FIG. 3.

Unilateral electroretinogram tracings of patients with groups I - III Stargardt Disease and a normal control. Normal amplitudes and implicit times are seen in both rod and cone photoreceptor systems in ERG Group I. Patients with group II disease have a reduction in the photopic waveforms and a significant implicit time delay but normal scotopic responses. Subnormal amplitudes in both photopic and scotopic responses and delay in implicit times are seen in group III disease. Note the difference in scaling required for visualization of the waveforms for Group III vs. I or II. While these waveforms were not “extinguished” they were markedly reduced. (A similar figure has been previously published in Experimental Eye Research, 2010;91(5): p.592-600. Burke T. et al., Loss of peripapillary sparing in non-Group I Stargardt Disease, Copyright Elsevier). 152×173mm (300 × 300 DPI)