線粒體腦病教學(xué)教材

神經(jīng)影像病例匯報(bào)朱穎2009-10-20北大醫(yī)院醫(yī)學(xué)影像科Case12090748男，31歲主因“發(fā)作性視力下降，聽力下降伴癲癇5年，復(fù)發(fā)表達(dá)異常、聽理解異常3天”入院入院查體：發(fā)育差，身材偏瘦，言語欠流利，聽理解力障礙，命名障礙，查體欠合作。高級皮層功能查體不配合。四肢腱反射未引出。左側(cè)Babinski（+），右側(cè)（±）乳酸13.8↑（0.5-2mmol/l）（May-04，天壇）血mtDNAA3243突變陽性北大醫(yī)院醫(yī)學(xué)影像科Case2631976女，11歲“間斷抽搐伴視力下降2年，右側(cè)肢體活動(dòng)障礙1周”09-4入院2年來2此頻繁抽搐、類卒中樣發(fā)作，伴視力下降，頭痛、生長發(fā)育緩慢，智力落后、倒退。查體：身材矮小，頭圍小，計(jì)算力差，背部多毛，右眼內(nèi)斜，拖曳步態(tài)；肌力右側(cè)上下肢I(xiàn)V－，腱反射弱。腦電圖：異常肌電圖未見異常。乳酸高北大醫(yī)院醫(yī)學(xué)影像科線粒體病定義由于遺傳缺損引起線粒體代謝缺陷，導(dǎo)致ATP合成障礙，能量產(chǎn)生不足而出現(xiàn)的一組多系統(tǒng)疾病。分類線粒體病線粒體肌病線粒體腦肌病線粒體腦病CPEOKSSMERRFMELAS北大醫(yī)院醫(yī)學(xué)影像科MELAS發(fā)病機(jī)制血管病學(xué)說異常的線粒體沉積于軟腦膜和腦內(nèi)小動(dòng)脈的平滑肌細(xì)胞和內(nèi)皮細(xì)胞，導(dǎo)致腦組織缺血而致病細(xì)胞病學(xué)說線粒體功能障礙導(dǎo)致腦神經(jīng)細(xì)胞能量供應(yīng)不足，無氧代謝增加，乳酸酸中毒，當(dāng)能量需求增高時(shí)，即誘發(fā)卒中樣發(fā)作線粒體的氧化磷酸化異常最容易損傷枕葉非缺血性神經(jīng)血管細(xì)胞學(xué)說神經(jīng)元過度興奮、神經(jīng)元脆弱、毛細(xì)血管通透性增加和充血北大醫(yī)院醫(yī)學(xué)影像科MR表現(xiàn)游走皮質(zhì)受累為主頂枕顳多見不按腦血管分布鈣質(zhì)沉積基底節(jié)等腦內(nèi)神經(jīng)核團(tuán)不同時(shí)期發(fā)作期慢性期北大醫(yī)院醫(yī)學(xué)影像科鈣化北大醫(yī)院醫(yī)學(xué)影像科MRA少見異常DWIADC↑血管源性水腫ADC↓細(xì)胞毒性水腫MRSNAA↓Lac北大醫(yī)院醫(yī)學(xué)影像科1.2660.8261.172

0.765北大醫(yī)院醫(yī)學(xué)影像科1.0820.8310.851北大醫(yī)院醫(yī)學(xué)影像科北大醫(yī)院醫(yī)學(xué)影像科北大醫(yī)院醫(yī)學(xué)影像科Fig.1MRIexamswererealizedatadmission(D0),at15days(D15)ofevolution,andforcontrol6(M6)and12monthslater.ConventionalFLAIRandDWIdataarerepresentedinFig.1.FLAIRandDWIsequencesarerepresentedattwolevels;thefirst2leftcolumnscorrespondingtoaviewatthetemporallevel,andthe2rightcolumnstotheoccipitallevel.RowsrepresentsuccessivelyMRIexamsrealizedatD0,D15,andM6(MRIsatM12werenotrepresentedastheyweresimilartoimagesobtained6monthsearlier).Atadmission,recentlefttemporallesionappearedwithahyperintensityonFLAIRsequence(1a),andADCswereheterogeneous;elevatedinanteriorlocalization,anddiminishedinposteriorregion(1b).TherewerenosignalabnormalitiesonFLAIRorDWIviewsintheoccipitalregions(2aand2b).AtD15,bilateraloccipitalFLAIRhyperintensitiesappeared(2c).ADCsincreasedintheseregions(2d),andbecamehomogeneouslyelevatedinthelefttemporallesion(1d).AtM6,FLAIRhyperintensitiesdiminishedinthetemporallesion,replacedwithgliosis(1e),anddisappearedintheoccipitalregion(2e).LesionregressionwasmoremarkedinthoseregionsofthetemporallobeinwhichADCswerepreviouslythemostelevated(whitearrow).FLAIRabnormalitiesdisappearedcompletelyinoccipitalregions(2e),andADCsreachednormalvalues(2f).北大醫(yī)院醫(yī)學(xué)影像科amildenergyfailureresultinginmoderatecellulardysfunction,responsibleforvasogenicedema(highADCs)asevereenergyfailureresultinginanirreversiblecellularfailure,withcytotoxicedema(lowADCs).北大醫(yī)院醫(yī)學(xué)影像科36歲，女，急性聽覺失認(rèn)北大醫(yī)院醫(yī)學(xué)影像科急性期CBF↑北大醫(yī)院醫(yī)學(xué)影像科(a)MRAonday9.(b)ceT1WIonday23.男，8歲，卒中樣發(fā)