Vascular Changes Occur Later in MacTel Disease Course

The initial clinical classification system for macular telangiectasia type 2 (MacTel) relied on biomicroscopic and fluorescein angiographic findings. OCT angiography (OCT-A) is a noninvasive modality capable of providing rapid, depth-resolved assessments of retinal and choroidal circulation. Researchers at Massachusetts Eye and Ear at Harvard Medical School recently explored retinal vascular and choriocapillaris alterations in a large cohort of MacTel eyes. This study highlights the intricate interplay between neurodegeneration and vascular alterations in MacTel, as assessed by swept-source OCT-A. MacTel eyes demonstrated increased vascularization around the foveal avascular zone, pronounced vessel rarefaction in the inner ring and temporal sector and significant impairment of the macular choriocapillaris. The above OCT image with superimposed flow signal from the study shows macular neovascularization (orange dotted line) and the choriocapillaris slab (yellow dotted lines). Due to the presence of macular neovascularization, an additional angiographic slab between the external border of the outer plexiform layer and Bruch’s membrane was captured and the neovascular complex was delineated (green line). Photo: Stettler I, et al. Invest Ophthalmol Vis Sci. 2026;67(2):44. Click image to enlarge. Their study found significant vascular changes across all layers, with pronounced alterations in the inner ring and temporal ETDRS sectors. Analysis of OCT-A vascular metrics across the seven grades defined by the MacTel Project Classification revealed substantial differences in advanced grades (5 to 6) compared to controls and grade 0 eyes, which lacked structural OCT alterations. This cross-sectional, observational study, which was published in Investigative Ophthalmology & Visual Science, included 111 eyes with MacTel (56 patients) and 120 matched control eyes (60 subjects). Of the MacTel eyes, 32% were grade 0, 9% grade 1, 18% grade 2, 5% grade 3, 15% grade 4, 13% grade 5 and 8% grade 6.MacTel eyes exhibited significant alterations in vessel density (VD) and vessel skeletonized density, particularly in the central 1mm circle and temporal/inferior sectors, alongside consistently higher choriocapillaris flow deficit percentage across all macular regions. Advanced grades (5 and 6) showed pronounced differences in VD, vessel skeletonized density and choriocapillaris flow deficit percentage, compared to early grades (0 to 2). Agreement between MacTel grading and OCT-A-based clusters was fair to moderate, with higher concordance for grades 0 and 4 to 6.“We found that advanced disease grades (4 to 6) were associated with increased foveal VD and vessel skeletonized density in the deep capillary plexus, corresponding to the presence of outer retinal hyperreflectivity on OCT, central pigment and macular neovascularization,” the researchers noted. “Conversely, significant vascular rarefaction was observed in the inner ETDRS ring and temporal sector in grades 5 to 6, with less pronounced changes in the deep capillary plexus, potentially due to concomitant vessel telangiectasias.”Interestingly, early stages of MacTel did not show significant retinal vascular differences compared to controls, suggesting that vascular changes occur later in the disease course.Advanced grades demonstrated increased vascular metrics in the central 1mm circle but decreased metrics in the outer ETDRS regions when assessing the whole retina. Notably, no differences were observed among MacTel grades when analyzing the whole retinal vasculature in the four ETDRS sectors, indicating that individual capillary plexus analysis may be more sensitive for detecting vascular changes.“These findings enhance our understanding of MacTel pathogenesis and support the clinical utility of OCT-A across various disease stages, especially given the current lack of established functional and structural endpoints,” the researchers concluded. “This study lays the groundwork for future longitudinal research to explore the prognostic value of OCT-A in predicting complications, such as subretinal neovascularization.”Click here for the journal source. Stettler I, Romano F, Ding X, et al. Optical coherence tomography angiography characterization of vascular alterations in macular telangiectasia type 2. Invest Ophthalmol Vis Sci. 2026;67(2):44. This article was developed by the editorial staff in conjunction with experts in the field. In the process, AI may have been among the editorial tools used to meet the goals of human editors, who approved all content.