Moyamoya disease&

Adult Moyamoya disease

Youmans chapter 207&356

Outline

• Introduction• Epidemiology• Pathophysiology and etiology• Clinical finding• Neuroimaging• Treatment

Introduction• Moyamoya disease (MDD)• Rare• Stenosis-occlusion of bilateral ICAs at their terminal

portion development peculiar moyamoya vascular at the base of brain

• Moyamoya syndrome : unilateral ICA occlusion• Moyamoya : distinctive finding on arteriography• Adult : cerebral hemorrhage• Children : cerebral ischemia, 50% in 10 years old• Etiology unknown

Introduction• 1957 Takeuchi and Shizimu

man, 29 Years old, visual disturbance since 10 Yrs, hemiconvulsive since 13 years oldangiogram : bilateral ICAs

• 1969 Suzuki and TakakuTerm Moyamoya (puff of smoke)

Epidemiology• Japan, Asian, Non-asian

Association condition in pedriatic

Pathophysiology and etiology• Not arteriosclerotic or inflammatory change• diagnosis of MMD

– fibrocellular thickening of the intima– irregular disruption of the internal elastic lamina– attenuation of the media

• Pluripotent peptides and their receptors– basic fibroblast growth factor,transforming growth

factor-,hepatocyte growth factor increased– angiogenesis and intimal hyperplasia

• G internal hyperplasia• I internal elastic

lamina disruption• H,J : control

Clinical finding

Clinical finding• Infarction : watershed and PCA territory

– Frontal and temporal lobe– Hemiparesis, dysarthria, aphasia, cognitive impairment– Seizure– Pedriatric : mistaken for psychiatric illness or developmental

delay – Pedriatric : TIA parcipitate by hyperventilation with

crying,exertion,dehydration,cold or fever – Pedriatic with cerebral ischemia should be consider as a

possible Moyamota patient until prove other wise

Clinical finding• Hemorrhage : intraventricular, periventricular, intraparenchymal

– Hall mark of adult MMD– rupture of dilated and stressed perforating arteries containing

microaneurysms,– fibrinoid necrosis of the arterial wall in the basal ganglia– rupture of microaneurysms in the periventricular region, especially

around the superolateral wall of the lateral ventricles

• Headache in pedriatic• Pregnancy and delivery may increase risk for ischemic or

hemorrhagic stroke in female patients

• .

Clinical finding• Saccular aneurysm

• 60% around the circle of Willis, mainly at the vertebrobasilar territory

• 20% in peripheral arteries, such as the posterior and anterior choroidal arteries

• 20% in the abnormal moyamoya vasculature as mentioned earlier

• May disappear or need to surgically of repeated bleeding

Neuroimaging• Cerebral angiography

– Plan of surgery

• Classification of Suzuki and Takaku– 1) narrowing of the carotid fork– (2) initiation of the moyamoya– (3) intensification of the moyamoya– (4) minimization of the moyamoya– (5) reduction of the moyamoya– (6) disappearance of the moyamoya

• Basal moyamoya– Basal ganglia– Thalamus– Lenticulostriate– Anterior choroidal artery– Posterior choroidal artery

• Ethmoidal moyamoya– Anterior or posterior

ethmoidal a form Opthalmic artery

• Vault moyamoya– Dural arteries

• MRI & MRA noninvasive

• A-C : 1.5 T MRA• B-D : 3 T MRA

Neuroimaging

T1 : sensitive for detect basal moyamoyaT2 : detect microbleeding 15-44%

Ivy sign : Leptomeningeal metastases, subarachnoid hemorrhage (SAH), meningitis, increased inspired oxygen

-Xenon-enhanced computed tomography, single-photon emission computed tomography, and positron emission tomography (PET) can be used to measure regional CBF and metabolic distribution- a : impair hemodynamic reserve on loading with acetazolamide- b : postoperative improve of ACA and MCA

Treatment in adult• Non-operative management

– ASA– Calcium antagonist : empirical headache– Steroid : involuntary movement or at the time of frequent TIA

• Surgical management : augment impair CBF– Direct revascularization with microvascular extracranial to

intracranial(EC-IC) by pass,prefer to adult– Indirect revascularization without microvascular anastomotic

procedure,prefer to children

Direct revascularization procesure using a microvascualr technique for STA-MCA bypass

• 1967 Donaghy and Yasargil• Donor vessel, locate by dopple sonography

– Parital, less often frontal branch– 1 mm in diameter, 8-10 cm, free preparation

• Craniotomy– Small, 2.5-3 cm in diameter– Center about 6 cm above EAM(end of sylvian fissure )

• MCA– Posterior temporal,posterior parietal a.– 10-0,11-0 8-10 interrupted

• Advantage– Selective supplying territories of ischemia

Indirect bypass techniques

• Mobilizing vascularized tissue supplied by the ECA and placing it in contact to the brain

• Encephalomyosynangiosis(EMS)– 1970, Karasawa– Inappropriate cortical branch of MCA,especially children– Gradual revascularization– Implanting temporalis m on brain surface, secure to dura edge

Indirect bypass techniques• Encephaloduroarteriosynangiosis(EDAS)

– 1979, Matsushima– Prefer technique– Parietal brach of STA with preservation of vascular flow– Dissected STA is laid onto the cortical surface after having

opened the arachnoidea

Perioperative management• Pt in stable clinical condition without frequent ischemic

episode• Sufficient hydration to patient• Normocapnia during surgery• Preoperative evaluation of hemodynamic dysfunction

with acetazolamide with caution and surgery perform(after 48 hrs)

Prognosis• 75-80%, benign course interm of life, with or without

surgical• After revascularization

– free of TIA and ischemic stroke– Rebleeding during FU 30-65%

• MRI and MRA detect asymptomatic pt• Unilateral MDD

– 7-27% progress to bilateral

Moyamoya disease

• What is MMD?• What is most common symptom of MMD?• What is pathology of MMD vessel?• How to augmentation by surgical method for

MMD?• How to preparation patient before operation?