Moyamoya disease in adults: the role of cerebral revascularization

Surgical revascularization as a procedure to prevent neurological complications in children with moyamoya syndrome associated with neurofibromatosis I: a single institution case series

BACKGROUND

The optimal timing and surgical approach for surgical revascularization in patients with moyamoya syndrome (MMS) associated with neurofibromatosis type I (NF1) remain so far elusive. We aimed to compare the long-term clinical, radiological, and cognitive effects of different revascularization procedures in a pediatric cohort of NF1-associated MMS.

METHODS

We reviewed the clinical, radiological, and surgical data of 26 patients with NF1-associated MMS diagnosed at our institution between 2012 and 2022, at the clinical onset and last follow-up.

RESULTS

Indirect bypasses were performed in 12/26 patients (57.1%), while combined direct and indirect procedures in 9/26 subjects (42.9%); 5 patients did not undergo surgery. Through logistic regression analysis, pathological Wechsler Intelligence Scale for Children (WISC) at onset was found to be associated with symptom improvement at 1-year follow up (p = 0.006). No significant differences were found in long-term neurocognitive outcome and stroke rate in patients receiving combined or indirect bypass (p > 0.05).

CONCLUSIONS

Currently, whether combined or indirect bypass should be considered the treatment of choice in pediatric patients with NF1-associated MMS remains unclear, as well as the optimal time approach. In our series, no significant differences were found in long-term neurocognitive outcome and stroke rate between patients treated with either of these two approaches. Clinical evidence supports the crucial role of early diagnosis and surgical revascularization in subjects with MMS-associated NF1, even in case of mildly symptomatic vasculopathy. This allows to achieve a good long-term outcome with improved intellectual function and prevention of stroke and seizure in these patients.

[Moyamoya disease in adults: treatment methods in modern era]

Moyamoya angiopathy is a chronic progressive cerebrovascular disease characterized by stenosis and occlusion of the distal segments of the internal carotid arteries and/or proximal segments of the middle and anterior cerebral arteries, with a gradual compensatory restructuring of the cerebral circulation to the system of the external carotid arteries. Today, the main treatment method for Moyamoya angiopathy is surgical revascularization of the brain. A search and analysis of publications on the treatment of adult patients with Moyamoya angiopathy was carried out in the PubMed and Medscape databases over the past 10 years. We present a case of an adult female patient with a hemorrhagic form of Moyamoya angiopathy stage IV according to J. Suzuki, who underwent staged combined revascularization of both cerebral hemispheres. Surgical revascularization included the creation of a low-flow extra-intracranial shunt combined with a combination of indirect synangiosis. The combination of direct and indirect methods of surgical revascularization enables to achieve the development of an extensive network of collaterals and fully compensate for cerebral circulatory disorders both in the early and late postoperative periods, which is confirmed by instrumental diagnostic data. Combined revascularization is the most effective modern method of treating patients with Moyamoya angiopathy due to the complementary influence of direct and indirect components of revascularization.

Perioperative Management of Pediatric Patients with Moyamoya Arteriopathy

Pediatric patients with moyamoya arteriopathy are at high risk for developing new onset transient or permanent neurologic deficits secondary to cerebral hypoperfusion, particularly in the perioperative period. It is therefore essential to carefully manage these patients in a multidisciplinary, coordinated effort to reduce the risk of new permanent neurologic deficits. However, little has been published on perioperative management of pediatric patients with moyamoya, particularly in the early postoperative period during intensive care unit admission. Our pediatric neurocritical care team sought to create a multidisciplinary periprocedural evidence- and consensus-based care pathway for high-risk pediatric patients with moyamoya arteriopathy undergoing anesthesia for any reason to decrease the incidence of periprocedural stroke or transient ischemic attack (TIA). We reviewed the literature to identify risk factors associated with perioperative stroke or TIA among patients with moyamoya and to gather data supporting specific perioperative management strategies. A multidisciplinary team from pediatric anesthesia, neurocritical care, nursing, child life, neurosurgery, interventional neuroradiology, neurology, and hematology created a care pathway for children with moyamoya undergoing anesthesia, classifying them as either high or standard risk, and applying an individualized perioperative management plan to high-risk patients. The incidence of neurologic sequelae before and after pathway implementation will be compared in future studies.

Designing a flow-controlled STA-MCA anastomosis based on the Hagen-Poiseuille law for preventing postoperative hyperperfusion in adult moyamoya disease

Background

Technical improvements for preventing postoperative symptomatic cerebral hyperperfusion (CHP) during superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis for moyamoya disease (MMD) were seldom reported.

Objectives

The aim of this study was to investigate the significance of application of a novel flow-controlled concept which voluntarily reduces the hemodynamic difference between the donor and recipient arteries based on the Hagen-Poiseuille law when performing direct anastomoses of recipient parasylvian cortical arteries (PSCAs) with anterograde hemodynamic sources from the MCA (M-PSCAs) in adult MMD.

Design

This was a retrospective observational study.

Methods

Direct anastomoses of recipient M-PSCAs were performed on 89 symptomatic hemispheres in 82 adult MMD patients in our hospital from January 2020 to June 2021. They were divided into the flow-controlled group (patients who received direct anastomosis under designed flow-controlled principles) and non-flow-controlled group (patients who received conventional direct anastomosis to obtain maximum flow). The patients' basic characteristics and incidence of postoperative CHP were compared between the two groups. Risk factors for occurrence of postoperative CHP were analyzed.

Results

Overall, 36 hemispheres were included in the non-flow-controlled group and 53 in flow-controlled group. The incidences of postoperative focal (22.6%) and symptomatic CHP (5.7%) in the flow-controlled group were significantly lower than those (focal, 52.8%; symptomatic, 25.0%) in the non-flow-controlled group (p = 0.003 and 0.009, respectively). Multivariate analysis revealed that the flow-controlled concept was significantly associated with the development of focal (p = 0.005) and symptomatic (p = 0.012) CHP.

Conclusion

The flow-controlled STA-MCA anastomosis can significantly decrease the incidence of postoperative CHP during direct anastomoses of recipient M-PSCAs in adult MMD.

Metabolism changes during direct revascularization in moyamoya disease: illustrative case

BACKGROUND

Cerebral revascularization is recommended for patients with moyamoya disease (MMD) with reduced cerebral perfusion reserve and recurrent or progressive ischemic events. The standard surgical treatment for these patients is a low-flow bypass with or without indirect revascularization. The use of intraoperative monitoring of the metabolic profile using analytes such as glucose, lactate, pyruvate, and glycerol has not yet been described during cerebral artery bypass surgery for MMD-induced chronic cerebral ischemia. The authors aimed to describe an illustrative case using intraoperative microdialysis and brain tissue oxygen partial pressure (PbtO2) probes in a patient with MMD during direct revascularization.

OBSERVATIONS

The patient's severe tissue hypoxia situation was confirmed by a PbtO2:partial pressure of oxygen (PaO2) ratio below 0.1 and anaerobic metabolism by a lactate:pyruvate ratio greater than 40. Following bypass, a rapid and sustained increase in PbtO2 up to normal values (PbtO2:PaO2 ratio between 0.1 and 0.35) and the normalization of cerebral energetic metabolism with a lactate/pyruvate ratio less than 20 was observed.

LESSONS

The results show a quick improvement of regional cerebral hemodynamics due to the direct anastomosis procedure, reducing the incidence of subsequent ischemic stroke in pediatric and adult patients immediately.

Intracranial Artery Morphology in Pediatric Moya Moya Disease and Moya Moya Syndrome

BACKGROUND

Moya Moya disease (MMD) and Moya Moya syndrome (MMS) are cerebrovascular disorders, which affect the internal carotid arteries (ICAs). Diagnosis and surveillance of MMD/MMS in children mostly rely on qualitative evaluation of vascular imaging, especially MR angiography (MRA).

OBJECTIVE

To quantitatively characterize arterial differences in pediatric patients with MMD/MMS compared with normal controls.

METHODS

MRA data sets from 17 presurgery MMD/MMS (10M/7F, mean age = 10.0 years) patients were retrospectively collected and compared with MRA data sets of 98 children with normal vessel morphology (49 male patients; mean age = 10.6 years). Using a level set segmentation method with anisotropic energy weights, the cerebral arteries were automatically extracted and used to compute the radius of the ICA, middle cerebral artery (MCA), anterior cerebral artery (ACA), posterior cerebral artery (PCA), and basilar artery (BA). Moreover, the density and the average radius of all arteries in the MCA, ACA, and PCA flow territories were quantified.

RESULTS

Statistical analysis revealed significant differences comparing children with MMD/MMS and those with normal vasculature (P < .001), whereas post hoc analyses identified significantly smaller radii of the ICA, MCA-M1, MCA-M2, and ACA (P < .001) in the MMD/MMS group. No significant differences were found for the radii of the PCA and BA or any artery density and average artery radius measurement in the flow territories (P > .05).

CONCLUSION

His study describes the results of an automatic approach for quantitative characterization of the cerebrovascular system in patients with MMD/MMS with promising preliminary results for quantitative surveillance in pediatric MMD/MMS management.

Pathophysiology of Vascular Stenosis and Remodeling in Moyamoya Disease

Moyamoya disease (MMD) and moyamoya syndrome (MMS) are progressive vascular pathologies unique to the cerebrovasculature that are important causes of stroke in both children and adults. The natural history of MMD is characterized by primary progressive stenosis of the supraclinoid internal carotid artery, followed by the formation of fragile collateral vascular networks. In MMS, stenosis and collateralization occur in patients with an associated disease or condition. The pathological features of the stenosis associated with MMD include neointimal hyperplasia, disruption of the internal elastic lamina, and medial attenuation, which ultimately lead to progressive decreases in both luminal and external arterial diameter. Several molecular pathways have been implicated in the pathophysiology of stenosis in MMD with functions in cellular proliferation and migration, extracellular matrix remodeling, apoptosis, and vascular inflammation. Importantly, several of these molecular pathways overlap with those known to contribute to diseases of systemic arterial stenosis, such as atherosclerosis and fibromuscular dysplasia (FMD). Despite these possible shared mechanisms of stenosis, the contrast of MMD with other stenotic pathologies highlights the central questions underlying its pathogenesis. These questions include why the stenosis that is associated with MMD occurs in such a specific and limited anatomic location and what process initiates this stenosis. Further investigation of these questions is critical to developing an understanding of MMD that may lead to disease-modifying medical therapies. This review may be of interest to scientists, neurosurgeons, and neurologists involved in both moyamoya research and treatment and provides a review of pathophysiologic processes relevant to diseases of arterial stenosis on a broader scale.

Actin R256 Mono-methylation Is a Conserved Post-translational Modification Involved in Transcription

Nuclear actin has been elusive due to the lack of knowledge about molecular mechanisms. From actin-containing chromatin remodeling complexes, we discovered an arginine mono-methylation mark on an evolutionarily conserved R256 residue of actin (R256me1). Actin R256 mutations in yeast affect nuclear functions and cause diseases in human. Interestingly, we show that an antibody specific for actin R256me1 preferentially stains nuclear actin over cytoplasmic actin in yeast, mouse, and human cells. We also show that actin R256me1 is regulated by protein arginine methyl transferase-5 (PRMT5) in HEK293 cells. A genome-wide survey of actin R256me1 mark provides a landscape for nuclear actin correlated with transcription. Further, gene expression and protein interaction studies uncover extensive correlations between actin R256me1 and active transcription. The discovery of actin R256me1 mark suggests a fundamental mechanism to distinguish nuclear actin from cytoplasmic actin through post-translational modification (PTM) and potentially implicates an actin PTM mark in transcription and human diseases.

Nuclear actin and actin PTMs are poorly understood. Kumar et al. discover a system of actin PTMs similar to histone PTMs, including a conserved mark on nuclear actin (R256me1) with potential implications for transcription and human diseases.

Characteristics of Moyamoya Disease in the Older Population: Is It Possible to Define a Typical Presentation and Optimal Therapeutical Management?

Whereas several studies have been so far presented about the surgical outcomes in terms of mortality and perioperative complications for elderly patients submitted to neurosurgical treatments, the management of elderly moyamoya patients is unclear. This review aims to explore the available data about the clinical manifestation, characteristics, and outcome after surgery of older patients with moyamoya arteriopathy (MA). We found only two articles strictly concerning elderly patients with MA. We have also evaluated other reported adult series of moyamoya patients, including elderly cases in their analysis. Patients with MA above 50 years old may be considered a peculiar subset in which patients are often presenting with ischemic symptoms and a higher Suzuki grade. Conservative treatment may be proposed in asymptomatic or stable cases due to their fragility and possible increase of post-operative complications, while the best surgical options in symptomatic cases are still under investigation, although we believe that a minimal invasive superficial temporal artery—middle cerebral artery bypass could be considered the treatment of choice for the immediate effect on brain perfusion with a limited rate of post-operative complications.

[Anatomical bases of brain revascularization: choosing an extra-intracranial bypass option]

Surgical brain revascularization is an important treatment for acute or chronic ischemia, intracranial aneurysms and skull base tumors. Individual anatomy of brain vessels should be clearly understood for this procedure. Variants of collateral cerebral blood flow in patients with cerebrovascular diseases depend on individual characteristics of circle of Willis and reserve mechanisms of collateral circulation. These anatomical variations require careful preoperative planning to choose the optimal revascularization option.

Moyamoya-like vasculopathy associated to MYH9-related thrombocytopenia manifested by multiple cerebral ischemic lesions: a case report

Background

Moyamoya-like vasculopathy (MMV) and myosin heavy chain 9-related platelet disorders (MYH9-RPDs) or macrothrombocitopenias are rare syndromes. Their association is even more infrequent.

Case presentation

A 29-year-old female with history of MYH9-RPD, presented to our department for episodes suggesting transient ischemic attacks. Based on the imaging studies that revealed multiple ischemic lesions and stenoses of both distal internal carotid arteries and the arteries of the circle of Willis, the diagnosis of MMV was established. The treatment with Verapamil was initiated, leading to symptom remission. Two months later, the patient presented one episode of dysarthria, followed by involuntary movements of the right upper limb, few days later. Long-term electroencephalogram monitoring depicted epileptiform abnormalities. Resolution of symptoms was obtained after increasing the dose of Verapamil, and initiating Levetiracetam.

Conclusions

This is an interesting case of a patient with two rare pathologies, who presented with cerebral ischemic strokes. To our knowledge there are few cases described in the literature presenting with cerebral hemorrhagic events but none of them with multiple cerebral ischemic lesions. As these cases are very rare, it is important to gather evidence regarding the best approach and treatment strategy.

Significance of Serum Angiopoietin-2 in Patients with Hemorrhage in Adult-Onset Moyamoya Disease

Background

Moyamoya disease (MMD) is a progressive occlusive cerebrovascular disease that is characterized by abnormal angiogenesis at the base of the brain. This pathological abnormal angiogenesis is susceptible to disturbances, including spontaneous hemorrhage and vasogenic edema. However, the underlying mechanisms of pathological angiogenesis and occurrence of hemorrhage are unclear. Angiopoietins play a fundamental role in the pathophysiology of central nervous system disorders in angiogenesis. This study was aimed at examining whether angiopoietins are associated with formation of abnormal collateral vessels and the occurrence of hemorrhage in adult-onset moyamoya disease (HMMD).

Methods

A total of 27 consecutive adult patients with HMMD were enrolled from June 2011 to May 2017. Serum levels of angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) were examined by enzyme-linked immunosorbent assay. Patients with HMMD were compared with those with spontaneous hemorrhage (controls) and nonhemorrhagic-onset MMD (NHMMD).

Results

Serum Ang-2 levels were significantly higher in patients with adult HMMD than in those with spontaneous hemorrhage and NHMMD. The ROC curve identified that a baseline serum Ang-2 level > 1230 ng/ml may be associated with adult HMMD with 88.39% sensitivity and 70.37% specificity (area under the curve (AUC), 0.89; 95% CI, 0.808-0.973; P < 0.001). Moreover, serum Ang-2 levels were significantly elevated in stages II, III, and IV. In subgroup analysis of a high and low degree of moyamoya vessels, serum Ang-2 levels were significantly higher in the high moyamoya vessel group than in the low moyamoya vessel group. Serum Ang-2 levels were also significantly higher in the low moyamoya vessel group compared with the control group. Serum Ang-1 levels were not significantly different among the groups.

Conclusion

Increased serum Ang-2 levels may contribute to pathological abnormal angiogenesis and/or to the instability of vascular structure and function, thus causing brain hemorrhage in adult HMMD.

[Modern trends in diagnosis and surgical treatment of moyamoya disease]

This review is devoted to moyamoya disease. It is a rare chronic steno-occlusive cerebrovascular disease. However, moyamoya disease is increasingly diagnosed by neurosurgeons in our country. Unlike atherosclerotic lesions of cerebral arteries, pathogenesis and course of this disease are much more complex and variable. Therefore, specialists often have certain difficulties in diagnosis, management and treatment of these patients. To date, a large number of surgical interventions have been proposed for the treatment of moyamoya disease. Revascularization approaches include direct procedures (extra-intracranial microanastomoses), indirect methods (synangioses) and combined revascularization. The purpose of the review is to systematize current literature data on the pathogenesis, diagnosis, clinical patterns and surgical treatment of patients with moyamoya disease. results Outcomes of surgical revascularization and the role of its various components in combined approach are under particular attention.

Dissection of the Superficial Temporal Artery: Significance and Performance with Bipolar Forceps

BACKGROUND

Adequate bypass harvesting of the superficial temporal artery (STA) is a standard procedure for every neurosurgeon, so mastery of techniques for its management and care is mandatory.

METHODS

Here, we report the effectiveness of using the bipolar forceps as a novel procedure.

RESULTS

This procedure improves safety, efficiency, and bleeding compared to the usual dissection.

CONCLUSIONS

In cases requiring an STA donor, this technique may be as useful as the traditional method and could become part of the neurosurgeon's armamentarium.

Poor outcomes in carriers of the RNF213 variant (p.Arg4810Lys) with pulmonary arterial hypertension

BACKGROUND

A variant of c.14429G>A (p.Arg4810Lys, rs112735431) in the ring finger protein 213 gene (RNF213; NM_001256071.2) has been recently identified as a risk allele for pulmonary arterial hypertension (PAH). PAH can be added as a new member of RNF213-associated vascular diseases, which include Moyamoya disease and peripheral pulmonary stenosis. Our aim was to identify the clinical features and outcomes of PAH patients with this variant.

METHODS

Whole-exome sequencing was performed in 139 idiopathic (or possibly heritable) PAH patients.

RESULTS

The RNF213 p.Arg4810Lys variant was identified in a heterozygous state in 11 patients (7.9%). Time-course changes in hemodynamics after combination therapy in the patients with the RNF213 p.Arg4810Lys variant were significantly poorer compared with those carrying the bone morphogenic protein receptor type 2 (BMPR2) mutation (n = 36) (comparison of changes in mean pulmonary arterial pressure, p = 0.007). The event-free rate of death or lung transplantation was significantly poorer in RNF213 p.Arg4810Lys variant carriers than in BMPR2 mutation carriers (5-year event-free rate since the introduction of prostaglandin I₂ infusion, 0% vs 93%, respectively; p < 0.001).

CONCLUSIONS

Idiopathic PAH patients with the RNF213 p.Arg4810Lys variant are associated with poor clinical outcomes even in recent times. Earlier consideration of lung transplantation might be required for RNF213 p.Arg4810Lys variant carriers who are developing PAH. Documentation of the RNF213 p.Arg4810Lys variant, as well as already known pathogenic genes, such as BMPR2, can provide clinically relevant information for therapeutic strategies, leading to a personalized approach for the treatment of PAH.

Surgery for Moyamoya Disease in Children

Moyamoya disease is a chronic progressive cerebrovascular occlusive disease of the terminal portion of the internal carotid arteries associated with an acquired abnormal vascular network at the base of the brain, often leading to ischemic or hemorrhagic stroke. Moyamoya disease is a relatively common cause of pediatric stroke with a specific racial and well-identified clinical and imaging phenotype. Moyamoya disease is more prevalent in East Asian countries compared with other geographic regions with a higher incidence of familial cases and clinically more aggressive form. Moyamoya disease is one of the few causes of stroke that is amenable to effective surgical revascularization treatment. There are various surgical options available for revascularization, including the direct, indirect, or combined bypass techniques, each with variable responses. However, due to the heterogeneity of the diseases, different clinical course, geographical variables associated with the disease, and availability of a wide variety of surgical revascularization procedures, optimal selection of a surgical candidate and the surgical technique becomes challenging, particularly in the pediatric population. This brief review presents pertinent literature of clinical options for the diagnosis and surgical treatment of moyamoya disease in children.

Sternocleidomastoid Encephalomyosynangiosis for Treatment-Resistant Moyamoya Disease

BACKGROUND AND IMPORTANCE

Refractory ischemic symptoms in moyamoya disease are a challenging problem, particularly in situations in which multiple direct and indirect revascularization techniques have already been employed. In addition, revascularization of the parietal lobes is difficult, as this area is a watershed between the middle cerebral artery and posterior cerebral artery distributions.

CLINICAL PRESENTATION

This is the case of a 50-yr-old woman with hemibody sensorimotor deficits, who had previously undergone bilateral arterial bypass and temporalis myosynangiosis. A method for indirect surgical cerebral revascularization is described, utilizing a rotated and tunneled sternocleidomastoid flap. The perfused muscle is approximated to the cortical surface, with adjacent sulci dissected to expose the underlying vasculature. After sternocleidomastoid encephalomyosynangiosis, the patient experienced symptomatic improvement, along with the appearance of new pial collateral vasculature on diagnostic cerebral angiography. Pre- and postoperative dynamic perfusion computed tomography with acetazolamide challenge demonstrate an increase in cerebral blood flow and decrease in mean transit time, as well as improved cerebrovascular reserve.

CONCLUSION

Sternocleidomastoid encephalomyosynangiosis using a tunneled muscle flap is a useful method for revascularization of the parietal and occipital lobes, particularly for refractory moyamoya in cases where a variety of other options have been exhausted.

Multimodal neuronavigation-guided precision bypass in adult ischaemic patients with moyamoya disease: study protocol for a randomised controlled trial

INTRODUCTION

Revascularisation surgery is an important treatment of moyamoya disease (MMD). Several general methods of revascularisation had been used: direct, indirect and combined techniques. However, there had been no reports about the criteria of recipient arteries selection in bypass surgery for MMD. Surgeons usually choose the recipient arteries by their own experiences. Their choices of the recipient arteries are various and may contribute the different outcome of patients. The purpose is to identify utility and efficacy of precision bypass guided by multimodal neuronavigation of MMD in a prospective randomised controlled trial.

METHOD AND ANALYSIS

This study is a prospective randomised controlled clinical trial. This study will enrol a total of 100 eligible patients. These eligible patients will be randomised to the empirical bypass group and the multimodal neuronavigation-guided precision bypass group in a 1:1 ratio. Patient baseline characteristics and MMD characteristics will be described. In the multimodal neuronavigation-guided group, the blood velocity and blood flow of the recipient arteries will be identified. Surgical complications and outcomes at pretreatment, post-treatment, at discharge and at 3 month, 6 month, 12 month and end of trial will be analysed with CT perfusion, MRI, digital subtraction angiography, modified Rankin Scale, National Institute of Health Stroke Scale and modified Barthel Scale. This trial will determine whether multimodal neuronavigation-guided precision bypass is superior to empirical bypass in patients with MMD and identify the safety and efficacy of multimodal neuronavigation-guided precision bypass.

ETHICS AND DISSEMINATION

The study protocol and written informed consent were reviewed and approved by the Clinical Research Ethics Committee of Peking University International Hospital. Study findings will be disseminated in the printed media. The study started in August, 2018 and expected to be completed in December, 2020.

TRIAL REGISTRATION NUMBER

NCT03516851; Pre-results.

Superficial temporal artery-to-middle cerebral artery bypass in combination with indirect revascularization in moyamoya patients ≤ 3 years of age

OBJECTIVE Revascularization is indicated in the management of moyamoya disease (MMD), with options that include direct and indirect techniques. Indirect bypass is popular in young children because the diminutive caliber of donors and recipients makes direct bypass difficult. The authors reviewed a series of patients treated with direct superficial temporal artery (STA)–to–middle cerebral artery (MCA) bypass in combination with encephalomyosynangiosis (EMS) in children 3 years or younger to demonstrate feasibility and safety. METHODS A retrospective review of all surgeries for MMD over a 19-year period identified 11 procedures in 6 patients. Surgical results, angiographic outcomes, and clinical outcomes were analyzed. RESULTS Patients had a mean age of 22.4 months. The symptomatic hemisphere was revascularized first, and the contralateral hemisphere was revascularized on average 2.8 months later in 5 patients. All direct bypasses were patent postoperatively and remained patent at late follow-up (mean 4.1 years), with both STA and MCA diameters increasing significantly (n = 5, p < 0.03). At last follow-up (mean follow-up duration, 5.0 years), favorable outcomes (modified Rankin Scale scores 0–2) were observed in 5 of the 6 patients (83%), with 1 dependent patient remaining unchanged postoperatively. CONCLUSIONS Direct STA-MCA bypass in combination with EMS for MMD is feasible and safe in patients 3 years or younger, based on favorable clinical and radiological outcomes in this patient cohort. Direct bypass should be considered when immediate revascularization is needed, without the biological delay associated with indirect bypass. ABBREVIATIONS EDAS = encephaloduroarteriosynangiosis; EMS = encephalomyosynangiosis; MCA = middle cerebral artery; MMD = moyamoya disease; mRS = modified Rankin Scale; STA = superficial temporal artery; TIA = transient ischemic attack.

Flattening the curvature of synthetic materials to relieve scalp skin tension in cranioplasty

BACKGROUND

Scalp tissue shrinkage and volume contraction is a major problem in cranioplasty, and sometimes a tissue expander must be set before cranioplasty. The procedure for placing scalp expanders is cumbersome. In this study, we present a method for flattening the curvature of synthetic materials to relieve scalp skin tension and discuss the feasibility and limitations of the method.

METHODS

A total of 25 cranioplasty patients were included in this study. The optimal degree of curvature flattening for each piece of bone substitute material was determined based on cosmetic considerations and the extent of encephalomalacia or atrophy due to primary disease. In this series, the correlation between the degree of curvature flattening and the size or location of the bone flap was considered, and the amount of scalp surface area that could be obtained through curvature flattening was estimated.

RESULTS

The median degree of curvature flattening was 5.0 mm. The degree of curvature flattening showed moderate correlation with the rate of change in the area of synthetic material achieved through curvature flattening (p < 0.001). The 21 cases of fronto-temporal craniectomy were divided into two groups according to the distance from the midline. There was a statistically significant difference between these two groups in degree of flattening curvature.

CONCLUSIONS

In the present cranioplasty series using synthetic materials, curvature flattening was a non-invasive and convenient method for skin closure. This method can be beneficial especially in patients requiring a larger craniotomy including convexity regions.

Pedicled temporoparietal fascial flap for combined revascularization in adult moyamoya disease

Moyamoya disease (MMD) is a progressive, idiopathic cerebrovascular occlusive disease. Various revascularization techniques including direct, indirect, and combined microvascular bypasses have been described. This article presents a modified revascularization technique for MMD utilizing a pedicled temporoparietal fascial flap (TPFF) for combined revascularization. This technique combines a large area of coverage for indirect revascularization with the benefits of a direct bypass. The pedicled TPFF also benefits from intact venous drainage to minimize the risk of flap swelling that could result in complications from mass effect.

Rupture of a Middle Meningeal Artery Pseudoaneurysm in Moyamoya Syndrome Related with Tuberculous Meningitis

We report a rare case of a patient with Moyamoya syndrome who presented with intracerebral hemorrhage resulting from rupture of a middle meningeal artery pseudoaneurysm. This 38-year-old woman was unconscious and hemiplegic when she was admitted to our hospital. The patient had mental retardation as a result of tuberculous meningitis infection at the age of one year. On radiologic examination, she had intracerebral hemorrhage in the right temporo-parietal lobe and an aneurysm in the middle meningeal artery with right internal carotid artery occlusion. The patient underwent surgical treatment for the hemorrhage and aneurysm. The radiologic data, intraoperative findings, and pathology were consistent with a diagnosis of pseudoaneurysm. In the current report, we describe a rare case of a patient with a history of tuberculous meningitis who developed Moyamoya syndrome and pseudoaneurysm, which resulted in a ruptured middle meningeal artery pseudoaneurysm and brain hemorrhage.

[Revascularization experience and results in ischaemic cerebrovascular disease: Moyamoya disease and carotid occlusion]

INTRODUCTION

Cerebral revascularization techniques are an indispensable tool in the current armamentarium of vascular neurosurgeons. We present revascularization surgery experience and results in both moyamoya disease and occlusive cerebral ischaemia.

PATIENTS AND METHODS

Patients with ischaemic occlusive disease and moyamoya disease who underwent microsurgical revascularization between October 2014 and September 2017 were analysed.

RESULTS

In the study period, 23 patients with occlusive ischaemic disease underwent microsurgical revascularization. Three patients presented with serious postoperative complications (2 intraparenchymal haemorrhages in the immediate postoperative period and one thrombosis of the femoral artery). All patients, except one, achieved normalization of the cerebral hemodynamic reserve (CHR) in the SPECT study. Twenty patients had a good neurological result, with no ischaemic recurrence of the revascularized territory. Among patients with moyamoya, 20 had moyamoya disease and 5 had moyamoya syndrome with unilateral involvement. Five patients were treated at paediatric age. Haemorrhagic onset occurred in 2 patients. The CHR study showed hemodynamic compromise in all patients. Cerebral SPECT at one year showed resolution of the hemodynamic failure in all patients. There have been 4 postoperative complications (acute subdural hematoma, two subdural collections and one dehiscence of the surgical wound). No patient presented with neurological worsening at 6 and 12months of follow-up.

CONCLUSIONS

Cerebral revascularization through end-to-side anastomosis between the superficial temporal artery and a cortical branch of the middle cerebral artery is an indisputable technique in the treatment of moyamoya disease and possibly in a subgroup of patients with symptomatic occlusive ischaemic cerebrovascular disease.

Clinical and angiographic outcomes after combined direct and indirect bypass in adult patients with moyamoya disease: A retrospective study of 76 procedures

The present retrospective study was performed to evaluate the clinical outcome, as well as post-operative collateral formation and revascularization patterns in combined bypass. Surgical revascularization has been the mainstay of treatment for moyamoya patients. A total of 76 hemispheres from 64 moyamoya patients undergoing combined superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis and encephalo-duro-myo-synangiosis (EDMS) were retrospectively reviewed. Computed tomography perfusion and DSA were routinely performed. Modified Rankin scale (mRS) scoring and Kaplan-Meier analysis were performed, and post-operative collateral grading on digital subtraction angiography (DSA), reconstruction patterns and vessel diameter were measured to evaluate the revascularization area and vascular compensatory effect. During the follow-up period, the chief complaint was partially alleviated in 57/64 patients (89.1%). In all patients, mRS was significantly decreased after the operation. Good revascularization was established in most patients at 6 months after the surgery: 92.1% of sides were scored as 2 and 77.6% were scored as 3 by post-operative collateral grading on DSA. Dominant collateral revascularization originating from EDMS was more frequent than that from STA-MCA anastomosis (31 vs. 19 hemispheres) at 6-month follow-up. Morphologically, the calibers of the STA main trunk (2.60±0.65 mm) increased profoundly at the first 10 post-operative days (3.32±1.05 mm) and shrank back to pre-operative status at 6 months (2.20±1.01 mm) and 12 months (2.36±0.73 mm) according to DSA examination. Middle meningeal artery (MMA) and deep temporal artery (DTA) demonstrated continuous augmentation during the follow-up time (from 1.30±0.46 to 1.87±0.69 mm for MMA and 1.11±0.25 to 2.11±1.16 mm for DTA). These results strongly suggested that combined STA-MCA bypass and EDMS provided efficient revascularization and reduced acute cerebral events. The direct STA-MCA bypass provided early augmentation of cerebral perfusion, whereas the indirect EDMS provided a more durable long-term revascularization, indicating a complementary association between the two revascularization methods.

Magnetic Resonance Imaging (MRI) and Digital Subtraction Angiography Investigation of Childhood Moyamoya Disease

Because digital subtraction angiography (DSA) is not an ideal angiographic examination for moyamoya disease in the pediatric population, magnetic resonance angiography (MRA) provides a noninvasive contrast-free angiographic examination; whereas magnetic resonance imaging (MRI) provides superior spatial resolution and soft-tissue contrast for lesion assessment. Ninety patients with moyamoya disease were examined by MRI and DSA to assess the distribution of lesions and their diagnostic agreement between modalities. MRI examination revealed 439 lesions. Punctate lesions were the most abundant, followed by patchy lesions. These lesions generally covered a smaller area than the abnormal-vascular corresponding brain parenchyma. Steno-occlusive changes at bilateral anterior, medial, and posterior cerebral arteries were identified by MRA and DSA. MRI showed moderate agreement in identifying lesions after steno-occlusive changes in anterior and medial cerebral arteries, and good agreement in posterior cerebral arteries; 6% to 11% of cases were misdiagnosed by MRA.

Direct versus indirect revascularization in the treatment of moyamoya disease

OBJECTIVE For patients with moyamoya disease (MMD), surgical intervention is usually required because of progressive occlusion of the internal carotid artery. The indirect bypass method has been widely accepted as the treatment of choice in pediatric patients. However, in adult patients with MMD, the most effective treatment method remains a matter of debate. Here, the authors compared the clinical outcomes from MMD patients treated with either extracranial-intracranial arterial bypass (EIAB; 43 hemispheres) or modified encephaloduroarteriosynangiosis (mEDAS; 75 hemispheres) to investigate whether mEDAS is an effective surgical method for treating adults with symptomatic MMD. METHODS A comparative analysis was performed in patients treated using either mEDAS or EIAB. Collateral grading, collateral vein counting, and symptom analysis were used to assess the outcome of surgery. RESULTS Seventy-seven percent (58/75) of mEDAS cases and 83.7% (36/43) of EIAB cases in the analysis experienced improvement in their symptoms after surgery. Furthermore, patients in 98.7% (74/75) of mEDAS cases and those in 95.3% (41/43) of EIAB cases exhibited improved collateral grades. Increases in regions of perfusion were seen after both procedures. CONCLUSIONS Modified EDAS and EIAB both result in positive outcomes for symptomatic adults with MMD. However, when considering the benefit of both surgeries, the authors propose mEDAS, a simpler and less strenuous surgery with a lower risk of complications, as a sufficient and safe treatment option for symptomatic adults with MMD.

Patient Selection and Clinical Efficacy of Urgent Superficial Temporal Artery-Middle Cerebral Artery Bypass in Acute Ischemic Stroke Using Advanced Magnetic Resonance Imaging Techniques

BACKGROUND: Selected patients with acute ischemic stroke might benefit from superficial temporal artery-middle cerebral artery (STA-MCA) bypass, but the indications for urgent STA-MCA bypass are unknown.

OBJECTIVE: To report our experiences of urgent STA-MCA bypass in patients requiring urgent reperfusion who were ineligible for other reperfusion therapies, using advanced magnetic resonance imaging (MRI) techniques.

METHODS: The inclusion criteria for urgent STA-MCA bypass were as follows: acute infarct volume &lt;70 mL with a ratio of perfusion/diffusion lesion volume ≥1.2, and a regional cerebral blood volume ratio &gt;0.85. From January 2013 to October 2015, 21 urgent STA-MCA bypass surgeries were performed. The control group included 19 patients who did not undergo bypass surgery mainly due to refusal of surgery or the decision of the neurologist. Clinical and radiological data were compared between the surgery and control group.

RESULTS: The median age of the control group (70 years, interquartile range [IQR] 58-76) was higher than that of the surgery group (62 years, IQR 49-66), but the median preoperative diffusion and perfusion lesion volumes of the surgery group (13.8 mL, IQR 7.5-26.0 and 120.9 mL, IQR 84.9-176.0, respectively) were higher than those of the control group (5.6 mL, IQR 2.1-9.1 and 69.7 mL, IQR 23.9-125.3, respectively). Sixteen (76.2%) patients in the surgery group and 2 (10.5%) patients in the control group had favorable outcomes (P &lt; .001). Logistic regression analysis identified bypass surgery as the strongest predictive factor.

CONCLUSION: STA-MCA bypass can be used as a therapeutic tool for acute ischemic stroke. Advanced MRI techniques are helpful for selecting patients and for decision making.

Moore J, Adeeb N, Griessenauer CJ, Patel AS, Chua MH, Thomas AJ, Ogilvy CS. Clinical presentation, progression, and treatment outcomes of moyamoya disease in the elderly

BACKGROUND

Moyamoya disease is a vascular disorder characterized by progressive stenosis of the internal carotid artery. The presentation, progression, treatment options, and post-operative clinical outcomes for elderly (60 and older) Moyamoya patients have never been reported.

METHODS

A retrospective analysis of all patients who were diagnosed with Moyamoya disease by the senior authors between 1991 and 2016 was performed. Patients who were 60 years or older at the time of surgery or last follow-up were further evaluated.

RESULTS

Seventy patients were diagnosed with probable or definite Moyamoya disease during the study period (1991-2016). Eight patients (11.4 %; six females: two males; median age 63; range, 60-71 years) were found to be 60 years or older at the time of surgery or last follow-up and were included in the study. All patients had a modified Rankin scale (mRS) of either one or two (median 1) pre-operatively. Six patients (75 %) underwent surgical treatment on a total on seven hemispheres. Post-surgery, one patient had an improved mRS score, three had no changes, and two had worsening in their mRS scores. Both patients who did not undergo surgical interventions suffered from intra-parenchymal hemorrhages post-diagnosis.

CONCLUSIONS

Moyamoya disease is most commonly seen in young and middle-aged patients. Presentation in the elderly (defined as 60 years and older in this study) is rare, and has never been reported in the literature. In this study, both direct and indirect revascularization procedures demonstrated potential benefit in some of these patients, with stabilization of progressive symptoms.

Emergent Double-barrel Bypass Shortly after Intravenous Administration of Recombinant Tissue Plasminogen Activator for Acute Ischemic Stroke

Although intravenous recombinant tissue plasminogen activator (IV rt-PA) is effective in many cases of acute ischemic stroke, the neurologic symptoms can worsen after IV rt-PA because of sustained vessel occlusion. For such cases, several reperfusion modalities are available, including intra-arterial thrombolysis (IAT), carotid endarterectomy, and superficial temporal artery-middle cerebral artery (STA-MCA) bypass. Invasive procedures, such as major surgery, should be generally avoided within 24 hours after the administration of IV rt-PA. A 66-year-old man with no previous medical history developed left hemiparesis. A computed tomography scan revealed no acute lesion and he received IV rt-PA within 1.5 hours after symptom onset. Emergent magnetic resonance imaging showed significant diffusion-perfusion mismatch. He received IAT 2 hours after IV rt-PA administration, but IAT failed because of total occlusion of the cervical internal carotid artery. We initially planned to perform STA-MCA bypass the next morning because he had received IV rt-PA, but, 8 hours after IV rt-PA administration, his hemiparesis worsened from motor grade 3/4 to motor grade 1/2. Because of the large perfusion defect in both MCA divisions, double-barrel STA-MCA bypass was performed 10 hours after IV rt-PA administration. His symptoms rapidly improved after surgery and his modified Rankin Scale score 3 months later was grade 0. We suggest that emergent double-barrel bypass can be a viable option in patients who have perfusion defects of both MCA divisions in acute ischemic stroke after IV rt-PA administration.

Direct versus indirect revascularization procedures for moyamoya disease: a comparative effectiveness study

OBJECTIVE Moyamoya disease (MMD) is a chronic cerebrovascular disease that can lead to devastating neurological outcomes. Surgical intervention is the definitive treatment, with direct, indirect, and combined revascularization procedures currently employed by surgeons. The optimal surgical approach, however, remains unclear. In this decision analysis, the authors compared the effectiveness of revascularization procedures in both adult and pediatric patients with MMD. METHODS A comprehensive literature search was performed for studies of MMD. Using complication and success rates from the literature, the authors constructed a decision analysis model for treatment using a direct and indirect revascularization technique. Utility values for the various outcomes and complications were extracted from the literature examining preferences in similar clinical conditions. Sensitivity analysis was performed. RESULTS A structured literature search yielded 33 studies involving 4197 cases. Cases were divided into adult and pediatric populations. These were further subdivided into 3 different treatment groups: indirect, direct, and combined revascularization procedures. In the pediatric population at 5- and 10-year follow-up, there was no significant difference between indirect and combination procedures, but both were superior to direct revascularization. In adults at 4-year follow-up, indirect was superior to direct revascularization. CONCLUSIONS In the absence of factors that dictate a specific approach, the present decision analysis suggests that direct revascularization procedures are inferior in terms of quality-adjusted life years in both adults at 4 years and children at 5 and 10 years postoperatively, respectively. These findings were statistically significant (p < 0.001 in all cases), suggesting that indirect and combination procedures may offer optimal results at long-term follow-up.

Moyamoya angiopathy - Is there a Western phenotype?

Moyamoya disease (MMD) is a chronic cerebrovascular disease involving progressive bilateral stenosis of the intracranial segments of the internal carotid arteries. It results in the development of a rich, but friable collateral supply, prone to rupture. The disease is well described in Japanese literature and was originally thought to be a predozminantly Eastern disease. However, the recent literature describes a Western phenotype that may present with a different clinical course. This review aims to describe the variations in the epidemiology of the MMD between Eastern and Western populations, the possible reasons for them and highlight their implications for clinical practise and future research.

Rapid resolution of brain ischemic hypoxia after cerebral revascularization in moyamoya disease

BACKGROUND

In moyamoya disease (MMD), cerebral revascularization is recommended in patients with recurrent or progressive ischemic events and associated reduced cerebral perfusion reserve. Low-flow bypass with or without indirect revascularization is generally the standard surgical treatment. Intraoperative monitoring of cerebral partial pressure of oxygen (PtiO2) with polarographic Clark-type probes in cerebral artery bypass surgery for MMD-induced chronic cerebral ischemia has not yet been described.

OBJECTIVE

To describe basal brain tissue oxygenation in MMD patients before revascularization as well as the immediate changes produced by the surgical procedure using intraoperative PtiO2 monitoring.

METHODS

Between October 2011 and January 2013, all patients with a diagnosis of MMD were intraoperatively monitored. Cerebral oxygenation status was analyzed based on the Ptio2/PaO2 ratio. Reference thresholds of PtiO2/PaO2 had been previously defined as below 0.1 for the lower reference threshold (hypoxia) and above 0.35 for the upper reference threshold (hyperoxia).

RESULTS

Before STA-MCA bypass, all patients presented a situation of severe tissue hypoxia confirmed by a PtiO2/PaO2 ratio <0.1. After bypass, all patients showed a rapid and sustained increase in PtiO2, which reached normal values (PtiO2/PaO2 ratio between 0.1 and 0.35). One patient showed an initial PtiO2 improvement followed by a decrease due to bypass occlusion. After repeat anastomosis, the patient's PtiO2 increased again and stabilized.

CONCLUSION

Direct anastomosis quickly improves cerebral oxygenation, immediately reducing the risk of ischemic stroke in both pediatric and adult patients. Intraoperative PtiO2 monitoring is a very reliable tool to verify the effectiveness of this revascularization procedure.

Inherited neurovascular diseases affecting cerebral blood vessels and smooth muscle

Neurovascular diseases are among the leading causes of mortality and permanent disability due to stroke, aneurysm, and other cardiovascular complications. Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) and Marfan syndrome are two neurovascular disorders that affect smooth muscle cells through accumulation of granule and osmiophilic materials and defective elastic fiber formations respectively. Moyamoya disease, hereditary hemorrhagic telangiectasia (HHT), microcephalic osteodysplastic primordial dwarfism type II (MOPD II), and Fabry's disease are disorders that affect the endothelium cells of blood vessels through occlusion or abnormal development. While much research has been done on mapping out mutations in these diseases, the exact mechanisms are still largely unknown. This paper briefly introduces the pathogenesis, genetics, clinical symptoms, and current methods of treatment of the diseases in the hope that it can help us better understand the mechanism of these diseases and work on ways to develop better diagnosis and treatment.

'Smoke in the air': a rare cerebrovascular cause of neurological signs and symptoms in a young adult

Moyamoya disease is a rare neurological condition that affects children and adults of all ages. It is characterized by chronic, progressive stenosis of the circle of Willis that ultimately leads to the development of extensive collateral vessels. Presenting symptoms are usually due to cerebral ischemia or hemorrhage. The Japanese term moyamoya (meaning puffy or obscure) was coined to describe the characteristic 'smoke in the air' appearance of these vessels on cerebral angiography. Moyamoya has the highest recorded incidence in Japan (0.28 per 100,000). In the west it is an extremely rare condition with an overall incidence of (0.086 per 100,000) in the Western United States. Etiology for the most part is unknown; however, genetic susceptibility related to RNF213 gene on chromosome 17q25.3 has been suggested. Moyamoya is being diagnosed more frequently in all races with varying clinical manifestations. Moyamoya disease is a rare progressive neurologic condition characterized by occlusion of the cerebral circulation with extensive collaterals recruitment in children and adults. Distinguished radiological findings confirm the diagnosis. Early recognition and swift institution of therapy is vital in order to minimize neurological deficits. We present the case of a 19-year-old African American female who presented with left-sided parastheia, weakness, and headache for 2 days duration.

Surgical Revascularization in North American Adults with Moyamoya Phenomenon: Long-Term Angiographic Follow-up

BACKGROUND

North American and Asian forms of moyamoya have distinct clinical characteristics. Asian adults with moyamoya are known to respond better to direct versus indirect revascularization. It is unclear whether North American adults with moyamoya have a similar long-term angiographic response to direct versus indirect bypass.

METHODS

A retrospective review of surgical revascularization for adult moyamoya phenomenon was performed. Preoperative and postoperative cerebral angiograms underwent consensus review, with degree of revascularization quantified as extent of new middle cerebral artery (MCA) territory filling.

RESULTS

Late angiographic follow-up was available in 15 symptomatic patients who underwent 20 surgical revascularization procedures. In 10 hemispheres treated solely with indirect arterial bypass, 3 had 2/3 revascularization, 4 had 1/3 revascularization, and 3 had no revascularization of the MCA territory. In the 10 hemispheres treated with direct arterial bypass (8 as a stand-alone procedure and 2 in combination with an indirect procedure), 2 had complete revascularization, 7 had 2/3 revascularization, and 1 had 1/3 revascularization. Direct bypass provided a higher rate of "good" angiographic outcome (complete or 2/3 revascularization) when compared with indirect techniques (P = .0198).

CONCLUSIONS

Direct bypass provides a statistically significant, more consistent, and complete cerebral revascularization than indirect techniques in this patient population. This is similar to that reported in the Asian literature, which suggests that the manner of presentation (ischemia in North American adults versus hemorrhage in Asian adults) is likely not a contributor to the extent of revascularization achieved after surgical intervention.

Is local hypoperfusion the reason for transient neurological deficits after STA-MCA bypass for moyamoya disease?

OBJECT

Hyperperfusion is believed to be the cause of transient neurological events (TNEs) in patients with moyamoya disease (MMD) who have undergone an extracranial-to-intracranial (EC-IC) bypass between the superficial temporal artery (STA) and the middle cerebral artery (MCA). The objective of this study was to evaluate this possibility by analyzing cerebral blood flow (CBF) data obtained with thermal diffusion probes used at the authors' center.

METHODS

The authors examined postoperative cerebral perfusion in 31 patients with MMD who underwent a direct EC-IC STA-MCA bypass. A Hemedex Q500 flow probe was placed in the frontal lobe adjacent to the bypass and connected to a Bowman cerebral perfusion monitor, and CBF data were statistically analyzed using JMP 8.0.2 software. Seven patients experienced a TNE after surgery in the left hemisphere (that is, after left-sided surgery), manifesting as dysphasia approximately 24 hours postoperatively and which had improved by 48 hours. No TNEs were observed after right-sided surgeries. Operative and postoperative CBFs in the left side with the TNE were compared with those in the left side with no TNE and on the right side.

RESULTS

A detailed analysis of 64,980 minute-by-minute flow observations showed that the initial postbypass CBF was higher on the left side where the TNEs occurred. This CBF increase was followed by a widely fluctuating pattern and a statistically significant and sharp drop in perfusion (p < 0.001, mean difference of CBF between groups, paired t-test) associated with a TNE not observed in the other 2 groups.

CONCLUSIONS

On the basis of the authors' initial observations, an early-onset altered pattern of CBF was identified. These findings suggest local hypoperfusion as the cause of the TNEs. This hypoperfusion may originate from competing blood flows resulting from impaired cerebral autoregulation and a fluctuating flow in cerebral microcirculation.

Cephalometric Features of Moyamoya Disease: A case control study

CONTRIBUTION OF AUTHORS

Adnan I Qureshi, Waqas I Gilani MD, Sarwat I. Gilani MD, Malik M. Adil MD . Equally assisted in the synthesis and discussion of ideas, and share equal responsibility for the information written in the manuscript above.

CONFLICT OF INTEREST

No conflict of interests.

RUNNING TITLE

Cephalometric Features of Moyamoya Disease.

BACKGROUND

Moyamoya disease is highly prevalent among patients with syndromes that have unique cephalometric characteristics such as Down syndrome. We performed a case control study to investigate the relationship between cephalometric parameters and Moyamoya disease.

METHODS

Patients [aged 16-82 years] with angiographically confirmed Moyamoya disease who underwent cranial CT scan were analyzed. We identified three controls for each patient who were matched for age (±1 year), gender, and race (white or African American). The fronto-occipital diameter, bi-parietal diameter, and distance between bregma and occiput were measured from the head CT scans of cases and controls. The cephalic index was calculated by determining the ratio between bi-parietal diameter and fronto-occipital diameter and multiplying the value by 100.

RESULTS

A total of 13 cases of Moyamoya disease and 39 controls were analyzed. The stage of Moyamoya disease in cases was as follows: stage 1 (n=0), stage 2 (n=1), stage 3 (n=4), stage 4 (n=2), stage 5 (n=5) and stage 6 (n=1). There was a significantly greater bi-parietal diameter in Moyamoya disease patients compared with controls (141.5±3.7 mm versus 136.9±5.4 mm, p=0.007). There was a significantly greater fronto-occipital diameter in Moyamoya disease patients compared with controls (186.5±6.5 mm versus 180.2±8.7mm, p=0.02). The distance between bregma and occiput was shorter among cases compared with controls (81.1±6.2 versus 87.5±7.0, p=0.01).

CONCLUSIONS

We observed an association between cephalometric parameters and Moyamoya disease. Further study of the unique cephalometric characteristics among Moyamoya disease patients may provide additional insight into disease occurrence in white and African American populations.

Advances and surgical considerations in the treatment of moyamoya disease

Moyamoya is a rare disorder that involves steno-occlusive arterial changes of the anterior circulation, along with proliferative development of basal arterial collaterals. It is either idiopathic (called moyamoya disease) or the result of a specific underlying condition such as atherosclerosis, radiation therapy, or sickle cell disease (called moyamoya syndrome or phenomenon). In recent years, numerous insights into and advances in the understanding, evaluation, and management of moyamoya patients have occurred. This article briefly reviews the spectrum of moyamoya conditions and then provides a synopsis of numerous recent investigations that shed light on various aspects of the disease, including its clinical characteristics, natural history, underlying pathology, imaging, surgical techniques, and long-term patient outcome.

Clinical and angiographic findings in Moya Moya

Patient: Female, 40

Final Diagnosis: Moya-Moya Disease

Symptoms: Blurred vision • headache • lethargy

Medication: —

Clinical Procedure: —

Specialty: Neurology