EARLY SPECTRAL-DOMAIN OPTICAL COHERENCE TOMOGRAPHY BIOMARKERS TO CONFIRM FELLOW EYE CHANGES IN ASYMMETRIC TYPE-2 MACULAR TELANGIECTASIA: A Case-Control Study (India Macular Telangiectasia Report 1).

PURPOSE

To evaluate the earliest spectral-domain optical coherence tomography markers in fellow eyes of asymmetric Type-2 macular telangiectasia (MacTel).

METHODS

A multicentered case-control study of spectral-domain optical coherence tomography images captured on Spectralis Heidelberg Engineering, Germany, comparing features of fellow eyes of patients with asymmetric clinical presentation of MacTel with 50 age-matched control subjects.

RESULTS

Of 649 patients, 28 (4.3%) with MacTel presented with asymmetric features. The mean age of the MacTel patients was 63.5 (12.4) years with female predilection (4:1). Mean best-corrected visual acuity of the unaffected eye was 0.2 logarithm of the minimum angle of resolution (20/32 Snellen equivalent). The mean central subfoveal thickness in the unaffected MacTel eyes was 194 (SD, 38) µm, and the temporal retinal thickness was 204 (SD, 43) µm. These parameters were significantly thinner than those of control subjects in whom mean central subfoveal thickness was 273 (SD, 26) µm (P = 0.001). Presence of hyperreflective outer retinal dots was found in 92.8% of the unaffected MacTel eyes. These hyperreflective dots were scattered, punctate, nonconfluent, and confined to the outer retinal layers of foveal and parafoveal region.

CONCLUSION

Although these cases presented with advanced presentation of MacTel features in only one eye, temporal retinal thinning and presence of hyperreflective outer retinal dots in the fellow eye can be considered as the earliest signs of MacTel.