Swept-source OCT reduces the risk of axial length measurement errors in eyes with cataract and epiretinal membranes

Aims

To compare the biometric data from partial coherence interferometry (PCI) and swept-source OCT (SS-OCT) in patients with age-related cataract and epiretinal membrane (ERM): ERM, ERM with foveoschisis and macular pseudohole.

Methods

49 eyes of 49 subjects including 36 ERM, 9 ERM foveoschisis and 4 macular pseudohole were analysed to evaluate the axial length (AL) measurements and the presence of AL measurement errors, defined basing on the shape of the biometric output graphs and on the concordance of AL values between instruments. Eyes with ERM were divided in four stages according to OCT features (i.e. presence/absence of the foveal pit, presence of ectopic inner foveal layers, disrupted retinal layers).

Results

The devices provided similar mean AL measurements in all subgroups, with differences <0.1 mm in 41/49 cases (83.6%). AL measurement errors were observed in ERM stages 3 and 4, characterized by ectopic inner foveal layers, and were significantly more frequent with the PCI (8/17, 47%) as compared with the SS-OCT device (2/17, 12%), p = 0.02. The refractive prediction error in cases with AL measurement errors was significantly greater using the PCI compared to the SS-OCT device (p<0.05).

Conclusion

Both devices provide reliable biometric data in the majority of patients and can be used in the preoperative assessment of patients with age-related cataract and ERM. In eyes with ectopic inner foveal layers, attention should be paid as AL measurement and refractive prediction errors may occur, more frequently with the PCI device.

Hyperreflective cystoid spaces in diabetic macular oedema: prevalence and clinical implications

AIMS

To analyse the prevalence and evolution of hyper-reflective cystoid spaces with decorrelation signal detected using optical coherence tomography angiography (OCTA) in diabetic macular oedema (DMO).

METHODS

A retrospective study of consecutive eyes with DMO imaged using OCTA over a 1-year period was conducted. All eyes with hyper-reflective cystoid spaces at baseline and at least 3 months of follow-up were included in a longitudinal analysis.

RESULTS

The prevalence of hyperreflective cystoid spaces with decorrelation signal was of 37% (61/165) in DMO eyes. Hyperreflective foci within hyperreflective cystoid spaces were observed in 85% of eyes. The longitudinal study included 33 eyes (10 observed and 23 treated with intravitreal anti-vascular endothelial growth factor), with a median follow-up of 15 months. The hyperreflective cystoid spaces resolved in 85% of eyes. The mean best-corrected visual acuity remained stable during the follow-up, even in the eyes achieving a resolution of the hyperreflective cystoid spaces. Hard exudates appeared in the area of resolved hyperreflective cystoid spaces in 33% of eyes.

CONCLUSION

Hyperreflective cystoid spaces detected by OCTA affected more than one-third of the DMO eyes. Their disappearance was not associated with any functional improvement and led to the formation of new hard exudate deposits in about one-third of the eyes.

Central serous chorioretinopathy: risk factors for serous retinal detachment in fellow eyes

Background/Aims

To assess risk factors for serous retinal detachment (SRD) in the fellow eye of patients with central serous chorioretinopathy (CSC) based on clinical data and multimodal imaging findings, including baseline late-phase indocyanine green angiography (ICGA).

Methods

Consecutive patients with unilateral CSC were retrospectively assessed. Inclusion criteria were the availability of late-phase ICGA and a spectral-domain optical coherence tomography (OCT) macular cube for both eyes at baseline and over 3 months. Subsequent OCT of fellow eyes was reviewed to detect the development of SRD during the follow-up. Baseline medical data and multimodal imaging findings were analysed using Kaplan-Meier survival curves (log-rank test).

Results

Sixty-eight patients with unilateral CSC were included. An SRD was detected in 19% of fellow eyes during a mean follow-up of 25.8±18.7 months. Hyperfluorescent plaques on midphase ICGA, hypofluorescent foci on late-phase ICGA, retinal pigment epithelium changes on fundus autofluorescence and fluorescein angiography abnormalities were associated with the occurrence of SRD (log-rank test; p<0.001, p=0.02, p=0.002 and p=0.001, respectively).

Conclusion

These results suggest that the fellow eyes with specific findings on multimodal imaging in patients with unilateral CSC should be carefully followed up for possible incidence of CSC.