Purpose
To determine whether disorganization of retinal inner layers (DRIL)
on optical coherence tomography (OCT) is associated with ischemia on
ultra-widefield fluorescein angiography (UWFFA) and with visual outcomes in
eyes with acute, treatment-naïve central retinal vein occlusion
(CRVO).
Design
Retrospective, single-institution, longitudinal cohort study.
Participants
Twenty-five consecutive patients with treatment-naïve CRVO
and ≥ 1 year follow-up.
Methods
Two independent masked graders evaluated the extent of DRIL,
ellipsoid zone disruption, external limiting membrane disruption, and other
OCT parameters at the baseline, 6- month, 12-month, and final visits.
Baseline UWFFA images were assessed for ischemic index values and foveal
avascular zone (FAZ) enlargement.
Main Outcome Measures
Associations of DRIL with UWFFA findings and clinical outcomes
including corrected visual acuity (VA).
Results
The median time to final follow-up was 24 months (range 12.1
– 43.9 months). Median DRIL extent at baseline was 765 µm
(range 0 – 1000 µm). Eighteen of 25 eyes (72%) had
some degree of DRIL at baseline, and 20 of 25 eyes (80%) had cystoid
macular edema (CME). Neither the presence nor extent of DRIL at baseline was
associated with presenting VA. In a cross-sectional analysis of each visit,
extent of DRIL correlated with worse VA at both the 6-month
(ρ = 0.656; p = 0.001) and final
(ρ = 0.509; p = 0.016) visits. At final
follow-up, DRIL extent was the OCT parameter most strongly correlated with
baseline ischemic index (ρ = 0.418; p = 0.047) and
baseline enlarged FAZ (p = 0.057) on UWFFA. On multivariate regression
analysis, DRIL extent at final follow-up was the only OCT parameter
associated with worse VA (p = 0.013) and remained significant when
accounting for CME as a potential confounder.
Conclusions
Extent of DRIL was not associated with presenting VA in
treatment-naïve eyes with acute CRVO. Following six months of
follow-up however, DRIL extent correlated with worse VA and was predictive
of worse VA throughout more than 2 years of follow-up. Ischemic features on
UWFFA at baseline are predictive of the extent of DRIL development at final
follow-up.