Use of a calcium channel blocker (nicardipine HCl) in the treatment of childhood moyamoya disease

Cerebral Vasculopathy in Children with Neurofibromatosis Type 1

Cerebrovascular abnormalities are a severe and often underrecognized complication of childhood neurofibromatosis type 1 (NF1). There are no prospective studies of cerebral vasculopathy in NF1; thus, the estimated frequency of vasculopathy varies between studies. The data is difficult to interpret due to the retrospective data collection and variability in whether imaging is done based on screening/surveillance or due to acute neurologic symptoms. The prevalent NF1-associated cerebral vasculopathy is moyamoya syndrome (MMS). Vascular changes can present without symptoms or with acute TIA or stroke-like symptoms or a range of progressive neurologic deficits. Advanced imaging may enhance sensitivity of neuroimaging in children. Medical and/or surgical interventions may prevent short- and long-term complications. Challenges for establishment of a screening protocol for cerebral vasculopathy in children with NF1 include the relatively large number of patients with NF1, the potential need for sedation to achieve quality imaging and the broad age range at time of detection for cerebral vascular changes. The goal of this review is to present the epidemiology, clinical presentation, imaging features and medical/surgical management of cerebral arteriopathies in children with NF1.

Idiopathic steno-occlusive disease with bilateral internal carotid artery occlusion: A Case Report

BACKGROUND

Moyamoya disease (MMD) is a rare cause of acute stroke and transient ischemic attacks in children. We described clinical, diagnostic features and follow-ups of a young child with acute stroke.

CASE SUMMARY

We report a 4-year-old girl with left hemiparesis after an acute ischemic stroke. Her history was also significant for repeated left or right focal motor seizures, generalized tonic-clonic convulsions and transient ischemic attacks. Her magnetic resonance imaging and computed tomography (CT) of the brain and magnetic resonance angiography, CT angiography and venography on the cerebral vessels revealed evidence of bilateral fronto-parietal ischemic infarctions, occlusion of the right and left internal carotid arteries started at its bifurcation and non-visualization of right and left anterior and middle cerebral arteries. There was evidence of progression in angiography manifested as development of collaterals from the basal perforating vessels, increase in the extent of large intracranial arterial stenosis/occlusion and extensive collateral circulation with predominance from the posterior circulation. Physical and neurological evaluation and comprehensive laboratory investigations excluded an obvious comorbid disease or risk factor for the child’s condition. The diagnosis of MMD was highly suggested as a cause of the child’s steno-occlusive condition. She was treated symptomatically with levetiracetam, an antiepileptic medication. Aspirin was prescribed for secondary prevention. Her clinical manifestations were improved during the three years of follow-up. Revascularization surgery was postponed.

CONCLUSION

Up to our knowledge, this is the first report for MMD in a child in our country. The clinical improvement and the stabilization of the child’s condition over the 3 years of follow-up could be attributed to the rapid and extensive recruitment of collaterals and absence of risk factors or comorbidities. Revascularization surgery is highly recommended.

Postoperative incidence of seizure and cerebral infarction in pediatric patients with epileptic type moyamoya disease: a meta-analysis of single rate

Background

Surgery is a conventional mature treatment for moyamoya disease (MMD). However, whether surgery is also an effective therapy for epileptic type MMD has seldom been investigated systematically. The study aims to summarize the pooled postoperative incidence of seizure and cerebral infarction in pediatric patients with epileptic type moyamoya disease.

Method

The study was a systematic review and critical appraisal with a meta-analysis of cohort studies, both prospective and retrospective. Studies were identified by a computerized search of PubMed, Embase, Web of Science, Wanfang, and CNKI databases. In a literature search, a total of 7 cohort studies were identified. The I²statistic was used to quantify heterogeneity. A fixed-effect model was used to synthesize the results. The linear regression test of funnel plot asymmetry was used to estimate the potential publication bias.

Results

The pooled estimated postoperative incidence of seizure in pediatric patients with epileptic type moyamoya disease was 23.44%. The pooled estimated postoperative incidence of cerebral infarction in pediatric patients with epileptic type moyamoya disease was 9.12%. Low substantial heterogeneity and potential publication bias were present.

Conclusions

Evidence from this study suggests that the postoperative incidence of seizure and cerebral infarction is relatively low. Surgery is an effective and secure therapy for pediatric patients with epileptic type moyamoya disease.

Peek through the smoke: a report of moyamoya disease in a 32-year-old female patient presenting with ischaemic stroke

Moyamoya disease is a vasculopathy causing chronic progressive stenosis and occlusion of the large arteries of the circle of Willis that could lead to brain ischaemia. The condition may also present with haemorrhagic strokes. This is a case report of moyamoya disease in a 32-year-old woman presenting with ischaemic stroke. The report describes her inpatient stay and investigations and findings.The report reviews the main aspects of moyamoya disease definition, epidemiology, clinical features, diagnosis, classification and treatment. This case is interesting because her first presentation occurred after 3 months of her second delivery. Whether the different physiological stresses of pregnancy, child birth and puerperium have had some effect in accelerating the pathogenesis of her moyamoya disease remains unknown. ¹.

Research Progress of Moyamoya Disease in Children

During the onset of Moyamoya disease (MMD), progressive occlusion occurs at the end of the intracranial internal carotid artery, and compensatory net-like abnormal vessels develop in the skull base, generating the corresponding clinical symptoms. MMD can affect both children and adults, but MMD in pediatric patients exhibits distinct clinical features, and the treatment prognoses are different from adult patients. Children are the group at highest risk for MMD. In children, the disease mainly manifests as ischemia, while bleeding is the primary symptom in adults. The pathogenesis of MMD in children is still unknown, and some factors are distinct from those in adults. MMD in children could result in progressive, irreversible nerve functional impairment, and an earlier the onset corresponds to a worse prognosis. Therefore, active treatment at an early stage is highly recommended. The treatment methods for MMD in children mainly include indirect and direct surgeries. Indirect surgeries mainly include multiple burr-hole surgery (MBHS), encephalomyosynangiosis (EMS), and encephaloduroarteriosynangiosis (EDAS); direct surgeries mainly include intra- and extracranial vascular reconstructions that primarily consist of superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. Indirect surgery, as a treatment for MMD in children, has shown a certain level of efficacy. However, a standard treatment approach should combine both indirect and direct procedures. Compared to MMD in adults, the treatment and prognosis of MMD in children has higher clinical significance. If the treatment is adequate, a satisfactory outcome is often achieved.

Pharmacology in childhood arterial ischemic stroke

In recent years, there has been increasing recognition of the impact of childhood stroke and interest in the role of drugs in the acute, chronic, and prophylactic management of this condition. Most treatment strategies are based on studies in adults with stroke, and the relative infrequency of stroke and the heterogeneity of etiologies in childhood compared with adults present significant challenges in study design for childhood stroke studies. The presence of thrombophilia has been associated with stroke in children, strengthening the concept that antithrombotic, antiplatelet, and even thrombolytic agents have a role in stroke treatment and prevention. There are several potential roles for drugs in the treatment of childhood stroke including hyperacute therapy, antithrombotic medication, antiplatelet medication, and disease-specific medications. Herein, we review the use and rationale of these medications in childhood arterial ischemic stroke.

Moyamoya disease presented as a case of hemiplegic migraine

Moyamoya disease is a rare cerebral vasculopathy characterised by progressive narrowing of the major intracranial vessels and development of collateral vessels. Clinically, it presents with cerebral ischaemic or haemorrhagic events, with eventual severe morbidity and mortality. A 10-year-old girl presented with episodic vascular headache and transient left sided hemiparesis, which persisted for a few hours and was clinically labelled as sporadic hemiplegic migraine according to International Headache Society criteria. We investigated all possible causes of unusual headache. Cerebral digital subtraction angiogram was carried out and moyamoya disease was finally diagnosed.

Cerebral oxygen saturation monitoring for off-pump coronary bypass graft surgery with Moyamoya disease: A case report

We report a case using cerebral oxygen saturation (rCbO2) for off-pump coronary artery bypass graft (OPCAB) surgery in a patient with co-existing Moyamoya disease. The rCbO2 with the routine monitoring for OPCAB surgery were monitored intraoperatively. In spite of infusing nimodipine (0.2 microgram/kg/min) and maintaining the end-tidal CO2 tension at 35-40 mmHg, a sudden reduction in the right-side rCbO2 from the base line value of 70-80%/78-83% (Left/Right) to 70-72%/65-70% was developed during the harvesting of the vascular graft. We increased the rate of phenylephrine infusion to increase systemic and cerebral perfusion pressure, and both rCbO2 values were elevated to 80%/70% within 3 minutes. However, the preferential reduction in the right-side rCbO2 compared with the left-side value was not corrected. While suspecting cerebral ischemia due to cerebral vascular spasm, we administered nimodipine 2 mg bolus and increased infusion rate to 0.5 microgram/kg/min. Finally, the preferential rCbO2 reduction in the right-side was corrected and both rCbO2 reached 84%/91%. We concluded rCbO2 monitoring is useful for detecting an intraoperative episode of cerebral ischemia and maintaining the optimal cerebral perfusion during OPCAB surgery with Moyamoya disease.

Nursing issues in caring for children with moyamoya vasculopathy and their families

Moyamoya vasculopathy is a rare, progressive neurovascular condition that may cause recurrent transient ischemic attacks, ischemic strokes, hemorrhagic strokes, or neurologic decline in children. Children with moyamoya disease have no clear contributing etiology, but children with moyamoya syndrome have contributory diagnoses such as Down syndrome or neurofibromatosis. The concerns and lived experiences of children affected by this disease and their families have not been well explored or addressed in the nursing literature. Nurses who understand this lived experience increase their own knowledge of the disease so they can manage the complex medical issues, educate families about the disease, and provide emotional support.

Stroke in Childhood

BACKGROUND

Childhood stroke is increasingly recognized as an important cause of morbidity and mortality. Risk factors for stroke in childhood are different than those traditionally seen in adults.

REVIEW SUMMARY

This review summarizes, in brief, the epidemiology, risk factors, evaluation, treatment, outcome, and recurrence risk of children with arterial ischemic stroke (AIS). Areas of controversy and those that require further study are highlighted. Tables summarizing important points of the history, physical examination, and diagnostic evaluation of AIS are provided.

CONCLUSIONS

Children with stroke should be carefully evaluated for risk factors and possible etiology of stroke. At the present time, treatment is based upon extrapolation from the adult literature and expert opinion, as no evidence-based guidelines exist, except in sickle cell anemia. International, multicenter trials are beginning and should provide some answers over the next few years.

Moyamoya disease in adults: the role of cerebral revascularization

Moyamoya disease is a disorder characterized by bilateral progressive steno-occlusion of the terminal internal carotid arteries with associated development of a fragile network of basal collateral vessels. It most commonly presents in children, but is also frequently seen in adults, especially in the third or fourth decade of life. Adults afflicted with this disease have very different clinical characteristics as compared with children. For example, adults more commonly present with hemorrhage than cerebral ischemia, while children present with cerebral ischemia nearly 75% of the time and very rarely present with hemorrhage. This significantly impacts treatment considerations for the adult-onset moyamoya patient, as cerebral revascularization, though well accepted in the context of cerebral ischemia, is relatively controversial for the prevention of rehemorrhage. The purpose of this article is to review the pertinent general features of moyamoya disease, examine the clinical characteristics associated with the adult-onset form of this disease, and provide a detailed discussion regarding the indications, operative techniques, and outcomes of direct and indirect revascularization surgical procedures.

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.

Coronary collateralization: determinants of adequate distal vessel filling after arterial occlusion

BACKGROUND

The protective effect of collateral vessels in coronary artery disease (CAD) is well established. Little is known, however, about factors that influence collateral formation.

METHODS

We studied the coronary angiograms of 200 consecutive patients with single-vessel coronary artery occlusion. Patients were excluded if obstructive stenoses were present in other vessels or if prior revascularization had been undertaken. Collateral circulation to the occluded artery was graded as 'poor' (no or incomplete filling) or 'rich' (complete filling). Patient characteristics, including mode of presentation, medications and CAD risk factors, were assessed.

RESULTS

Positive univariate correlates of rich collaterals included increasing age [odds ratio (OR) 1.03, P = 0.016], 'statin' use (OR 2.50, P = 0.005), nitrate use (OR 1.96, P = 0.034), calcium-channel blocker (CCB) use (OR 4.07, P < 0.001), presentation with stable angina (OR 2.34, P = 0.006), longer time since diagnosis of CAD (OR 1.12, P = 0.002) and history of hyperlipidemia (OR 3.55, P < 0.001). Significantly poorer collateralization was observed in the setting of acute myocardial infarction (MI) (OR 0.23, P < 0.001), diabetes mellitus (OR 0.33, P = 0.003), impaired left ventricular function (OR 0.64, P = 0.015) and occlusion of the left anterior descending coronary artery (LAD) (OR 0.28, P < 0.001). On multivariate analysis, rich collateralization was associated with hyperlipidemia (P = 0.003) and CCB use (P = 0.028). Independent predictors of poor collaterals were presence of diabetes (P < 0.001), LAD occlusion (P = 0.001) and presentation with acute MI (P = 0.017).

CONCLUSION

Diabetes mellitus, occlusion of the LAD and presentation with acute MI are independently associated with poor distal vessel collateralization, whereas hyperlipidemia and use of CCBs are associated with rich collateralization. Factors determining coronary collateral formation may in turn influence outcomes after coronary artery occlusion.

Protective effect of nimodipine on behavior and white matter of rats with hydrocephalus

OBJECT

Hydrocephalus, a pathological dilation of the ventricles of the brain, causes damage to periventricular white matter, at least in part, through chronic ischemia. The authors tested the hypothesis that treatment with nimodipine, an L-type calcium channel-blocking agent with demonstrated efficacy in a range of cerebral ischemic disorders, would ameliorate the adverse effects of experimental hydrocephalus.

METHODS

Hydrocephalus was induced in 3-week-old rats by injection of kaolin into the cisterna magna. The rats were treated by continuous administration of nimodipine or control vehicle for 2 weeks, beginning 2 weeks after induction of hydrocephalus. During the treatment period, the animals underwent repeated tests of motor and cognitive behavior. At the end of the treatment period, the rat brains were analyzed by histopathological and biochemical means. Nimodipine treatment prevented the declines in motor and cognitive behavior that were observed in untreated control rats. During the treatment period, ventricular enlargement, determined by magnetic resonance imaging, was equal in the two groups, although the corpus callosum was thicker in the treated rats. Myelin content in white matter and synaptophysin content in gray matter, an indicator of synapses, did not differ.

CONCLUSIONS

The protective effect of nimodipine is most likely based on improved blood flow, although prevention of calcium influx-mediated proteolytic processes in axons cannot be excluded. Adjunctive pharmacological therapy may be beneficial to patients with hydrocephalus.

The feasibility of intracarotid adenosine for the manipulation of human cerebrovascular resistance

To assess the feasibility of manipulating human cerebrovascular resistance with adenosine, we measured cerebral blood flow (CBF) by determining the initial slope (IS) of tracer washout 20-80 s after intracarotid 133Xe injection (standard IS) during sequential 3-min intracarotid infusions of (a) saline; (b) adenosine 1.2-mg bolus followed by an infusion of 1 mg/min (bolus + infusion); (c) saline; and (d) nicardipine (0.1 mg/min). During 133Xe washout, adenosine caused a rapidly clearing compartment. Therefore, tracer washout was also analyzed 5-25 s after injection (early IS). Nicardipine (n = 8) increased both standard IS (from 39+/-12 to 53+/-16 mL 100g.min(-1); P < 0.005) and early IS (from 40+/-9 to 55+/-20 arbitrary units; P < 0.02) to a similar degree. Adenosine bolus + infusion increased early IS (from 33+/-6 to 82+/-43 arbitrary units; P < 0.02) but did not increase standard IS (from 41+/-12 to 43 +/-16 mL 100g(-1) min(-1)). Standard and early IS values were then determined before and after adenosine delivered either by infusion alone (2 mg/min for 3 min, n = 5) or bolus alone (2 mg in 1 s, n = 3). Neither standard nor early IS changed after adenosine infusion alone. Early IS increased after adenosine bolus alone. Increase in early IS, but not standard IS, suggests a transient (<30 s) increase in CBF.

IMPLICATIONS

Intracarotid adenosine, in the 1- to 2-mg dose range, may cause a transient, but not a sustained, increase in cerebral blood flow. Intracarotid adenosine in such a dose range does not seem to be an appropriate drug for sustained manipulation of cerebrovascular resistance.

Clinical features of moyamoya disease in the United States

BACKGROUND AND PURPOSE

We report the clinical features and longitudinal outcome of the largest cohort of patients with moyamoya disease described from a single institution in the western hemisphere. Moyamoya disease in Asia usually presents with ischemic stroke in children and intracranial hemorrhage in adults.

METHODS

Our study population included all patients with moyamoya disease evaluated at a university hospital in Houston, Texas from 1985 through 1995 (n = 35). We used Kaplan-Meier methods to estimate individual and hemispheric stroke risk by treatment status (medical versus surgical). Predictors of neurological outcome were assessed.

RESULTS

The ethnic background of our patients was representative of the general population in Texas. The mean age at diagnosis was 32 years (range, 6 to 59 years). Ischemic stroke or transient ischemic attack was the predominant initial symptom in both adults and children. Of the 6 patients with intracranial hemorrhage, 5 had an intraventricular site of hemorrhage. The crude stroke recurrence rate was 10.3% per year in 116 patient-years of follow-up. Twenty patients underwent surgical revascularization, the most common procedure being encephaloduroarteriosynangiosis. The 5-year risk of ipsilateral stroke after synangiosis was 15%, compared with 20% for medical treatment and 22% overall for surgery.

CONCLUSIONS

Our observations indicate that moyamoya disease may have a different clinical expression in the United States than in Asia, and may demonstrate a trend toward a lower stroke recurrence rate and better functional outcome after synangiosis.

A survey of moyamoya disease in Hawaii

Moyamoya disease (MMD) is a rare entity in the US with a few retrospective series and sporadic cases reported in the US and North America. Although it is known that MMD exists in all races, there is a predilection for people of Asian origin. Because of the relatively high percentage of Asians living in Hawaii, it was hypothesized that the estimated prevalence of MMD would be higher in Hawaii than the remaining US. All practicing neurologists, neurosurgeons, neuroradiologists and major hospitals in Hawaii were surveyed for MMD patients treated during the past 10 years. Medical records and angiograms (when available) were reviewed and the diagnostic guidelines for MMD from the Ministry of Health and Welfare of Japan applied. There were 53 records reviewed in 42 patients; 21 fulfilled the criteria for definite Moyamoya disease which were the focus of this study. In Hawaii, the prevalence of MMD was higher in patients of Japanese descent compared to Caucasians (P = 0.012) and higher than in the remaining US (P < 0.001). Non-Japanese Asians and Pacific Islanders had a higher incidence of MMD than Caucasians that was not statistically significant. There was no difference in MMD among Japanese living in Hawaii or Japan. Males had an equal percentage of hemorrhage and infarcts; females tended to have a higher incidence of ischemic events rather than hemorrhage. Age and sex distribution of our series were similar to larger reported MMD studies. Our results suggest that: (1) Moyamoya disease in Hawaii has a higher incidence and prevalence than the rest of the US, largely due to the larger percentage of Asians, particularly Japanese, living in Hawaii; and (2) genetic rather than environmental factors may explain the increased MMD in Hawaii.