Idiopathic Macular Telangiectasia

OBJECTIVES: To review the frequency and nature of idiopathic macular telangiectasia and to classify the disorders based on new clinical and imaging observations. METHODS: A combined retrospective and prospective analysis of newly diagnosed patients seen over a period of 3 years. Patients were identified based on the Gass-Blodi classification and were studied with biomicroscopy, fluorescein angiography, and optical coherence tomography. RESULTS: Ten patients associated with aneurysmal telangiectasia (Gass-Blodi group 1) and 26 patients with perifoveal telangiectasia (Gass-Blodi group 2) were recruited. None with occlusive telangiectasia (Gass-Blodi group 3) were identified. New observations based on clinical, fluorescein angiographic, and optical coherence tomographic findings were made. CONCLUSIONS: Our series was similar to that in the Gass-Blodi study in terms of frequency. New observations in groups 1 and 2 have expanded our knowledge of the clinical spectrum of these disorders. A simplified classification termed idiopathic macular telangiectasia with 2 distinct types (type I, or aneurysmal telangiectasia, and type II, or perifoveal telangiectasia) was proposed to produce a better understanding of the entities and to enhance teaching and research. The third type, occlusive telangiectasia, has been omitted from our classification based on its rarity and presence of capillary nonperfusion rather than macular telangiectasia as the primary abnormality.