可复性后部脑病综合征MRI诊断及临床分析

【】　目的　探讨脑后部可逆性脑病综合征（posteriorreversibleencephalopathysyndrome，PRES）的临床及MRI表现，提高对PRES的认识。　方法　回顾性分析2007年1月-2010年12月期间5例PRES患者的MRI资料并进行追踪随访。5例PRES患者中男1例，女4例，肾性高血压及产后子痫各1例、妊娠高血压3例。5例均行MRI多序列平扫检查及弥散加权成像（diffusionweightedimaging，DWI），其中4例同时行磁共振血管造影（magneticresonanceangiography，MRA），2例行MRI增强检查。　结果　5例发病时均有高血压，以突发头痛、子痫或癫痫发作、意识障碍及视觉障碍为临床特点，及时正确治疗后症状于3~5d左右消失，1例遗留肢体功能障碍。MRI显示5例多发病灶主要位于双侧顶枕叶皮质下白质内，额叶及颞叶后部各2例，两侧小脑及脑干1例，皮质受累2例，病变呈长T1、长T2信号、液体衰减反转恢复序列呈高信号，5例患者病灶DWI图呈高或等信号，表观弥散系数（apparentdiffusioncoefficient，ADC）图呈略高信号；1例顶叶及1例基底节区部分病灶DWI图呈高信号，ADC图呈低信号，提示弥散受限。2例增强无强化，脑膜呈线状强化。随访MRI显示3例病灶完全消失。1例左侧基底节区部分病灶发展为脑梗死。　结论　PRES是一种临床-影像综合征，正确认识这一综合征对其早期诊断和治疗具有非常重要的意义。MRI能够提供较为可靠明确的诊断，其扩散成像对判断PRES预后亦很有价值。【Abstract】　Objective　ToinvestigatetheclinicalfeaturesandMRImanifestationsofpatientswithposteriorreversibleencephalopathysyndrome(PRES),inordertoimproveitsrecognition.　Methods　FromJanuary2007toDecember2010,MRIdataof5patientswithPRESwereretrospectivelyanalyzedandthepatientswerefollowedup.Amongthem,onewasmaleandfourwerefemale.Therewereonecaseofpostpartumeclampsia,oneofrenalhypertention,and3ofpregnancy-inducedhypertension.AllthefivepatientswereexaminedbyMRIdiffusionweightedimaging(DWI),amongwhomfourunderwentadditionalmagneticresonanceangiography(MRA)andoneunderwentenhancedMRI.　Results　AllthefivepatientswithPREShadhypertensionandtheirclinicalsymptomswerecharacterizedbysuddenoccurrenceofheadache,eclampsiaorseizureofepilepsy,alteredmentalstatus,andvisualdisturbances.Clinicalsymptomsvanishedabout3-5daysafterpromptandappropriatetreatmentexceptonecaseofresidualbodyfunctionfailure.MRIscanningdemonstratedmultifocalsubcorticalwhitelesionsinbilateralparieto-occipitallobesinfivepatients,inbilateralfrontallobesintwopatients,inbilateralposttemporallobesintwopatients,inbilateralcerebelluminonepatient,andinbilateralbrainsteminonepatient,andcorticalinvolvementoccurredinonepatient.Lesionsappearedashyperintensesignalsonfluidattenuatedinversionrecovery(FLAIR)andT2-weightedimages,hypointensesignalsonT1-weightedimages,normalorincreasedintensityonDWI,andmildhypointensityonapparentdiffusioncoefficient(ADC)maps.SomelesionsinparietallobesorbasalgangliashowedhyperintensityonDWIandisointensityonADCmaps.Thelesionsintwopatientsappearedunenhancedwithgadoliniumenhancementandthemeningesassumedthelinearstrengthening.Follow-upMRIshowedthatfociinthreepatientsvanishedcompletely,andthefocusintheleftbasalgangliainonepatientdevelopedintocerebralinfarction.　Conclusions　PRESisaclinical-neuroradiologicaltransientcondition.Correctlyunderstandingthissyndromeismeaningfulforitsearlydiagnosis.MRIcanprovideamorereliablediagnosis,andi