Optical coherence tomography angiography analysis of choroidal microvasculature in various forms of diabetic macular edema

INTRODUCTION

Optical coherence tomography angiography (OCTA) research in diabetic macular edema (DME) has focused on the retinal microvasculature with little attention to the choroid. The goal of this study was to analyze the association between quantitative choroidal OCTA parameters and various forms of DME observed on optical coherence tomography.

METHODS

We conducted a retrospective study of 61 eyes of 53 patients with DME. DME was classified as early or advanced, and as sponge-like diffuse retinal thickening (DRT), cystoid macular edema (CME) or serous retinal detachment (SRD). Quantitative OCTA parameters (vessel density [VD] in the superficial capillary plexus [SCP], middle capillary plexus [MCP], deep capillary plexus [DCP] and choriocapillaris [CC]) were recorded.

RESULTS

The VD in the CC and SCP was significantly higher in patients with early DME compared to patients with advanced DME (P value<0.01). CC VD was lower in subjects with SRD compared to DRT and CME (P value<0.001). Moreover, it was lower in CME compared to DRT (P value<0.05). No statistical differences were found between VD in the MCP and DCP (P value>0.05). Furthermore, CC VD was lower in patients with increased retinal thickness, disruption of the ellipsoid zone (EZ) or external limiting membrane (ELM), and disorganization of the inner retinal layers (DRIL) (P value<0.05).

CONCLUSION

CC ischemia plays an important role in the pathogenesis of DME. We demonstrated a decrease in CC VD in patients with severe DME, SRD, retinal thickening, EZ and/or ELM disruption and DRIL.

Multimodal imaging in phototoxic maculopathy: description of findings in a series of 12 patients

OBJECTIVE

To study the differences between solar retinopathy (SR) and the maculopathy produced by laser pointer (LPM) using multimodal imaging.

METHOD

A retrospective series is presented of 20 eyes of 12 patients with injuries associated with light, 7 with SR-compatible injuries, and 5 with LPM. At diagnosis, a complete ophthalmological examination was performed, including visual acuity (VA), retinography, and spectral domain optical coherence tomography (OCT). The patients were followed-up for a mean period of 20 months.

RESULTS

LPM is common in paediatrics (mean age 15.60±1.5years), and SR affects patients of all ages (mean age 47.56±1.51years). VA at diagnosis in LPM is greater, and recovery is more complete than in solar retinopathy. In conventional retinography, SR is shown as a single lesion in the macular area (100% of cases), while LPM usually presents as multifocal lesions (86% of cases). Infrared reflectance makes this difference clearer. The main sign in OCT is the disruption of the ellipsoid layer and interdigitation zone. This sign is maintained over time, and its size is greater in the SR than in the LPM. Hyper-reflective columns and hyper-reflective reaction of the retinal pigment epithelium are associated with the acute phase.

CONCLUSIONS

LPM and SR show significant differences in the type of patient affected, as well as in the signs in multimodal imaging, as well as in functional impairment and their evolution.

Focal choroidal excavation: Clinical findings and complications

OBJECTIVE

To describe the clinical findings and its complications in 2 patients with focal choroidal excavation (FCE).

METHODS

A retrospective case-series including 4 eyes of 2 patients with FCE that underwent a comprehensive ophthalmological examination including slit-lamp examination, colour fundus photography, spectral-domain optical coherence tomography (SD-OCT), fluorescein angiography (FA), and indocyanine green angiography.

RESULTS

In the 2 patients, both the anterior and posterior segment evaluations were mostly normal despite the of presence yellowish spots in the macular area of the right eye of patient 1, and of a small yellowish elevated lesion with serous macular detachment in the macular area of the left eye in patient 2. At diagnosis, SD-OCT revealed a conforming FCE in patient 1, and in patient 2, an FCE with perilesional subretinal fluid and a neuroepithelium detachment, suspicious of FCE complicated with central serous retinopathy (CSCR). At one year of follow-up, patient 1 developed choroidal neovascularisation (CNV) over the focal choroidal excavation. FA and indocyanine green angiography examinations revealed areas with hypofluorescence in earlier frames, and a diffuse leakage in late frames. After ranibizumab injections, the SD-OCT of patient 1 revealed no active exudation, while patient 2 showed partial resolution of subretinal fluid.

CONCLUSIONS

FCE is a newly described entity of unclear aetiology. It is characterised by a choroidal excavation in eyes, with absence of posterior staphyloma, scleral ectasia, trauma, or retinal disease. Although most lesions remain stable, there could be an association with CRSC or CNV.