Spectral domain OCT features in type 2 macular telangiectasia (type 2 MacTel): its relevance with clinical staging and visual acuity

Abstract

Background To report spectral domain optical coherence tomography (SDOCT) imaging findings in type 2 macular telangiectasia (MacTel) and correlate them with clinical stages and visual acuity. Methods This retrospective, cross-sectional study included type 2 MacTel cases who underwent SDOCT imaging with Spectralis machine. Macular SDOCT images were analysed. Imaging features were tested for correlation with different clinicals stages and visual acuity. Results 212 eyes of 108 type 2 MacTel patients were included. Hyperreflective middle retinal layer (87%) was the most frequently detected abnormality. This was followed by inner retinal cavities (49%), outward bending of inner retinal layers (35%), retinal pigment clumps (35%) and foveal contour irregularity (31%). Hyperreflective middle retinal layers (p < 0.001), inner (p = 0.032) and outer retinal (p = 0.002) cavities and internal limiting membrane drape (p = 0.031) were associated with poor vision in non-proliferative group and presence of retinal pigment clumps (p = 0.002), subretinal fluid (p = 0.037) and foveal contour irregularity (p < 0.001) were associated with poor vision in proliferative group. Conclusion The described SDOCT features are practical for the diagnosis and staging in type 2 MacTel. Presence of hyperreflective middle retinal layers, hyporeflective inner and outer retinal cavities and internal limiting membrane drape were associated with poor vision in the non-proliferative group while retinal pigment clumps and subretinal neovascular membrane were associated with proliferative group and poor vision. Further long-term studies are required to describe the progressive and sequential changes on SDOCT.

Macular Telangiectasia Type 2

“… 13 , 15 It is reassuring that our findings agree with other groups, reinforcing the relevance of these imaging modalities to disease grade and risk of progression to vision loss. 30 …”

Early Optical Coherence Tomography Biomarkers for Selected Retinal Diseases—A Review

“…Loss of Müller cells in the perifoveal region may contribute to increased hyperreflectivity of MRL [70][71][72]. In type 2 MacTel, hyperreflective MRL in the perfoveal region was recognized as the most frequent early OCT finding [71].…”

Is type 2 macular telangiectasia a bilateral and symmetrical disease entity?

“…OCT scans having a quality score ≥20 were used for analysis and interpreting of the findings. The presence of the following features of type 2 MacTel was looked for as described in the previous publication from the same group: 15 (1) irregularity of the foveal contour, (2) internal limiting membrane drape sign, (3) hyperreflectivity of the middle retinal layers, i.e., between the inner plexiform to the outer plexiform layers, (4) identification of retinal crystals as superficial hyperreflective retinal dots, (5) hyporeflective inner and outer retinal cavities, (6) outward bending of inner retinal layers, (7) hyperreflective retinal pigment clumps (RPC) with underlying shadowing, and (8) SRNVM.…”