Baseline Photoreceptor and Vascular Abnormalities on OCT Angiography Predict Disease Progression in Early Macular Telangiectasia Type 2.

Abstract

Purpose: Identify imaging features on OCT angiography that predict disease progression in patients with early macular telangiectasia type 2 (MacTel).

Design: Retrospective study.

Subjects: Patients with early MacTel at baseline (grades 0-2, MacTel Project Report Number 10 grading system), defined as absence of outer retinal hyperreflectivity (grade 4), pigment migration (grade 3 and 5), or exudative neovascularization (grade 6).

Methods: We processed images using an interactive ImageJ macro. Using both en face and B-scan OCT angiography images as references, we measured the area of telangiectasia in the intermediate and deep capillary plexus, ellipsoid zone (EZ) break, interdigitation zone (IZ) break, and photoreceptor signal attenuation, defined as hyporeflective and less distinct EZ or IZ bands. We used baseline measurements of these abnormalities and their growth rate in the first year to predict EZ break growth rate as well as disease progression, defined as advancing to any higher MacTel grade during follow-up. We used logistic and linear regression analyses to identify the most important predictor variables.

Main outcome measures: Baseline predictors of MacTel progression and rate of EZ break growth.

Results: We included 39 eyes of 26 patients with early MacTel at baseline with an average of 3.7 ± 1.8 years follow-up. Twenty-one eyes (54%) had progression of MacTel grade during follow-up. For baseline predictors, larger IZ and EZ break areas as well as any telangiectasia in the superficial capillary plexus were significantly associated with MacTel disease progression at follow-up (all P < 0.05). First year growth rates of telangiectasia, EZ break, and IZ break were also significantly greater in eyes with MacTel progression (all P < 0.05), with EZ break growth rate in the first year being the most significant parameter for predicting disease progression. Photoreceptor signal attenuation area at baseline was the most significant variable for predicting future EZ break growth rate (P < 0.001).

Conclusions: In early MacTel, IZ break and photoreceptor signal attenuation areas at baseline as well as EZ break growth rate in the first year may identify eyes at risk of developing more severe MacTel 2 disease in an average of >3-year follow-up.

Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.