheCentralNervousSystem,哈医大二院神经科,Chapter1Intraduction,1.ConceptAgroupofdiseasesofthebrainandspinalcordinwhichdemyelinationisaprominentfeature.,2.PathologicFindingsDestructionofthemyelinsheathsofnerves;Infiltrationofinflammatorycellsinaperivasculardistribution;,Aparticulardistributionoflesion,oftenperivenousandprimarilyinwhitematter,eitherinmultiplesmalldisseminatedfociorinlargerfoci;Arelativeintegrityoftheaxiscylindersinthelesionsandalackofwallerian,thesecondarydegenerationoffibertracts.,多发性硬化MultipleSclerosis,1.ConceptMultipleSclerosisisakindofautoimmunediseasescharacterizedbydemyelinationofCNS.Duetoitshighincidence,chronicityandtendencytoattackyoungadults,ithasbecomeoneofthemostimportantdiseasesofCNS.,2.EtiologyAndPathogenesis,1)病毒感染及自身免疫反应：麻疹病毒、人类噬T淋巴细胞病毒(HTLV-I)分子模拟、细胞免疫、体液免疫(1,2,3,4)2)遗传因素(inheritedfactor)3)环境因素(environment)(4),3.Epidemiology,IncidenceofMSassociatedwithlatitude.ContactingwithsomekindofenvironmentmayplayanimportantroleintheincidenceofMS.,Hereditymaybeanimportantfactor.MSassociatedwiththeHLA-DRlocusonthesixthchromosome,HLA-DR2expressstronglyandthen-DR3,B7andA3.,4.PathologicFindings,Characteristic:MultipledemyelinatedplaquesinwhitematterofCNS.Position:Whitematteraroundthelateralventriclesandspinalcord,opticnerve,brainstemandcerebellar.Acutestage:hyperemia,ondema,demyelination,infiltrationofinflammatorycellsinperivasculardistribution.Recoverystage:Astrocyteproliferition,formingofastrocyticscab.,小脑及桥脑脱髓鞘病灶,桥脑脱髓鞘病灶,5.ClinicalManifestations,1)Prodrome:Thesymptomsevolvedmoreslowly,overseveralweeksormonths.2)AcuteorsubacuteonsetRelapsing-remitting.3)Earlysymptomsandsigns:Weaknessornumbness,sometimesboth,inoneormorelimbsistheinitialsymptominabouthalfofthepatients;,Thevisuallossinoneorbotheyes;Nystagmus(fig1)andpalsyofeyemuscles(internuclearophthalmoplegia,oneandahalfsyndrome)Impairmentofotherbrainnerves;Ataxia:CharcotssyndromSensationdisorder:Rombergssign,Lhermittessign;AttacksyndromOtherclinicalfeature,6.LaboratoryandotherassistantTests,1.CSFTest1)NumberofMNC0.7;oligoclonalbands(OB)positive;3)MBP,PLP,MAG,MOGAbsandAb-secretingcells4)CSF-Alb/serum-Alb1.7(probabilityofMS),2.Evokedpotentials:visualevokedpotentials(VEP);brainstemauditoryevokedpotentials(BAEP);somatosensoryevokedpotentials(SEP).3.MRI:preiventricularplaques;regularplaquesinbrainstem,cerebellumandspinalcord;atrophysymptom.(1,2,3,4,5,6),Diagnosticcriteria,1.ClinicaldefiniteMS(CDMS):twotimesofattackandtwolesions;twoattacks,onelesionandonesubclinicalevidence;2.LaboratorysupporteddefiniteMS(LSDMS):Twoattacks,onesubclinicalevidenceandCSF/OB/IgG;Oneattack,twolesionsandCSFOB/IgG;Oneattack,onelesion,onesubclinicalevidenceandCSFOB/IgG;,3.ClinicalprobableMS(CPMS):twoattacks,onelesion;oneattack,twolesions;oneattack,onelesionandothersubclinicalevidence;4.LaboratorysupportedprobableMS(LSPMS)Twoattacks;CSFOB/IgG;TwoattacksinvolvingdifferentpartofCNS,intermissionatlestonemonth;eachattackmustcontinuefor24hs.,DifferentialDiagnosis,1.急性播散性脑脊髓炎2.脑动脉炎、脑干炎、脊髓血管畸形3.颈椎病脊髓型4.热带痉挛性截瘫5.大脑淋巴瘤,Treatment,目前尚无一种特效疗法，治疗的主要目的是：1.急性活动期抑制其炎症性脱髓鞘过程，遏止病情的进展。2.尽量预防能促发的外因，减少复发次数，延长缓解间歇期。3.预防并发症。4.对症及支持疗法。,1.Relapsing-RemittingMS：ACTHandSteoids：methylprenisolone,prednison,dexamethasone;IFN-;Azathioprine；Immuneglublin（Ig).,2.ProgressiveMS：Methotrexate,MTX;Cyclosphoamide;CyclosporineA;Plasmatransplantation.3.对症治疗及预防感染避免疲劳：如过度劳累、紧张、疫苗接种、妊娠、分娩等。,视神经脊髓炎(Neuromyelitisoptica,NMO),1.Introduction：AcuteorsubacutedemyelinatingdiseaseinvolvedopticNandspinalcordatthesametime.2.EtiologyAndPathogenesis：与遗传素质和种族差异有关。西方-脑干；东方-视神经和脊髓；25%MS突发球后视神经炎；多方研究证实白种人对MS易感；非白种人对NMO易感。3.Pathology：Demyelination,plaqueofsclerosis,infiltriationofinflammatorycellsinperivasculardistribution.视神经、视交叉及胸颈段易受累。,颈髓脱髓鞘视神经炎,ClinicalManifestations,1、年轻居多，21-41岁。2、特征：急性横贯性脊髓炎和双侧同时或相继出现的ON。70%可在数日内有截瘫。3、急性起病可在数小时或数日内单或双眼失明，眼眶痛。4、脊髓症状可横贯、不对称、或呈播散性；特征为快速进展的双下肢瘫，感觉脱失平面、括约肌障碍等，1/3病人有Lhermitte征、根痛。,一、辅助检查1、CSF细胞数增加，73%单相、82%复发。2、复发病人脊髓MRI88%出现纵向融合超过数个节段，钆强化和肿胀常见。二、鉴别诊断1、单纯球后神经炎2、MS表现为NMO临床模式。3、亚急性视神经病三、治疗大剂量甲强冲击疗法,急性播散性脑脊髓炎（ADEM）,1、概述：是一种广泛累及脑和脊髓白质的急性炎症性疾病(感染出疹或疫苗接种)爆发型：急性出血性白质脑炎(AHL)2、病因及发病机制：病毒感染，脑组织+FAC可诱发EAE，认为ADEM是急性MS，或其变异型。3、病理：脑和脊髓多数脱髓鞘病灶，小静脉周围炎性反应，形成血管袖套。,ClinicalManifestations,1.Prodrome2.Typeofencephalitis3.Typeofmeningitis4.Typeofmyelitis,1.LabTeste1)WBC,pressureofCSFornormal,Pr,IgGandOBpositive;2)AbnormalofEEG;3)CTscanshowsthelesionsofmultiplediffusionsubcortexlowdensity;MRIs