Causes and risk factors
Causes of rubeosis iridis are diabetes mellitus, central retinal venous occlusion, carotid artery occlusive disease, intraocular tumours, anterior segment ischemia. It can be caused following vitrectomy surgery in aphakic eyes. When the retina is deprived of oxygen, new blood vessels are formed in order to maintain blood supply to the eye. The new blood vessels and associated fibrous tissue may cover the trabecular meshwork causing peripheral anterior synechiae [abnormal adhesions of the iris]. This closes the angle of anterior chamber. This hampers the drainage of aqueous fluid causing raised intraocular pressure. This leads to intractable neovascular glaucoma.
Clinical presentation
Patient with rubeosis iridis presents with symptoms like blurred vision, rings, spots, or floating objects in front of the eyes. There is pain in the eyes. There is reduced peripheral vision. If left untreated, it can lead to complete loss of vision.
Investigation
Medical history by the patient and clinical examination by the ophthalmologist helps in diagnosis. Tonometry in which the pressure within the eye [intraocular pressure] is measured. Ophthalmoscopy is advised. Visual field testing is recommended. Measurement of visual acuity is done. Gonioscopy is done to inspect the drainage angle.
Treatment
It is difficult to treat rubeosis iridis. Panretinal photocoagulation is the treatment of choice. Panretinal cryocoagulation also helps in treating the condition. Cyclocryotherapy is recommended in resistant cases. Control of blood sugar levels is required. Following a healthy diet and regular exercise for controlling diabetes will contribute to the treatment.
