脑动静脉畸形大学12.pptx
Incidencen0.52%at autopsynSlight male preponderance(1.09 to 1.94)nCongenital lesions(although rarely familial)第1页/共42页EmbryologynFirst half of third week of gestationepiblastic cells migrate to form mesodermmesodermal cells differentiate to arterial and venous vessels on the surface of the embryonic nervous system第2页/共42页EmbryologynFirst half of third week of gestationepiblastic cells migrate to form mesodermmesodermal cells differentaite to arterial and venous vessels on the surface of the embryonic nervous systemnSeventh gestational weekvessels sprout branches&penetrate developing brainreach the gray-white interface,either loop back to pial surface or traverse entire neural tube,thus epicerebral&transcerebral circneventually connect arterial and venous systems by around the twelfth week 第3页/共42页Pathology&Pathophysiologynabsence of normal capillary system第4页/共42页Pathology&Pathophysiologynabsence of normal capillary systemnusual function displaced第5页/共42页Pathology&Pathophysiologynabsence of normal capillary systemnusual function displacednasymptomatic at birth第6页/共42页Pathology&Pathophysiologynabsence of normal capillary systemnusual function displacednasymptomatic at birthnvessels change with timenmay develop aneurysms第7页/共42页nparenchymal changes within and around the lesionPathology&Pathophysiologynabsence of normal capillary systemnusual function displacednasymptomatic at birthnvessels change with timenmay develop aneurysms第8页/共42页nparenchymal changes within and around the lesionnsite frequency is proportional to brain volumePathology&Pathophysiologynabsence of normal capillary systemnusual function displacednasymptomatic at birthnvessels change with timenmay develop aneurysms第9页/共42页Clinical presentationn95%have symptoms by age of 70 years第10页/共42页Clinical presentationn95%have symptoms by age of 70 yearsnpeak presentation second to fourth decade第11页/共42页Clinical presentationn95%have symptoms by age of 70 yearsnpeak presentation second to fourth decadehigh output failure,neonate,vein of Galenhydrocephalus,first decadeheadache,hemorrhage,seizures,2nd&3rd第12页/共42页Clinical presentationnfactors contributing to symptomsvessel walls,flow and pressures第13页/共42页Clinical presentationnfactors contributing to symptomsvessel walls,flow and pressuresenlargement and encroachment第14页/共42页Clinical presentationnfactors contributing to symptomsvessel walls,flow and pressuresenlargement and encroachmentdural sinuses第15页/共42页Clinical presentationnfactors contributing to symptomsvessel walls,flow and pressuresenlargement and encroachmentdural sinusesischaemia第16页/共42页Clinical presentationnfactors contributing to symptomsvessel walls,flow and pressuresenlargement and encroachmentdural sinusesischaemiacardiac output第17页/共42页Clinical presentation第18页/共42页HemorrhagenAVMrupture not a function of sizenAneurysmrupture related to aneurysm size第19页/共42页HemorrhagenAVMrupture not a function of sizeno marked increase with exercise,pregnancy,traumanAneurysmrupture related to aneurysm sizeincrease with trauma exercise,end pregnancy第20页/共42页HemorrhagenAVMrupture not a function of sizeno marked increase with exercise,pregnancy,traumaarteriovenous,therefore less severenAneurysmrupture related to aneurysm sizeincrease with trauma exercise,end pregnancyarterial,therefore more severe第21页/共42页HemorrhagenAVMrupture not a function of sizeno marked increase with exercise,pregnancy,traumaarteriovenous,therefore less severemortality 6 to 13.6%nAneurysmrupture related to aneurysm sizeincrease with trauma exercise,end pregnancyarterial,therefore more severemortality 30-50%第22页/共42页HemorrhagenAVMrupture not a function of sizeno marked increase with exercise,pregnancy,traumaarteriovenous,therefore less severemortality 6 to 13.6%lower rebleed mortality rate(1%)nAneurysmrupture related to aneurysm sizeincrease with trauma exercise,end pregnancyarterial,therefore more severemortality 30-50%higher rebleed mortality rate(13%)第23页/共42页HemorrhagenAVMrupture not a function of sizeno marked increase with exercise,pregnancy,traumaarteriovenous,therefore less severemortality 6 to 13.6%lower rebleed mortality rate(1%)vasospasm rarenAneurysmrupture related to aneurysm sizeincrease with trauma exercise,end pregnancyarterial,therefore more severemortality 30-50%higher rebleed mortality rate(13%)vasospasm common第24页/共42页Hemorrhage-AVMnNonetheless,risk of major,incapacitating,or fatal hemorrhage in untreated lesion is 40 to 50%第25页/共42页Hemorrhage-AVMnNonetheless,risk of major,incapacitating,or fatal hemorrhage in untreated lesion is 40 to 50%nYearly risk of initial hemorrhage 3%nRebleed in first subsequent year 6-18%,reducing to 3%again thereafternPediatric prognosis worse than adult 第26页/共42页Spetzler&Martin Grading SystemCriteriaScoreSize of Nidus Small(6cm)3Eloquence of Adjacent Brain No0Yes1Deep Vascular Component No0Yes1第27页/共42页Treatment OptionsHSurgical Resection第28页/共42页Treatment OptionsHSurgical ResectionHEndovascular Embolisation第29页/共42页Treatment OptionsHSurgical ResectionHEndovascular EmbolisationHStereotatic Radiosurgery第30页/共42页Treatment OptionsHSurgical ResectionHEndovascular EmbolisationHStereotatic RadiosurgeryHMultimodal Therapy第31页/共42页Treatment OptionsHSurgical ResectionHEndovascular EmbolisationHStereotatic RadiosurgeryHMultimodal TherapyHConservative Management第32页/共42页Normal Perfusion Pressure Breakthrough TheoryR.F.Spetzler et al第33页/共42页Normal perfusion pressure breakthrough theoryLoss of autoregulation and carbon dioxide reactivity in presence of large arteriovenous malformation.第34页/共42页Normal perfusion pressure breakthrough theoryLoss of autoregulation and carbon dioxide reactivity in presence of large arteriovenous malformation.Normal hemispheric vessels are chronically maximally dilated to attempt to divert flow from the AVM第35页/共42页Normal perfusion pressure breakthrough theoryLoss of autoregulation and carbon dioxide reactivity in presence of large arteriovenous malformation.Normal hemispheric vessels are chronically maximally dilated to attempt to divert flow from the AVMObliteration of the AVM diverts all flow to these maximally dilated vessels which have lost their normal control mechanisms第36页/共42页Normal perfusion pressure breakthrough theoryLoss of autoregulation and carbon dioxide reactivity in presence of large arteriovenous malformation.Normal hemispheric vessels are chronically maximally dilated to attempt to divert flow from the AVMObliteration of the AVM diverts all flow to these maximally dilated vessels which have lost their normal control mechanismsResults in loss of protection of the capillary bed,with edema and hemorrhage第37页/共42页nArterial inflowMathematical Models第38页/共42页nArterial inflownNidusMathematical Models第39页/共42页nArterial inflownNidusnVenous OutflowMathematical Models第40页/共42页Anaesthesia Technique第41页/共42页感谢您的观看！第42页/共42页
