Moyamoya Disease Epidemiology outside of Asia

Moyamoya Disease Epidemiology outside of Asia

Studies from outside of Asia are rare. In Washington state and California, the incidence of MMD was reported to be 0.086/100,000 based on 298 patients. The incidence was the highest in Asians, followed by Blacks, Whites, and Hispanics. The incidence in Asian Americans was 4.6 times higher than that in Whites. Female preponderance was also noted 1).

African-Americans had an earlier disease onset with a median age of 18. However, a more recent study based on the Nationwide Inpatient Sample database reported that MMD appears to be distributed among the races according to their relative proportions in the USA population 2).

From 2005 to 2008, there were an estimated 7,473 (2,236 pediatric and 5,237 adult) patients admitted with a diagnosis of MMD in the USA. MMD patients were most frequently Caucasians. Overall, ischemic stroke was the most common reason for admission in both children and adults. Hemorrhagic stroke was more frequent in adults compared with children, and there was a bimodal age distribution with peaks in the first and fourth decades of life. Female-to-male ratio was 2.2. Thus, MMD in the USA does not seem to differ from East Asian MMD.


The incidence of Moyamoya disease (MMD) in Europe is not well known. In those affected, the risk of brain hemorrhage is considered low. A study of Birkeland et al. aimed to investigate the incidence and clinical presentation of MMD in the Danish population.

Eligible patients were identified in the Danish National Patient Register from 1994 to 2017. They collected clinical and radiological data from individual patient records from neurological, neurosurgical, and pediatric units across Denmark. The diagnosis was validated according to established criteria. They also extracted basic demographic data on the cohort from the Danish Civil Registration System.

A total of 52 patients fulfilled the diagnostic criteria for MMD. Most cases were native Danes and only 15% of cases had an East Asian background. The ratio of female to male patients was 1.8, and the incidence had two peaks: one in childhood and another in young middle age. Until 2007, MMD was only diagnosed sporadically. From 2008 onwards, the incidence rate was 0.07 per 100 000 person-years (95% confidence interval 0.05-0.09 per 100 000 person-years). The most common mode of presentation was ischemic stroke (33%), followed by hemorrhage (23%), headache (17%), and transient ischemic attack (14%).

MMD is rare in Denmark, but associated with a considerable risk of hemorrhage. Thus, MMD should be considered in the workup for ischemic as well as hemorrhagic stroke in children and middle-aged Caucasian3).

References

1)

Uchino K, Johnston SC, Becker KJ, Tirschwell DL. Moyamoya disease in Washington State and California. Neurology. 2005;65(6):956-958. doi:10.1212/01.wnl.0000176066.33797.82
2)

Kainth D, Chaudhry SA, Kainth H, Suri FK, Qureshi AI. Epidemiological and clinical features of moyamoya disease in the USA. Neuroepidemiology. 2013;40(4):282-287. doi:10.1159/000345957
3)

Birkeland P, Tharmabalan V, Lauritsen J, Ganesan V, Bjarkam CR, von Weitzel-Mudersbach P. Moyamoya disease in a european setting: A danish population-based study [published online ahead of print, 2020 Jul 15]. Eur J Neurol. 2020;10.1111/ene.14439. doi:10.1111/ene.14439

Moyamoya disease outcome

Moyamoya disease outcome

The disorder can lead to negative mood and stress, which, left unresolved, may increase adverse health outcomes. yang et al. conducted a cross-sectional survey to examine the stress and mood of adults with moyamoya disease. Participants were recruited at a university hospital in SeoulKorea. Data were collected through questionnaires and review of participants’ electronic medical records. A total of 109 adult patients participated. Significant correlations were found between perceived stress, anxiety, and depression. Adults with moyamoya disease experience anxiety, depression, and stress-related to the risk of cerebral hemorrhage or ischemia, similar to patients with other cerebrovascular diseases. If uncontrolled, negative mood and stress can cause adverse health outcomes. Health professionals caring for patients with moyamoya disease should carefully observe patients’ stress and mood and develop interventions tailored to stages of the disease to help patients manage stress and mood. The study results provide baseline information for understanding the level of and the factors associated with stress and mood 1).


Pediatric Moyamoya disease patients have greater patency and a greater ability to establish good leptomeningeal collateral circulation (LMC) status than adult patients, and poor LMC status has a strong correlation with severe clinical symptoms and poor postoperative outcomes. LMC status may be an important factor in the differences in clinical characteristics and prognosis between pediatric and adult MMD patients 2).


Recurrent stroke after surgical revascularization is still a big issue for moyamoya disease (MMD).

Female, left-sided surgery and edematous lesion were independent risk factors for postoperative TNEs; the left-sided surgery and edematous lesion were also independently associated with the severity of TNE. Although patients with postoperative TNEs had worse neurological status during the perioperative period, postoperative TNEs had no associations with worse mRS score at the time of discharge 3).


The outcome following surgery is very difficult to judge, and there is no standardised measurement to assess it. It is therefore important to know which approach for such patient is adequate.

Comparing to patients with acute idiopathic primary intraventricular hemorrhage (PIVH), patients with acute MMD-related PIVH have younger age, lower blood pressure, and better renal function. Moreover, patients with acute MMD-related PIVH have lower short-term mortality 4).


Sundaram et al., compared the long-term outcome of moyamoya patients treated conservatively to those who underwent RS.

A study population included all patients with moyamoya disease/syndrome from 2002 to 2012. The demographic, clinical characteristic and imaging details were reviewed. The outcome was obtained prospectively.

Of the 36 patients, 26 (72.2%) had MMD and 10 (27.8%) had moyamoya syndrome. The median age at onset of symptoms was 17.5 years (range, 10 months-55 years). Fifteen patients belonged to pediatric group and 21 were adults. All the pediatric patients had ischemic events at onset and 10 (47.6%) of the adults presented with hemorrhage. Twenty (55.6%) patients received conservative treatment and 16 (44.4%) underwent revascularization procedures. The median duration of follow-up was 28 months (range, 3-90 months). Three (18%) of the surgically treated patients had recurrent ischemic events on follow-up, but none of the conservatively treated patients had events. An excellent outcome (Modified Rankin Scale of ≤2) was seen in 12 (75%) surgically treated and 16 (94%) conservatively treated patients (p=0.17).

Compared to East Asians, our patients had a lower stroke recurrence rate and good functional outcome even with conservative treatment. Future studies should focus on clinical and imaging predictors of progression to select moyamoya patients for RS 5).

References

1)

Yang YS, Ryu GW, Yeom I, Shim KW, Choi M. Stress and Mood of Adults with Moyamoya Disease: A Cross-Sectional Study. Nurs Health Sci. 2020 Apr 26. doi: 10.1111/nhs.12729. [Epub ahead of print] PubMed PMID: 32336006.
2)

Liu ZW, Han C, Wang H, Zhang Q, Li SJ, Bao XY, Zhang ZS, Duan L. Clinical characteristics and leptomeningeal collateral status in pediatric and adult patients with ischemic moyamoya disease. CNS Neurosci Ther. 2020 Jan;26(1):14-20. doi: 10.1111/cns.13130. Epub 2019 Apr 13. PubMed PMID: 31875482.
3)

Lu J, Zhao Y, Ma L, Chen Y, Li M, Chen X, Ye X, Wang R, Zhao Y. Predictors and clinical features of transient neurological events after combined bypass revascularization for moyamoya disease. Clin Neurol Neurosurg. 2019 Aug 29;186:105505. doi: 10.1016/j.clineuro.2019.105505. [Epub ahead of print] PubMed PMID: 31622898.
4)

Yu Z, Guo R, Zheng J, Li M, Wen D, Li H, You C, Ma L. Comparison of acute moyamoya disease-related and idiopathic primary intraventricular hemorrhage in adult patients. World Neurosurg. 2019 Jan 24. pii: S1878-8750(19)30167-6. doi: 10.1016/j.wneu.2019.01.070. [Epub ahead of print] PubMed PMID: 30685378.
5)

Sundaram S, Sylaja PN, Menon G, Sudhir J, Jayadevan ER, Sukumaran S, Sreedharan SE, Sarma S. Moyamoya disease: a comparison of long term outcome of conservative and surgical treatment in India. J Neurol Sci. 2014 Jan 15;336(1-2):99-102. doi: 10.1016/j.jns.2013.10.014. Epub 2013 Oct 16. PubMed PMID: 24183032.

Moyamoya Disease Diagnosis

Moyamoya Disease Diagnosis

Diagnosis of Moyamoya disease requires bilateral symmetrical stenosis or occlusion of the terminal portion of the internal carotid arterys (ICA)s as well as the presence of dilated collateral vessels at the base of the brain 1). (If unilateral, the diagnosis is considered questionable, 2) and these cases may progress to bilateral involvement).

Other characteristic findings include:

1. stenosis/occlusion starting at the termination of ICA and at origins of ACA and MCA

2. abnormal vascular network in the region of BG (intraparenchymal anastomosis).

3. transdural anastomosis(rete mirabile), AKA “vault moyamoya.”Contributing arteries: anterior falcial, middle meningeal, ethmoidal, occipital, tentorial, STA

4. moyamoya collaterals may also form from the internal maxillary artery via ethmoid sinus to the forebrain in the frontobasal region.

CT

Work-up in suspected cases typically begins with a non-enhanced head CT. Up to 40% of ischemic cases have normal CT. Low-density areas (LDAs) may be seen, usually confined to cortical and subcortical areas (unlike atherosclerotic disease or acute infantile hemiplegia which tend to have LDAs in basal ganglia as well). LDAs tend to be multiple and bilateral, especially in the PCA distribution (poor collaterals), and are more common in children.

MRI

MRA usually discloses the stenosis or occlusion of the ICA. Moyamoya vessels appear as flow voids on MRI (especially in basal ganglia) and a fine network of vessels on MRA and are demonstrated better in children than adults. Parenchymal ischemic changes are commonly shown, usually in watershed areas.

MRI images show:

1) diminished blood flow in the internal carotid artery (ICA) and the middle cerebral artery (MCA) and anterior cerebral artery (ACA) and 2) prominent collateral blood flow at the base of the brain. To confirm the diagnosis of moyamoya disease, an angiogram is typically required.

Diagnostic criteria of definitive moyamoya disease include all of the following items based on the conventional angiographic findings.

(1) Stenosis or occlusion of the terminal portion of the intracranial ICA or proximal portions of the anterior cerebral artery (ACA) and/or the middle cerebral artery (MCA).

(2) Development of abnormal vascular networks near the occlusive or stenotic lesions in the arterial phase.

(3) Bilateral lesion 3).

Results demonstrate distinct alterations in the temporal correlations of low-frequency BOLD signals, predominantly in resting-state networks in moyamoya disease. Additionally, Resting state functional magnetic resonance imaging (rs-fMRI) measures were associated with ischemic motor-related symptoms and cognitive performance in the patients. Thus, rs-fMRI may offer a useful non-invasive method of acquiring additional information beyond cerebral perfusion as part of clinical investigations in patients with moyamoya disease 4).


Territorial arterial spin labeling (t-ASL) could reveal comprehensive Moyamoya disease (MMD) cerebral blood perfusion and the vivid perfusion territory shifts fed by the unilateral ICA and ECA and bilateral vertebral arterys (VAs) in a noninvasive, straightforward, nonradioactive, and nonenhanced manner. 3D Time of flight magnetic resonance angiography (3D-TOF-MRA) could subdivide t-ASL perfusion territory shifts according to their shunt arteries. A perfusion territory shift attributable to the secondary collaterals is a potential independent risk factor for preoperative hemorrhage in MMD patients. A perfusion territory shift fed by the primary collaterals may not have a strong effect on preoperative hemorrhage in MMD patients. These findings make the combined modalities of t-ASL and 3D-TOF-MRA a feasible tool for MMD disease assessment, management, and surgical strategy planning 5).

Angiography

In addition to helping to establish the diagnosis, angiography also identifies suitable vessels for revascularization procedures and unearths associated aneurysms. The angiography-related complication rate is higher than with atherosclerotic occlusive disease. Avoid dehydration prior to and hypotension during the procedure. Six angiographic stages of MMD are described by Suzuki and Takaku 6) that tend to progress up until adolescence and stabilize by age 20.

1 stenosis of suprasellar ICA, usually bilateral

2 development of moyamoya vessels at the base of the brain; ACA MCA & PCA dilated

3 increasing ICA stenosis & prominence of moya-moya vessels (most cases diagnosed at this stage); maximal basal moyamoya

4 entire circle of Willis and PCAs occluded, extracranial collaterals start to appear, moyamoya vessels begin to diminish

5 further progression of stage 4

6 complete absence of moyamoya vessels and major cerebral arteries.

EEG

Non-specific in the adult. Juvenile cases: high-voltage slow waves may be seen at rest, predominantly in the occipital and frontal lobes. Hyperventilation produces a normal buildup of monophasic slow waves (delta-bursts) that return to normal 20–60 seconds after hyperventilation. In >50%of cases, after or sometimes continuous with buildup is a second phase of slow waves (this characteristic finding is called “rebuild up”) which are more irregular and slower than the earlier waves, and usually, normalize in ≤10 minutes 7).

Cerebral blood flow (CBF) studies

CBF is decreased in children with MMD, but relatively normal in adults. There is a shift of CBF from the frontal to the occipital lobes 8) probably reflecting the increasing dependency of CBF on the posterior circulation. Children with MMD have impaired autoregulation of CBF to blood pressure and CO2 (with more impairment of vasodilatation in response to hypercapnia or hypotension than vasoconstriction in response to hypocapnia or hypertension) 9). Xenon (Xe-133) CT can identify areas of low perfusion. Repeating the study after an acetazolamide challenge (which causes vasodilatation) evaluates the reserve capacity of CBF and can identify areas of “steal” which are at high risk of future infarction.

References

1)

Smith ER, Scott RM. Surgical management of moyamoya syndrome. Skull Base. 2005; 15:15–26
2)

Nishimoto A. Moyamoya Disease. Neurol Med Chir. 1979; 19:221–228
3)

Research Committee on the Pathology and Treatment of Spontaneous Occlusion of the Circle of Willis; Health Labour Sciences Research Grant for Research on Measures for Infractable Diseases. Guidelines for diagnosis and treatment of moyamoya disease (spontaneous occlusion of the circle of Willis). Neurol Med Chir (Tokyo). 2012;52(5):245-66. PubMed PMID: 22870528.
4)

Kazumata K, Tha KK, Uchino H, Ito M, Nakayama N, Abumiya T. Mapping altered brain connectivity and its clinical associations in adult moyamoya disease: A resting-state functional MRI study. PLoS One. 2017 Aug 4;12(8):e0182759. doi: 10.1371/journal.pone.0182759. eCollection 2017. PubMed PMID: 28783763.
5)

Gao XY, Li Q, Li JR, Zhou Q, Qu JX, Yao ZW. A perfusion territory shift attributable solely to the secondary collaterals in moyamoya patients: a potential risk factor for preoperative hemorrhagic stroke revealed by t-ASL and 3D-TOF-MRA. J Neurosurg. 2019 Aug 9:1-9. doi: 10.3171/2019.5.JNS19803. [Epub ahead of print] PubMed PMID: 31398708.
6)

Suzuki J, Takaku A. Cerebrovascular “moyamoya” disease. Disease showing abnormal net-like vessels in base of brain. Arch Neurol. 1969 Mar;20(3):288-99. PubMed PMID: 5775283.
7)

Kodama N, Aoki Y, Hiraga H, et al. Electroencephalographic Findings in Children with Moyamoya Disease. Arch Neurol. 1979; 36:16–19
8)

Ogawa A, Yoshimoto T, Suzuki J, Sakurai J. Cerebral Blood Flow in Moyamoya Disease. Part 1. Correlation with Age and Regional Distribution. Acta Neurochir. 1990; 105:30–34
9)

Ogawa A, Nakamura N, Yoshimoto T, Suzuki J. Cerebral Blood Flow in Moyamoya Disease. Part 2. Autoregulation and CO2 Response. Acta Neurochir. 1990; 105:107–111
WhatsApp WhatsApp us
%d bloggers like this: