[Cerebral venous sinus thrombosis presenting transient ischemic attack after recovery from COVID-19 with Graves' disease and IgG4-related ophthalmic disease: a case report].

A 57-year-old man presented with headache, transient right upper extremity weakness and numbness one month after recovery from coronavirus disease 2019 (COVID-19). His medical history included Graves' disease and IgG4-related ophthalmic disease. He had been administered prednisolone. His weakness and numbness were transient and not present on admission. Contrast-enhanced CT and MRI of the head showed thrombi in the superior sagittal sinus, right transverse sinus, sigmoid sinus, and the right internal jugular vein. Digital subtraction angiography showed occlusion at the same sites and mild perfusion delay in the left frontoparietal lobe. We diagnosed the patient with cerebral venous sinus thrombosis and treated him with anticoagulation. The thrombi partially regressed three months later, and perfusion delay became less noticeable. Cerebral venous sinus thrombosis is an important complication of COVID-19. Patients with predisposing factors, including Graves' disease and IgG4-related ophthalmic disease, may be at increased risk of developing cerebral venous sinus thrombosis even after recovery from COVID-19.