Retinal nerve fiber layer analysis using GDx® in 49 patients with chronic phase DUSN

PURPOSE: To describe retinal nerve fiber layer changes in late-stage diffuse unilateral subacute neuroretinitis eyes and compare these results with healthy eyes observed through nerve fiber analyzer (GDx®). METHODS: This is a retrospective case-control study in which 49 eyes in late-stage diffuse unilateral subacute neuroretinitis were examined from May/97 to December/01. First, eyes with diffuse unilateral subacute neuroretinitis and healthy contralateral eyes (Control Group I) were statistically matched. Subsequently, eyes with diffuse unilateral subacute neuroretinitis were compared with eyes of healthy patients (Control Group II). RESULTS: Eyes from Control Groups I and II had higher relative frequency of "within normal limits" status. Eyes from the diffuse unilateral subacute neuroretinitis (DUSN) Group had higher frequency of "outside normal limits" and "borderline" status. Control Groups I and II had absolute values different from the DUSN Group regarding all parameters (p<0.05), except for Symmetry in Control Groups I and II, Average thickness and Superior Integral in control group II. CONCLUSION: Patients with late-stage diffuse unilateral subacute neuroretinitis presented presumed decrease in nerve fiber layer thickness shown by GDx®. Retinal zones with larger vascular support and larger amount of nerve fibers presented higher decrease in the delay of the reflected light measured by the nerve fiber analyzer.