Retinal arterial macroaneurysms are fusiform or round arteriolar dilations occurring in the posterior pole, within the first three orders of a retinal arterial bifurcation.
They are usually unilateral, associated with systemic hypertension, are more common in females and occur in the fifth to sixth decades of life.
Clinical features may be classified into two basic groups: one group denotes an acute aneurismal decompensation in which hemorrhage is the predominant clinical feature, while the other group is characterized by perianeurysmal and macular exudation.
Bleeding from a macroaneurysm can occur in the subretinal space, in the retina, beneath the internal limiting membrane, or in the vitreous.
Abdel-Khalek MN, Richardson J: Retinal macroaneurysm: natural history and guidelines for treatment. Br J Ophthalmol 70:2-11, 1986.