Moyamoya syndrome associated with congenital heart disease

Computational Modelling of Cerebral Blood Flow Rate at Different Stages of Moyamoya Disease in Adults and Children

Moyamoya disease is a cerebrovascular disorder which causes a decrease in the cerebral blood flow rate. In this study, a lumped parameter model describing the pressures and flow rates in the heart chambers, circulatory system, and cerebral circulation with the main arteries in the circle of Willis, pial circulation, cerebral capillaries, and veins was used to simulate Moyamoya disease with and without coarctation of the aorta in adults and children. Cerebral blood flow rates were 724 mL/min and 1072 mL/min in the healthy adult and child cardiovascular system models. The cerebral blood flow rates in the adult and child cardiovascular system models simulating Moyamoya disease were 676 mL/min and 1007 mL/min in stage 1, 627 mL/min and 892 mL/min in stage 2, 571 mL/min and 831 in stage 3, and 444 and 537 mL/min in stage 4. The cerebral blood flow rates were 926 mL/min and 1421 mL/min in the adult and child cardiovascular system models simulating coarctation of the aorta. Furthermore, the cerebral blood flow rates in the adult and child cardiovascular system model simulating Moyamoya disease with coarctation of the aorta were 867 mL/min and 1341 mL/min in stage 1, 806 mL/min and 1197 mL/min in stage 2, 735 mL/min and 1121 in stage 3, and 576 and 741 mL/min in stage 4. The numerical model utilised in this study can simulate the advancing stages of Moyamoya disease and evaluate the associated risks with Moyamoya disease.

Moyamoya Disease Complicating Ebstein's Anomaly

Ebstein's anomaly is an uncommon congenital disorder affecting the tricuspid valve. We herein report a 38-year-old woman who experienced consciousness and sensory disturbance during treatment for heart failure caused by Ebstein's anomaly. Urgent magnetic resonance imaging and cerebral angiography demonstrated acute cerebral infarction and internal carotid artery obstruction with the development of collateral arteries. We diagnosed her with multiple cerebral infarctions due to moyamoya disease. Ebstein's anomaly concomitant with moyamoya disease is extremely rare. However, we should consider the possibility of this rare but important concurrence when treating patients with heart failure due to Ebstein's anomaly to avoid excessive diuresis and vasodilation and irreversible brain injury.

Cephalic/cardiac neural crest cell and moyamoya disease

BACKGROUND

The neural crest is a transient structure present in early embryogenesis. Cephalic neural crest cells migrate into the pharyngeal arches and the frontonasal process that becomes the forehead and midfacial structures. They also contribute to forming the media of the arteries of the circle of Willis and their branches. The cardiac neural crest produces vascular smooth muscle cells in the ascending aorta, cardiac septum and coronary arteries.

METHODS

In this review, we evaluate the role of the neural crest in moyamoya disease and the pathological implications from the concurrence of moyamoya disease and cardiovascular diseases from the point of view of neural crest cell distributions.

RESULTS

Midline craniofacial and central nervous system anomalies with eye anomalies, morning glory disc anomaly in patients with moyamoya disease can both be explained as a subtype of cephalic neurocristopathy. Further, the association between moyamoya disease and cardiac manifestations (congenital cardiac defects and coronary artery disease) have also been reported. Both the cephalic neural crest and cardiac neural crest contribute to these concurrent arterial diseases, as cardio-cephalic neurocristopathy.

CONCLUSION

The concept of cephalic/cardio-cephalic neurocristopathy provides a new perspective to understanding the underlying aetiological associations and to developing future therapeutic approaches for concomitant moyamoya disease and cardiovascular diseases.

Moyamoya Disease in a Six Month Caucasian Female

Moyamoya disease (MMD) is a progressive cerebral arteriopathy characterized by stenosis and/or occlusion of the internal carotid arteries and the arteries around the Circle of Willis, with the development of "moyamoya" vessels, which are an attempt at revascularization at the base of the brain. In this paper we describe a 6 month, 3-week-old girl who presented with seizures and strokes due to moyamoya disease. The diagnosis of early onset MMD was made due to the magnetic resonance angiography results showing severe stenosis of the terminal/supraclinoid carotid arteries bilaterally with moyamoya vessels, and a completely novel de novo mutation in the RNF213 gene. She underwent bilateral encephaloduroarteriosynangiosis (EDAS) five months after her initial presentation and she did pretty well subsequently. She has shown no episodes suggestive of further strokes up to one year after surgery.

Moyamoya disease factor RNF213 is a giant E3 ligase with a dynein-like core and a distinct ubiquitin-transfer mechanism

RNF213 is the major susceptibility factor for Moyamoya disease, a progressive cerebrovascular disorder that often leads to brain stroke in adults and children. Characterization of disease-associated mutations has been complicated by the enormous size of RNF213. Here, we present the cryo-EM structure of mouse RNF213. The structure reveals the intricate fold of the 584 kDa protein, comprising an N-terminal stalk, a dynein-like core with six ATPase units, and a multidomain E3 module. Collaboration with UbcH7, a cysteine-reactive E2, points to an unexplored ubiquitin-transfer mechanism that proceeds in a RING-independent manner. Moreover, we show that pathologic MMD mutations cluster in the composite E3 domain, likely interfering with substrate ubiquitination. In conclusion, the structure of RNF213 uncovers a distinct type of an E3 enzyme, highlighting the growing mechanistic diversity in ubiquitination cascades. Our results also provide the molecular framework for investigating the emerging role of RNF213 in lipid metabolism, hypoxia, and angiogenesis.

Cardiac manifestations in a western moyamoya disease population: a single-center descriptive study and review

An embryological association between moyamoya disease (MMD) and cardiac manifestations has been proposed. Data up to this point remains anecdotal, and the prevalence of cardiac manifestations in a western MMD population is uncertain. The objective of this study was to determine the prevalence of cardiac manifestations including coronary artery disease (CAD) and congenital cardiac defects in a mostly Caucasian population of MMD patients and review prior reports of such cases. Medical records of MMD patients who presented to our institution between 1990 and 2019 were retrospectively reviewed for the presence of various congenital cardiac malformations and concomitant CAD. The prevalence of congenital cardiac defects and CAD was determined. A literature search for prior cases of MMD with concomitant cardiac manifestations was performed. A total of 181 MMD patients were included in our analysis, 139 (76.8%) of whom were Caucasian. Ten patients had cardiac manifestations (5.5%). There were six total MMD patients with congenital cardiac defects (3.3%). All patients with congenital defects were diagnosed in childhood. The prevalence of congenital defects in MMD was slightly higher than the general population as reported previously (0.8-1.2%). Four MMD patients had CAD (2.2%). The mean age of patients with CAD was 41.0 years (SD = 12.3, range = 33-59) in our series and 33.1 years (SD = 15.0) in a review of prior reports. These mean ages of CAD are in contrast to the 7th and 8th decades of lifein the general population as indicated by prior studies. Our findings support an association between MMD and cardiac manifestations. Further investigation is warranted in order to further characterize this potential relationship and shed light on a possible cardio-cephalic neural crest syndrome.

Clinical Characteristics of Moyamoya Angiopathy in a Pediatric Cohort

Moyamoya angiopathy is a rare cerebral vasculopathy characterized by a progressive stenosis of the terminal portion of the internal carotid arteries and the development of abnormal collateral vessels. Children with moyamoya angiopathy become symptomatic because of cerebral ischemic complications, and many patients eventually need revascularization. In most pediatric patients with this disease, the etiology is likely genetic. We aim to report clinical characteristics of a single-center cohort of pediatric patients with moyamoya. We performed a retrospective chart review of patients <18 years with angiographically confirmed moyamoya disease evaluated at our institution. An in-house text search tool, Advanced Cohort Explorer, was used to filter electronic medical records for patients with a diagnosis of moyamoya angiopathy from January 1999 to December 2018. The inclusion criteria were age <18 years at the time of onset of disease and a diagnosis confirmed at Mayo clinic. Fifty-one patients met the inclusion criteria. Fifty-five percent of our cohort were male, and the median age was 9 years. Three patients had a family history of moyamoya disease. Approximately half of our patients had bilateral disease. Sixteen patients had a genetic or chromosomal diagnosis (Down syndrome and NF1 being most common). Congenital anomalies like heart defects and renal dysplasia were also noted. This study is unique in that it was a large study on pediatric patients with moyamoya angiopathy. It also highlights the importance of considering genetic syndromes as an underlying cause when moyamoya angiopathy starts early in life.

Childhood Moyamoya: Looking Back to the Future

Moyamoya is a chronic, progressive steno-occlusive arteriopathy that typically affects the anterior circulation arteries of the circle of Willis. A network of deep thalamoperforating and lenticulostriate collaterals develop to by-pass the occlusion giving rise to the characteristic angiographic "puff of smoke" appearance. Moyamoya confers a lifelong risk of stroke and neurological demise, with peak age of presentation in childhood ranging between five and 10 years. Moyamoya disease refers to patients who do not have a comorbid condition, whereas moyamoya syndrome refers to patients in whom moyamoya occurs in association with an acquired or inherited disorder such as sickle cell disease, neurofibromatosis type-1 or trisomy 21. The incidence of moyamoya disease and moyamoya syndrome demonstrates geographic and ethnic variation, with a predominance of moyamoya disease in East-Asian populations. Antiplatelet therapy and surgical revascularization procedures are the mainstay of management, as there are no available treatments to slow the progression of the arteriopathy. Future research is required to address the major gaps that remain in our understanding of the pathologic basis, optimal timing for surgery, and determinants of outcome in this high-stroke risk condition of childhood.

Cardio-cephalic neural crest syndrome: A novel hypothesis of vascular neurocristopathy

A novel hypothesis proposes that "cardio-cephalic neural crest (NC) syndrome," i.e. cephalic NC including cardiac NC, contributes to the concurrent occurrence of vascular diseases in the cardio- and cerebrovascular regions. NC is a transient structure present in early embryogenesis. Cephalic NC provides mesenchymal cells to the vascular media in these regions. Concurrent cardio- and cerebrovascular lesions have been reported in PHACE syndrome, ACTA2 mutation syndrome, and less frequently in the spontaneous occlusion of the circle of Willis (so-called moyamoya disease). Cardiovascular lesions in these syndromes include coarctation of the aorta, persistent truncus arteriosus, patent ductus arteriosus, and coronary artery disease, and cerebrovascular lesions include agenesis and stenosis/occlusion of the internal carotid arteries, and moyamoya phenomenon. These concurrent vascular lesions both in the cardio- and cerebrovascular regions might be related to cephalic NC. This hypothesis, although not proven, may facilitate a better understanding of the above-mentioned NC-related vascular pathologies and lead to appropriate diagnostic and therapeutic approaches for clinicians and chart future direction for researchers.

Unusual association between lysinuric protein intolerance and moyamoya vasculopathy

INTRODUCTION

Lysinuric protein intolerance (LPI) is a form of inherited aminoaciduria caused by a deficiency in the cationic amino acid transport process on the basolateral membrane of enterocytes and renal tubular cells. Clinical signs include gastrointestinal symptoms, failure to thrive, hepatosplenomegaly, osteoporosis, episodes of coma, intellectual deficiency, lung and renal involvement, bone marrow abnormalities, as well as altered immune response. Moyamoya disease is a cerebrovascular disorder predisposing sufferers to stroke through progressive stenosis of the intracranial internal carotid arteries and their proximal branches. Patients with characteristic moyamoya vasculopathy who also exhibit well-recognized associated conditions, such as Down syndrome or sickle-cell disease, are diagnosed with moyamoya syndrome, whereas those with no known associated risk factors are said to suffer from moyamoya disease.

CASE STUDY

A 5-year-old girl exhibiting aversion to protein-rich food and splenomegaly presented with a history of recurrent ischemic strokes. Cerebral angiography confirmed moyamoya vasculopathy. Metabolic investigation revealed abnormalities characteristic of LPI. This diagnosis was confirmed by the detection of a mutation within the SLC7A7 gene upon molecular investigation.

CONCLUSION

To the best of our knowledge, this is the first reported case of an association between moyamoya vasculopathy and LPI. While the question of association or coincidence cannot yet be answered, several pathophysiological consequences of LPI can be defined as separate, such as links between the impact of low arginine levels on the function of vascular endothelium and brain nitric oxide metabolism, as well as hemophagocytic syndrome associated with the risk of vasculitis, thus accounting for the development of moyamoya vasculopathy.

PTP1B controls non-mitochondrial oxygen consumption by regulating RNF213 to promote tumour survival during hypoxia

Tumours exist in a hypoxic microenvironment and must limit excessive oxygen consumption. Hypoxia-inducible factor (HIF) controls mitochondrial oxygen consumption, but how/if tumours regulate non-mitochondrial oxygen consumption (NMOC) is unknown. Protein-tyrosine phosphatase-1B (PTP1B) is required for Her2/Neu-driven breast cancer (BC) in mice, although the underlying mechanism and human relevance remain unclear. We found that PTP1B-deficient HER2(+) xenografts have increased hypoxia, necrosis and impaired growth. In vitro, PTP1B deficiency sensitizes HER2(+) BC lines to hypoxia by increasing NMOC by α-KG-dependent dioxygenases (α-KGDDs). The moyamoya disease gene product RNF213, an E3 ligase, is negatively regulated by PTP1B in HER2(+) BC cells. RNF213 knockdown reverses the effects of PTP1B deficiency on α-KGDDs, NMOC and hypoxia-induced death of HER2(+) BC cells, and partially restores tumorigenicity. We conclude that PTP1B acts via RNF213 to suppress α-KGDD activity and NMOC. This PTP1B/RNF213/α-KGDD pathway is critical for survival of HER2(+) BC, and possibly other malignancies, in the hypoxic tumour microenvironment.

Occult progressive pulmonary arterial occlusion associated with right ventricular hypertension in patients with systemic arteriopathy

OBJECTIVES

Peripheral pulmonary artery stenosis (PPS) is a heterogeneous disease associated with numerous clinical or syndromic disorders including Williams syndrome. Previous studies focusing on patients with Williams syndrome have documented spontaneous improvement in branch pulmonary artery (PA) stenosis and right ventricular pressure. The goal of this study is to identify angiographic evidence of spontaneous occlusion or loss of segmental PAs in patients with PPS.

METHODS

Patients undergoing serial catheterization for PPS at Boston Children's Hospital between 1999 and 2014 were selected. Patients with structural heart disease such as tetralogy of Fallot, truncus arteriosus, transposition of the great arteries, or single ventricle were excluded. Hemodynamic data were extracted from catheterization reports, all available angiograms were reviewed, and evidence of segmental PA loss was documented based on defined angiographic criteria.

RESULTS

Forty-two patients were included in the study. Each patient underwent an average of 5 catheterizations over the 15-year study period. The average RV pressure at initial catheterization was near systemic levels. Evidence of segmental PA loss was present in 40% of patients. Almost 30% of patients with vessel loss demonstrated loss at their initial catheterization, and 65% of patients experienced loss of multiple vessels over time. Patients with vessel loss tended to be older at initial catheterization and have higher average RV pressures at their most recent catheterization than those without vessel loss.

CONCLUSIONS

Progressive segmental PA loss in patients with systemic arteriopathy and PPS has not been well described previously. In this cohort, segmental PA loss occurred in 40% of patients, resulting in persistently elevated PA pressures relative to patients who did not develop vessel loss. These findings highlight the importance of surveillance in this population of patients with systemic arteriopathy and severe PPS.

Clinical features, prothrombotic risk factors, and long-term follow-up of eight pediatric Moyamoya patients

Background and Purpose

The aim of this study was to elucidate the clinical features, prothrombotic risk factors, and outcome of pediatric Moyamoya patients.

Methods

Patients diagnosed with Moyamoya disease at a tertiary center between January 2000 and December 2006 were enrolled in this study. The clinical presentations, underlying diseases, prothrombotic risk factors, family history of thrombosis, radiological findings, treatment, and outcome of the patients were reviewed retrospectively.

Results

Eight patients with angiographically proven Moyamoya disease were identified, one of whom had neurofibromatosis type I and one had Down syndrome. The age at diagnosis varied between 19 months and 11 years (73.4±41.8 months, mean±SD). The follow-up period after diagnosis was 52.5±14.8 months. In six patients, the initial clinical presentation was hemiparesis. None of the patients had any identifiable prothrombotic factors. Despite medical and surgical treatment, three patients had recurrences and one died. Only two patients recovered without sequelae.

Conclusions

The value of prothrombotic risk factor evaluation appears to be limited in Moyamoya patients; the outcome for pediatric patients remains dismal.

Hypothermic cardiopulmonary bypass for minimally invasive mitral valve plasty in adult moyamoya disease

A 43-year-old man underwent minimally invasive mitral valve plasty of a flail mitral valve. Four years previously, he had been diagnosed with moyamoya disease (MMD) by cerebral magnetic resonance imaging/angiography findings. In MMD, risk factors for cerebral stroke include changes in arterial carbon dioxide partial pressure, blood pressure, and body temperature. And during cardiopulmonary bypass (CPB), these hemodynamic changes can be challenging. However, hypothermia during CPB can decrease cerebral oxygen consumption and have a cerebral protective effect. We performed a minimally invasive mitral valve plasty, using hypothermic CPB, in a patient with MMD, without any neurological deficits.

Moyamoya disease in early infancy: case report and literature review

Moyamoya disease is a progressive, occlusive, cerebrovascular arteriopathy, characterized by bilateral stenosis of the distal internal carotid arteries or branches, with the development of compensatory collateral vessels. It is infrequently reported during infancy. We describe a 2-month-old boy presenting with stroke secondary to moyamoya disease, successfully treated with revascularization surgery at age 3 months. To our knowledge, this report represents the youngest such patient. This case and a review of the literature regarding moyamoya disease during infancy suggest that these patients are at significant risk for further ischemic events and respond well to prompt revascularization surgery.

Moya moya disease in a child: a case report

We report a case of 8-year-old female child who was admitted at our hospital with complaints of transient ischemic attacks and left-sided hemiparesis. On MR angiography, the child was diagnosed to have Moya Moya disease. Moya Moya disease is a rare cause of cerebral stroke in children. The patient was treated conservatively and referred to a higher centre for specific neurosurgery. Neurosurgical revascularization process leads to favourable outcome.

Diagnosis and management of pediatric arterial ischemic stroke

Pediatric stroke is among the top 10 causes of death in children and an important cause of chronic morbidity, with an incidence of 3.3/100,000 children/year. Risk factors associated with stroke in children include cardiac diseases, hematologic and vascular disorders, and infection. Clinical presentation varies depending on age, underlying cause, and stroke location. Antithrombotics and anticoagulants are used in the treatment of pediatric stroke; however, there are no established guidelines for the use of these agents in children. In this article we review the cause, pathophysiology, clinical presentation, diagnosis, acute management, secondary prevention, and outcome of children with stroke. The approach to patients with sickle cell disease and Moyamoya disease is also discussed. Up to date studies to determine the optimal acute treatment of childhood stroke and secondary prevention and risk factor modification are critically needed.

Moyamoya disease: a clinical spectrum, literature review and case series from a tertiary care hospital in Pakistan

Background

Moyamoya is a rare cerebrovascular disease of unknown etiology. The data on moyamoya disease from Pakistan is sparse. We report a case series of 13 patients who presented with moyamoya disease to a tertiary care hospital in Pakistan with a national referral base.

Methods

We conducted a retrospective review of thirteen patients who presented to The Aga Khan University and diagnosed with "Moyamoya Disease" during the period 1988 – 2006. These patients were identified from existing hospital database via ICD-9 codes. A predesigned questionnaire containing information about clinical presentation, management and neuroimaging was administered to all identified patients.

Results

There were seven males and six females. Mean age at presentation was 16.5 years and a female predominance was found in the pediatric age group (n = 10, 71.4%). Stroke (n = 11, 84.2%) was the most common presentation with motor deficit being the universal cortical symptom. Fever was a common symptom in the lower age groups (n = 4, 51.7%). Cerebral Angiography and Magnetic Resonance Angiography showed bilateral involvement of the vessels in eleven patients while unilateral in two. Subarachnoid and interventricular haemorrhage appeared in 2(15.4%) adults. Twelve (92.3%) patients were discharged as independent with minor deficits regardless of therapeutic modality. Only three (23.0%) patients underwent surgery whereas the remaining were managed conservatively.

Conclusion

Physicians when dealing with childhood strokes and characteristic deficits in adult population should consider Moyamoya disease.

Predictors of cerebral arteriopathy in children with arterial ischemic stroke: results of the International Pediatric Stroke Study

BACKGROUND

Cerebral arteriopathies, including an idiopathic focal cerebral arteriopathy of childhood (FCA), are common in children with arterial ischemic stroke and strongly predictive of recurrence. To better understand these lesions, we measured predictors of arteriopathy within a large international series of children with arterial ischemic stroke.

METHODS AND RESULTS

Between January 2003 and July 2007, 30 centers within the International Pediatric Stroke Study enrolled 667 children (age, 29 days to 19 years) with arterial ischemic stroke and abstracted clinical and radiographic data. Cerebral arteriopathy and its subtypes were defined using published definitions; FCA was defined as cerebral arterial stenosis not attributed to specific diagnoses such as moyamoya, arterial dissection, vasculitis, or postvaricella angiopathy. We used multivariate logistic regression techniques to determine predictors of arteriopathy and FCA among those subjects who received vascular imaging. Of 667 subjects, 525 had known vascular imaging results, and 53% of those (n=277) had an arteriopathy. The most common arteriopathies were FCA (n=69, 25%), moyamoya (n=61, 22%), and arterial dissection (n=56, 20%). Predictors of arteriopathy include early school age (5 to 9 years), recent upper respiratory infections, and sickle cell disease, whereas prior cardiac disease and sepsis reduced the risk of arteriopathy. The only predictor of FCA was recent upper respiratory infection.

CONCLUSIONS

Arteriopathy is prevalent among children with arterial ischemic stroke, particularly those presenting in early school age, and those with a history of sickle cell disease. Recent upper respiratory infection predicted cerebral arteriopathy and FCA in particular, suggesting a possible role for infection in the pathogenesis of these lesions.

Moyamoya disease associated with midaortic syndrome

We report a 1-year-old girl who presented moyamoya disease associated with midaortic syndrome. She had been treated for cardiac failure and severe hypertension due to midaortic syndrome until she suffered seizure and repeated cerebral ischemic attack. Cerebral angiography revealed stenosis of the bilateral internal carotid artery at its terminal portion. She was successfully treated with encephaloduroarteriosynangiosis, and ischemic attack ceased postoperatively. This is the first report of moyamoya disease with midaortic syndrome. Although cerebral ischemic attack has been effectively managed by encephaloduroarteriosynangiosis, renovascular hypertension is still difficult to control.

Smith–Magenis syndrome and moyamoya disease in a patient with del(17)(p11.2p13.1)

Chromosomal rearrangements causing microdeletions and microduplications are a major cause of congenital malformation and mental retardation. Because they are not visible by routine chromosome analysis, high resolution whole-genome technologies are required for the detection and diagnosis of small chromosomal abnormalities. Recently, array-comparative genomic hybridization (aCGH) and multiplex ligation-dependent probe amplification (MLPA) have been useful tools for the identification and mapping of deletions and duplications at higher resolution and throughput. Smith-Magenis syndrome (SMS) is a multiple congenital anomalies/mental retardation syndrome caused by deletion or mutation of the retinoic acid induced 1 (RAI1) gene and is often associated with a chromosome 17p11.2 deletion. We report here on the clinical and molecular analysis of a 10-year-old girl with SMS and moyamoya disease (occlusion of the circle of Willis). We have employed a combination of aCGH, FISH, and MLPA to characterize an approximately 6.3 Mb deletion spanning chromosome region 17p11.2-p13.1 in this patient, with the proximal breakpoint within the RAI1 gene. Further, investigation of the genomic architecture at the breakpoint intervals of this large deletion documented the presence of palindromic repeat elements that could potentially form recombination substrates leading to unequal crossover.

Postmortem intracranial neuropathology in children following cardiac transplantation

At Loma Linda University Children's Hospital, the medical information of 405 pediatric patients who received orthotopic cardiac transplantation were reviewed. Of those who died (n=136), 86% (n=117) underwent postmortem examinations, and the brain was examined in 61% (n=82, male=39). The number and type of intracranial lesions present were compiled, and these were matched to underlying functional cardiac disease categories. Intracranial abnormalities were present in 87%. Infarct was the most common primary central nervous system pathology in hypoplastic left heart syndrome (41%) but was also observed frequently in children with obstructive lesions (37%), cyanotic disease (31%), or cardiac shunting (29%). Secondary findings included extraparenchymal hemorrhage in obstructive lesions (31%); hypoxic changes occurred in 15% of patients with cyanotic disease and in 14% of those with cardiac shunting. Thirty-three percent of children with restrictive lesions had no neuropathology reported. Postmortem examination brain weights were matched against age and sex norms, with 29% of females and 36% of males below two standard deviations. These findings revealed that intracranial pathology was present in the majority of transplanted children who underwent postmortem examination, and that infarctive changes constituted the most common neuropathologic abnormality. Additionally, a number of children had significantly reduced brain weight.

Anesthetic management of pial synangiosis and intracranial hemorrhage with a Fontan circulation

We report the case of a 11-year-old girl with Moyamoya syndrome, who had undergone staged-repair of tricuspid atresia to a Fontan circulation, scheduled to undergo bilateral pial synangiosis. Surgery for the first hemisphere was complicated by intracranial hemorrhage requiring an emergency craniotomy. The case highlights the importance of understanding Fontan physiology and its interrelationship with the cerebral circulation in the setting of cerebrovascular insufficiency and raised intracranial pressure.

Moyamoya disease complicated by life-threatening epistaxis: first report of a case

OBJECTIVE

Subacute haemorrhage is a common emergency in otorhinolaryngology. Rapid evaluation of the aetiology and localization is a precondition for suitable treatment. We demonstrate a rare case of primarily intractable epistaxis associated with occlusion of the circle of Willis (moyamoya disease).

PATIENT

A 38-year-old man presented with a 24-h history of recurrent epistaxis. Anamnesis revealed long-term anticoagulation after heart valve transplantation and arterial hypertension.

RESULTS

As a result of several re-bleedings after anterior nasal packing, a re-packing was followed by surgical treatment under general anaesthesia. Four days after discharge the patient presented to the intensive care unit with severe re-bleeding. After removal of a temporary Bellocq packing, interdisciplinary treatment was necessary. Emergency angiography revealed advanced moyamoya disease, with occlusion of both internal carotid arteries. The cerebral blood supply was sustained by an excessive collateral network originating from external carotid anastomoses. This complicated the endovascular treatment, which consisted of embolization of the infraorbital and maxillar arteries with liquid material and coils flanked by Bellocq packing. The patient was doing well at follow-up after 12 months.

CONCLUSION

Epistaxis complicating moyamoya disease is rare, and endovascular treatment is difficult due to the high risk of cerebral embolism. Malformations of the cerebral arteries should be considered in the differential diagnosis of intractable epistaxis.

Moyamoya angiopathy with dolichoectatic internal carotid arteries, patent ductus arteriosus and pupillary dysfunction: a new genetic syndrome?

We report on 2 children with moyamoya angiopathy and bilateral dolichoectatic internal carotid arteries in combination with iris hypoplasia with bilateral fixed dilated pupils and a history of patent ductus arteriosus. Both were symptomatic with moyamoya angiopathy and underwent bilateral extracranial-intracranial (EC-IC) bypass operations for cerebral revascularization. This is the first report on moyamoya angiopathy and bilateral dolichoectatic internal carotid arteries with simultaneous occurrence of ocular and cardiovascular malformations. There have been descriptions of cerebral vascular abnormalities in combination with either congenital heart disease or ocular abnormalities but not with both presenting together. The combination of these separate congenital developmental defects may not be purely coincidental: we propose that the 2 probands are affected with a not yet recognized clinical syndrome of probably genetic etiology.

Moyamoya disease presented with migrainelike headache in a 4-year-old girl

A 4-year-old girl was admitted to our department with the complaints of severe headache, nausea, vomiting, and photophobia. She had a 1-year history of migrainelike headache that occurred every 1 to 2 months. Her neurologic examination was normal, but T-weighted axial magnetic resonance imaging (MRI) of the brain showed flow void within the basal ganglia owing to parenchymal vascular collaterals. Magnetic resonance angiography and digital substraction carotid angiography showed both occlusion of the internal carotid artery in the supraclinoid portion and extensive parenchymal vascular collaterals. Because there was no evidence of risk factors for cerebral arterial occlusion and cerebral infarct or hemorrhage, she was diagnosed as having moyamoya disease. In any case of atypical migrainelike headache, a detailed investigation should be kept in mind to detect an underlying vascular disease such as moyamoya.

Arterial strokes in children

Pediatric stroke has received special attention in the recent literature. It is now recognized as an important cause of mortality and morbidity in pediatric population. Varied and poorly specific symptomatology as well as overlapping risk factors makes the diagnosis of stroke in childhood challenging. Therapy remains controversial. The use of anticoagulation and thrombolysis in the management of acute stroke in children has not been systematically studied. In this article, we discuss the natural history, investigation, and treatment of pediatric arterial hemorrhagic and ischemic strokes.

Risk factors for arterial ischemic stroke in children

Since early recurrence occurs in at least 10% of patients presenting with their first stroke in childhood in the reported series, the search for modifiable risk factors should be a priority. Risk factors for stroke in adults include hypertension, diabetes, and smoking, as well as cardiac disease and sickle cell anemia; asymptomatic cerebrovascular disease and transient ischemic events may predict stroke in this age group. The investigation of a child with a stroke has traditionally focused on finding a single cause rather than looking for risk factors to which the patient may be exposed life long. Approximately half of children presenting with stroke have a known predisposing condition, but some have unexpected pathologies such as primary cerebrovascular disease associated with congenital heart anomalies, or may have modifiable risk factors such as hypertension associated with sickle cell disease. The literature on children presenting with initially unexplained (cryptogenic) stroke suggests that there is a daunting list of possible causes, but since the series have mainly been small, it has been difficult to evaluate the relative importance of the reported associations. This paper reviews the literature on congenital, genetic, and acquired risk factors for stroke in childhood, and includes data from the large series of patients seen at Great Ormond Street Hospital over the past 10 years. The majority have arteriographic abnormalities and there is little evidence for asymptomatic cardiac disease. Genetic predisposition, trauma, infection, and nutritional deficiencies appear to be important, although case-control studies will be required to prove causation. Appropriate screening for modifiable risk factors may lead to prevention of recurrence in some patients. In the long term, an understanding of the multiple etiologies of childhood cerebrovascular disease and ischemic stroke may lead to primary prevention in this age group, and perhaps in adults.

Central deafness in a young child with Moyamoya disease: paternal linkage in a Caucasian family: two case reports and a review of the literature

A case of 'central deafness' is presented in a 3-year-old male Caucasian child with Moyamoya disease (MMD); a rare, progressive and occlusive cerebrovascular disorder predominantly affecting the carotid artery system. Documentation of normal peripheral auditory function and brainstem pathway integrity is provided by acoustic admittance, otoacoustic emission and brainstem auditory evoked potential measurements. The lack of behavioral response to sound, and absent middle and long latency auditory evoked potentials suggest thalamo-cortical dysfunction. Magnetic resonance imaging showed diffuse ischemic damage in subcortical white matter including areas of the temporal lobes. In addition, there were multiple and focal cortical infarctions in both cerebral hemispheres, focused primarily in the frontal, parietal and temporal areas. Taken together, these structural and functional abnormalities in addition to severely delayed speech and language development are consistent with the diagnosis of central deafness and suggest a disconnection between higher brainstem and cortical auditory areas. The child's father also has MMD, but was diagnosed only recently. The presence of paternal linkage is informative since it rules out x-linked recessive and maternal inheritance. To our knowledge, this represents the first documented case of paternal linkage in MMD with central deafness in a Caucasian child with no apparent Japanese ancestry. Herein, we focus on central auditory dysfunction and consider how lesion-induced changes have contributed to a deficit in basic auditory responsiveness, including a severe disturbance in receptive and expressive auditory-based speech and language skills.