Purpose: To investigate the clinical features of central retinal vein occlusion (CRVO) in relation to the presence of a prominent middle limiting membrane (p-MLM) sign on presenting optical coherence tomography, which may suggest macular ischemia and poor visual outcome.
Methods: Fifty consecutive eyes with acute CRVO of <1 month of symptom duration before presentation were retrospectively reviewed. A hyperreflective line located in the outer plexiform layer (p-MLM) in optical coherence tomography was used as a sign of acute ischemia. Cases with p-MLM were grouped and compared with the group of eyes with no p-MLM sign (non-MLM group) for clinical features including visual acuities, central fovea thickness, and CRVO types.
Results: Among the 50 eyes, 14 (28%) eyes showed a p-MLM sign, 21 (42%) eyes did not, and others had equivocal findings. Eyes with p-MLM sign presented worse initial and final best-corrected visual acuity compared with the non-MLM group (1.10 ± 0.72 vs. 0.47 ± 0.49 logMAR in the initial best-corrected visual acuity, P = 0.007; and 1.08 ± 0.86 vs. 0.32 ± 0.41 logMAR in the final best-corrected visual acuity, P = 0.044) in patients with a follow-up duration of 6 months or longer. The p-MLM group eyes showed a higher tendency toward being classified as ischemic type CRVO (57.1 vs. 4.8%, P = 0.001).
Conclusion: Central retinal vein occlusion showing p-MLM on optical coherence tomography had worse visual outcome with higher incidence of being classified into ischemic type CRVO.