Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0851184 (thinning)
 11,252 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Moyamoya formations at the base of the brain are not congenital vascular malformations but represent collateral pathways associated with chronic progressive stenosis of the carotid fork. The authors have studied 44 personal cases, 18 children under 15 years of age, and 26 adults. In children the Moyamoya vessels change through six stages: (1) carotid fork stenosis; (2) progressive carotid stenosis with initial Moyamoya collaterals and dilatations of cerebral arteries; (3) dilatation of Moyamoya collaterals and disappearance of anterior and middle cerebral arteries; (4) thinning of Moyamoya; (5) contraction of Moyamoya and disappearance of posterior cerebral arteries; (6) intracerebral vessels perfused from the external carotid and/or vertebrae. These six stages are not observed in adults. Bilateral cervical perivascular sympathectomy (PVS) was performed in 9 children and superior cervical ganglionectomy (SCG) was added unilaterally in 4 and bilaterally in 3 cases. Angiographic follow-up studies were carried out 1-7 years following surgery. Improvement was observed in most of the cases examined within the first 2 months after surgery. This was not the case in arteriograms performed more than 6 months postoperatively. It would seem that PVS and SCG can improve the progress of Moyamoya vessels but only for a short period of time. Clinical symptoms, however, seem to continue improving over a long period of time. Cerebral blood flow improved 5 weeks following surgery in a 13-year-old boy.
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PMID:An attempt to treat cerebrovascular 'Moyamoya' disease in children. 118 60

Moyamoya disease was originally defined as a characteristic syndrome of recurrent headaches, occlusion of the distal internal carotid arteries and the foggy (moyamoya) clusters of collateral vessels at the base of the brain as demonstrated by cerebral angiography. The etiology is unknown and pathobiology is poorly understood. We examined the intracranial arteries in 3 patients to demonstrate characteristic changes and to obtain a better understanding of the basis mechanisms of the disease. Controls were obtained from 3 normotensive patients who died as a result of cancer. Occluded internal carotid arteries were characterized by severe thickening of the intima with a dense luminal array of smooth muscle cells, a deeper less cellular zone, pronounced tortuosity of the internal elastica and thinning of the media. Collateral vessels were arterial in structure and were affected by similar proliferative changes in the intima, thinning of the media, and contorted internal elastica. Stainable lipids were not part of the typical components. Severe contortion of the internal elastica, medial damage and intimal proliferation may result from recurrent and sustained spasticity of the cerebral arteries. The distal lenticulostriate arteries showed severe medial damage similar to what is termed as a moth-eaten change in hypertensive patients dying of massive cerebral hemorrhage.
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PMID:Ultrastructural studies of cerebral arteries and collateral vessels in moyamoya disease. 646 67

Cerebral perfusion was examined in various types of occlusive disease by computed tomographic CBF method. The method utilized has several advantages over conventional studies using isotope, providing high resolution images in a direct relation to CT anatomy. Ten representative cases were presented from 25 consecutive cases of occlusive disease studied by this method. The method included inhalation of 40 to 60% xenon with serial CT scanning for 25 min. K (build-up rate), lambda (partition coefficient) and CBF values were calculated from HU for each pixel and Xe in expired air, based on Fick's principle, and displayed on CRT as K-, lambda- and CBF-map separately. CBF for gray matter of normal control was 82 +/- 11 ml/100 gm/min and that for white matter was 24 +/- 5 ml/100 gm/min. The ischemic threshold for gray matter appeared to be approximately 20 ml/100 gm/min, as blood flow in focus of complete infarction was below this level. Blood flow between 20-30 ml/100 gm/min caused some change on CT, such as localized atrophy, cortical thinning, loss of distinction between gray and white matter and decreased or increased density, which were considered to be compatible with pathological changes of laminar necrosis or gliosis with neuronal loss. In a case with occlusion of middle cerebral artery with subsequent recanalization, causing hemorrhagic infarct, hyperemia was observed in the infarcted cortex that was enhanced by iodine. Periventricular lucency observed in two cases, where blood flow was decreased below threshold, could be classified as "watershed infarction" mainly involving white matter. In moyamoya disease, blood flow in the anterior circulation was decreased near ischemic level, whereas that in basal ganglia and territory of posterior cerebral artery was fairly preserved, which was compatible with general angiographic finding of this disease.
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PMID:[Tomographic analysis of CBF in cerebral infarction]. 662 81

An 18 year old girl with typical clinical features of Williams syndrome suddenly died of intracerebral hemorrhage due to moyamoya disease. Autopsy revealed vascular abnormalities, such as supravalvular aortic stenosis (SAS) and an abnormal complicated cerebrovascular network in the cerebral arteries. The arterial wall of the SAS lesion consisted of thickened medial tissue showing elastic disorganization with prominence of the smooth muscle cells. The narrowed vessels of the circle of Willis showed intimal thickening with an extremely wavy internal elastic lamina and marked thinning of the media. To our knowledge, this is the first report of moyamoya disease associated with Williams syndrome.
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PMID:An autopsied case of Williams syndrome complicated by moyamoya disease. 846 May 48

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disease with unknown etiology. Recent genetic studies have identified RNF213 as an important susceptibility gene for MMD. To evaluate the role of RNF213 in vascular remodeling, RNF213 knockout mice (RNF213-/-) and their wild-type littermates (WT) were subjected to common carotid artery ligation to induce vascular hyperplasia. We examined the vascular expression of matrix metalloproteinase (MMP)-9, known to be increased in MMD. MMP-9 expression was significantly higher in RNF213-/- mice than in wild-type mice 1 and 7 days after common carotid artery ligation. The vascular wall was significantly thinner in RNF213-/- mice at 14 days. The increased vascular expression of MMP-9 and subsequent vascular wall thinning in RNF213-/- mice could reflect the early characteristic of MMD, consistent with the recently proposed constrictive remodeling theory.
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PMID:Increased vascular MMP-9 in mice lacking RNF213: moyamoya disease susceptibility gene. 2538 61

Moyamoya disease (MMD) is a rare cerebrovascular disease with an unknown etiology and is characterized by intrinsic fragility in the intracranial vascular walls such as the affected internal elastic lamina and thinning medial layer. The association of MMD with intracranial arterial dissection is extremely rare, whereas that with basilar artery dissection (BAD) has not been reported previously. A 46-year-old woman developed brain stem infarction due to BAD 4 years after successful bilateral superficial temporal artery-middle cerebral artery anastomosis with indirect pial synangiosis for ischemic-onset MMD. She presented with sudden occipitalgia and subsequently developed transient dysarthria and mild hemiparesis. Although a transient ischemic attack was initially suspected, her condition deteriorated in a manner that was consistent with left hemiplegia with severe dysarthria. Magnetic resonance (MR) imaging revealed brain stem infarction, and MR angiography delineated a double-lumen sign in the basilar artery, indicating BAD. She was treated conservatively and brain stem infarction did not expand. One year after the onset of brain stem infarction, her activity of daily living is still dependent (modified Rankin Scale of 4), and there were no morphological changes associated with BAD or recurrent cerebrovascular events during the follow-up period. The association of MMD with BAD is extremely rare. While considering the common underlying pathology such as an affected internal elastic lamina and fragile medial layer, the occurrence of BAD in a patient with MMD in a stable hemodynamic state is apparently unique.
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PMID:Brain Stem Infarction Due to Basilar Artery Dissection in a Patient with Moyamoya Disease Four Years after Successful Bilateral Revascularization Surgeries. 2706 74

The authors present the first case of central retinal artery occlusion (CRAO) resulting from moyamoya syndrome secondary to Southampton hemoglobinopathy. A 12-year-old Hispanic girl with a history of Southampton hemoglobinopathy with moyamoya syndrome presented with amaurosis fugax in her left eye that resolved within hours except for an inferior paracentral scotoma. She had left ophthalmic artery occlusion on magnetic resonance angiogram. Seven months later, spectral-domain optical coherence tomography showed diffuse inner retinal thinning. She was diagnosed with transient CRAO. The authors conclude that CRAO can result from moyamoya syndrome secondary to an underlying hemoglobinopathy. Multimodal imaging demonstrated residual inner retinal injury despite reperfusion. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e166-e170.].
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PMID:CRAO in Moyamoya Syndrome Associated With Southampton Hemoglobinopathy. 3110 Jan 71

Moyamoya disease (MMD) is a rare cerebro-occlusive disease with unknown etiology that can cause both ischemic and hemorrhagic stroke. MMD is characterized by progressive stenosis of the terminal internal carotid artery (ICA) and development of basal brain collaterals. Early-stage MMD is known to cause hemodynamic insufficiency despite mild or moderate stenosis of the intracranial arteries, but the exact mechanism underlying this pathophysiological condition is undetermined. We used high-resolution Large Eddy Simulations to investigate multiple complex hemodynamic phenomena that led to cerebral ischemia in five patients with early-stage MMD. The effects of transitional flow, coherent flow structures and blood shear-thinning properties through regions of tortuous and stenosed arteries were explored and linked to symptomatology. It is evidently shown that in some cases complex vortex structures, such as Rankine-type vortices, redirects blood flow away from some arteries causing significant reduction in blood flow. Moreover, partial blood hammer (PBH) phenomenon was detected in some cases and led to significant hemodynamic insufficiency. PBH events were attributed to the interaction between shear-thinning properties, transitional flow structures and loss of upstream pressure-velocity phase lag. We clearly show that the hemodynamic complexities in early-stage MMD could induce ischemia and explain the non-responsiveness to antiplatelet therapy.
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PMID:The hemodynamic complexities underlying transient ischemic attacks in early-stage Moyamoya disease: an exploratory CFD study. 3226 53