STRUCTURAL AND FUNCTIONAL CHANGES OVER TIME IN MacTel PATIENTS

Abstract

In Brief Purpose: To investigate functional and morphologic alterations over a 1-year review analysis in patients with type 2 idiopathic juxtafoveal retinal telangiectasia (MacTel). Methods: Nine eyes of 9 patients with MacTel underwent repeated scotopic and photopic fine matrix mapping (FMM), 10-2 photopic microperimetry, and imaging studies. Results: Early Treatment Diabetic Retinopathy Study visual acuity assessment showed a median difference between examinations of 1.0 letter (range, −3 to 4 letters). The difference of sensitivity values of all test points was 4.5 dB (range, 0.4–5.5 dB) for microperimetry 1, 0.4 dB (range, −0.8 to 1.7 dB) for photopic, and −1.7 dB (range, −6.1 to 1.0 dB) for scotopic fine matrix mapping, respectively. The difference in test points of more than a 10-dB loss compared with age-matched controls was higher for scotopic than for photopic testing (P = 0.03, Wilcoxon signed ranks test). Small progression of scotoma correlated with a slight increase in retinal blood vessel dilatation and hyperfluorescence and subtle enlargement of pigmented plaques. Conclusion: Changes in central visual acuity and microperimetry testing after 1 year most likely do not extend beyond test–retest variability. The deterioration of scotopic sensitivity confirms our previous results of more severe rod compared with cone dysfunction in MacTel. Changes in fine detail visual function over a 1-year period may be useful parameters for interventional trials. Fine-detailed visual function testing may demonstrate progression of localized retinal dysfunction in patients with Type 2 idiopathic juxtafoveal retinal telangiectasia already within 1 year that correlates with slight morphological changes and that is not detectable with central visual acuity testing.