2020–2021 BCSC Basic and Clinical Science Course™
12 Retina and Vitreous
Part II: Disorders of the Retina and Vitreous
Chapter 07: Other Retinal Vascular Diseases
Macular Telangiectasia Type 3
Type 3 macular telangiectasia is an extremely rare vasocclusive process that affects the parafoveal region and is distinct from type 1 and 2 macular telangiectasias.
Figure 7-11 MacTel 2 OCT and OCT angiography (OCTA) imaging. A, Volume-rendered OCTA image of a right eye with MacTel 2. At the level of the superficial vascular plexus, the vessels are blue; at the deep plexus they are red; and deep to the deep plexus, they are yellow. Retinal cavitations are real. A contraction in the temporal juxtafoveal region causes a dragging of the perifoveal capillary ring temporally. Note the dragging of vessels such as the large retinal vein (arrowheads), producing an appearance of a right-angle vein. B, OCTA image shows enlargement of the area of contracture in the temporal juxtafoveal macula. Note the angled capillary segments (green arrow) that point toward the epicenter of the contracture. C, A slab OCTA image shows the outer nuclear layer, a region that is ordinarily avascular. The slab is taken at the same level as the arrow shown in (E). Note the angled vascular segments. D, The corresponding slab structural OCT shows a hyperreflective region where the vessels are located. E, This B-scan structural OCT shows a flow overlay in red. The scan was taken at the location of the green line shown in (C) and (D). The hyperreflective material extends nearly the full thickness of the retina (arrow). The red lines in (C), (D), and (E) are all at the same location. Note the considerable flow (red color) on the temporal side. Nasal to the hyperreflective region are cavitations (arrowheads). Over time, cavitations change in size, shape, and number.
(Courtesy of Richard F. Spaide, MD.)
Clemons TE, Gillies MC, Chew EY, et al; MacTel Research Group. Baseline characteristics of participants in the natural history study of macular telangiectasia (MacTel). MacTel Project report no. 2. Ophthalmic Epidemiol. 2010;17(1):66–73.
Yannuzzi LA, Bardal AM, Freund KB, Chen KJ, Eandi CM, Blodi B. Idiopathic macular telangiectasia. Arch Ophthalmol. 2006;124(4):450–460.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.