Abstract
Purpose :
Optic disc edema (ODE) associated with uveitis is termed uveitic disc edema (UDE). Visual field tests and retinal nerve fiber layer (RNFL) thickness are often used in diagnosing UDE, while optical coherence tomography (OCT) optic disc raster scans remain underutilized. The severity of visual field defects does not always correlate to the degree of ODE in papilledema and other optic neuropathies. We hypothesized that the severity of visual field defects in patients with UDE would not correlate with RNFL thickness and that disc raster OCT scans could help evaluate and monitor UDE.
Methods :
We performed a retrospective study of 59 eyes from 33 patients seen by a single uveitis provider at the University of Minnesota. Inclusion criteria were (1) presence of uveitis, (2) optic disc edema, and (3) visual field, optic disc raster imaging and OCT RNFL thickness measurements obtained within a 2-week interval. Visual field tests were organized into 7 categories based on patterns of defects and then each pattern identified was assigned a grade of severity (focal, diffuse, or no/minor defects). OCT disc raster images were classified using terminology used to discuss OCT of the macula.
Results :
The following visual field defects were identified: normal (8.5%), blind spot enlargement (15.3%), central/paracentral defects (3.4%), nasal/arcuate defects (47.5%), scattered/nonspecific defects (18.6%), generalized depression (25.4%), and mixed defects (20.3%). The average RNFL thickness for all eyes in the study was 155 μm. No correlation was found between the severity of visual field defects and RNFL thickness (p=0.20). Many optic disc raster scans showed diffuse (57.6%) and inner-middle (30.5%) retinal thickening, while nerve fiber layer thickening (5.1%) and no thickening (6.8%) were less common.
Conclusions :
The lack of correlation between RNFL thickness and severity of visual field defects emphasizes the need for additional diagnostic modalities in UDE. The OCT raster scan provides structural information beyond the measurement of RNFL thickness, and we intend to explore disc raster morphology and possible relationship to the specific visual field abnormalities.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.