Choroidal Vascularity Index (CVI)--A Novel Optical Coherence Tomography Parameter for Monitoring Patients with Panuveitis?

Recent updates in choroidal imaging biomarkers

The choroid, a highly vascularized tissue, supplies the outer retina and is responsible for other functions such as thermoregulation, secretion of growth factors, and possibly emmetropization. Choroidal changes, therefore, may play a role in various chorioretinal diseases. The recent surge in publications focusing on the choroid can be attributed to improvements in both resolution and field of view of optical coherence tomography (OCT) and indocyanine green angiography (ICGA). Advancements in imaging have transitioned from manual to semi-automated and now fully automated methods for qualitative and quantitative choroidal analysis. These qualitative parameters include choroidal vascular patterns and focal or diffuse changes in the vascular wall, either bulbosity or tortuosity. Quantitative parameters include choroidal thickness, volume, vascularity index, contour, three-dimensional vessel quantification, and blood flow measurements using laser Doppler holography. We discuss these qualitative and quantitative biomarkers in detail, i.e., the underlying principles, clinical use, changes in normal and disease states, and their limitations. This will provide invaluable insights to clinicians in understanding the choroidal changes in physiological and pathological states.

Comparison of choroidal vascularity index in rhegmatogenous retinal detachment: impact of silicone-oil vs. gas tamponade following pars plana vitrectomy

PURPOSE

This study aimed to evaluate the impact of silicone oil (SO) and perfluoropropane gas (C3F8) tamponade on the choroidal vascularity index (CVI) in patients undergoing pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD).

METHODS

This retrospective study included 106 patients (212 eyes) with macula-off RRD who underwent PPV with either SO (n = 60) or C3F8 gas (n = 46) tamponade. CVI and other choroidal parameters, including luminal area (LA), stromal area (SA), total choroidal area (TCA), and subfoveal choroidal thickness (SFCT), were evaluated using swept-source optical coherence tomography (SS-OCT) and compared between operated and fellow healthy eyes at postoperative months 1 and 3. In addition, direct comparisons were made between SO- and gas-treated eyes to assess the differential impact of tamponade type on choroidal metrics. Multiple linear regression analyses were conducted to investigate associations between CVI and clinical variables such as preoperative best-corrected visual acuity (BCVA), age, sex, surgical type, and tamponade type.

RESULTS

No significant differences in CVI, LA, SA, or TCA were observed between operated and fellow eyes in either the SO or gas groups. Likewise, CVI values did not differ significantly between postoperative months 1 and 3 or between tamponade groups (p > 0.05). However, LA, SA, and TCA were significantly higher in SO-treated eyes than in gas-treated eyes at both follow-up visits (p < 0.05). SFCT significantly increased at month 1 in gas-treated eyes compared to fellow eyes (p < 0.001), but this difference was not significant by month 3. Conversely, SFCT was significantly lower in SO-treated eyes than in fellow eyes at both time points and continued to decrease following SO removal. The multiple linear regression analyses revealed no statistically significant associations between CVI values and preoperative BCVA, age, sex, surgical type, or tamponade type at either postoperative month 1 or month 3 (p > 0.05).

CONCLUSION

CVI values did not significantly differ between eyes treated with SO and gas tamponade, nor did they correlate significantly with postoperative visual outcomes. Although CVI provides valuable insights into choroidal health, it may not serve as a strong predictor of visual recovery in the early postoperative period. Larger, prospective studies are needed to further explore the long-term effects of different tamponade agents on choroidal vascularity and visual outcomes.

CLINICAL TRIAL NUMBER

Not applicable.

Choroidal profile in patients with inactive thyroid-associated ophthalmopathy

BACKGROUND

Thyroid associated ophthalmopathy (TAO) is a common autoimmune condition affecting orbital tissues. In this study, we aim to explore the alterations in choroidal vasculature during inactive phases of TAO by assessing choroidal vascularity index (CVI) and subfoveal choroidal thickness (SFCT) in these patients.

METHODS

In this cross-sectional comparative case series, enhanced-depth imaging optical coherence tomography (EDI-OCT) images were utilized to compare SFCT and CVI between patients with inactive TAO and age- and sex-matched normal individuals. For CVI assessment, foveal scans underwent binarization using the ImageJ software, with calculations based on the ratio of c (LA) to total choroidal area (TCA). Additionally, we investigated the associations between SFCT or CVI and factors such as age, gender, clinical activity score (CAS), proptosis, duration of disease, and margin to reflex distance (MRD).

RESULTS

The study included 50 eyes of 37 patients with inactive TAO (mean ± standard deviation (SD) age: 47 ± 11 years) and 282 eyes of 141 healthy individuals (mean ± SD age: 61 ± 11 years). SFCT and CVI were significantly higher in the TAO group compared to the control group (409.5 ± 152.7 μm vs. 249.3 ± 71.2 μm and 0.684 ± 0.037 vs. 0.629 ± 0.038, p < 0.001 for both). There was a significant negative association between age and SFCT in both univariate and multivariate analysis (r = -0.392, p = 0.003 and β = -0.04, p < 0.001, respectively). In multivariate analysis, we also noted a significant negative association between age and CVI (β = -0.09, p < 0.001). Apart from the correlation between MRD2 and SFCT (r = 0.297, p = 0.038 in univariate analysis and β = 38.15, p = 0.028 in multivariate analysis), no significant associations were observed between CVI or SFCT and clinical parameters in the TAO group (p > 0.05).

CONCLUSIONS

SFCT and CVI were significantly higher in the inactive TAO group compared to healthy controls. Although SFCT was significantly affected by age, no relationship was observed between CVI and physiologicical or disease-related parameters in univariate analysis. These findings accentuate the complexity of choroidal remodeling in TAO and emphasize the multifactorial nature of its pathogenesis. Further investigations are warranted to elucidate the underlying mechanisms driving these observed alterations and their clinical implications in managing individuals with TAO.

Relationship between choroidal structure and myocardial collateral flow regulation in acute and chronic coronary heart disease

PURPOSE

This study aimed to evaluate the relationship between coronary collateral filling, collateral size, and choroidal parameters in patients with acute and chronic coronary heart disease (CHD).

METHODS

Thirty-eight patients with acute CHD and 38 with chronic CHD who underwent diagnostic angiography in a cardiology clinic were included in this observational cross-sectional study. The control group comprised 32 healthy participants, and we examined both eyes of all participants. Diagnostic coronary angiograms were used to score the coronary collaterals, and choroidal parameters were measured in patients with CHD.

RESULTS

Choroidal vascular index (CVI) and subfoveal choroidal thickness (SFCT) were significantly lower in the chronic CHD group than in the acute CHD and control groups (p < 0.05). In the multinominal logistic regression analysis, collateral size had a significant association with both CVI (OR, 0.751; 95% CI, 0.596-0.947), and SFCT (OR, 0.986; 95% CI, 0.976-0.996) in patients with chronic CHD (p < 0.05). However, in the acute CHD group, no significant relationship was observed among choroidal parameters, collateral size, and filling.

CONCLUSION

Patients with chronic CHD had the lowest mean CVI and SFCT among the three groups, and this may be helpful in indicating chronic myocardial ischaemia. Moreover, an association was observed between larger collateral size and reduced CVI and SFCT in patients with chronic CHD, which may potentially be triggered by decreased angiogenic factors.

Is there a link between choroidal and retinal parameters in patients with systemic sclerosis? A prospective study

PURPOSE

Systemic sclerosis (SSc) is an autoimmune connective tissue disease. It affects choroid causing reduction in its thickness and volume. The aim of this study has been to get a better insight into the pathogenesis of retinal and choroidal involvement in SSc.

METHODS

This prospective single-center cross-sectional study included 33 patients with SSc and 40 controls. A full ophthalmological and rheumatological assessment was performed. The patients underwent the spectral-domain optical coherence tomography. The thickness of the inner retinal and outer retinal layer (ORL), outer nuclear layer (ONL), retinal pigment epithelium (RPE) was evaluated, as well as the central macular choroidal thickness and choroidal vascularity index (CVI).

RESULTS

The inner retinal thickness did not differ. In the outer retina, slight differences were observed in the thickness of the RPE and ORL within the inner temporal subfield, that were thinner in SSc patients, p<0.05. Choroidal parameters differed between the groups (luminal, stromal, and total choroidal areas; central choroidal thickness, p<0.05 for all). Correlations were found in the SSc patients (diffuse cutaneous systemic sclerosis group: the central macular ORL with the CVI rho=0.47, p=0.042; limited cutaneous systemic sclerosis group: the central macular RPE thickness with the total choroidal area rho=-0,7, p=0038, and with the luminal area: rho=-0,7, p=0036). The univariate regression analyses revealed only few significant associations with low fit of models to the data of the central macular ORL, ONL, RPE with the tested ocular and clinical parameters in the SSc and the controls.

CONCLUSION

It is plausible to assume that, although reduced in the SSc patients, the choroidal blood supply to the outer retina may still be sufficient to maintain its thickness.

Comparison of choroidal thickness and vascularity in patients with subretinal drusenoid deposits and large drusen using swept-source optical coherence tomography

PURPOSE

The aim of this study is to assess the choroidal features in patients diagnosed with non-advanced age-related macular degeneration (AMD) using Swept-source Optical Coherence Tomography (SS-OCT) and compare the findings of those with subretinal drusenoid deposits (SDD) and those with large drusen.

METHODS

Individuals aged 50 years and above, presenting with either SDD or large drusen alongside non-advanced AMD, underwent a thorough ophthalmic assessment. OCT scans were acquired using SS-OCT. Choroidal thickness (CT) maps within the early treatment diabetic retinopathy study (ETDRS) subfields were obtained. Choroidal vascularity index (CVI) was obtained from a foveal horizontal OCT scan, and it was determined as the ratio of luminal area to the total choroidal area. The data obtained were compared between the groups.

RESULTS

Forty-three eyes of 27 patients with SDD and 40 eyes of 21 patients with large drusen were included in the study. The mean age was 72.0 ± 8.6 years in the SDD group and 71.3 ± 5.6 years in the large drusen group with no significant difference (p = 0.717). In the choroidal thickness maps CT and CT in all ETDRS subfields were significantly lower in SDD group compared to the large drusen group. CVI values were not significantly different between SDD (0.628 ± 0.18) and large drusen groups (0.629 ± 0.20) (p = 0.812).

CONCLUSION

Non-advanced AMD patients with SDD exhibited reduced choroidal thickness compared to those with large drusen. Choroidal vascularity index did not significantly differ, suggesting that choroidal thickness may play a more substantial role than vascularity changes in the pathogenesis of SDD.

Assessment of choroidal vascularity index in juvenile idiopathic arthritis: implications for disease monitoring

PURPOSE

Juvenile Idiopathic Arthritis (JIA) can affect ocular structures, but choroidal involvement is not well understood. This study investigates the Choroidal Vascularity Index (CVI) in JIA patients compared to healthy controls and explores its relationship with disease activity.

METHODS

In this cross-sectional study, 35 JIA patients and 40 healthy controls underwent comprehensive ophthalmic examination and swept-source optical coherence tomography (SS-OCT). CVI, central macular thickness (CMT), and subfoveal choroidal thickness (SFCT) were measured. The Juvenile Arthritis Disease Activity Score (JADAS) was calculated for JIA patients. Statistical analysis included comparison between groups and correlation analysis.

RESULTS

JIA patients showed significantly lower CVI compared to controls (68.3 ± 2.5% vs. 72 ± 4.6%, p < 0.001). No significant difference was found in SFCT. CVI demonstrated a moderate negative correlation with JADAS (r = -0.368, p < 0.05). However, receiver operating characteristic (ROC) analysis revealed poor diagnostic performance of CVI for detecting JIA (AUC = 0.25).

CONCLUSION

The study reveals reduced choroidal vascularity in JIA patients and a correlation between CVI and disease activity. While CVI shows limited diagnostic utility, it may serve as a potential marker for monitoring inflammatory burden and treatment response in JIA. Further research is needed to establish its clinical utility fully.

Genetic influence on choroidal vascularity index

PURPOSE

To investigate the heritability of genetic influence on macular choroidal vascularity index (CVI).

METHODS

Total choroidal area (TCA), luminal area (LA), and CVI was measured using horizontal scan of spectral-domain optical coherence tomography with enhanced depth imaging in the 373 healthy twin participants. Characteristics of the participants were investigated, including age, sex, axial length, hypertension, diabetes, drinking habits, and smoking status. Univariate and subsequent multivariate regression analyses were performed to evaluate the associations of these factors with TCA, LA, and CVI.

RESULTS

Patients who were older and had a higher intraocular pressure, higher diastolic blood pressure, and lower pulse pressure showed associations with lower CVI (p<0.001, p = 0.014, p = 0.005, and p = 0.015, respectively). The covariate-adjusted heritability (±standard error) of the CVI was 0.716 ± 0.091, and the heritabilities of the TCA and LA were 0.691 ± 0.089 and 0.634 ± 0.100, respectively.

CONCLUSION

The TCA, LA, and CVI are highly heritable.

A novel multi-scale and fine-grained network for large choroidal vessels segmentation in OCT

Accurate segmentation of large choroidal vessels using optical coherence tomography (OCT) images enables unprecedented quantitative analysis to understand choroidal diseases. In this paper, we propose a novel multi-scale and fine-grained network called MFGNet. Since choroidal vessels are small targets, long-range dependencies need to be considered, therefore, we developed a two-branch fine-grained feature extraction module that can mix the long-range information extracted by TransFormer with the local information extracted by convolution in parallel, introducing information exchange between the two branches. To address the problem of low contrast and blurred boundaries of choroidal vessels in OCT images, we developed a large kernel and multi-scale attention module, which can improve the features of the target area through multi-scale convolution kernels, channel mixing and feature refinement. We quantitatively evaluated the MFGNet on 800 OCT images with large choroidal vessels manually annotated. The experimental results show that the proposed method has the best performance compared to the most advanced segmentation networks currently available. It is noteworthy that the large choroidal vessels were reconstructed in three dimensions (3D) based on the segmentation results and several 3D morphological parameters were calculated. The statistical analysis of these parameters revealed significant differences between the healthy control group and the high myopia group, thereby confirming the value of the proposed work in facilitating subsequent understanding of the disease and clinical decision-making.

Assessment of interocular symmetry of choroidal vascularity index and thickness in patients with systemic sclerosis: a prospective study

Purpose

Systemic sclerosis (SSc) affects blood vessels, internal organs, and skin. In ophthalmology, SSc impacts the choroid. The choroidal vascularity index (CVI) measures the vascular component of the choroid and may serve as a biomarker for the disease staging and prognosis. Studies have reported reduced choroidal thickness and altered CVI in SSc, which supports the theory of vascular damage. This study aimed to examine interocular symmetry in choroidal parameters among SSc patients. It has provided the insight into the disease symmetry and assessed the representativeness of examining one eye.

Methods

This prospective single-center cross-sectional study included 33 patients with SSc and 40 healthy controls. The patients underwent ophthalmological examination (including refraction, visual acuity, IOP, biometry, slit-lamp biomicroscopy, dilated fundus examination, and spectral-domain optical coherence tomography) and rheumatological evaluation. Various parameters of the choroid in the macular and peripapillary regions were analyzed, including choroidal thickness, choroidal volume, and CVI. The interocular asymmetry in the choroidal parameters was quantified using signed and absolute differences. The correlation analysis between the left and right eyes was based on the intraclass correlation coefficient (ICC), Spearman's correlation coefficient, and paired Wilcoxon test.

Results

There were no significant differences in the macular and peripapillary choroidal parameters between fellow eyes in both SSc patients and controls (p > 0.05). The parameter that showed the lowest correlation among those examined was CVI-in both groups, as well as in both examined areas. The interocular correlation of choroidal parameters was stronger in the peripapillary area than in the macular area in both groups. In general, the results were confirmed in subgroup analyses stratified according to sex, SSc subtype, Scl70 antibody positivity and previous and/or active digital ulcers.

Conclusion

There is interocular symmetry of the choroidal parameters in patients with SSc and controls included in our study. The parameters from one eye are representative of the fellow eye of a given patient. This conclusion may contribute to the design and interpretation of future studies. It also broadens our knowledge of SSc pathophysiology.

Evaluation of Choroidal Thickness and Choroidal Vascularity Index in Patients with Rheumatoid Arthritis

PURPOSE

To evaluate the choroidal vascularity index and choroidal thickness in patients with rheumatoid arthritis.

METHOD

This study is a case control study. Our study consists of a total of two groups, with 32 individuals diagnosed with rheumatoid arthritis (RA) and 32 healthy volunteers. The thickness of the subfoveal choroid was measured from the 500 micron (µm), 1000 µm, 1500 µm nasal aspect of the fovea, and 500µm, 1000µm, 1500 µm temporal and subfoveal thickness of the fovea. ImageJ version 1.53i (National Institutes of Health, Bethesda, MD, USA) from open access was used for choroidal vascular index calculation.

RESULTS

The mean age (p = 0.064) and gender distribution (p = 0.522) were not statistically different between these two groups. There was no difference between the groups in terms of visual acuity (p = 0.060), intraocular pressures (p=0.056), refractive errors (p = 0.418), and axial lengths (p = 0.280). Temporal 500 µm CT (p = 0.038), temporal 1000 µm CT (p = 0.010), and temporal 1500 µm CT (p = 0.005) differed significantly between the groups. The luminal area was significantly different between the RA group (842.71 ± 192.77) and the control group (957.78 ± 230.83) (p = 0.034). The choroidal vascularity index showed a significant difference between the RA group (64.99 ± 4.71) and the control group (67.34 ± 3.40) (p = 0.026). A significant difference was observed between the seronegative RA and the control group with temporal 1500 µm CT (p = 0.030), temporal 1000 µm CT (p = 0.023), and luminal area (p = 0.034).

CONCLUSION

We demonstrated thinning in CT and decreased CVI for the first time in RA patients by comparing it with the control group.

Ultrastructural imaging biomarkers in diabetic macular edema: A major review

Diabetic macular edema (DME) is a vision-threatening complication of diabetic retinopathy and causes significant morbidity in patients. Anti-vascular endothelial growth factor (VEGF) agents are the mainstay of treatment for DME, with steroid implants being used for the treatment of anti-VEGF resistant eyes. Over the years, several classification systems have been devised to describe the patterns of DME using optical coherence tomography (OCT). With the advent of effective treatments, it has become imperative that imaging cues are not merely used for classifying the disease but also as biomarkers for prognostication of disease activity and treatment response. In this aspect, newer imaging findings such as hyperreflective dots, photoreceptor integrity, and disorganization of retinal inner layers have been characterized in detail by several authors. Macular perfusion analysis using OCT angiography is the latest in the armamentarium for imaging DME. In this narrative review, we have summarized all relevant literature related to the ultrastructural imaging-based biomarkers of DME and their correlation to treatment.

Ocular effects of synthetic cannabinoids: a case-control study

OBJECTIVE

To evaluate the ocular effects of "Bonzai", a synthetic cannabinoid (SC), in seropositive and seronegative users.

METHODS

Sixty eyes of 60 consecutive male patients with a history of "Bonzai" use and 30 eyes of 30 age-matched male healthy controls were enrolled in this case-control study. Patients with past "Bonzai" use were grouped as seropositive (n:30) and seronegative (n:30) according to urine toxicology tests. All groups were compared for blood pressures, intraocular pressure, foveal and parafoveal retinal thicknesses, subfoveal and parafoveal choroidal thicknesses, measurements of the peripapillary retinal nerve fibre layer (RNFL), and macular ganglion cell complex (GCC), subfoveal total choroidal, luminal and stromal areas, and choroidal vascularity index (CVI).

RESULTS

No differences were noted in blood pressures between the groups (p > 0.05). The mean intraocular pressure was significantly lower in the seropositive group than in the other groups (p < 0.001). Foveal and retinal thicknesses, RNFL, and GCC measurements did not differ between the groups (p > 0.05). Subfoveal and parafoveal choroidal thicknesses and areas were lower in the seropositive group than in the other groups (p < 0.001, for all). CVI increased in both groups with "Bonzai" use compared to the control group (p < 0.001, for all).

CONCLUSIONS

This study indicates that intraocular pressure may decrease, and choroidal changes may be observed in SC users. Further clinical studies with a larger sample size, especially using purified SC for therapeutic purposes, are needed to confirm the present findings, and further histopathologic studies are required to clarify the changes in the choroid despite SC seronegativity.

CLINICAL TRIAL ID

NCT06235346.

Effects of Alpha-Lytic Therapy Withdrawal on Choroidal Parameters in Intraoperative Floppy Iris Syndrome High-Risk Patients

Background/Objectives: The aim of this study is to investigate the effect on choroidal parameters of drug withdrawal in patients taking α1 adrenergic receptor antagonist (ARA) inhibitors. Methods: In total, 32 eyes of 32 patients under alpha-lytic therapy, and 32 eyes of 32 control subjects, both scheduled for cataract surgery in the fellow eye, were included. EDI-OCT was performed in all patients and subfoveal choroidal thickness (SFCT), luminal choroidal area (LCA), stromal choroidal area (SCA), total choroidal area (TCA), and choroidal vascularity index (CVI) during the preoperative visit were compared with data approximately 1 month after alpha-lytic withdrawal. The same assessments were performed in the control group. Results: SFCT and LCA were significantly reduced in the patients 1 month after alfa-lytic therapy withdrawal (p < 0.05), whereas in the control group, no changes in choroidal parameters were observed. Conclusions: The data proved that α1ARA inhibitors affected choroidal vessels, whereas no modification of choroidal stroma was observed.

Angioarchitectural alterations in the retina and choroid in frontotemporal dementia

OBJECTIVE

Frontotemporal dementia (FTD) is a progressive neurodegenerative disorder that affects the frontal and temporal lobes of the brain, leading to cognitive decline and personality changes. The objective of this cross-sectional study was to characterize angioarchitectural changes in the retina and choroid of individuals with FTD compared to cognitively normal controls using optical coherence tomography (OCT) and OCT angiography (OCTA).

METHODS

Cross-sectional comparison of patients with FTD and controls with normal cognition. All participants underwent Mini-Mental State Examination (MMSE) at the time of imaging. Outcome measures included OCT parameters: retinal nerve fiber layer (RNFL) thickness, ganglion cell layer-inner plexiform layer (GC-IPL) thickness, central subfield thickness (CST), subfoveal choroidal thickness (SFCT), choroidal vascularity index (CVI); and OCTA superficial capillary plexus parameters: foveal avascular zone (FAZ) area, 3x3mm and 6x6mm macular perfusion density (PD) and vessel density (VD), 4.5x4.5mm peripapillary capillary perfusion density (CPD) and capillary flux index (CFI). Generalized estimating equation analysis was used to account for the inclusion of 2 eyes from the same participant.

RESULTS

29 eyes of 19 patients with FTD and 85 eyes of 48 controls were analyzed. In FTD, 3x3mm macular PD (p = 0.02) and VD (p = 0.02) and CFI (p = 0.01) were reduced compared to controls. There was no difference in average 4.5x4.5mm CPD, RNFL thickness, GC-IPL thickness, CST, SFCT, CVI, FAZ, or 6x6mm VD or PD between FTD and controls (all p > 0.05); however, there was a trend toward lower macular 6x6mm PD and VD in patients with FTD.

CONCLUSION

Decline of peripapillary and macular OCT and OCTA parameters merit further investigation as potential biomarkers for FTD detection. Noninvasive retinal and choroidal imaging may hold promise for earlier detection, and future longitudinal studies will clarify their role in monitoring of FTD.

Age related grid-wise spatial analysis of choroidal parameters in well characterised healthy population

Choroidal vascularity index (CVI) is an image-based metric applied to assess the choroid in disease but poorly explored in natural aging. In this retrospective cohort study, we assessed a single eye of 309 healthy individuals from 20 to 70 + years, and quantified spatial topography of total choroidal area (TCA), luminal area (LA), stromal area (SA) and CVI (LA: TCA) in cluster and standard retinal templates using a semi-automated approach. CVI was found to be greatest in the central vs. periphery (CVIcentral 67.08% [66.85-67.73] vs. CVIperiphery65.68% [65.32-66.01], p < 0.01). In this study, CVI also showed no significant change with age or physiological factors. Area parameters demonstrated greater magnitude in the central versus periphery but with a superior bias: TCAsuperior 0.227mm2 [0.223-0.233] vs. TCAinferior 0.207mm2 [0.201-0.213], p < 0.01.They also showed a linear decline with age (TCA:-0.00112 to -0.00169 mm2/year; LA: -0.00074 to -0.00112 mm2/year; SA: -0.00039 to -0.00056 mm2/year, p < 0.0001), with a higher rate of decline inferiorly (p < 0.001). This study demonstrates that CVI exhibits specific spatial differences across macula, independent of age. It further establishes a comprehensive, normative database of CVI and other choroidal angioarchitecture metrics which is a valuable resource for distinguishing pathological changes from normal age-related variations in future assessments of choroid-involving diseases.

Peripapillary and subfoveal choroidal vascular index in patients with tension-type headache and migraine

PURPOSE

This study aimed to evaluate the choroidal vascular characteristics of patients followed up with different headache diagnoses.

DESIGN

Prospective comparative study.

METHODS

This study included 21 patients with migraine with visual aura (MwA), 20 with migraine without aura, 29 patients experiencing episodic tension-type headache, and 30 healthy participants. The participants was performed refraction values, axial length, and intraocular pressure were examined. Choroidal thickness was determined in all participants with HD-line optical coherence tomography (OCT) in the subfoveal, nasal, and temporal quadrants 500 µm from the fovea. Using special image processing software, luminal area (LA), stromal area, total choroidal area, and choroidal vascular index (CVI) values were calculated in both macular and peripapillary regions. OCT was also used to perform peripapillary retinal nerve fiber layer (pRNFL) thickness and optic disc head measurements.

RESULTS

Spherical refraction, axial length, and intraocular pressure values did not significantly differ among the four groups with similar gender and age distributions ( P > 0.05). The LA values in both macular and peripapillary regions were found to be statistically significantly lower in the MwA group ( P = 0.007 and P = 0.005, respectively). There was no statistically significant difference among the groups in terms of the remaining choroidal area parameters or CVI values ( P > 0.05). The groups also did not show any significant difference in the pRNFL or optic disc head measurements performed in different quadrants ( P > 0.05).

CONCLUSION

While LA, one of the choroidal vascular parameters, was found to be lower in the MwA group in both the macular and peripapillary regions, there were no statistically significant differences between the groups in terms of the peripapillary or macular CVI values.

Investigation of choroidal thickness and choroidal vascularity index in ocular rosacea patients according to skin subtypes

BACKGROUND

To compare the choroidal thickness (CT) and choroidal vascularity index (CVI) values in ocular rosacea (OR) patients across skin subtypes of the disease and healthy controls.

METHODS

This prospective study included 90 eyes of 90 mild-moderate OR patients with different skin subtypes (30 phymatous, 30 papulopustular and 30 erythematotelangiectatic) and 30 eyes of 30 age-gender matched healthy volunteers. After obtaining the enhanced depth imaging optical coherence tomography images, the CT was measured at subfoveal, 1500 μm nasal and 1500 μm temporal to the fovea, and the CVI was calculated using Image J software in the subfoveal, nasal and temporal areas.

RESULTS

There was no CT significant difference between OR patients and healthy controls in all regions (p > 0.05). CVI values of OR patients were found to be significantly lower in the subfoveal, nasal and temporal regions compared to healthy controls (p = 0.02, p = 0.01, p = 0.01, respectively). No CT difference was detected between the subtypes and healthy controls in all regions (p > 0.05). Subfoveal-CVI was significantly lower in the phymatous subtype than the other subtypes and controls (p < 0.05), while nasal and temporal-CVI were significantly lower in the phymatous and papulopustular subtypes than the erythematotelangiectatic subtype and controls.

CONCLUSION

Our study demonstrated no difference between rosacea skin types and healthy controls in terms of CT. Phymatous and papulopustular subtypes were more likely to be affected by chronic inflammation with having lower CVI in most of the regions. Further studies are needed to investigate the association of inflammatory factors with CVI in OR.

Subclinical choroidal involvement in Systemic Lupus Erythematosus

PURPOSE

To assess the choroidal status of Systemic Lupus Erythematosus (SLE) patients using Optical Coherence Tomography (OCT) and OCT-Angiography.

METHODS

SLE patients with disease duration < 10 years, no disease activity and no ocular involvement were recruited and cross-sectionally evaluated. A demographically similar cohort of healthy subjects was used for comparison. The main outcome is choroidal vascularity index (CVI). As secondary outcomes, choriocapillaris parameters and choroidal thickness (CT) were evaluated.

RESULTS

Forty eyes of 40 subjects (20 SLE patients and 20 healthy subjects) were studied with a mean ± SD age of 36.7 ± 9.9 years. In the SLE group, the mean ± SD duration of disease was 7.35 ± 2.21 years. Increased CVI was found in the SLE group (p = 0.022). Considering the choriocapillaris, SLE patients presented a lower number (p = 0.037) and a smaller total area (p = 0.041) of signal voids. No differences between groups were found in CT. For SLE patients, CT at subfoveal, temporal and inferior locations presented a negative moderate correlation with disease duration. A strong correlation between choriocapillaris parameters and age was demonstrated for both groups.

CONCLUSIONS

This study provides evidence of subclinical choroidal changes in adult SLE patients with inactive disease and no overt ocular manifestation. Increased CVI and fewer and smaller flow voids in choriocapillaris with normal CT suggest increased choroidal vascularity in SLE.

Evaluation of Choroidal Structures in Children with Newly Diagnosed Type-1 Diabetes Mellitus

Objectives

The objective of this study was to evaluate the subfoveal choroidal thickness (SFCT) and choroidal vascularity index (CVI) in children with newly diagnosed type 1 diabetes mellitus (T1DM).

Methods

A total of 80 children (40 with T1DM and 40 healthy controls) were included in this cross-sectional study. Enhanced depth imaging optical coherence tomography (EDI-OCT) images of all participants were analyzed. The SFCT, total choroidal area (TCA), luminal area (LA), stromal area (SA), and CVI measurements were obtained from EDI-OCT images and compared between groups. The effects of HbA1c, fasting plasma glucose, and axial length measurements on choroidal measurements were investigated.

Results

There was no significant difference between the groups according to TCA (0.84 [0.57-1.26] vs. 0.88 [0.65-1.16] mm2, p=0.745), LA (0.55 [0.41-0.79] vs. 0.59 [0.43-0.74] mm2, p=0.745), SA (0.27 [0.15-0.47] vs. 0.28 [0.15-0.47] mm2, p=0.935), and CVI (68.03 [66.5-70.5] vs. 67.75 [66.2-69.5] %, p=0.794), respectively. However, T1DM patients had thinner SFCT compared to control subjects (309.0 [327-489] and 398.5 [219-491], p<0.044). No correlation was found between HbA1c, fasting plasma glucose, axial length measurements, and SFCT, TCA, LA, SA, or CVI.

Conclusion

Children with newly diagnosed T1DM have thinner SCFT in comparison to healthy children, however, no significant difference in CVI was observed between the groups. Long-term follow-up should be used to confirm the impact of the DM duration on CVI.

Choroidal vascularity features of fundus tessellation in adults with high myopia

BACKGROUND

To investigate alterations in choroidal vascularity index among highly myopic adults with fundus tessellation, utilizing optical coherence tomography.

METHODS

Total of 143 highly myopic adults (234 eyes) with fundus tessellation were collected in this cross-sectional study, which was stratified into different lesion groups based on the novel tessellated fundus classification. Subfoveal choroidal thickness (SFCT), choroidal luminal area (LA), stromal area (SA), total choroidal area (TCA), and choroidal vascularity index (CVI) were analyzed utilizing optical coherence tomography (OCT) with enhanced depth imaging (EDI) mode, enabling precise quantification of these parameters.

RESULTS

Comparison analysis demonstrated notable distinctions in spherical equivalent (SE), axial length (AL), and SFCT across the four tessellation grades (p < 0.001). Analysis of the choroidal vascularity parameters, including LA, TCA, and CVI, demonstrated notable disparities across the four groups (p < 0.001), while no significant variations were observed in SA when comparing Grade 1 versus Grade 2, as well as Grade 2 versus Grade 3 (p > 0.05). Logistic regression analyses illustrated that the higher grade of tessellated exhibited a positive association with AL (OR = 1.701, p = 0.027), while negatively associated with SFCT (OR = 0.416, p = 0.007), LA (OR = 0.438, p = 0.010) and CVI (OR = 0.529, p = 0.004). Multiple regression analyses demonstrated a significant negative association between CVI and both SE and AL after adjusting for age, while positively associated with SFCT (p < 0.05).

CONCLUSION

Subtle choroidal vascularity changes may have a meaningful contribution to the development and progression of fundus tessellation. CVI and LA dramatically decreased during the early stages of tessellation development and maintained a relatively stable status when in the severe tessellated grades.

Choroidal vascularity index and choroidal thickness assessment in vitiligo

CLINICAL RELEVANCE

Vitiligo is a skin disease characterised by depigmentation and loss of melanocytes. Melanocyte loss may not be limited to the skin in vitiligo, and various abnormalities may occur in the choroid, which is dense in melanocytes.

BACKGROUND

To evaluate structural changes in the choroid by measuring choroidal thickness and vascularity index using optical coherence tomography in patients with vitiligo and comparing them to healthy subjects.

METHODS

This study included 168 participants: 84 with vitiligo (30 females, 54 males) and 84 controls (36 females, 48 males). Choroidal thickness and vascularity index were measured using the enhanced depth imaging mode in spectral-domain optical coherence tomography. The choroidal thickness was measured at the following five points; subfoveal (SF), 500 μm (NCT1) and 1000 μm (NCT2) nasal to the fovea; and 500 μm (TCT1) and 1000 μm (TCT2) temporal to the fovea. The choroidal vascularity index was calculated using the ImageJ software.

RESULTS

SF (p < 0.001), NCT1 (p < 0.001), NCT2 (p = 0.021), TCT1 (p = 0.001), and TCT2 (p < 0.006) choroidal thicknesses were significantly smaller in the vitiligo group than in the control group. Total choroidal (p < 0.001) and stromal (p < 0.001) areas were significantly smaller in the vitiligo group than in the control group. Choroidal vascularity indices were significantly higher in the vitiligo group than in the control group (p < 0.001). However, luminal areas did not differ significantly between groups (p = 0.935).

CONCLUSION

Patients with vitiligo should be regularly monitored for choroidal alterations and, if necessary, referred to an ophthalmologist.

Effect of orbital decompression surgery on the choroidal profile in patients with thyroid eye disease

This study aimed to investigate the effect of orbital wall decompression surgery and reduction of proptosis on the choroidal vascularity index (CVI) and subfoveal choroidal thickness (SFCT) in patients with thyroid eye disease (TED). Fifty-one eyes from 38 patients with controlled TED and proptosis were enrolled in this study. The majority of the patients (50.9%) had a clinical activity score (CAS) of zero, and none had a CAS greater than 2. The patients underwent a complete baseline ophthalmologic examination, and their choroidal profile alterations were monitored using enhanced depth imaging optical coherence tomography (EDI-OCT) before and during the three months after surgery. Changes in SFCT, luminance area (LA), total choroidal area (TCA), and the choroidal vascularity index (CVI) were measured as the ratio of LA to TCA in EDI-OCT images. The participants had an average age of 46.47 years, and 22 were female (57.9%). The SFCT of the patients exhibited a significant reduction over the follow-up period, decreasing from 388 ± 103 to 355 ± 95 µm in the first month (p < 0.001) and further decreasing to 342 ± 109 µm by the third month compared to baseline (p < 0.001). The CVI exhibited a drop from 0.685 ± 0.037 at baseline to 0.682 ± 0.035 and 0.675 ± 0.030 at 1 and 3 months post-surgery, respectively. However, these changes were not statistically significant, indicating comparable decreases in both LA and TCA. There was a significant correlation between improved proptosis and reduction in SFCT (p < 0.001) but not with CVI (p = 0.171). In conclusion, during the three months of follow-up following orbital wall decompression, CVI did not change, while SFCT reduced significantly. Additionally, SFCT was significantly correlated with proptosis reduction, whereas CVI was not.

Effect of adalimumab on choroidal thickness and choroidal vascularity index in eyes with non-infectious uveitis using enhanced-depth imaging optical coherence tomography

OBJECTIVE

To evaluate the effect of adalimumab (ADA) on choroidal thickness (ChT) and choroidal vascularity index (CVI) in eyes with non-infectious uveitis (NIU).

METHODS

Thirty-seven eyes with NIU including Behçet disease (BD), sarcoidosis, ankylosing spondylitis (AS), juvenile idiopathic arthritis and idiopathic arthritis, 38 eyes of non-uveitic (NU) patients including BD, AS and rheumatoid arthritis, and 40 healthy control eyes were included. ADA was used for anti-TNF-naive adult (80 mg) or paediatric (40 mg) patients with refractory NIU, then 40 mg every 2-week (20 mg in children<30 kg) with controls at weeks 1, 4, 12, and 24. Images were used to measure central, nasal, and temporal ChT, and the luminal area (LA), stromal area, and total choroidal area (TCA) were analysed using enhanced-depth imaging optical coherence tomography (EDI-OCT) by ImageJ software. The CVI was then calculated as the ratio of LA to TCA.

RESULTS

Mean ages were similar between the groups. Mean (SE) subfoveal ChT measurements for each location were also similar (for each, p > 0.05). However, calculated CVI values in eyes with NIU (0.63 ± 0.007) were significantly (p < 0.001) lower than NU eyes (0.66 ± 0.006) and controls (0.70 ± 0.007) (p < 0.001). Moreover, CVI was significantly lower in NU eyes compared to controls (p < 0.001). There were no significant CVI changes between the consecutive visits after ADA therapy in eyes with NIU (for each, p > 0.05).

CONCLUSIONS

Decreased CVI in NIU and NU eyes indicates that systemic inflammation affects the choroidal vasculature and perfusion both in the presence and absence of ocular involvement. Although CVI may be used as a possible novel tool in monitoring ocular involvement and progression of NIU, CVI does not seem to be a biomarker for treatment monitoring in NIU.

Pachyvitelliform maculopathy: an optical coherence tomography analysis of a novel entity

PURPOSE

To describe the optical coherence tomography features of pachyvitelliform maculopathy (PVM), an acquired vitelliform lesion (AVL) associated with pachychoroid disease.

METHODS

This study was a retrospective, multicentre, observational analysis.Medical records and multimodal imaging were reviewed in all patients with pachychoroid disease and AVL. Visual acuity, central choroidal thickness (CCT), AVL dimensions, total choroidal area, luminal choroidal area, stromal choroidal area and choroidal vascular index were measured in all eyes with PVM and compared with normal age-matched control eyes.

RESULTS

Mean age of the PVM group (17 eyes of 17 patients) was 71.41 years. Average follow-up was 33.15 months. Baseline VA was 20/40 in the PVM group and declined to 20/100 (p=0.006). AVLs were all detected overlying pachyvessels with optical coherence tomography and were all hyperautofluorescent with fundus autofluorescent imaging. Mean CCT in the PVM group was significantly greater (352.35 µm) than the CCT in the control group (226.88 µm, p<0.001). Retinal pigment epithelium (RPE) disruption was present in 64.71% of eyes with PVM at baseline and 41.18% developed macular atrophy at the end of follow-up.

CONCLUSIONS

PVM, defined by the presence of AVL associated with pachychoroid features, is a distinct novel entity of the pachychoroid disease spectrum. This study suggests a possible pathogenesis of RPE dysfunction secondary to a thick choroid, leading to accumulation of undigested photoreceptor outer segments and AVL. Clinicians should be aware of this common cause of vitelliform lesions and the poor visual prognosis due to the high risk of atrophy development.

Macular choroidal thickness, volume, and vascularity index in patients with systemic sclerosis

PURPOSE

The aim of this study was to investigate choroidal parameters in patients with systemic sclerosis (SSc) using enhanced depth imaging spectral-domain optical coherence tomography (EDI-SD-OCT) and to determine their relationships with clinical variables and ocular features.

METHODS

Thirty-three patients with SSc and 40 controls were enrolled. The groups did not differ with regard to age, sex, and axial length. The mean choroidal thickness and volume were obtained in each conventional Early Treatment of Diabetic Retinopathy Study grid subfield. The choroidal vascularity index (CVI), which provides a quantitative analysis of vasculature by calculating the proportion of the luminal area (LA) to the total choroidal area (TCA), was determined.

RESULTS

Lower choroidal thickness and volume were observed in the SSc group. The CVI was significantly higher in SSc patients, whereas the TCA, LA, and stromal area were significantly lower in the SSc group; however, the significant difference of the stromal component was more pronounced than that of the luminal component. Regression analyses did not identify any clinical factors associated with the CVI (except Ca-blocker use), central macular thickness, or volume. No significant differences in choroidal parameters were found within the SSc subtypes (diffuse cutaneous systemic sclerosis (dcSSc) vs. limited cutaneous systemic sclerosis (lcSSc)), or between eyes stratified according to SSc pattern (early, active, or late) using nailfold capillaroscopy (p > 0.05 for all).

CONCLUSION

Our results, with notably higher CVI values, may shed new light on choroidal impairment in patients with SSc. Stromal involvement appeared to dominate the vascular component.

Choroidal Perfusion Changes After Vitrectomy for Myopic Traction Maculopathy

BACKGROUND

The choroidal vasculature supplies the outer retina and is altered in many retinal diseases, including myopic traction maculopathy (MTM). Choroid health is typically assessed by measuring the choroidal thickness; however, this method has substantial limitations. The choroidal vascularity index (CVI) was recently introduced to provide quantitative information on the vascular flow in the choroid. This index has been evaluated in a wide range of diseases but has not been extensively used to characterize MTM.

AIM

This study aimed to investigate the CVI across different stages of MTM and the influence of macular surgery on choroidal perfusion markers in different surgically resolved MTM stages.

METHODS

Eighteen healthy myopic eyes in the control group and forty-six MTM eyes in the surgical group were evaluated using enhanced optical coherence tomography (OCT) imaging. Binarized OCT images were processed to obtain the luminal choroidal area (LCA) and stromal choroidal area (SCA), which were used to calculate CVI in the form of a percentage ratio. CVI data were collected at baseline, one and four months postoperatively, and at the final clinical visit. MTM eyes were divided into four stages based on disease severity. The choriocapillaris flow area (CFA) and central subfield thickness (CSFT) were measured along side the CVI.

RESULTS

No significant differences were observed between the two groups at baseline, except for visual acuity (p  < 0.0001). Surgery significantly improved vision at all postoperative time points (p  < 0.0001). At baseline, there were no significant differences in CVI, CFA, or CSFT scores between the control and surgical groups. However, all three measurements were lower at the final visit in the surgical group (p ≤0.0001). No significant differences were found in any of the parameters among the four stages of MTM (p  > 0.05). Ultimately, correlation and multivariate linear regression analyses did not reveal any significant association between CVI and visual acuity.

CONCLUSIONS

This study did not find significant preoperative differences in CVI between healthy myopic eyes and eyes with MTM. However, the postoperative CVI and CFA values were significantly lower than those of the control eyes. Thus, CVI may not be a good biomarker for surgical outcomes, as the correlation between CVI and visual acuity was not statistically significant.The CVI and CFA decreased after surgery, providing evidence of choroidal changes after surgical management.

Ocular hemodynamics in epileptic children treated with antiepileptic drugs

PURPOSE

To evaluate the quantitative measurements obtained for vessel density (VD) of the optic nerve head, macula, peripapillary retinal nerve fibre layer (p-RNFL) and total retinal thicknesses (Trt) by optical coherence tomography angiography (OCT-A) and the choroidal vascular structure using an image binarization method in children with epilepsy using three different antiepileptic drugs (AEDs) and to compare these measurements with healthy participants.

METHODS

This observational, cross-sectional study included 124 patients divided into 4 groups: Group-1: patients receiving carbamazepine(n = 30), group-2: patients receiving levetiracetam (n = 31), group-3: patients receiving valproic acid (n = 32), and group 4: healthy controls (n = 31).A fully automated microstructural analysis of the VD of the retinal superficial capillary plexus (SCP), deep capillary plexus (DCP), and the choriocapillaris (CC) layers and radial peripapillary capillary, and Trt, p-RNFL thickness were analyzed by using OCT-A. Enhanced depth imaging (EDI)-OCT scans of the macula were obtained and the images were binarized using the ImageJ software.

RESULTS

The mean age, gender distribution and the duration of epilepsy were similar in all groups. Evaluation of the p-RNFL thickness and perifoveal Trt between the groups showed a statistically significant difference in all quadrants.The p-RNFL thickness was lower in patients receiving carbamazepine and valproic acid. The lowest values of the luminal area and choroidal vascular index (CVI) were found in patients receiving valproic acid; comparison with matched healthy controls showed statistically significant differences.

CONCLUSION

Valproic acid and carbamazepine are associated with thinning of the p-RNFL in epilepsy patients, but the macular and radial peripapillary VD were not affected.However, a reduction of choroidal vascular blood flow was found in epilepsy patients taking valproic acid.

Choroidal changes in Crimean-Congo hemorrhagic fever

PURPOSE

The goal of this study was to evaluate the effect of Crimean-Congo hemorrhagic fever (CCHF) on choroidal tissue.

METHODS

Thirty-two CCHF patients and 34 healthy individuals were included in this cross-sectional study. All subjects were assessed using spectral domain optical coherence tomography and ImageJ software. The choroidal thickness (CT) in the subfoveal, nasal and temporal regions 1 mm from the foveal center was measured. The total choroidal area (TCA), luminal area (LA), stromal area (SA) and choroidal vascularity index (CVI) were calculated.

RESULTS

The nasal (P=0.002), subfoveal (P=0.006), and temporal CT (P=0.028) were significantly higher in the CCHF group. The TCA (P=0.021), SA (P=0.001) was significantly higher, and LA/SA (P<0.001) and CVI (P<0.001) were significantly lower in patients with CCHF. Significant negative correlations were found between temporal CT (r=-0.387, P=0.029), TCA (r=-0.461, P=0.008), LA (r=-0.480, P=0.005) SA (r=-0.419, P=0.017) and fibrinogen. Nasal CT, temporal CT, TCA and SA tended to increase with the severity of the disease, while LA/SA tended to decrease when CCHF patients were grouped into mild and moderate stages.

CONCLUSIONS

This study demonstrates significant changes in the choroidal structure and vascular characteristics in CCHF patients. These findings may be associated with endothelial damage, vascular leakage, capillary fragility, impaired immune response, and/or inflammation.

COMPARISON OF THE CHOROIDAL VASCULARITY INDEX MEASUREMENTS OF IMAGES ACQUIRED WITH DIFFERENT OPTICAL COHERENCE TOMOGRAPHY SCAN SCALE TYPES

PURPOSE

To evaluate the differences in choroidal vascularity index (CVI) measurements between images acquired at the 1:1 pixel scale and at the 1:1 µ m scale of the Heidelberg optical coherence tomography device.

METHODS

Forty-five healthy eyes of 45 healthy subjects were included for this study. Fovea-centered scans were obtained with an enhanced-depth imaging mode with a high-speed protocol scan. Each scan was exported in 3 different types: 1) 1:1 pixel scale type; 2) 1:1 µ m scale type (MST); and 3) 4×-magnified MST (4×MST; 400%-magnified 1:1 µ m images exported via screenshot). A comparison between CVI measurements based on the different scale types of optical coherence tomography images was conducted using the Bland-Altman analysis and intraclass correlation coefficient.

RESULTS

The image with the worst clarity was acquired via the MST, and the CVI was found to be higher in MST images (69.05 ± 3.21) compared with the other groups. The intraclass correlation coefficient between the CVI values of the 4×MST and pixel scale type images was 0.92, between those of the 4×MST and MST images was 0.33, and between those of the pixel scale type and MST images was 0.44.

CONCLUSION

The optical coherence tomography scale and export method type significantly influence the image resolution, CVI, and choroidal area measurements.

Characteristics of myopic and hyperopic eyes in patients with antimetropia

CLINICAL RELEVANCE

Antimetropia is a rare type of anisometropia in which one eye is myopic and the fellow is hyperopic, This optical condition condition permits the evaluation of both sides of the emmetropisation process failure in the same individual by minimising genetic and environmental factors.

BACKGROUND

This study aimed to evaluate the ocular biometric, retinal, and choroidal characteristics of myopic and hyperopic eyes of antimetropic subjects older than six years.

METHODS

In this retrospective study, myopic and hyperopic eyes of 29 antimetropic patients with a spherical equivalent (SE) difference of at least 2.00D between the eyes were included. Axial length (AL), mean corneal keratometry, anterior chamber depth, the proportion of anterior chamber depth in AL, crystalline lens power, central macular thicknesses, disc-to-fovea distance, fovea-disc angle, peripapillary retinal nerve fibre layer (RNFL) thicknesses, and subfoveal choroidal features were compared between the eyes. The prevalence of amblyopia was determined. Refractive parameters and total astigmatic profile were evaluated in eyes with and without amblyopia.

RESULTS

The median absolute SE and AL differences between the eyes were 3.50D (interquartile range:1.75) and 1.18 mm (interquartile range:0.76), respectively (p < 0.001). Myopic eyes had lower crystalline lens power and proportion of anterior chamber depth in AL, and longer disc-to-fovea distance. Macular thicknesses, global RNFL, and temporal RNFL were thicker in myopic eyes, and there was no difference in other RNFL quadrants. Despite the increase in the choroidal vascularity index, other choroidal parameters were decreased in myopic eyes. Amblyopia was found in three of the myopic eyes and seven of the hyperopic eyes (p = 0.343). The highest interocular SE and AL difference and the highest frequency of anisoastigmatism were observed in patients with amblyopia in the myopic eye.

CONCLUSION

Each ocular structure may respond differently to, or may be affected differently by, ametropic conditions.

Choroidal Changes in Patients with Diabetic Retinopathy: A Retrospective Study

This study aimed to investigate the characteristic choroidal changes in patients with diabetic retinopathy and identify factors affecting choroidal thickness (CTh), choroidal vascular index (CVI), and choriocapillaris flow. We retrospectively analyzed 79 eyes of 48 patients with diabetes between August 2021 and February 2022. We collected laboratory data, including HbA1c, serum creatinine, blood urea nitrogen, triglyceride, total cholesterol, high-density lipoprotein, and low-density lipoprotein (LDL) levels. Optical coherence tomography images of the foveal avascular zone, retinal vascular density, choroidal flow, retinal thickness, CTh, and CVI were analyzed. Possible determining factors affecting CTh, CVI, and choriocapillaris flow were analyzed using nonparametric multivariate analysis. LDL (p < 0.001) positively correlated with CTh, whereas CVI (p = 0.007) was negatively correlated with CTh in diabetic patients with diabetes. We also identified a negative correlation between choriocapillaris flow and deep parafoveal retinal vessel density in patients with low-grade diabetic retinopathy (DR), which diminished in those with more advanced DR. Our study provides further information on the changes in choroidal structure and blood flow in patients with diabetes.

Assessment of choriocapillaris and choroidal vascular changes in posterior uveitis using swept-source wide-field optical coherence tomography angiography

PURPOSE

To evaluate choriocapillaris (CC) and choroidal vascular changes in patients with posterior uveitis using swept-source (SS) wide-field optical coherence tomography angiography (OCTA).

METHOD

Consecutive patients with posterior uveitis were evaluated using 3×3 mm and 12×12 mm OCTA scan patterns and montage images of 5×12×12 mm or 2×15×9 mm, covering approximately 70°-90° of the retina. The images were quantitatively and qualitatively analysed and compared with healthy controls.

RESULTS

Eighty-six eyes of 56 patients with posterior uveitis (mean age 45.2±19.9 years; 58.9% female), and 38 eyes of 19 age-matched healthy controls (57.9% female) were included. The mean perfusion density (PD) in 3×3 mm and 12×12 mm CC scans was significantly lower in eyes with posterior uveitis compared with those of healthy controls. However, no significant difference in the mean PD of choroidal scans was found comparing eyes with posterior uveitis and healthy controls. The mean PD in eyes with active disease was significantly higher compared with the inactive eyes on 12×12 mm choroidal scans (55.61% vs 51.25%, p=0.02), while no difference was found in the CC slabs.

CONCLUSION

CC and choroidal assessment using OCTA provides useful information in patients with posterior uveitis. SS-OCTA metrics of the CC and choroidal slabs are promising tools in uveitis patients in the future.

TRIAL REGISTRATION NUMBER

NCT02811536.

Correlation between choroidal vascularity and retrobulbar ocular blood flow changes and thyroid-associated ophthalmopathy activity: a cross-sectional study

OBJECTIVE

To evaluate the alterations in retrobulbar color Doppler imaging (CDI) parameters and retinal/choroidal optical coherence tomography angiography (OCTA) parameters and their association with the clinical activity and severity in thyroid-associated orbitopathy (TAO) patients.

METHODS

In this study, the retrobulbar flow parameters including resistance index (RI), Pulsatile Index(PI), peak systolic velocity (PSV) and end diastolic velocity (EDV) in posterior ciliary artery (PCA), central retinal artery (CRA) and ophthalmic artery (OA) were determined by CDI. Moreover, the retina and choroidal vascularity including the superficial vessel density (SVD), deep vessel density (DVD), choroidal thickness (ChT) and choroidal vascularity, including total choroidal area (TCA), luminal area (LA), stromal area (SA) and Choroidal Vascularity Index (CVI), were determined by OCTA. All patients grouped as active TAO and inactive TAO based on Clinical activity score (CAS). We picked the severe eye among the subjects and compared all parameters between two groups. We analyzed the correlations among those parameters.

RESULTS

There was a significant difference in CAS score, proptosis value, ChT, LA, CVI between patients with active TAO and inactive TAO. In the active group, PSV and EDV of PCA were significantly higher than the inactive group. On logistic regression analysis, CAS was closely associated with PSV-PCA. On multiple linear regression, proptosis value was closely associated with ChT, LA, SA and CVI.

CONCLUSION

Choroidal vascularization and retrobulbar blood flow were concurrently higher in active TAO patients and several variables in choroid circulation was closely related to TAO clinical features.

Choroidal Morphology and Photoreceptor Activity Are Related and Affected by Myopia Development

Purpose

The choroid is critical for the regulation of eye growth and is involved in the pathogenesis of myopia-associated ocular complications. This study explores the relationship among choroidal biometry, photoreceptor activity, and myopic growth in marmosets (Callithrix jacchus) with lens-induced myopia.

Methods

A total of 34 common marmosets aged 92 to 273 days old were included in this study. Axial myopia was induced in 17 marmosets using negative soft contact lenses and 17 marmosets served as untreated controls. Cycloplegic refraction (RE) and vitreous chamber depth (VCD) were measured using autorefraction and A-scan ultrasonography, respectively. Choroidal scans were obtained using spectral-domain optical coherence tomography and binarized to calculate subfoveal choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), stromal area (SA), choroidal vascularity index (CVI), and LA/SA. To assess photoreceptor activity, the a-wave of the full-field electroretinogram was measured. Regression models were used to investigate the relationship between outcome measures.

Results

Eyes induced with axial myopia (RE = -7.14 ± 4.03 diopters [D], VCD = 6.86 ± 0.39 mm) showed significant reductions (4.92-21.24%) in all choroidal parameters (ChT, TCA, LA, SA, CVI, and LA/SA) compared to controls (RE = -1.25 ± 0.60 D, VCD = 6.58 ± 0.26 mm, all P < 0.05), which changed as a function of refraction and vitreous elongation, and were associated with a decrease in the a-wave amplitude. Further, multiple regression showed that a combination of ChT and CVI could well predict RE and VCD.

Conclusions

This study reports the existence of significant alterations in choroidal morphology in non-human primate eyes induced with myopia. The changes in choroidal anatomy were associated with reduced light-adapted a-wave amplitude. These findings may represent early markers for reduced visual performance and chorioretinal complications known to occur in eyes with large degrees of myopia.

Longitudinal Retinal and Choroidal Image Analysis in a Set of Monozygotic Twins

We analyzed multimodal retinal and choroidal imaging, including optical coherence tomography (OCT) and OCT angiography (OCTA), to assess differences and characterize variations in the retinal and choroidal structure and microvasculature between healthy monozygotic twins without ocular or systemic pathology over a five-year period. Retinal imaging of both subjects revealed normal age-related changes. There was up to an 11% difference in OCT and OCTA variables within the subjects, both at baseline and at five years, and there was up to an 18% difference in OCT and OCTA parameters between the subjects for both time points. Larger changes in subfoveal choroidal thickness and foveal avascular zone area were observed. Our observations suggest that the parafoveal superficial capillary plexus, choroidal vascularity index, central subfield thickness, retinal nerve fiber layer thickness, and ganglion cell-inner plexiform layer thickness may be more heavily influenced by genetic, rather than environmental, factors. In contrast, subfoveal choroidal thickness and the foveal avascular zone area may be more heavily influenced by environmental factors. The environmental impact on retinal and choroidal structure and microvasculature is increasingly important to characterize, as such imaging parameters are being explored as potential biomarkers of systemic disease. These differences, as seen in these identical twin subjects, may be important considerations in supporting the security of biometric identifiers.

CHOROIDAL VASCULARITY AND VISUAL OUTCOMES IN MACULA-OFF RHEGMATOGENOUS RETINAL DETACHMENT

PURPOSE

To investigate the association between visual outcomes and choroidal changes in patients with macula-off rhegmatogenous retinal detachment.

METHODS

This study retrospectively reviewed 63 eyes of patients with macula-off rhegmatogenous retinal detachment who underwent vitrectomy. Their fellow eyes were analyzed as a control group. The choroidal vascularity index (CVI), ellipsoid zone/external limiting membrane integrity, central foveal thickness, and subfoveal choroidal thickness were documented and analyzed. Linear regression analyses were performed to identify factors affecting the final best-corrected visual acuity.

RESULTS

Eyes with rhegmatogenous retinal detachment showed increased CVI (68.8 ± 4.1) compared with the control group (66.1 ± 8.8, P = 0.028). Multivariate linear regression analysis revealed that patients with a poor final best-corrected visual acuity had a longer detachment duration ( P = 0.002), worse baseline best-corrected visual acuity ( P = 0.034), thinner central foveal thickness ( P = 0.005), and greater CVI ( P = 0.001) and were more likely to be tamponated with silicone oil ( P = 0.001). Choroidal vascularity index was particularly increased in eyes with poor ellipsoid zone/external limiting membrane integrity, prolonged detachment duration, thin central foveal thickness, and worse best-corrected visual acuity.

CONCLUSION

Increased CVI could indicate poor visual outcomes in patients with macula-off rhegmatogenous retinal detachment. Choroidal remodeling could be associated with the disruption of the ellipsoid zone/external limiting membrane integrity.

Quantitative analysis of deep learning-based denoising model efficacy on optical coherence tomography images with different noise levels

BACKGROUND

To quantitatively evaluate the effectiveness of the Noise2Noise (N2N) model, a deep learning (DL)-based noise reduction algorithm, on enhanced depth imaging-optical coherence tomography (EDI-OCT) images with different noise levels.

METHODS

The study included 30 subfoveal EDI-OCT images averaged with 100 frames from 30 healthy participants. Artificial Gaussian noise at 25.00, 50.00, and 75.00 standard deviations were added to the averaged (original) images, and the images were grouped as 25N, 50N, and 75N. Afterward, noise-added images were denoised with the N2N model and grouped as 25dN, 50dN, and 75dN, according to previous noise levels. The choroidal vascularity index (CVI) and deep choroidal contrast-to-noise ratio (CNR) were calculated for all images, and noise-added and denoised images were compared with the original images. The structural similarity of the noise-added and denoised images to the original images was assessed by the Multi-Scale Structural Similarity Index (MS-SSI).

RESULTS

The CVI and CNR parameters of the original images (68.08 ± 2.47 %, and 9.71 ± 2.80) did not differ from the only 25dN images (67.97 ± 2.34 % and 8.50 ± 2.43) (p:1.000, and p:0.062, respectively). Noise reduction improved the MS-SSI at each noise level (p < 0.001). However, the highest MS-SSI was achieved in 25dN images.

CONCLUSIONS

The DL-based N2N denoising model can be used effectively for images with low noise levels, but at increasing noise levels, this model may be insufficient to provide both the original structural features of the choroid and structural similarity to the original image.

Insights into the pattern of choroidal vascularity index changes in idiopathic macular hole

This retrospective study aimed to investigate the changes in choroidal vascularity index (CVI) before and after surgery for idiopathic macular hole (MH). Enhanced depth imaging optical coherence tomography (EDI-OCT) images were analyzed at baseline and at 1-week, 1-month, and 3-month postoperative visits. A total of 97 patients (97 eyes) were included in the study. At baseline, overall CVI and macular CVI showed negative correlation with axial length (AL) and positive correlation with central corneal thickness (CCT). There were no significant differences in macular CVI or overall CVI between affected and healthy eyes, as well as in subgroup analysis of different stages of macular CVI. Following surgery, there was a significant decrease in CVI at 1 week postoperatively, followed by a gradual recovery to baseline levels over time. The observed changes in CVI may be attributed to factors such as air tamponade, pressure changes, and photoreceptor metabolism. This study provides insights into the pattern of CVI changes associated with MH surgery. The findings suggest that stage 4 MH is associated with decreased macular CVI in affected eyes. These results contribute to a better understanding of the effects of surgery on choroidal blood flow in MH patients.

Racial Differences in Choroidal Vascularity Index in Healthy Patients: Novel Insights

BACKGROUND AND OBJECTIVE

Choroidal vascularity index (CVI) measures the ratio of blood vessels in the choroid to the total choroidal area. We aimed to compare CVI between young Black and White patients without a history of ocular or systemic disease.

PATIENTS AND METHODS

We used a previously validated algorithm for shadow compensation and choroidal vessel binarization to measure CVI across the Early Treatment of Diabetic Retinopathy Study grid.

RESULTS

Black patients had a lower CVI (ß = -0.05, P < 0.001) compared to White patients. Choroidal volume or luminal volume did not significantly differ with respect to race, whereas there was a trend for Black patients to have a greater stromal volume (ß = 3.08, P = 0.01).

CONCLUSIONS

Black patients have a lower CVI than do White patients, likely due to a greater proportion of stromal volume. Further study of this parameter is warranted to validate the findings of this exploratory study. [Ophthalmic Surg Lasers Imaging Retina 2024;55:30-38.].

Semi-supervised contrast learning-based segmentation of choroidal vessel in optical coherence tomography images

Objective.Choroidal vessels account for 85% of all blood vessels in the eye, and the accurate segmentation of choroidal vessels from optical coherence tomography (OCT) images provides important support for the quantitative analysis of choroid-related diseases and the development of treatment plans. Although deep learning-based methods have great potential for segmentation, these methods rely on large amounts of well-labeled data, and the data collection process is both time-consuming and laborious.Approach.In this paper, we propose a novel asymmetric semi-supervised segmentation framework called SSCR, based on a student-teacher model, to segment choroidal vessels in OCT images. The proposed framework enhances the segmentation results with uncertainty-aware self-integration and transformation consistency techniques. Meanwhile, we designed an asymmetric encoder-decoder network called Pyramid Pooling SegFormer (APP-SFR) for choroidal vascular segmentation. The network combines local attention and global attention information to improve the model's ability to learn complex vascular features. Additionally, we proposed a boundary repair module that enhances boundary confidence by utilizing a repair head to re-predict selected fuzzy points and further refines the segmentation boundary.Main results.We conducted extensive experiments on three different datasets: the ChorVessel dataset with 400 OCT images, the Meibomian Glands (MG) dataset with 400 images, and the U2OS Cell Nucleus Dataset with 200 images. The proposed method achieved an average Dice score of 74.23% on the ChorVessel dataset, which is 2.95% higher than the fully supervised network (U-Net) and outperformed other comparison methods. In both the MG dataset and the U2OS cell nucleus dataset, our proposed SSCR method achieved average Dice scores of 80.10% and 87.26%, respectively.Significance.The experimental results show that our proposed methods achieve better segmentation accuracy than other state-of-the-art methods. The method is designed to help clinicians make rapid diagnoses of ophthalmic diseases and has potential for clinical application.

Characteristics of the retina and choroid in fibromyalgia patients and their correlation with disease severity and quality of life

BACKGROUND

To evaluate retinal and choroidal characteristics of fibromyalgia (FM) patients using spectral-domain optical coherence tomography (SD-OCT), to compare them with healthy controls, and to determine the correlation of these measurements with disease severity and quality of life.

METHODS

Thirty-nine eyes of 39 patients with FM and 44 eyes of 44 age- and sex-matched healthy subjects were enrolled. The retinal nerve fiber layer (RNFL), central macular thickness (CMT), and choroidal thickness (CT) measurements of the subjects were obtained using SD-OCT (Maestro, Topcon Co. Tokyo, Japan), choroidal vascular index (CVI) was calculated by using the binarization method and the results were compared. Disease duration (DD), widespread pain index (WPI), symptom severity scale (SSS), visual analog scale (VAS), ocular pain assessment survey (OPAS), FM impact questionnaire (FIQ), European Quality of Life-5 Dimensions-3 level (EQ-5D-3 L), European Quality VAS score (EQ-VAS) and use of pregabalin were recorded. Correlations between the SD-OCT results and the FM parameters were evaluated.

RESULTS

No significant difference was found in terms of age and gender (p = 0.612, p = 0.244 respectively). Patients in the FM group had significantly thinner RNFL superior quadrant and CT (p = 0,009 and p < 0.001, respectively). CVI was significantly higher in the FM group (p < 0.001). There was an inverse correlation between OPAS and CT (r = -0.379, p = 0.027) and between VAS and CVI (r = -0.398, p = 0.020). The use of pregabalin had no effect on SD-OCT (p > 0.05).

CONCLUSION

Patients with FM demonstrated reduced RNFL superior quadrant and CT and increased CVI. Ocular and general body pain in FM was found to be associated with SD-OCT.

Retinal and choroidal microvasculature in early and three months post COVID-19: A case-control study

To compare the retinal vascular density (VD), choroidal vascularity index (CVI), and choroidal thickness (CHT) between patients infected with COVID-19 and healthy subjects using non-invasive optical coherence tomography angiography (OCTA) and enhanced depth imaging OCT (EDI-OCT) technique. This case-control study was carried out on patients with COVID-19 and healthy controls. Patients' data were acquired immediately after active infection and three months later. The diagnosis was based on clinical symptoms and a positive PCR test. VDs in superficial and deep capillary plexuses (SCP and DCP) and CHT and CVI were measured and compared between groups. A total of 160 eyes from 80 patients (55% female, mean age 51 ± 13 years) and 80 controls (55% female, mean age 49 ± 12 years) were enrolled. In acute phase infection, the mean foveal avascular zone (FAZ) area was 0.28 ± 0.06 mm2 and 0.22 ± 0.05 mm2 in patient and control groups, respectively (P < 0.001). CVI was 61.06 ± 2.59 µm and 72.28 ± 3.84 µm in patients and control groups, respectively (P < 0.001). After three months, the mean FAZ area was 0.28 ± 0.06 mm2 and 0.23 ± 0.05 mm2 in the patient and control groups, respectively (P < 0.001). CVI was 60.93 ± 2.11 µm and 72.46 ± 3.80 µm in patients and control groups, respectively (P < 0.001). Subfoveal CHT was not significantly different between groups (P = 0.69). SCP and DCP VDs were significantly less in the patients' group (P < 0.001). In the patients' group, the VDs in the DCP of the whole images and parafoveal DCP (P < 0.001) were reduced significantly after three months in comparison to the acute phase, while the FAZ area, subfoveal CHT, and CVI were not significantly different. COVID-19 infection may be associated with acute and long-term changes of VDs in the retinal and choroidal vasculature without significant effect on the subfoveal CHT.

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.

Longitudinal Analysis of Retinal Microvascular and Choroidal Imaging Parameters in Parkinson's Disease Compared with Controls

Purpose

To quantify rate of change of retinal microvascular and choroidal structural parameters in subjects with Parkinson's disease (PD) compared with controls using OCT and OCT angiography (OCTA).

Design

Prospective longitudinal study.

Participants

Seventy-four eyes of 40 participants with PD and 149 eyes of 78 control individuals from the Eye Multimodal Imaging in Neurodegenerative Disease database.

Methods

Subjects underwent OCT and OCTA imaging at 2 time points approximately 12 months apart.

Main Outcome Measures

Imaging parameters included central subfield thickness, ganglion cell-inner plexiform layer (GC-IPL) thickness, peripapillary retinal nerve fiber layer thickness, choroidal vascularity index, superficial capillary plexus perfusion density (PFD), vessel density (VD), and foveal avascular zone area.

Results

Participants with PD had greater rate of yearly decrease in GC-IPL (PD = -0.403μm, control = + 0.128 μm; P = 0.01), greater yearly decline in PFD in the 3 × 3 mm ETDRS circle (PD = -0.016, control = + 0.002; P < 0.001) and ring (PD = -0.016, control = + 0.002; P < 0.001); 6 × 6 mm ETDRS circle (PD = -0.021, control = 0.00; P = 0.001), and outer ring (PD = -0.022, control = 0.00; P = 0.001). Participants with PD had greater rate of yearly decline in VD in 3 × 3 mm circle (PD = -0.939/mm, control = + 0.006/mm; P < 0.001) and ring (PD = -0.942/mm, control = + 0.013/mm; P < 0.001); 6 × 6 mm circle (PD = -0.72/mm, control = -0.054/mm; P = 0.006), and outer ring (PD = -0.746/mm, control = -0.054/mm; P = 0.005). When stratified by PD severity based on Hoehn and Yahr stage, faster rates of decline were seen in Hoehn and Yahr stages 3 to 4 in the 3 × 3 mm circle PFD and VD as well as 3 × 3 mm ring VD.

Conclusions

Individuals with PD experience more rapid loss of retinal microvasculature quantified on OCTA and more rapid thinning of the GC-IPL than controls. There may be more rapid loss in patients with greater disease severity.

Financial Disclosures

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Evaluation of peripapillary choroidal vascularity index in young smokers

Purpose: This retrospective study aimed to compare the peripapillary choroidal vascularity index (CVI) between young smokers who smoked less than 5 packs/year and non-smokers.Methods: The study included 52 smokers and 67 non-smokers, and comprehensive eye examinations were performed on all participants. Axial lengths (AL) were measured, and peripapillary enhanced depth imaging optical coherence tomography (EDI-OCT) images were obtained and evaluated using the Open Source ImageJ software. The CVI, total choroidal area (TCA), luminal area (LA), stromal area (SA), and retinal nerve fibre layer (RNFL) quadrants were compared between the two groups.Results: The mean age of the smokers was 23.76 ± 1.84 years, and for non-smokers, it was 23.98 ± 2.18 years. The mean peripapillary CVI for smokers was 0.65 ± 0.08, and for non-smokers, it was 0.67 ± 0.03. No statistically significant difference in CVI was observed between the two groups. However, statistically significant differences were found in the temporal inferior (TI), temporal superior (TS), nasal inferior (NI), and nasal superior (NS) quadrants of the RNFL between the two groups (p < 0.05). There was no correlation between the number of packs/year and CVI values in the smoking group (r = 0.031, p = 0.826).Conclusion: The study revealed no significant difference in CVI among young smokers who smoked less than 5 packs/year compared to non-smokers. However, there was a statistically significant decrease in the TI, TS, NI, and NS quadrants of the RNFL in early-age smokers.

Choroidal vascular changes in silicone oil-filled eyes after vitrectomy for rhegmatogenous retinal detachments

INTRODUCTION

The tamponade of silicone oil (SO) can affect both the structure and blood flow of the retina. However, there are few studies on the effect of SO tamponade on choroidal blood flow. Our study aimed to compare the effects of SO tamponade on the choroidal vascular index (CVI) and choroidal thickness (CT) in patients with unilateral rhegmatogenous retinal detachment (RRD) with operated eyes and fellow healthy eyes.

METHODS

We retrospectively collected demographic and clinical data from 36 patients who underwent 23G pars plana vitrectomy and SO tamponade for unilateral complicated RRD. Enhanced depth imaging-optical coherence tomography (EDI-OCT) scans were performed both within 1 week before SO removal and at the last follow-up visit after SO removal. Using ImageJ software, images were binarized to segment the total choroidal area, luminal area, and stromal area, respectively. The CVI was calculated as CVI=(luminal area)/(total choroidal area), and CT was also evaluated.

RESULTS

During SO tamponade, the CVI and luminal area in operated eyes were significantly lower compared to fellow eyes (57.616 ± 0.030 vs. 60.042 ± 0.019, P < 0.0001; 0.909 [0.694; 1.185] vs. 1.091 [0.785; 1.296], P = 0.007). Even after SO removal, the CVI remained lower in operated eyes than in fellow eyes (59.530 ± 0.018 vs. 60.319 ± 0.020, P = 0.031). Both CVI and luminal area were lower in operated eyes before SO removal than after SO removal (57.616 ± 0.030 vs. 59.530 ± 0.018, P = 0.0003; 0.909 [0.694; 1.185] vs. 0.994 [0.712; 1.348], P = 0.028). The duration of SO tamponade was positively correlated with the difference in CVI between fellow eyes and operated eyes during SO tamponade (P = 0.035). Total choroidal area, stromal area, and CT did not differ significantly between fellow eyes and operated eyes or between pre- and post-SO removal.

CONCLUSIONS

SO tamponade reduces CVI and decreases choroidal blood circulation in patients with retinal detachments required vitrectomy combined with SO tamponade. The longer the SO tamponade time, the more CVI reduction. In future work, we will aim to reduce these side effects by shortening the duration of silicone oil filling.

Comparison of the Choroid in Primary Open Angle and Angle Closure Glaucoma Using Optical Coherence Tomography

PRCIS

The current study highlights distinct choroidal alterations in primary open angle (POAG) and primary angle closure (PACG) glaucomas, underscoring the potential of the Choroidal Vascularity Index (CVI) as a valuable indicator for understanding glaucoma pathogenesis.

PURPOSE

To evaluate choroidal structural changes in patients with POAG and PACG and healthy controls utilizing the CVI and subfoveal choroidal thickness by enhanced depth imaging optical coherence tomography.

METHODS

This study was cross-sectional. A total of 171 eyes of 171 subjects, comprising 69 eyes with untreated POAG, 58 eyes with untreated PACG, and 44 healthy eyes, were enrolled in this study. Subfoveal choroidal thickness, luminal area (LA), stromal area (SA), and total choroidal area were measured on enhanced depth imaging-optical coherence tomography scans. The CVI parameter is calculated as the proportion of LA to the total choroidal area.

RESULTS

This study included 69 patients with POAG with a mean age of 51.4 ± 13.3 years, 58 patients with PACG with a mean age of 57.0 ± 7.3 years, and 44 healthy subjects with a mean age of 51.11 ± 10.7 years. The CVI in the POAG and PACG groups was significantly lower than that in the control group ( P = 0.001 and P = 0.005, respectively); however, not significantly different between the two glaucoma groups ( P = 1.000). POAG eyes had significantly lower LA than PACG and controls ( P = 0.014 and P = 0.049, respectively), whereas PACG eyes had significantly greater SA than controls ( P = 0.041).

CONCLUSIONS

The CVI of POAG and PACG eyes was significantly lower than that of normal eyes. A reduced LA was observed mainly in eyes with POAG, and an increased SA was observed mainly in eyes with PACG. The role of the choroid may differ between POAG and PACG eyes.

Choroidal Vascular Index in Patients With Attention-Deficit/Hyperactivity Disorder and Methylphenidate

PURPOSE

To investigate choroidal vascularity in children with attention-deficit/hyperactivity disorder (ADHD) who were not receiving therapy, children with ADHD who were regularly taking methylphenidate (MPH), and healthy controls.

METHODS

The study included three groups: patients with newly diagnosed ADHD without treatment, patients diagnosed as having ADHD who were already being treated with oral MPH, and controls. Both choroidal vascularity index (CVI) and choroidal thickness were measured using an enhanced-depth imaging mode of spectral-domain optical coherence tomography (EDIOCT) (Spectralis; Heidelberg Engineering GmbH).

RESULTS

There was a significant difference in CVI and stromal area between groups. Post-hoc univariate analysis showed that CVI was significantly lower in patients with ADHD treated with MPH compared with the other groups (P < .001, for each); however, there was no difference between the treatment-free ADHD group and controls (P = .305). In contrast, stromal area was significantly higher in patients with ADHD treated with MPH than the other groups (P < .001, for each group). The correlation of CVI with MPH treatment duration in patients with ADHD treated with MPH showed a significant, moderate negative correlation (P = .01, r = - 0.66).

CONCLUSIONS

CVI is reduced in patients with ADHD treated with MPH, and the decrease in CVI becomes significant with increasing duration of MPH treatment. This result reflects an indirect effect of MPH treatment on choroidal vascular structures. [J Pediatr Ophthalmol Strabismus. 2023;60(6):411-416.].