Bilateral Optic Disc Swelling with Preserved Visual Function Associated with Giant Cell Arteritis

A 68-year-old Japanese man was introduced to our hospital for optic disc swelling (ODS) in his both eyes (OU). Other than floaters in his right eye, he did not report any symptoms including blurred vision, visual field defect, and ocular pain. Light reflex was prompt and complete OU, and critical flicker frequency was within the normal range OU. By fluorescein angiography, hyperfluorescence was detected on optic discs OU; however, no fluorescein leakage or filling defect was observed. By Goldmann perimetry, enlargement of the Mariotte blind spot was revealed OU, while no central scotoma or remarkable visual field defects were detected. By neuroimaging and lumbar puncture, papilledema due to intracranial pressure elevation was denied. Based on the reassessment of fundus findings, narrowing and segmental whitening/sheathing of peripapillary vessels predominantly to arterioles were realized, and systemic arteritis was suspected. Based on the subject age, elevation of erythrocyte sedimentation rate, positron emission tomography findings in the aorta, and MRI findings in temporal arteries, underlying giant cell arteritis (GCA) was diagnosed. After the start of systemic and local steroid therapies, ODS improved OU. Although rare, bilateral ODS with no visual disturbance can occur in patients with GCA. This case emphasizes the importance of careful assessment of ocular findings to reach the correct diagnosis of even a rare cause of ODS.