Bilateral optic disc edema with preserved visual function not related to papilledema

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.

Incipient Non-Arteritic Anterior Ischemic Optic Neuropathy in a Patient with Metastatic Small-Cell Lung Cancer

A 70-year-old woman with metastatic small-cell lung cancer was referred for isolated left optic disc edema that was incidentally discovered. She had normal visual function, and dilated fundus examination revealed a small, cupless optic nerve in the right eye and moderate optic disc edema in the left eye. Magnetic resonance imaging (MRI) of the orbits with contrast was normal, and MRI brain and magnetic resonance venography were normal without signs of raised intracranial pressure. Lumbar puncture showed a normal opening pressure and normal cerebrospinal fluid contents. A diagnosis of incipient non-arteritic anterior ischemic optic neuropathy (NAION) was made, and the optic disc edema resolved after 4 months. Incipient NAION is an uncommon cause of unilateral optic disc edema with preserved visual function and is a diagnosis of exclusion. In diagnosing incipient NAION, other causes of optic disc edema must first be ruled out. These alternative causes include papilledema, optic nerve sheath meningioma or other orbital masses, and vitreopapillary traction. Incipient NAION is thought to be caused by subclinical ischemia. This case indicates that incipient NAION may also occur in patients with metastatic cancer and is possibly related to their hypercoagulable state. Although there is no treatment once vision loss develops, the optimization of risk factors may prevent the progression of incipient NAION to classic NAION.