Inner Retinal Layer Hyperreflectivity Is an Early Biomarker for Acute Central Retinal Artery Occlusion

Abstract

PurposeTo investigate inner retinal hyperreflectivity on optical coherence tomography (OCT) as a potential biomarker indicating acute central retinal artery occlusion (CRAO).MethodsA total of 56 patients at two university hospitals with acute CRAO (symptom onset ≤48 h) were included in this retrospective study. The optical intensity of the inner retinal layers was determined in both eyes and the relationship between symptom onset and inner retinal layer optical intensity in OCT scans compared to the unaffected fellow eye was analyzed. Several differential diagnoses [central retinal vein occlusion, anterior ischemic optic neuropathy, diabetic macular edema, and subretinal fibrosis/disciform scar (Junius-Kuhnt)] served as controls to validate optical intensity-based diagnosis of CRAO.ResultsCRAO strongly correlated with an increased inner retinal layer hyperreflectivity in this cohort with acute CRAO with a time since symptom onset ranging from 1.1 to 48.0 h. Receiver operating characteristic (ROC) analysis showed an area under the curve of 0.99 to confirm CRAO with a true positive rate of 0.93 and a false positive rate of 0.02. No correlation between optical intensity and time since symptom onset was noticeable. None of the differential diagnoses did show an elevated optical intensity of the inner retinal layers as it was detectable in CRAO.ConclusionOCT-based determination of inner retinal layer hyperreflectivity is a very promising biomarker for a prompt diagnosis of CRAO in an emergency setting. This may be of major interest to speed up the administration of a possible thrombolytic treatment.

Retinal OCT findings in acute central retinal artery occlusion of varying severity at different disease stages – a retrospective, observational study

“…As a result, with a milder grade of CRAO, the opacification is limited to the middle retinal layers, with no significant retinal thickening or loss of retinal layer stratification. While the severity of the occlusion increases, the superficial capillary plexus becomes involved as well, resulting in opacification of the inner retinal layers, retinal thickening, and the absence of inner retinal layer opacification [ 16 ]. Cell body death occurs over time, resulting in retinal layer thinning and preservation of retinal layer stratification.…”

“…Cell body death occurs over time, resulting in retinal layer thinning and preservation of retinal layer stratification. The retinal opacification fades out depending on the severity of the occlusion, with the opacification in the middle retinal layers being the last to resolve [ 16 ]. Furashova et al classified acute CRAO into incomplete, subtotal, and total varieties based on the presence of inner retinal opacification with/without inner retinal layer thickening or absence of inner retinal layer stratification [ 5 ].…”

Ibudilast Protects Retinal Bipolar Cells from Excitotoxic Retinal Damage and Activates the mTOR Pathway

“…Moreover, we previously identified a hyperreflective band in the inner nuclear layer occurring 10 days after NMDA damage (T. Heisler-Taylor et al, 2021). Areas of inner retinal hyperreflectivity on OCT have been noted clinically in humans with acute retinal ischemia and are thought to represent edema of cells and nerve fibers; activated microglia are also hypothesized to compose this band (Feucht et al, 2018; Wenzel et al, 2022). Interestingly, this hyperreflectivity was less prevalent in the ibudilast-treated eyes (Fig 4A-C).…”

Evaluation of optical coherence tomography biomarkers to differentiate favourable and unfavourable responders to intravitreal anti-vascular endothelial growth factor treatment in retinopathy of prematurity

“…[26] OCT biomarkers have been used extensively to characterize adult ischaemic retinal vascular diseases like retinal vein occlusions and diabetic retinopathy. [28][29][30] Since ROP is an accelerated retinal ischaemic vascular disease, we attempted to use and analyse SS-OCT biomarkers in similar lines of ischemic vascular diseases. We did not look at these OCT biomarkers from the developmental or foveal maturation point of view.…”

“…We believe this nding could re ect more ischemic load in A-ROP eyes similar to the association of this nding in adult eyes with conditions such as ischemic central retinal vein occlusion, impending central retinal artery occlusion or ischaemic diabetic macular oedema. [28][29][30] Hyperre ectivity of inner retinal layers is mainly due to intracellular oedema and cell disorganization in acute ischaemia, resulting in loss of transparency in OCT images. [28][29][30] Another important OCT biomarker seen in ischemic conditions is choroidal thinning and this has been reported previously in association with increasing ROP severity.…”