[Cotton-wool spots as first ocular manifestation of giant cell arteritis]

Giant cell arteritis is the most common vasculitis in the elderly. Visual loss is established as the most dreaded and irreversible complication of the disease, which makes giant cell arteritis an ophthalmic emergency. It is important to recognize its various ocular manifestations; isolated cotton wool spots are one of them.

We describe a patient with constitutional symptoms and mild visual loss who was found to have giant cell arteritis. The ophthalmic examination was significant for only isolated cotton-wool spots. A delay in arm-to-retina circulation time was demonstrated by fluorescein angiography. Prompt treatment with corticosteroids led to preservation of vision and uneventful resolution of the cotton-wool spots.

Common ophthalmologic presentations include anterior ischemic optic neuropathy or choroidal ischemia when short posterior ciliary arteries are involved, and central retinal artery occlusion. Retinal ischemia has also been recognized as a possible manifestation. Because the disease concerns medium-size and larger arteries, it cannot involve terminal retinal arterioles to produce cotton-wool spots. These are probably caused by platelet microembolization from the partially thrombosed regional arteries.

Isolated cotton-wool spots can be an early ophthalmoscopic finding in giant cell arteritis and precede severe irreversible visual loss. Their detection is essential because it allows the ophthalmologist to establish a prompt treatment and preserve vision.