Clinical Analysis of Macular Choroidal Thickness in Pseudoexfoliative Glaucoma and Primary Open-Angle Glaucoma

Purpose. To evaluate the differences in macular choroidal thickness and volume among patients with pseudoexfoliative glaucoma (PXG), patients with primary open-angle glaucoma (POAG), and controls. Methods. A total of 50 PXG patients (50 eyes) and 56 POAG patients (56 eyes) were selected as the PXG group and the POAG group, respectively, in this case-control study. A total of 54 age-, gender-, IOP-, and axial length-matched healthy individuals (54 eyes) were selected as the control group. Enhanced-depth imaging-optical coherence tomography (EDI-OCT) was used to measure and analyze the choroidal thicknesses and volumes in 9 macular regions of all subjects. Results. The choroidal thicknesses in the central subfield (CSM), temporal inner macula (TIM), inferior inner macula (IIM), and temporal outer macula (TOM) and the mean macular choroidal thickness were significantly thinner in the PXG group than in the control group (all P < 0.05 ). The choroidal volumes in the TIM, IIM, and TOM and the mean macular choroidal volume were significantly smaller in the PXG group than in the control group (all P < 0.05 ). The choroidal thicknesses in the CSM and IIM and the mean macular choroidal thickness were significantly thinner in the PXG group than in the POAG group (all P < 0.05 ). The choroidal volumes in the IIM and TOM and the mean macular choroidal volume were significantly smaller in the PXG group than in the POAG group (all P < 0.05 ). Multivariable linear regression analysis showed that the mean macular choroidal thickness was significantly thinner in association with older subjects and longer axial length eyes. There was no association between the macular choroidal thickness of various macular regions and visual field mean defect (MD) in groups PXG and POAG (all P > 0.05 ). Conclusions. The macular choroidal thicknesses and volumes (inferior and temporal) in PXG patients were thinner and smaller than those in POAG patients and healthy individuals. The role of choroidal thickness changes in the course of PXG remains unclear. A future prospective study is needed to better define these changes in PXG patients.

Choroidal Volume Evaluation after Photodynamic Therapy Using New Optical Coherence Tomography Imaging Algorithm

To evaluate choroidal volume and thickness changes after photodynamic therapy (PDT) for chronic central serous chorioretinopathy (CSC). Chronic CSC eyes with a history of PDT were selected. Average choroidal volume, average choroidal thickness, the maximum and minimum choroidal thickness of the macula irradiated area and peripheral non-irradiated areas before and after one and three months of treatment were examined. A total of 14 patients with chronic CSC and 9 controls without any eye pathology were enrolled. The mean choroidal volume in CSC before and, and after one and three months of treatment were 2.36 (standard deviation: 0.70), 1.90 (0.69), 1.86 (0.66) mm3 for the central area, 1.25 (0.38), 1.14 (0.35), 1.13 (0.34) mm3 for superior nasal area, 1.47 (0.41), 1.28 (0.43), 1.26 (0.43) mm3 for superior temporal area, 1.07 (0.49), 0.95 (0.38), 0.93 (0.35) mm3 for inferior nasal area, 1.17 (0.38), 1.04 (0.32), 1.03 (0.33) mm3 for inferior temporal area. This study revealed the choroidal volume changes in a short period after PDT and a decrease in unirradiated choroidal volume was also shown after the treatment. The algorithm provided on the ARI Network enables to evaluate the choroidal changes quantitatively and qualitatively.

Quantitative Assessment of Three-Dimensional Choroidal Vascularity and Choriocapillaris Flow Signal Voids in Myopic Patients Using SS-OCTA

Purpose: To compare the choroidal vascularity of large- and middle-sized choroidal vessels and choriocapillaris (CC) perfusion in patients with different degrees of myopia using swept-source optical coherence tomography angiography (SS-OCTA). Methods: One hundred and thirteen people with myopia were enrolled. SS-OCTA was performed to analyze the choroidal vascularity and CC perfusion. Three-dimensional (3D) choroidal vascularity index (CVI) and choroidal luminal volumes (LV) were obtained by artificial intelligence segmentation of the choroidal lumen in Volume OCT images. CC perfusion was assessed by flow signal voids (FSVs). Results: In the macular, multiple linear regression model showed that choroidal thickness (CT), total choroidal volume, LV, and choroidal stromal volume were negatively correlated with axis length (AL), respectively (all p < 0.001). Three dimensional CVI was negatively associated with AL (p < 0.05). FSV% was positively correlated with age only (p < 0.001). Additionally, after adjustment for age and AL, FSV% had a significant negative correlation with CT (p < 0.05). Conclusion: Choroidal vascularity decreases gradually with increasing severity of myopia. The decrease of CC blood perfusion was related to a higher severity of myopia and the thinning of choroid.

Alterations in Choroidal Volume and Determinants of Choroidal Volume and Visual Acuity in Entire Macula-involved Myopic Retinoschisis

Background To evaluate alterations in the choroidal volume (CV) of eyes with entire macula-involved myopic retinoschisis (MRS) and to investigate predictive factors for CV and visual acuity. Methods This cross-sectional observational study recruited 32 MRS eyes, 52 non-MRS highly myopic eyes, and 55 emmetropic eyes. Retinal and choroidal morphological findings were obtained using SD-OCT. The CV of the three groups was compared, and factors associated with CV and BCVA were analyzed. Results The macular CV was significantly lower in MRS eyes than in emmetropic eyes (P < 0.0001) and in non-MRS highly myopic eyes (P < 0.05). The difference in CV for MRS eyes among the superior (0.34 ± 0.16 mm3), inferior (0.33 ± 0.17 mm3), nasal (0.27 ± 0.12 mm3) and temporal (0.34 ± 0.21 mm3) quadrants was not significant (P = 0.3755). Multivariate regression analysis showed that the total macular CV in MRS eyes was negatively correlated with axial length (P = 0.0459), decreasing by 0.19 mm3 for each millimeter of axial length. Refractive error and defects in the ellipsoid zone (EZ) were associated with BCVA in logMAR units (P = 0.0075 and 0.0002, respectively); BCVA decreased by 0.027 logMAR units for each diopter of myopia. The total macular retinal volume (RV) in MRS eyes with EZ defects was higher than that in eyes with intact or partially continuous EZs (P = 0.0460). Conclusion In MRS eyes, the choroid is thinner, the total macular CV deceases as the axial length increases, and the severity of myopia and the integrity of the EZ, associated with the schisic extent are predictors of visual acuity, and the decrease of the macular CV is not the influencing factor of the visual function.

Corneal cross-linking for keratoconus: Evaluation of the retina and choroid

Purpose: To investigate the possible structural changes of the central choroid and retina after collagen cross-linking (CXL) in patients with progressive keratoconus (KCN). Methods: Twenty-five eyes of 25 patients were included in this study. Patients underwent enhanced depth imaging optical coherence tomography (EDI-OCT) before and 1 month after CXL. The values for central macular thickness (CMT), subfoveal choroidal thickness (CHT), and choroidal volume (CHV) were evaluated. Results: CMT before and after CXL was 263.24 ± 16.25 μm and 263.20 ± 16.51 μm, respectively ( p = 0.98). CHT was 362.08 ± 36.80 μm and 367.84 ± 33.67 μm before and after CXL, respectively ( p = 0.26). CHV was 8.74 ± 0.33 mm3 and 8.68 ± 0.36 mm3 before and after CXL, respectively ( p = 0.11). There was no significant difference in the corrected distance visual acuity before and after CXL (0.06 ± 0.05 and 0.05 ± 0.05 logMAR, respectively, p = 0.65). Conclusion: Central retinal and choroidal thicknesses are not changed after corneal cross- linking.

Decrease in Choroidal Vascularity Index of Haller’s layer in diabetic eyes precedes retinopathy

IntroductionThe study aimed to evaluate Choroidal Vascularity Index (CVI) of Haller’s and Sattler’s layers and their relationships with choroidal and retinal thickness, volumes measured on enhanced depth imaging–optical coherence tomography (OCT) scans in the eyes of patients without diabetes, patients with diabetes with no diabetic retinopathy (DR) and patients with diabetes and DR.Research design and methodsRetrospective analysis of 165 eyes from 84 Singapore Indian Eye Study-2 study participants (group 1: no diabetes, group 2: diabetes with no DR and group 3: with DR). Groups 1 and 2 were matched by age and gender from group 3.ResultsIn the eyes of patients with diabetes without DR, the macular CVI of Haller’s but not Sattler’s layer was significantly reduced compared with eyes of patients without diabetes. Eyes with >5 years of diabetes have significantly decreased CVI of Sattler’s layers (mean difference=0.06 ± 0.10, p=0.04) and also decreased subfoveal choroidal volume (mean difference=0.89 ± 0.16 mm3, p=0.02), compared with those with ≤5 years of diabetes.ConclusionDiabetic eyes without DR had significantly lower CVI of macular Haller’s layer than those of healthy controls. With a longer duration of diabetes, CVI of subfoveal Sattler’s layer and choroidal volume continue to decrease, irrespective of diabetic control, suggesting that early diabetic choroidopathy mainly affects larger choroidal veins initially before medium-sized arterioles. The CVI of macular Haller’s layer could potentially be used as a marker on spectral domain OCT imaging in newly diagnosed patients with diabetes for the onset of DR and as a possible prognostication tool in diabetic eyes. Future prospective longitudinal studies in diabetic eyes would be useful in establishing the relationship between CVIs of Haller’s and Sattler’s layer with visual acuity as a marker of photoreceptor health and visual prognosis.

Analysis of choriocapillaris perfusion and choroidal layer changes in patients with chronic central serous chorioretinopathy randomised to micropulse laser or photodynamic therapy

PurposeThe purpose of this study was to investigate the signal changes in choriocapillaris flow deficits and choroidal thickness changes using swept-source optical coherence tomography angiography (OCTA) following different treatments.DesignA double-blind, randomised controlled trial.MethodsPatients with unilateral chronic central serous chorioretinopathy (CSC) were randomised to receive subthreshold micropulse laser therapy (MLT) or half-dose photodynamic therapy (PDT). Choroidal thickness and choriocapillaris flow deficit signals were investigated.ResultsEighteen patients were randomised into the MLT group and 15 patients into the PDT group. Areas with flow deficit signals were identified in all baseline OCTA images of the choriocapillaris, with mean areas of 0.420 and 0.465 mm2 in the MLT and PDT groups, respectively. These flow deficit signal areas were significantly reduced at 6 months (p=0.011) in the MLT group and at 3 months (p=0.008) in the PDT group. Patients from the PDT group were shown to have smaller flow deficit areas than patients from the MLT group at all time points after treatment (p=0.001, analyses of variance). The mean choroidal volume of the fovea showed a significant reduction at 1 month (p=0.003), 3 months (p=0.199) and 6 months (p=0.006) in the PDT group.ConclusionThe flow deficit areas identified in the choriocapillaris layer may suggest possible relative choroidal ischaemia. With measurement of choroidal volume reduction and faster rates of flow deficit area change, PDT has a stronger effect than MLT in promoting choriocapillaris recovery.