Adaptive Optics Imaging of Cone Mosaic Abnormalities in Acute Macular Neuroretinopathy

Abstract

 

Purpose

 

To assess the cone photoreceptor mosaic in acute macular neuroretinopathy(AMN) using adaptive optics(AO) imaging.

 

Methods

 

Four consecutive patients with AMN were evaluated by dilated funduscopic examination, near-infrared reflectance(IR), confocal scanning laser ophthalmoscopy(SLO), eye-tracked spectral-domain optical coherence tomography(SDOCT) and a flood-illuminated retinal AO camera. Correlations were made between IRSLO, SDOCT and AO images at baseline and follow-up in 3 patients. Microperimetry was performed and correlated with SDOCT and AO images in 1 patient.

 

Results

 

At presentation, the cone photoreceptor density was decreased at the level of the AMN lesions in AO images in all patients. The cone photoreceptor mosaic disruption was more widespread than the lesion detected by IRSLO and SDOCT. At complete resolution of the AMN lesion in IRSLO, there was incomplete recovery of cone photoreceptor mosaic in AO. In 2 cases, there was persistent cone damage in AO despite restoration of the ellipsoid zone integrity on SDOCT at last follow-up. The area of disruption in cone mosaic revealed characteristic appearance of RPE cells in AO and correlated well with both SDOCT and microperimetry findings.

 

Conclusions

 

Cone photoreceptor damage and reconstitution were documented in vivo at the cellular level in AMN using AO imaging. AO appeared more sensitive than combined IRSLO and SDOCT to detect and follow photoreceptor damage in AMN patients. There was some irreversible cone photoreceptor damage in the 4 patients evaluated.

 

 

Multimodal imaging of 43-year-old female with AMN. AMN lesion appears dark with IRSLO(A). SDOCT showed hyperreflectivity of ONL/OPL and ellipsoid zone disruption(B). AO showed cone mosaic disruption(C) and cone density decrease(D) in an area extending beyond the limits of the lesion seen on IRSLO. After 3 months, the lesion resolved by IRSLO(E). SDOCT showed restoration of integrity of ellipsoid zone(F). AO showed partial recovery of cone mosaic(G) with incomplete restoration of cone density(H).

 

 

Multimodal imaging of a 67-year-old female with history of AMN. SDOCT showed subtle disruption of ellipsoid zone(B) corresponding to scotoma on microperimetry(A). AO showed loss of cones despite lack of apparent lesion on IRSLO(C). Area of cone disruption in AO(in red) correlated closely with microperimetry(D). High magnification shows honeycombed appearance of RPE cells in areas of cone loss (E).

 

Keywords: 552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • 688 retina • 648 photoreceptors