Is choroidal vascularity index a useful marker in different stages of idiopathic epiretinal membranes?

Exploratory analysis of choriocapillaris vasculature as a biomarker of idiopathic epiretinal membrane

PURPOSE

To investigate the preoperative choriocapillaris perfusion (CCP) as a biomarker in patients with idiopathic epiretinal membrane (iERM).

MATERIALS AND METHODS

28 patients (28 eyes) with unilateral iERM who received pars plana vitrectomy (PPV) with internal limiting membrane (ILM) peeling were included for retrospective observational study. Optical coherence tomography (OCT) and angiography (OCTA) was performed before and after PPV. Area, perimeter, and circularity of superficial foveal avascular zone (FAZ) were analyzed preoperatively in both eyes using OCTA. Preoperative CCP was also analyzed with binarized en-face OCTA images. Measurements of best-corrected visual acuity (BCVA) and central foveal thickness (CFT) by OCT were conducted at the baseline and 6 months following the surgery. The correlations of preoperative OCT parameters with postoperative BCVA and CFT reduction were analyzed.

RESULTS

CCP was significantly lower (p < 0.001) and FAZ had shrunk (p < 0.001) in eyes with iERM compared to unaffected fellow eyes before surgery. BCVA and CFT became significantly improved after surgery (p = 0.001, p < 0.001). Multiple regression analysis revealed that preoperative CCP was significantly related with BCVA improvement (β = 0.185, p = 0.005), postoperative BCVA (β = 0.108, p = 0.023) and ratio of post- to preoperative CFT (β = 0.106, p = 0.044).

CONCLUSIONS

Preoperative CCP is a biomarker for poor functional and anatomical prognosis after surgery in iERM.

Choroidal Vascularity Index Fluctuations in Epiretinal Membranes in Vitreoretinal Surgery: Comparison Between Idiopathic and Diabetic Ones

Purpose

The aim of the study was to analyze choroidal vascularity index (CVI) fluctuations in patients with epiretinal membrane after vitreoretinal surgery, comparing idiopathic and secondary diabetic ones.

Methods

Thirty eyes suffering from idiopathic ERMs (I-ERMS; n = 15) and diabetic ERMs (D-ERMS; n = 15) were analyzed in this observational prospective study. Anatomical (central macular thickness) and functional (best-corrected visual acuity) parameters were analyzed preoperatively and at 1 and 3 months after vitrectomy. Perfusion findings regarding CVI and luminal area were also calculated.

Results

At 1 month after surgery, the luminal area and CVI significantly decreased in the I-ERMS group, whereas they were increased in the D-ERMS group. At the 3-month follow-up, the CVI tended to return to baseline values in I-ERMS and to reduce in D-ERMS, but without any statistical differences.

Conclusions

The significant change in the CVI after surgery seems to imply that the choroidal layer is affected by vitreomacular disease and can become a novel potential biomarker of predictiveness in vitreoretinal surgery.

Translational Relevance

The aim of the study was to focus on the early choroidal changes to better understand initial predictive elements of long-term functional postoperative outcomes.

Choroidal vascularity index changes in different treatments for vitreomacular traction

INTRODUCTION

The aim of this study was to examine if choroidal vascularity index (CVI) is different in eyes with unilateral vitreomacular traction (VMT) from their healthy fellow eyes; and whether different treatments affect the CVI.

METHODS

The baseline and 8-week post treatment CVIs of 56 unilateral VMT patients that underwent spontaneous resolution (n = 30), vitreoretinal surgery (n = 16) or pneumatic vitreolysis (n = 10) were compared with fellow eyes using paired samples t-test. Partial correlation analyses correcting age and gender was used for calculations between treatment groups. P values < 0.05 were considered statistically significant.

RESULTS

The mean baseline CVI for VMT and control eyes had no statistically significant difference (p = 0.81, r= -0.38). The post traction release follow-up CVI of VMT eyes and contralateral eyes had no significant difference (p = 0.12, r = 0.49). In spontaneous resolution group, vitreoretinal surgery group and pneumatic vitreolysis group the baseline and follow up CVIs of VMT eyes were statistically similar (p = 0.72, p = 0.32 and p = 0.79 respectively).Spontaneous detachment patients' CVIs showed a 0.57±5.81% increase, vitreoretinal surgery group had a reduction of 1.098±4.76%, and the pneumatic vitreolysis patients showed a CVI reduction of 0.307±4.24%. However, none of these changes was found to be statistically significant when compared between the groups (p = 0.21, r = 0.02).

DISCUSSION

Previous studies have argued that vitreomacular traction might have a role on the choroidal changes seen in the vitreoretinal interface disorders. This study has shown that VMT alone does not cause any significant changes in choroidal vascular index pre or post traction release.

Comparison of the morphological characteristics of the choroidal sublayer between idiopathic macular holes and epiretinal membranes with automatic analysis

PURPOSE

To compare the choroidal sublayer morphologic features between idiopathic macular hole (IMH) and idiopathic epiretinal membrane (iERM) on spectral-domain optical coherent tomography (SD-OCT) using an automatic segmentation model.

METHODS

Thirty-three patients with idiopathic IMHs and 44 with iERMs who underwent vitrectomies were involved. The enhanced depth imaging mode of SD-OCT was used to obtain the B-scan image after single line scanning of the macular fovea. The choroidal sublayer automatic analysis model divides the choroidal into the choroidal large vessel layer, the middle vessel layer and the small vessel layer (LVCL, MVCL and SVCL, respectively) and calculates the choroidal thickness (overall, LVCL, MVCL and SVCL) and vascular index (overall, LVCL, MVCL and SVCL). The morphological characteristics of the choroidal sublayer in the ERM eyes and the IMH eyes were compared.

RESULTS

The mean choroidal thickness in the macular centre of the IMH eyes was significantly thinner than that of the ERM eyes (206.35 ± 81.72 vs. 273.33 ± 82.31 μm; P < 0.001). The analysis of the choroidal sublayer showed that the MVCL and SVCL macular centres and 0.5-1.5 mm of the nasal and temporal macula were significantly thinner in the IMH eyes than in the ERM eyes (P < 0.05), and there was a difference in the macular centre of the LVCL between the two groups (P < 0.05). In contrast, the choroidal vascular index of the macular centre in the IMH eyes was significantly higher than that in iERM eyes (0.2480 ± 0.0536 vs. 0.2120 ± 0.0616; P < 0.05). There was no significant difference in the CVI of other parts of the macula, the LVCL or MVCL between the two groups.

CONCLUSION

The choroidal thickness of the IMH eyes was significantly thinner than that of the iERM eyes, which was mainly observed in 3 mm of the macular centre and the MVCL and SVCL layers of the choroid. The choroidal vascular index of the IMH eyes was higher than that of the iERM eyes. These findings suggest that the choroid may be involved in the pathogenesis of IMH and iERM.

Choroidal morphologic and vascular features in patients with unilateral idiopathic epiretinal membranes: An optical coherence tomography analysis integrated with assessment of retinal layers

Introduction

Integrated analysis of retinal and choroidal morphologic and vascular features is urgently needed to examine whether and how these two elements interact with each other, thus contributing to visual impairment in patients with idiopathic epiretinal membranes (iERMs).

Methods

An observational retrospective study consisting of 181 patients diagnosed with unilateral iERM between August 2019 and July 2022 was carried out at Peking University Third Hospital. All patients underwent a standardized set of ophthalmologic examinations, including EDI-OCT and OCTA scanning, and were subsequently categorized into four stages according to current classification schemes based on their OCT findings. Altogether, 15 qualitative and quantitative parameters of both the retina (full-layer, inner and outer layers) and choroid were identified.

Results

The results revealed variations in the choroidal vascularity index (CVI) among different stages of iERMs (p < 0.001) for the first time. Distributions of retinal parameters across four stages of iERMs were validated. Correlation analysis between choroidal and retinal parameters showed that the CVI was associated with both inner and outer retinal morphologic biomarkers. Functional damage to retinal integrity was determined to be a strong contributor to visual acuity reduction in iERMs.

Discussion

This study complemented our present understanding of posterior segment structural and vascular alterations in iERMs.

Choroidal vascularity index changes with phacovitrectomy for vitreoretinal interface disorders

Purpose

Vitreomacular interface disorders have long been argued to change choroidal structure. The aim of this study was to determine the choroidal vascularity index (CVI) changes following internal limiting membrane peeling for epiretinal membrane (ERM) and full thickness macular hole (FTMH).

Methods

Fifty-nine patients with unilateral ERM and 56 with unilateral FTMH were included in the study. Axial length, pre- and post-surgery intraocular pressure, baseline and post-phacovitrectomy CVI were calculated and compared with the normal fellow eyes. To compare the baseline and the final measurements, Wilcoxon test was used. Mann-Whitney U test was used for independent data comparisons. Median and standard deviations were compared.

Results

Axial length, pre- and post-surgery intraocular pressure differences were insignificant between study and fellow eyes within all groups. CVI were significantly lower in post-vitrectomy study eyes of all groups compared with pre-surgery (P < 0.001). There were no significant changes before and after the surgeries in fellow eyes. Baseline CVI of ERM study eyes (median 65.90%) and FTHM study eyes (median 65.59%) did not differ significantly between groups (U = 1336, P = 0.07, r = 0.16).

Conclusion

There are conflicting results of vitreoretinal interface disorders CVI in the literature. In this study, both FTMH and ERM eyes showed reduced CVI postoperatively compared with the baseline. Preoperatively, there were no difference between study eyes and the fellow eyes.

Evaluation of choroidal circulation and stromal features in Graves' disease

PURPOSE

This study aimed to evaluate choroidal thickness (CT) and choroidal vascularity index (CVI) in patients with Graves' disease (GD) without ocular involvement.

METHODS

Fifty patients diagnosed with GD and 50 age and gender matched healthy control subjects were retrospectively evaluated. Measurements were taken from five different points on CT images. Choroid images were classified as lumen regions (LA) and stromal regions (SA) using the image binarization method. CVI was calculated by dividing LA by the total choroidal area (TCA). The effects of Thyrotropin Receptor Antibody (TRAb), age, GD duration, blood pressure, axial length measurements, and intraocular pressure were analyzed on CT and CVI measurements.

RESULTS

Mean age was 40.1 ± 13.5 years in the patient group and 39.3 ± 13.6 years in the control group (p = 0.89). There was no significant difference between the GD group and control group in terms of CT measurements. There was a significant difference between the mean CVI measurements of the GD group and control group (68.03 ± 3.41 and 66.62 ± 3.11, respectively) (p < 0.001). Univariate linear regression analysis revealed a positive correlation between TRAb and CVI (p = 0.013).

CONCLUSION

While there was no significant difference between the CT measurements of the GD group and the control group, the GD group had significantly higher CVI measurements.