Retinal structural alterations and macular sensitivity in idiopathic macular telangiectasia type 1.

Purpose: To evaluate the relationship between the abnormalities of retinal structures showed on spectral-domain optical coherence tomography and the changes in the macular sensitivity measured by microperimetry in eyes with idiopathic macular telangiectasia type 1.

Methods: Eleven eyes of 11 patients with macular telangiectasia type 1 were reviewed. Morphologic changes in the retina and retinal sensitivity of eyes with macular telangiectasia type 1 were studied using spectral-domain optical coherence tomography and microperimetry.

Results: Spectral-domain optical coherence tomographic images revealed disruptions in the photoreceptor inner segment-outer segment (IS/OS) junction in all the eyes and intraretinal cystoid spaces in 10 eyes. In the points that had intraretinal cystoid spaces, the mean retinal sensitivity was 6.8 ± 5.5 dB where the IS/OS was disrupted and 13.4 ± 4.0 dB where the IS/OS was intact (P < 0.001). In the points that had intact IS/OS and no cystoid spaces, the mean retinal sensitivity was 15.3 ± 4.3 dB, which was better than that of points that had intact IS/OS with cystoid spaces (P < 0.001).

Conclusion: Retinal sensitivity is influenced not only by intraretinal cystoid spaces but also by IS/OS disruptions, and the IS/OS alterations reduce the visual function more severely.