Two adolescent patients with coexistent Graves' disease and Moyamoya disease in Korea

Research progress on moyamoya disease combined with thyroid diseases

Moyamoya disease (MMD), also known as abnormal cerebral vascular network disease, is characterized by progressive occlusion or stenosis of the internal carotid and cerebral arteries, as well as the formation of an abnormal cerebral vascular network. It can occur anywhere in the world but is most common in China, Japan, and the Republic of Korea. In recent years, there have been increasing reports on the coexistence of thyroid diseases and MMD, but the mechanism of their coexistence is still unclear. For this article, we used keywords such as "moyamoya disease", "thyroid", "Grave disease", "thyrotoxicosis", and "thyroid autoimmune antibodies" to search for 52 articles that met the requirements in medical databases such as PubMed and Web of Science. This article also reviews the research on the role of thyroid hormone, the mechanism of immune antibodies, the possible correlation between thyroid diseases and MMD disease genes, and the treatment methods, and discusses the possible relationship between MMD and thyroid diseases to provide a reference for the pathogenesis and treatment of MMD with thyroid diseases.

Moyamoya Disease Associated with Graves' Disease and Down Syndrome: A Case Report and Literature Review

BACKGROUND

Moyamoya vessels are cerebral vasculopathies characterized by net-like collateral vessel formation at the cerebral basal area and stenosis of the terminal internal carotid artery, proximal middle cerebral artery, and anterior cerebral artery. A diagnosis of Moyamoya disease depends on the bilateral presence of Moyamoya vessels. Moyamoya disease associated with Graves' disease has rarely been reported to be a cause of ischemic events due to hyperthyroidism. However, there are extremely rare cases of Moyamoya disease with concurrent Graves' disease and Down syndrome. We aimed to report such a case, and to compare these cases' clinical features, pathogenesis, and treatment effects to those of the cases of concurrent Moyamoya disease and Graves' disease alone.

METHODS

We performed an English literature search using the PubMed database and the keywords Moyamoya, quasi-Moyamoya, Graves' disease, thyrotoxicosis, Down syndrome, and trisomy 21.

RESULTS

Only five cases of Moyamoya disease with Graves' disease and Down syndrome have been reported, including our own. Four patients were female (80%), and all underwent antithyroid therapy and experienced ischemic episodes, including transient ischemic attacks. At the time of their vascular accident, two patients were in a thyrotoxic state; only our patient was in a euthyroid state. The mean age was 15.6 years (standard deviation: 6.1), which was younger than the mean age of 31.4 years (standard deviation: 13) in patients with Moyamoya disease and Graves' disease alone. Down syndrome is commonly associated with abnormal vascular networks due to increased endostatin concentrations or immunological abnormalities such as those that occur in Graves' disease. Graves' disease accelerates the progression of Moyamoya disease and ischemic attacks due to atherosclerosis, enhances sympathetic nervous system activity and immunological changes. As compared to Moyamoya disease patients, patients with concurrent Graves' disease only and Moyamoya disease patients with concurrent Graves' disease and Down syndrome may experience accelerated disease progression or more frequent ischemic attacks.

CONCLUSION

Early imaging follow-ups and strict control of thyroid function are necessary in such cases; if ischemic attacks have already occurred, revascularization surgery may be effective.

Acute Thyrotoxicosis of Graves Disease Associated with Moyamoya Vasculopathy and Stroke in Latin American Women: A Case Series and Review of the Literature

OBJECTIVE

Moyamoya disease is a cerebral vasculopathy characterized by stenosis of the terminal internal carotid artery, proximal middle cerebral artery, and anterior cerebral artery. There is an association between moyamoya vasculopathy and Graves disease, primarily in Asian populations. Here, we present the largest series of non-Asian, predominantly Latino patients with moyamoya vasculopathy in the setting of Graves thyrotoxicosis, as well as the largest review of the literature to date.

METHODS

We retrospectively analyzed patients presenting with stroke in the setting of clinical Graves disease to our institution from 2004 to 2014. Moyamoya vasculopathy was diagnosed by magnetic resonance angiography in all patients.

RESULTS

Eight patients with Graves disease thyrotoxicosis and moyamoya vasculopathy were identified. Six patients were effectively managed with aggressive medical management using antithyroid and antiplatelet medications. No recurrent strokes were noted once thyrotoxicosis was controlled. Intracranial bypass was necessary in 2 patients who failed medical management. Seventy-nine additional cases were reported from the literature. There was no significant difference in clinical improvement between medical therapy alone and medical therapy with neurosurgical prophylaxis (87.0% vs. 88.0%, respectively; P = 0.94).

CONCLUSIONS

Moyamoya vasculopathy associated with Graves disease thyrotoxicosis in non-Asian women may be more common than previously thought. In addition, our series suggests that thyrotoxicosis promotes the progression of vasculopathy. Based on our review, there is no significant difference in clinical improvement between proper medical and surgical therapies. Aggressive medical therapy should be considered first-line treatment for moyamoya vasculopathy with Graves thyrotoxicosis, with neurosurgical rescue reserved for medically refractory cases.