Abstract
Purpose: :
1. propose a systematization of the analysis of fundus alterations in late phase VKH disease; 2. describe the characteristics of overall retinal function as measured by the ffERG; 3. correlate the intensity of the fundus changes with ffERG alterations and stratify patients accordingly; 4. verify the existence of fundus markers of severe retinal dysfunction.
Methods: :
Prospective, observational and transversal study including 47 eyes of 25 patients in the late phase of VKH disease from HCFMUSP. Fundus pictures were taken (TRC 50-X, and Imaginet, 50X, Imaginet Systems, TOPCON Inc, Tokyo, Japan) within 2 months of the ffERG exam (RETI-port system-Electrophysiological Diagnostic Systems- Brandenburg, Germany), both according to pre-defined protocols. The fundus pictures were evaluated by two different observers regarding fundus pigmentation, subretinal fibrosis (SRF) and peripapillary atrophy/disc area ratio (PPA/DA). The ffERG results were compared to a normative database. The most reproducible fundus findings were correlated with ffERG groups.
Results: :
Overall fundus grading findings showed inter-observer concordance with kappa=0.78 (CI95%=0.13-0.82); peripapillary SRF was the closest to 1.0 and sunset-glow fundus was the furthest. Stratification of ffERGs into 3 groups showed that amplitudes for a and b waves in either scotopic and photopic phases, oscillatory potentials and 30Hz flicker were significantly different among the 3 groups (ANOVA, p<0.05). Stratification accordingly to ffERG measurements and fundus grading showed concordance with kappa=0.79 (0.52-1.07). The fundus findings with greater correlation with severe retinal disfunction were presence of peripapillary SRF (SMR(standardized mortality ratio)=2.94, CI95%;1.56-5.02), SRF elsewhere (2.94; 1.27-5.79), pigment clumps > 3 quadrants (2.45; 1.37-4.04).
Conclusions: :
Schematic fundus analysis coupled with the ffERG measurements help stratify late phase VKH disease patients. Systematic fundus analysis of VKH disease patients points out findings that seem more reproducible, better reflect overall retinal function and may prove useful in their prospective evaluation.
Keywords: uveitis-clinical/animal model • electroretinography: clinical