脑动静脉畸形大学教学课件

1、CEREBRALARTERIOVENOUS MALFORMATIONSAVM: a TLA for the CNSIncidence0.52% at autopsySlight male preponderance (1.09 to 1.94)Congenital lesions (although rarely familial)EmbryologyFirst half of third week of gestationepiblastic cells migrate to form mesodermmesodermal cells differentiate to arterial an

2、d venous vessels on the surface of the embryonic nervous systemEmbryologyFirst 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 systemSeventh gestational weekvessels sprout br

3、anches & 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 Pathology & Pathophysiologyabsence of normal capillary s

4、ystemPathology & Pathophysiologyabsence of normal capillary systemusual function displacedPathology & Pathophysiologyabsence of normal capillary systemusual function displacedasymptomatic at birthPathology & Pathophysiologyabsence of normal capillary systemusual function displacedasymptomatic at bir

5、thvessels change with timemay develop aneurysmsparenchymal changes within and around the lesionPathology & Pathophysiologyabsence of normal capillary systemusual function displacedasymptomatic at birthvessels change with timemay develop aneurysmsparenchymal changes within and around the lesionsite f

6、requency is proportional to brain volumePathology & Pathophysiologyabsence of normal capillary systemusual function displacedasymptomatic at birthvessels change with timemay develop aneurysmsClinical presentation95% have symptoms by age of 70 yearsClinical presentation95% have symptoms by age of 70

7、yearspeak presentation second to fourth decadeClinical presentation95% have symptoms by age of 70 yearspeak presentation second to fourth decadehigh output failure, neonate, vein of Galenhydrocephalus, first decadeheadache, hemorrhage, seizures, 2nd & 3rdClinical presentationfactors contributing to

8、symptomsvessel walls, flow and pressuresClinical presentationfactors contributing to symptomsvessel walls, flow and pressuresenlargement and encroachmentClinical presentationfactors contributing to symptomsvessel walls, flow and pressuresenlargement and encroachmentdural sinusesClinical presentation

9、factors contributing to symptomsvessel walls, flow and pressuresenlargement and encroachmentdural sinusesischaemiaClinical presentationfactors contributing to symptomsvessel walls, flow and pressuresenlargement and encroachmentdural sinusesischaemiacardiac outputClinical presentationHemorrhageAVMrup

10、ture not a function of sizeAneurysmrupture related to aneurysm sizeHemorrhageAVMrupture not a function of sizeno marked increase with exercise, pregnancy, traumaAneurysmrupture related to aneurysm sizeincrease with trauma exercise, end pregnancyHemorrhageAVMrupture not a function of sizeno marked in

11、crease with exercise, pregnancy, traumaarteriovenous, therefore less severeAneurysmrupture related to aneurysm sizeincrease with trauma exercise, end pregnancyarterial, therefore more severeHemorrhageAVMrupture not a function of sizeno marked increase with exercise, pregnancy, traumaarteriovenous, t

12、herefore less severemortality 6 to 13.6%Aneurysmrupture related to aneurysm sizeincrease with trauma exercise, end pregnancyarterial, therefore more severemortality 30-50%HemorrhageAVMrupture not a function of sizeno marked increase with exercise, pregnancy, traumaarteriovenous, therefore less sever

13、emortality 6 to 13.6%lower rebleed mortality rate (1%)Aneurysmrupture related to aneurysm sizeincrease with trauma exercise, end pregnancyarterial, therefore more severemortality 30-50%higher rebleed mortality rate (13%)HemorrhageAVMrupture not a function of sizeno marked increase with exercise, pre

14、gnancy, traumaarteriovenous, therefore less severemortality 6 to 13.6%lower rebleed mortality rate (1%)vasospasm rareAneurysmrupture related to aneurysm sizeincrease with trauma exercise, end pregnancyarterial, therefore more severemortality 30-50%higher rebleed mortality rate (13%)vasospasm commonH

15、emorrhage - AVMNonetheless, risk of major, incapacitating, or fatal hemorrhage in untreated lesion is 40 to 50% Hemorrhage - AVMNonetheless, risk of major, incapacitating, or fatal hemorrhage in untreated lesion is 40 to 50%Yearly risk of initial hemorrhage 3%Rebleed in first subsequent year 6-18%,

16、reducing to 3% again thereafterPediatric prognosis worse than adult Spetzler & Martin Grading SystemCriteriaScoreSize of Nidus Small (6cm)3Eloquence of Adjacent Brain No0Yes1Deep Vascular Component No0Yes1Treatment OptionsSurgical ResectionTreatment OptionsSurgical ResectionEndovascular Embolisation

17、Treatment OptionsSurgical ResectionEndovascular EmbolisationStereotatic RadiosurgeryTreatment OptionsSurgical ResectionEndovascular EmbolisationStereotatic RadiosurgeryMultimodal TherapyTreatment OptionsSurgical ResectionEndovascular EmbolisationStereotatic RadiosurgeryMultimodal TherapyConservative

18、 ManagementNormal Perfusion Pressure Breakthrough TheoryR.F. Spetzler et alNormal perfusion pressure breakthrough theoryLoss of autoregulation and carbon dioxide reactivity in presence of large arteriovenous malformation.Normal perfusion pressure breakthrough theoryLoss of autoregulation and carbon

19、dioxide reactivity in presence of large arteriovenous malformation.Normal hemispheric vessels are chronically maximally dilated to attempt to divert flow from the AVMNormal 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 dil