July 16, 2012 1. Occlusion of central retinal artery
2. Occlusion of the branch of central retinal artery
The most common cause of retinal artery occlusion is atherosclerosis, or more precisely – embolization with the material from the carotid artery atheroma. Ophthalmoscopicly, the retina is milky white and edematous (whole or part, depending on whether the central artery or branch is affected), and the macular area on the white background stands out as bright red spot (“stain of a cherry color “). Arteries are empty, narrow, like a white thread. The symptom is sudden loss or severe reduction of vision. Differentiation of retinal vein occlusion can be set only by ophthalmologic examination.
Treatment:
Occlusion of central retinal artery is an ophthalmologic emergency and treatment should begin immediately – irreparable damage to the retina develops after only an hour of ischemia. The treatment is increasing the flow and dissemination of lumen of the affected retinal artery in order to move the embolus into more distal, smaller branch. The patient is placed in the Trendelenburg position, giving him the breathing mixture of 95% oxygen with 5% carbon dioxide (or to breathe through a paper bag), the eye is massaged, he is given a carbonic anhydrase inhibitor (500 mg acetazolamide) and the anterior chamber paracentesis is done. In some ophthalmic centers, in the first few hours after occlusion, angiography is done to locate the ophthalmic artery and given a fibrinolytic. Giving a platelet aggregation inhibitor (aspirin) reduces the likelihood of recurrent episodes of vascular occlusion.