Moyamoya

Introduction: Moyamoya disease (MD) is a progressive, occlusive disease of the arteries of
the anterior cerebral circulation that may cause ischaemia or haemorrhage. Patient management
aims to prevent new cerebrovascular events through surgical revascularisation and/or
pharmacological treatment.
Methods: We studied a series of 17 patients with MD (n = 14) or moyamoya syndrome (n = 3),
who were evaluated between January 1989 and December 2016; 11 patients were women and
6 were men. Thirteen patients had definitive MD (76%), one had unilateral MD (5.2%), and 3
had moyamoya syndrome (18%). The condition manifested as intraparenchymal haemorrhage
(in 35.2% of patients), brain ischaemia (29.4%), subarachnoid haemorrhage (17.6%), seizures
(11.7%), and headache with no associated haemorrhage (one patient).
Results: Ten patients (58.8%) underwent revascularisation and 7 (41.2%) received pharmacological
treatment. All patients were evaluated with the modified Rankin Scale (mRs) at admission
and at the last consultation; mRs scores were significantly lower in the group undergoing surgery
(P < .04). During follow-up, none of the patients undergoing revascularisation experienced
recurrences, whereas 2 patients receiving pharmacological treatment did experience a new
vascular event (one ischaemic and one haemorrhagic) (P < .05). No significant differences were
observed between the treatment outcomes of different revascularisation techniques.
Conclusions: Although our population has different demographic characteristics from those of
other non-Asian populations, ours is the largest published series of Hispanic individuals with
MD. Our results support the use of revascularisation procedures to improve these patients’
neurological status and to prevent new cerebrovascular events.
© 2018 Sociedad Espa˜nola de Neurología. Published by Elsevier España, S.L.U. This is an
open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/
by-nc-nd/4.0/).

Background: The pathogenesis of moyamoya disease (MMD) is still unknown. The detection of inflammatory molecules such as cytokines, chemokines and growth factors in MMD patients&#39; biological fluids supports the hypothesis that an abnormal angiogenesis is implicated in MMD pathogenesis. However, it is unclear whether these anomalies are the consequences of the disease or rather causal factors as well as these mechanisms remain insufficient to explain the pathophysiology of MMD. The presence of a family history in about 9-15% of Asian patients, the highly variable incidence rate between different ethnic and sex groups and the age of onset support the role of genetic factors in MMD pathogenesis. However, although some genetic loci have been associated with MMD, few of them have been replicated in independent series. Recently, RNF213 gene was shown to be strongly associated with MMD occurrence with a founder effect in East Asian patients. However, the mechanisms leading from RNF213 m...

Background: The pathogenesis of moyamoya disease (MMD) is still unknown. The detection of inflammatory molecules such as cytokines, chemokines and growth factors in MMD patients’ biological fluids supports the hypothesis thatan abnormal angiogenesis is implicated in MMD pathogenesis. However, it is unclear whether these anomalies are the consequences of the disease or rather causal factors as well as these mechanisms remain insufficient to explain the pathophysiology of MMD. The presence of a family history in about 9–15% of Asian patients, the highly variable incidence rate between different ethnic and sex groups and the age of onset support the role of genetic factors in MMD pathogenesis. However, although some genetic loci have been associated with MMD, few of them have been replicated in independent series. Recently, RNF213 gene was shown to be strongly associated with MMD occurrence with a founder effect in East Asian patients. However, the mechanisms leading from RNF213 mutations to MMD clinical features are still unknown. Summary: The research on pathogenic mechanism of MMD is in its infancy. MMD is probably a complex
and heterogeneous disorder, including different phenotypes and genotypes, in which more than a single factor is implicated. Key Message: Since the diagnosis of MMD is rapidly increasing worldwide, the development of more efficient stratifying risk systems, including both clinical but also biological drivers became imperative to improve our ability of predict prognosis and to develop mechanism-tailored interventions.

Background. Moyamoya disease (MMD) is a slowly progressing steno-occlusive cerebrovascular disease. The typical moyamoya vessels, which originate from an initial stenosis of the internal carotid, make reliable that increased and/or abnormalities of angiogenic, vasculogenic and arteriogenic processes are involved in the disease pathophysiology. Objective. Herein, we summarize the current knowledge on the most important signaling pathways involved in MMD vessel formation, particularly focusing on the expression of growth factors and function of endothelial progenitor cells (EPCs). Methods and Results. Higher plasma concentrations of vascular endothelial growth factor, matrix metalloproteinase, hepatocyte growth factor, and interleukin-1ß were reported in MMD patients. A specific higher level of basic fibroblast growth factor was also found in the cerebrospinal fluid of these patients. Finally, the number and the functionality of EPCs were found to be increased. In spite of these available data, the approaches and findings reported so far do not give an evident correlation between the expression levels of the aforementioned growth factors and MMD severity. Furthermore, the controversial results provided by studies on EPCs, do not permit us to understand the true involvement of these cells in MMD pathophysiology. Conclusion. Further studies have to be implemented in order to draw some novel insights into the contribution of processes regulating both the arterial stenosis and the excessive formation of collateral vessels. Integrated approaches, including functional assays and correlation between biological and clinical data, may extend our knowledge on the pathogenesis of MMD and find potential therapeutic targets.