Quantitative analysis of retinal layers' optical intensities on 3D optical coherence tomography for central retinal artery occlusion

Abstract

Optical coherence tomography (OCT) provides not only morphological information but also information about layer-specific optical intensities, which may represent the underlying tissue properties. The purpose of this study is to quantitatively investigate the optical intensity of each retinal layers in central retinal artery occlusion (CRAO). Twenty-nine CRAO cases at acute phase and 33 normal controls were included. Macula-centered 3D OCT images were segmented with a fully-automated Iowa Reference Algorithm into 10 layers. Layer-specific mean intensities were determined and compared between the patient and control groups using multiple regression analysis while adjusting for age and optical intensity of the entire region. The optical intensities were higher in CRAO than in controls in layers spanning from the retinal ganglion cell layer to outer plexiform layer (standardized beta = 0.657 to 0.777, all p < 0.001), possibly due to ischemia. Optical intensities were lower at the photoreceptor, retinal pigment epithelium (RPE), and choroid layers (standardized beta = −0.412 to −0.611, all p < 0.01), possibly due to shadowing effects. Among the intraretinal layers, the inner nuclear layer was identified as the best indicator of CRAO. Our study provides in vivo information of the optical intensity changes in each retinal layer in CRAO patients.

Retinal layer reflectivity and thickness as OCT biomarkers for diagnosis and imaging-based stratification relative to the 4.5-h window in acute central retinal artery occlusion

“…We found that the within-eye IRL/ORL reflectivity ratio discriminated CRAO eyes from fellow eyes across all macular scan locations (AUC 0.98–0.99). This is consistent with prior work showing that IRL hyperreflectivity appears early after CRAO onset and reliably distinguishes CRAO from important differentials in acute vision loss ( 24 , 26 ). Similarly, retinal thickness metrics showed strong diagnostic performance, with significant thickening across most ETDRS sectors and particularly high discrimination in inferior macular regions.…”

Retinal layer reflectivity and thickness as OCT biomarkers for diagnosis and imaging-based stratification relative to the 4.5-h window in acute central retinal artery occlusion

“…We found that the within-eye IRL/ORL reflectivity ratio discriminated CRAO eyes from fellow eyes across all macular scan locations (AUC 0.98–0.99). This is consistent with prior work showing that IRL hyperreflectivity appears early after CRAO onset and reliably distinguishes CRAO from important differentials in acute vision loss ( 24 , 26 ). Similarly, retinal thickness metrics showed strong diagnostic performance, with significant thickening across most ETDRS sectors and particularly high discrimination in inferior macular regions.…”

Optical coherence tomography angiography findings in patients with acute nonarteritic central retinal artery occlusion treated with carbogen inhalation

“…This may explain the increase in the choriocapillaris flow area at 1 to 2 weeks and 4 to 6 weeks of follow-up, as the retinal edema gradually subsided. This signal attenuation secondary to high inner retinal reflectivity was consistent with the findings of Baumal [ 14 ] and Chen et al [ 15 ] Similar findings were also observed for branch retinal artery occlusion. [ 16 ]…”

Relationship between Optical Intensity on Optical Coherence Tomography and Retinal Ischemia in Branch Retinal Vein Occlusion

“…Change in optical intensity was not only seen in BRVO, but also in other retinal ischemic diseases. Our previous studies found similar results in central retinal artery occlusion 26 , 27 . The exact mechanism of optical intensity change in retinal ischemia remains unknown.…”

Retinal layer reflectivity and thickness as OCT biomarkers for diagnosis and imaging-based stratification relative to the 4.5-h window in acute central retinal artery occlusion

“…We found that the within-eye IRL/ORL reflectivity ratio discriminated CRAO eyes from fellow eyes across all macular scan locations (AUC 0.98–0.99). This is consistent with prior work showing that IRL hyperreflectivity appears early after CRAO onset and reliably distinguishes CRAO from important differentials in acute vision loss ( 24 , 26 ). Similarly, retinal thickness metrics showed strong diagnostic performance, with significant thickening across most ETDRS sectors and particularly high discrimination in inferior macular regions.…”

Optical coherence tomography angiography findings in patients with acute nonarteritic central retinal artery occlusion treated with carbogen inhalation

“…This may explain the increase in the choriocapillaris flow area at 1 to 2 weeks and 4 to 6 weeks of follow-up, as the retinal edema gradually subsided. This signal attenuation secondary to high inner retinal reflectivity was consistent with the findings of Baumal [ 14 ] and Chen et al [ 15 ] Similar findings were also observed for branch retinal artery occlusion. [ 16 ]…”

Relationship between Optical Intensity on Optical Coherence Tomography and Retinal Ischemia in Branch Retinal Vein Occlusion

“…Change in optical intensity was not only seen in BRVO, but also in other retinal ischemic diseases. Our previous studies found similar results in central retinal artery occlusion 26 , 27 . The exact mechanism of optical intensity change in retinal ischemia remains unknown.…”

Retinal layer reflectivity and thickness as OCT biomarkers for diagnosis and imaging-based stratification relative to the 4.5-h window in acute central retinal artery occlusion

“…We found that the within-eye IRL/ORL reflectivity ratio discriminated CRAO eyes from fellow eyes across all macular scan locations (AUC 0.98–0.99). This is consistent with prior work showing that IRL hyperreflectivity appears early after CRAO onset and reliably distinguishes CRAO from important differentials in acute vision loss ( 24 , 26 ). Similarly, retinal thickness metrics showed strong diagnostic performance, with significant thickening across most ETDRS sectors and particularly high discrimination in inferior macular regions.…”

Optical coherence tomography angiography findings in patients with acute nonarteritic central retinal artery occlusion treated with carbogen inhalation

“…This may explain the increase in the choriocapillaris flow area at 1 to 2 weeks and 4 to 6 weeks of follow-up, as the retinal edema gradually subsided. This signal attenuation secondary to high inner retinal reflectivity was consistent with the findings of Baumal [ 14 ] and Chen et al [ 15 ] Similar findings were also observed for branch retinal artery occlusion. [ 16 ]…”

Relationship between Optical Intensity on Optical Coherence Tomography and Retinal Ischemia in Branch Retinal Vein Occlusion

“…Change in optical intensity was not only seen in BRVO, but also in other retinal ischemic diseases. Our previous studies found similar results in central retinal artery occlusion 26 , 27 . The exact mechanism of optical intensity change in retinal ischemia remains unknown.…”