Abstract
Purpose :
To evaluate the morphologic changes in the optic nerve head (ONH) in eyes with central retinal vein occlusion (CRVO) that have received treatment with ≥ 20 intravitreal injections (IVI).
Methods :
The electronic medical records and OCT images of patients with CRVO were retrospectively reviewed. The following inclusion criteria were used: (a) documented history of having received ≥ 20 IVI; (b) available optical coherence tomography images that allowed adequate visualization of the temporal Bruch membrane opening (BMO), anterior lamina cribrosa (ALC), and prelaminar tissue (PLT) at the nadir of the optic cup within 2 horizontal line scans of the midpoint of the optic disc. The following were measured and compared between the affected eye and the fellow eye (if available) from the initial examination to last follow-up: Bruch membrane to anterior lamina cribrosa distance (BM-ALC) and prelaminar tissue thickness (PLTT).
Results :
Eight patients met inclusion criteria. A PLTT decrease > 10 um occurred in 7/8 CRVO eyes (average decrease = 44.3 um). No fellow eyes had an increase or decrease in PLTT > 10 um. BM-ALC increase > 10 um occurred in 3/8 CRVO eyes compared to 1/7 fellow eyes. In CRVO eyes, the following average values were calculated: initial BM-ALC (323.0 um), final BM-ALC (331.9 um), initial PLTT (210.9 um), and final PLTT (172.5 um). In fellow eyes without CRVO, the following average values were calculated: initial BM-ALC (340.7 um), final BM-ALC (336.4 um), initial PLTT (177.9 um), and final PLTT (172.5 um).
Conclusions :
A substantial number (87.5%) of CRVO eyes treated with ≥ 20 IVI developed a decreased PLTT, whereas this did not occur in fellow eyes without CRVO. This may be a consequence of a morphologic vulnerability of the ONH in CRVO, the condition itself (e.g. ischemia or axonal loss), or numerous IVIs (which may contribute to transient changes in intraocular pressure or affect optic nerve head morphology independent of intraocular pressure). Further studies may elucidate the mechanism behind the changes in PLTT.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.