Diagnosis of hemiplegic migraine is based on a history of recurrent attacks of weakness associated with atypical headache, as in the present case. The clinical presentation of this case fulfils the diagnostic IHS criteria for sporadic hemiplegic migraine,4
a form of complicated migraine.4
In 1971, Verret and Steele described eight patients with hemiplegic migraine in childhood and one child with hemiplegic migraine at 3 months of age.5
However, all cases of sporadic hemiplegic migraine require neuroimaging and other advanced investigations to rule out other causes.4
In our case we also sought to exclude other causes of migraine. MRI of the brain of our patient showed some signal change, which was later confirmed by MRA and cerebral DSA as a very rare case of moyamoya disease presenting as hemiplegic migraine.
In Japan, moyamoya disease is also called ‘spontaneous occlusion of the circle of Willis’. In endemic areas, approximately 10% of local populations are genetically predisposed to the disease.6
Linkage was found with loci on chromosomes 3p24.2-26 and 17q25 and on chromosome 6.6
Clinical manifestation depends on age; headache, seizure, TIAs and ischaemic strokes are more common in childhood, whereas subarachnoid and intracerebral haemorrhage occur more frequently in adulthood.7
There are two peaks in the age of presentation: below 10 and between 30 and 40 years of age, with the highest peak in the first decade and a lower peak in adulthood.8
Only a few previous reports indicate that headache is a common symptoms in paediatric patients with moyamoya disease.7
In 1993, Bernstein described an association between hemiplegic migraine and moyamoya disease in a 6-year-old girl.9
Imaging such as CT and MRI is useful to differentiate between ischaemia and haemorrhagic stroke. MRA is a non-invasive investigation to detect vascular abnormality,7 10
but the gold standard for diagnosis and follow-up is cerebral DSA.7
With DSA classical angiographic changes can be seen, such as progressive stenosis leading to occlusion of the supraclinoidal ICAs (usually bilateral) also involving the proximal MCA or ACA and numerous dilated perforating vessels in the base of the brain giving rise to the typical ‘moyamoya’ (puff of smoke) appearance.7 11
Development of parenchymal, leptomeningeal or transdural collateral vessels can also be seen with additional collateral supply from branches of the external carotid artery and the ophthalmic system, all supplying the ischaemic brain.11
Early diagnosis and treatment are important during childhood as the disease can cause progressive disability, including deterioration in cognitive ability,12
because viable cerebral tissue is necessary for reperfusion. The efficacy of the medical and surgical treatment of moyamoya disease is still controversial. In adults, treatment is aimed at improving cerebral ischaemia and preventing repeated intracerebral haemorrhage by reducing the overload on moyamoya collaterals.12
In children the first line of treatment is pharmacological with anti-platelet therapy or calcium channel blockers, which can improve symptoms but do not halt disease progression.7 12 13
Direct superficial temporal artery to MCA bypass is considered the treatment of choice, although its efficacy, particularly for haemorrhagic disease remains, uncertain. Multiple burr holes have been used in frontal and parietal lobes with good neovascularisation achieved. However, the most favoured approaches currently are the indirect procedures EDAS (encephalo-duro-arterio-synangiosis) and EMS (encephalo-myo-synangiosis). It is very important to treat this condition promptly as once a major ischaemic or bleeding event takes place, even with treatment, the patient may be left with permanent loss of function.14
- All vascular headache with uncommon age and atypical presentations should be evaluated properly.
- Moyamoya disease is a rare central nervous system vascular anomaly more common in Asian populations.
- Hemiplegic migraine is a very uncommon presentation of moyamoya disease and we have found only a single previously reported case.
- Early diagnosis of the disease is important so that advanced management can be instituted.