Macular sub-ILM hemorrhage as a favorable prognostic factor in ruptured retinal arterial macroaneurysm

To examine the relationship between macular sub-internal limiting membrane (sub-ILM) hemorrhage, foveal subretinal hemorrhage (SRH), and final visual acuity in ruptured retinal arterial macroaneurysm (RAM).

This retrospective study included 32 consecutive eyes with ruptured RAM. SRH beneath the ruptured RAM caused visual loss requiring treatment. Patients underwent pars plana vitrectomy (PPV) with sulfur hexafluoride (SF₆), PPV alone, or SF₆ alone. Foveal SRH and macular sub-ILM hemorrhage were recorded. Multiple linear regression evaluated associations of foveal SRH and macular sub-ILM hemorrhage with final logMAR visual acuity.

Mean age was 79.0 ± 7.4 years. Mean logMAR acuity improved from 1.64 ± 0.46 to 0.79 ± 0.55 (P < 0.001). Foveal SRH was present in 18 eyes and macular sub-ILM hemorrhage in 15. Macular sub-ILM hemorrhage was inversely associated with foveal SRH (P = 0.031; odds ratio, 0.15). Final logMAR acuity was worse with foveal SRH (1.12 ± 0.45 vs. 0.37 ± 0.36; P < 0.001) but better with macular sub-ILM hemorrhage (0.45 ± 0.42 vs. 1.09 ± 0.48; P = 0.002). Regression showed foveal SRH predicted worse acuity (β = +0.57, 95% CI [+ 0.27, + 0.88], P < 0.001), whereas macular sub-ILM hemorrhage predicted better acuity (β = -0.39, 95% CI [- 0.70, - 0.09], P = 0.013; R² = 0.567).

In ruptured RAM, macular sub-ILM hemorrhage was inversely associated with foveal SRH and remained a favorable prognostic factor. A mechanical interaction between retinal layers, in which macular sub-ILM hemorrhage displaces subretinal blood away from the fovea, may have contributed to the better visual outcome.