甲状腺機能亢進症による硬膜静脈洞血栓症：症例報告

Cerebral dural venous sinus thrombosis is an uncommon and potentially life-threatening cerebrovascular disorder with a broad and often nonspecific clinical spectrum, frequently leading to diagnostic delay. We describe a young woman with no prior comorbidities who presented with a subacute history of progressively worsening headache associated with visual disturbances and pulsatile tinnitus. Neuroimaging with computed tomography and magnetic resonance venography demonstrated acute thrombosis of the right transverse dural venous sinus without parenchymal infarction or hemorrhage. Comprehensive laboratory evaluation revealed overt thyrotoxicosis with positive thyroid autoantibodies consistent with Graves' disease, while an extensive thrombophilia work-up failed to identify alternative prothrombotic risk factors. The patient was treated with therapeutic anticoagulation alongside prompt initiation of antithyroid therapy and beta-adrenergic blockade, leading to progressive symptom resolution, biochemical improvement toward euthyroidism, and radiological evidence of sinus recanalization on follow-up. This case emphasizes hyperthyroidism as an underrecognized yet reversible cause of cerebral venous sinus thrombosis and highlights the importance of systematic etiological evaluation, including thyroid function assessment, in patients with cerebral venous thrombosis to enable early targeted therapy and favorable neurological outcomes.