[Vogt-Koyanagi-Harada disease]. / La maladie de Vogt-Koyanagi-Harada.

Vogt-Koyanagi-Harada (VKH) disease is defined as a severe bilateral, chronic granulomatous panuveitis associated with serous retinal detachments, disk edema, and vitritis, with central nervous system, auditory, and integumentary manifestations. It is an autoimmune inflammatory condition mediated by T cells that target melanocytes in individuals genetically susceptible to the disease. Vogt-Koyanagi-Harada disease presents clinically in 4 different phases: prodromal, acute inflammatory, chronic, and recurrent, with extraocular manifestations including headache, meningitis, hearing loss, poliosis, and vitiligo. Optical coherence tomography (OCT) allows earlier diagnosis of VKH disease by revealing heterogeneous exudative detachments of the retina in the acute stage and choroidal thickening, and by demonstrating choroidal thinning in the chronic stage. Treatment of this disease is initially with intravenous corticosteroids, with, if needed, a transition to immunosuppressant drugs for long-term control. Patients with VKH disease can have good final visual outcomes if treated promptly and aggressively.

[Acute total cataract in a 17-year-old woman]. / Cataracte aiguë chez une jeune fille diabétique.

Diabetes is a metabolic disease that has multiple consequences on the eye, particularly the retina but also the lens. However, in diabetic patients, the development of an acute decrease in vision is rarely caused by a cataract and diabetic lens opacities usually appear progressively several years after the diagnosis of diabetes. We present here the case of a young patient who had just been diagnosed with diabetes two months before and who developed an acute total cataract, responsible for a rapid decrease in vision. Then we discuss the possible mechanisms involved in its physiopathology.

[Cotton-wool spots as first ocular manifestation of giant cell arteritis]. / Artérite à cellules géantes révélée par des nodules cotonneux.

INTRODUCTION: 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. CASE REPORT: 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. DISCUSSION: 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. CONCLUSION: 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.