Objective To investigate the distribution and clinical manifestations of intracranial arterial occlusive lesions （IAOLs）

and their correlation with thyroid function.Methods We enrolled 7 patients who had Graves’ disease （GD） with IAOLs screened and evidenced by transcranial Doppler

then further confirmed with digital substract angiography in 2 patients and magnetic resonance angiography in 5 patients. Brain magnetic resonance imaging （MRI） was performed in all 7 patients. Three patients were followed up. Results Among 7 patients

1 was male and 6 were females. The mean age was 32.0±5.5 （range from 11 to 49） years old. Six of them had symptoms of GD but one was asymptomatic with abnormality of T3

T4

and thyroid stimulating hormone. The lesions of intracranial arteries were symmetrical bilaterally in the internal carotid artery system in 6 patients

as well as asymmetrical in 1 patient. Terminal internal carotid artery （TICA） were involved in all 7 patients. Middle cerebral artery （MCA） were involved in 3

anterior cerebral artery in 2

and basilar artery in 1 patient. Net-like collateral vessels and mimic moyamoya disease were observed in the vicinity of the occlusive arteries in 2 patients. All patients presented symptoms of ischemic stroke including transient ischemic attack and/or infarction while IAOLs were found. Three patients had obvious involuntary movements. Brain MRI revealed infarctions located in the cortex

basal ganglion

or hemiovular center in 5 patients. The remaining 2 patients had normal brain MRI. The neurological symptoms were improved concomitant with relief of the thyroid function in 2 patients

while IAOLs were aggravated with deterioration of the thyroid function in 1 patient.Conclusion IAOLs in patients with GD mainly involve intracranial arteries

especially the TICA and MCA

which is similar to moyamoya disease. The neurological symptoms and severity of involved arteries may relieve while the hyperthyroidism is gradually under control.