Optical Coherence Tomography Angiography in Intermediate Uveitis

Polyvinylpyrrolidone-curcumin nanoparticles with immune regulatory and metabolism regulatory effects for the treatment of experimental autoimmune uveitis

Uveitis comprises a cluster of intraocular inflammatory disorders characterized by uncontrolled autoimmune responses and excessive oxidative stress leading to vision loss worldwide. In the present study, curcumin (CUR) was conjugated with polyvinylpyrrolidone (PVP) to form PVP-CUR nanoparticles with significantly elevated solubility and outstanding multiple radical scavenging abilities. In vitro studies revealed that PVP-CUR nanoparticles markedly mitigated oxidative stress and reduced apoptosis in a H2O2-induced human retinal pigment epithelial cell line (ARPE-19) and promoted phenotypic polarization from M1 to M2 in an LPS-induced human microglial cell line (HMC3). Further in vivo studies demonstrated the prominent therapeutic effects of PVP-CUR nanoparticles on experimental autoimmune uveitis (EAU), which relieved clinical and pathological progression, improved perfusion and tomographic manifestations of retinal vessels, and reduced blood-retinal barrier (BRB) leakage; these effects may be mediated by mitigating oxidative stress and attenuating macrophage/microglia-elicited inflammation. Notably, treatment with PVP-CUR nanoparticles was shown to regulate metabolite alterations in EAU rats, providing novel insights into the underlying mechanisms involved. Additionally, the PVP-CUR nanoparticles showed great biocompatibility in vivo. In summary, our study revealed that PVP-CUR nanoparticles may serve as effective and safe nanodrugs for treating uveitis and other oxidative stress- and inflammation-related diseases.

Skeleton density and ellipsoid zone loss are prognostic for progression in Macular Telangiectasia Type 2

Macular Telangiectasia Type 2 (MacTel) is a chronic, progressive disease of the central retina characterized by vascular and neurodegenerative changes. As there is currently no treatment for non-neovascular MacTel, there is a dearth for biomarkers identifying eyes with an increased risk for disease progression for patient counseling and clinical trial recruitment. Eyes were classified to be stable or progressive, defined by the fundus photography-based grading system by Gass and Blodi. First, structural differences between these two groups were assessed, employing optical coherence tomography (OCT) and OCT-angiography. Univariate regression analyses revealed evidence towards a lower superficial retinal layer (SRL) vessel density (VD), skeleton density (SD) and deep retinal layer (DRL) SD in progressing compared to stable eyes (p = 0.05, p = 0.05, p = 0.07). Second, a multivariable predictive model was employed to examine the predictive value of structural and functional parameters for disease progression. Baseline best corrected visual acuity (BCVA) and SRL SD are prognostic for disease progression (p < 0.001, p = 0.05). The presence of ellipsoid zone (EZ) loss is prognostic for future central retinal thickness (p < 0.01). We propose SRL SD, BCVA, and EZ loss as prognostic biomarkers and as possible outcome measures in future interventional studies in MacTel.

Evaluation of Optical Coherence Tomography Angiography Findings in Pars Planitis and Multiple Sclerosis Associated Intermediate Uveitis in Remission

PURPOSE

To evaluate the microvasculature during remission in patients with pars planitis (PP-IU) and multiple sclerosis-associated intermediate uveitis (MS-IU) using optical coherence tomography angiography (OCT-A).

METHODS

Single-center, descriptive, case-control study was conducted. Adult patients (≥16 years) with IU in remission (PP-IU and MS-IU) and healthy age-sex matched healthy controls (HC) were enrolled to the study. Demographic/clinical features, best-corrected visual acuity (BCVA), ocular findings, neurological symptoms and preferred treatments were recorded. The presence of cystoid macular edema (CME) during follow-up was recorded. All IU patients in remission and HC subjects were scanned with OCT-A. Foveal avascular zone (FAZ) areas of superficial and deep capillary plexus (SCP/DCP) and vascular densities of SCP, DCP and choriocapillaris were obtained from OCT-A and compared between the groups.

RESULTS

Sixty-nine eyes of 37 IU patients in remission and 20 HC were included (44 eyes/23 patients in PP-IU, 25/14 in MS-IU, 40/20 in HC). No statistically significant differences were observed in terms of demographic or clinical characteristics of the patients. The vascular density in the SCP was significantly reduced in the PP-IU and MS-IU groups compared to the HC group (p < .05). Nevertheless, there were no significant changes in any of the OCTA parameters between the IU groups. Uveitis duration was found to be correlated with enlargement of the FAZ area in PP-IU (p = .039).

CONCLUSION

OCTA may not be useful in differentiating between PP-IU and MS-IU. Nevertheless, the primary implication in SCP potentially elucidates the pathogenesis of these two subtypes of IU, which are characterized by a shared pathogenesis. The monitoring of the FAZ area in the PP-IU group is valuable in terms of chronicity.

Vessel density on optical coherence tomography angiography is prognostic for future disease course in intermediate uveitis

As most rare diseases, intermediate uveitis lacks reliable endpoints necessary for randomized clinical trials. Therefore, we investigated longitudinal changes of retinal and choriocapillaris perfusion on optical coherence tomography angiography (OCT-A) in intermediate uveitis and their prognostic value for future best corrected visual acuity (BCVA) and central retinal thickness (CRT). In this retrospective, longitudinal cohort study eyes of patients with intermediate uveitis were imaged by swept-source OCT-A (macula-centered 3 × 3 mm; PLEX Elite 9000, Zeiss) and stratified into clinically stable, worsened and improved based on changes in clinical parameters. Superficial (SRL) and deep retinal layers (DRL) were automatically analyzed for vessel density (VD) and choriocapillaris layer for non-perfused area (CCNPA) using ImageJ. Mixed-effects regression analysis controlling for age, sex, and OCT-A signal strength index (SSI) was used to evaluate the prognostic value of OCT-A parameters. 91 eyes (62 stable, 12 worsened, and 17 improved) were included in the analysis and mean follow-up time was 296 days. Longitudinal changes of VD were different between all three groups (p = 0.002 for SRL and p = 0.017 for DRL). Clinically worsened eyes showed a decrease in VD (- 0.032 ± 0.055 for SRL and - 0.027 ± 0.025 for DRL), whereas clinically improved eyes showed an increase in VD (0.037 ± 0.039 for SRL and 0.001 ± 0.023 for DRL). No difference was found for CCNPA. When controlling for age, sex, and SSI, observed differences held true in clinically worsened eyes for DRL (p = 0.011) and in clinically improved eyes for SRL (p = 0.002). An increase of CCNPA in clinically worsened eyes (p = 0.03) compared to clinically stable and improved eyes was evident. Predictive analysis revealed an association of VD in SRL and DRL at baseline with BCVA at follow-up (p = 0.039 and p = 0.047, respectively) and of VD in SRL at baseline with CRT at follow-up (p = 0.046). Alterations in retinal perfusion on OCT-A in intermediate uveitis are partly reversible and OCT-A VD may serve to predict future BCVA and CRT. Thus, perfusion parameters on OCT-A might aid monitoring and serve as prognostic imaging-biomarker.

Associations between retinal microvascular flow, geometry, and progression of diabetic retinopathy in type 2 diabetes: a 2-year longitudinal study

PURPOSE

To determine the association between retinal blood vessel flow and geometric parameters and the risk of diabetic retinopathy (DR) progression through a 2-year prospective cohort study.

METHODS

Patients with type 2 diabetes mellitus (T2DM) were recruited from a diabetic registry between November 2017 and March 2019. All participants underwent standardized examinations at the baseline and 2-year follow-up visit, and the presence and severity of DR were assessed based on standard seven-field color fundus photographs. They also underwent swept-source optical coherence tomography angiography (OCTA) imaging to obtain measurements of foveal avascular zone area, blood vessel density (VD), fractal dimension (FD), blood vessel tortuosity (BVT) in the superficial capillary plexus (SCP) and deep capillary plexus (DCP).

RESULTS

A total of 233 eyes of 125 patients were included, and 40 eyes (17.17%) experienced DR progression within 2 years. DR progression was significantly associated with lower baseline VD (odds ratio [OR] 2.323 per SD decrease; 95% confidence interval [CI] 1.456-3.708; P < 0.001), lower FD (OR, 2.484 per SD decrease; 95% CI 1.268-4.867; P = 0.008), and higher BVT (OR, 2.076 per SD increase; 95% CI 1.382-3.121; P < 0.001) of the DCP after adjusting for confounding factors. The addition of OCTA metrics improved the predictive ability of the original model for DR progression (area under the curve [AUC] from 0.725 to 0.805; P = 0.022).

CONCLUSIONS

OCTA-derived VD, FD and BVT in the DCP were independent predictors of DR progression and showed additive value when added to established risk models predicting DR progression.

Pediatric Pars Planitis: A Review

PURPOSE

To provide an overview of pediatric pars planitis.

METHODS

Narrative literature review.

RESULTS

Pars planitis refers to the idiopathic subset of intermediate uveitis in which there is vitritis along with snowball or snowbank formation occurring in the absence of an associated infection or systemic disease. It is thought to be a T-cell mediated disease with a genetic predisposition. Pars planitis accounts for 5-26.7% of pediatric uveitis cases. Presentation is commonly bilateral but asymmetric, often with insidious onset of floaters and blurred vision. Although pars planitis is known to be a benign form of uveitis in most cases, severe complications secondary to chronic inflammation may arise, with cystoid macular edema being the most common cause of visual morbidity. Mild vitritis in the absence of symptoms, vision loss, or macular edema may be observed. Patients with severe vitritis and/or associated vision-threatening complications require prompt aggressive treatment. A stepladder approach including corticosteroids, immunosuppressive agents, anti‑tumor necrosis factor‑alpha and pars plana vitrectomy and/or laser photocoagulation is the most commonly used method for treatment of pars planitis.

CONCLUSION

Timely diagnosis and adequate treatment of pediatric pars planitis and associated complications are crucial in order to improve visual outcomes.

Application of ImageJ in Optical Coherence Tomography Angiography (OCT-A): A Literature Review

Background

This study aimed to review the literature on the application of ImageJ in optical coherence tomography angiography (OCT-A) images.

Methods

A general search was performed in PubMed, Google Scholar, and Scopus databases. The authors evaluated each of the selected articles in order to assess the implementation of ImageJ in OCT-A images.

Results

ImageJ can aid in reducing artifacts, enhancing image quality to increase the accuracy of the process and analysis, processing and analyzing images, generating comparable parameters such as the parameters that assess perfusion of the layers (vessel density (VD), skeletonized density (SD), and vessel length density (VLD)) and the parameters that evaluate the structure of the layers (fractal dimension (FD), vessel density index (VDI), and lacunarity (LAC)), and the foveal avascular zone (FAZ) that are used widely in the retinal and choroidal studies), and establishing diagnostic criteria. It can help to save time when the dataset is huge with numerous plugins and options for image processing and analysis with reliable results. Diverse studies implemented distinct binarization and thresholding techniques, resulting in disparate outcomes and incomparable parameters. Uniformity in methodology is required to acquire comparable data from studies employing diverse processing and analysis techniques that yield varied outcomes.

Conclusion

Researchers and professionals might benefit from using ImageJ because of how quickly and correctly it processes and analyzes images. It is highly adaptable and potent software, allowing users to evaluate images in a variety of ways. There exists a diverse range of methodologies for analyzing OCTA images through the utilization of ImageJ. However, it is imperative to establish a standardized strategy to ensure the reliability and consistency of the method for research purposes.

Quantitative Analysis of the Choroidal Vascularity in Eyes with Uveitis Using Optical Coherence Tomography Angiography: A Systematic Review

PURPOSE

The purpose of this systematic review is to identify techniques used for quantification of choriocapillaris (CC) flow in eyes with uveitis using optical coherence tomography angiography (OCTA), report reliability and level of correlation with techniques such as indocyanine green angiography (ICGA).

METHODS

A systematic search of several databases was done. The studies were analyzed for techniques of measurement, reliability, and correlation with other modalities. Risk of bias assessment was performed.

RESULTS

Thirteen studies were included. CC vessel density (7 studies) and flow deficit area (4 studies) were the most used indices. There was significant heterogeneity in the studies due to differences in the scan protocol, thresholding strategy, and analysis. Comparison with ICGA was performed by only one study, and reliability indices were reported by only two studies.

CONCLUSION

OCTA is a useful tool to measure the CC vascularity in eyes with uveitis. However, standardized acquisition and analysis protocols are needed.

Experts Opinion: OCTA vs. FFA/ICG in Uveitis - Which Will Survive?

Will optical coherence tomography angiography (OCTA) replace invasive imaging techniques like fundus fluorescein angiography (FFA) and indocyanine green (ICG) angiography entirely? While OCTA is being increasingly applied in the field of medical retina, will we see this change in the subspeciality of uveitis? In this article, five uveitis specialists with renowned imaging expertise answer to 10 specific questions to address this issue. The final verdict based on the comments of the experts suggests that FFA and ICG cannot be replaced by OCTA in uveitis, at least for now. While OCTA can offer new insights into the pathogenesis of certain inflammatory conditions and help in the diagnosis of complications like inflammatory choroidal neovascularisation, multimodal imaging is still the preferred approach in the assessment of patients with uveitis.

Modifications in ocular microperfusion after transcatheter aortic valve implantation

Cerebral embolization is a known complication of transcatheter aortic valve implantation (TAVI) but the effect of the procedure on the ocular perfusion is currently unclear. Thus, we investigated post-procedural morphologic and perfusion changes of the retina and choroid, using optical coherence tomography angiography (OCTA) and color fundus photography (CFP) in a prospective cohort study. Ophthalmic examinations were conducted pre- and post-TAVI. OCTA images were analyzed quantitatively based on vessel density and skeleton density of the superficial and deep retinal plexus as well as the signal intensity and flow deficits in the choriocapillaris. CFP images were assessed for presence of acute retinal ischemia, optic nerve swelling, vessel emboli, hemorrhages and cotton wool spots. Data was analyzed using linear mixed models. Twenty patients (9 women; 11 men) at a mean age of 81 ± 6 years were included. Pre- and post-interventional ocular imaging data were available for 32 eyes. The analysis revealed a significant impairment of the choriocapillaris perfusion after TAVI with an increased proportion of flow deficits (p = 0.044). When controlling for blood pressure, the average size of choriocapillaris flow voids was significantly increased (systolic and diastolic, p = 0.039 and 0.029). Qualitatively, focal areas of retinal ischemia were detected on OCTA in 33% of participants. Silent emboli or cotton wool spots were identified on CFP in 21%. Our findings indicate a reduced choroidal perfusion as well as areas of retinal ischemia and embolization in a considerable proportion of patients following TAVI. Pending confirmation in a larger sample, these complications merit monitoring as well as inclusion in consent procedures for TAVI.

Comparison of Automated Thresholding Algorithms in Optical Coherence Tomography Angiography Image Analysis

(1) Background: Calculation of vessel density in optical coherence tomography angiography (OCTA) images with thresholding algorithms varies in clinical routine. The ability to discriminate healthy from diseased eyes based on perfusion of the posterior pole is critical and may depend on the algorithm applied. This study assessed comparability, reliability, and ability in the discrimination of commonly used automated thresholding algorithms. (2) Methods: Vessel density in full retina and choriocapillaris slabs were calculated with five previously published automated thresholding algorithms (Default, Huang, ISODATA, Mean, and Otsu) for healthy and diseased eyes. The algorithms were investigated with LD-F2-analysis for intra-algorithm reliability, agreement, and the ability to discriminate between physiological and pathological conditions. (3) Results: LD-F2-analyses revealed significant differences in estimated vessel densities for the algorithms (p < 0.001). For full retina and choriocapillaris slabs, intra-algorithm values range from excellent to poor, depending on the applied algorithm; the inter-algorithm agreement was low. Discrimination was good for the full retina slabs, but poor when applied to the choriocapillaris slabs. The Mean algorithm demonstrated an overall good performance. (4) Conclusions: Automated threshold algorithms are not interchangeable. The ability for discrimination depends on the analyzed layer. Concerning the full retina slab, all of the five evaluated automated algorithms had an overall good ability for discrimination. When analyzing the choriocapillaris, it might be useful to consider another algorithm.

A Period of Macular Hyperemia and Subclinical Edema Caused by Phacoemulsification Surgery in Noninfectious Uveitis

PURPOSE

To identify the changes in macular microvasculature in uveitic patients following phacoemulsification.

METHODS

A prospective cohort study was conducted by enrolling uveitic patients who underwent phacoemulsification at the Eye Hospital. Macular vessel densities (VD) of superficial and deep capillary plexus (SCP and DCP) and retinal thickness (RT) were quantified by optical coherence tomographic angiography (OCTA).

RESULTS

Twenty-one eyes obtained satisfactory OCTA scans at all the follow-up visits. After surgery, an increasing trend in SCP VD was found (p = .037) and reached its maximum (+2.79 ± 4.86%) at post-3 months (M). RT increased synchronously. The increases in SCP VD at post-3 M were significantly correlated with the changes in anterior chamber cells (ACCs) at post-1 M and 2 M (r = 0.450, p = .041; r = 0.477, p = .029, respectively).

CONCLUSIONS

Inflammation generates a long-term effect on retina demonstrated as an increase in SCP VD and RT which are associated with synchronous ACCs changes after phacoemulsification.

Intermediate Uveitis: A Review

PURPOSE

This review aims to provide an update on the clinical presentation, etiologies, complications, and treatment options in intermediate uveitis (IU).

METHODS

Narrative literature review.

RESULTS

IU affects all age groups with no clear gender predominance and has varied etiologies including systemic illnesses and infectious diseases, or pars planitis. In some instances, IU may be the sole presentation of an underlying associated condition or disease. Management of IU and its complications include administration of corticosteroids, antimetabolites, T-cell inhibitors, and/or biologics, along with surgical interventions, with varying degrees of effectiveness across literature. In particular, increasing evidence of the safety and efficacy of immunomodulatory agents and biologics has seen greater adoption of these therapies in clinical practice.

CONCLUSIONS

IU is an anatomical description of uveitis, involving intraocular inflammation of the vitreous, peripheral retinal vasculature, and pars plana. Various treatment options for intermediate uveitis are currently used in practice.

Optic coherence tomography angiography findings in fuchs heterochromic iridocyclitis

PURPOSE

To evaluate macular capillary perfusion in patients with fuchs heterochromic iridocyclitis (FHI) by using optical coherence tomography angiography (OCTA).

MATERIAL AND METHOD

A total of 19 eyes of 19 patients with unilateral FHI underwent detailed eye examination. OCTA (RTVue-XR Avanti) images were obtained from both eyes. OCTA parameters, including foveal avascular zone, superficial capillary plexus and deep capillary plexus vessel densities, were compared between the involved and fellow control eyes.

RESULTS

The median age of the patients (11 females, 8 males) was 42.0 ± 9.63 (range 24-57) years. DCP and SCP densities at the parafoveal and perifoveal area were significantly lower in the FHI eyes compared to the control eyes (44.80 ± 5.24% vs. 54.70 ± 3.76% and 43.30 ± 5.10% vs. 53.70 ± 2.73%, respectively; p < 0.05). The median FAZ was 0.29 ± 0.12 (0.11-0.42) mm² in the FHI eyes and 0.26 ± 0.09 (0.10-0.40) mm² in the control eyes. This difference did not reach statistical significance (p = 0.199).

CONCLUSION

Macular capillary perfusion was significantly reduced in both SCP and DCP in the eyes with FHI. FHI, which is known to affect the choroid layer, could also compromise macular capillary perfusion of the retina.

Abnormalities of Retinal Structure and Microvasculature are Associated with Cerebral White Matter Hyperintensities

PURPOSE

While retinal microvasculature represents cerebral small vessels, the retinal nerve fiber layer is the extended white matter of the brain. We aimed to investigate the correlation between changes in retina and white matter hyperintensities (WMH).

METHODS

64 candidates with WMH received the optical coherence tomography angiography (OCTA) examination. WMH were divided into mild or moderate/severe groups according to the Fazekas score. After imaging superficial capillary plexus (SCP) and deep capillary plexus (DCP), we revealed the microvascular density parameters (vascular perfusion density (VPD), vascular length density (VLD), and fovea avascular zone area (FAZ-A)) and morphological parameters (vessel diameter index (VDI), fractal dimension (FD), and vessel tortuosity (VT)). The software algorithm measured the thickness of the peripapillary retina nerve fiber layer (PRNFL).

RESULTS

32 were classified as having mild WMH and 32 were moderate/severe. The Median (interquartile range) ages of the two groups were 58 (54-64) and 61 (57-67) years, respectively. A decrease of FD, VPD and VLD in either SCP or DCP appeared with an increased risk of moderate/severe WMH. Although changes of capillary plexus were not associated with PWMH, decreased FD, VPD, VLD and FAZ-A in either SCP or DCP was associated with an increased risk of moderate/severe DWMH. Participants with moderate/severe WMH demonstrated reduced PRNFL thickness, particularly in the DWMH, compared with mild WMH.

CONCLUSIONS

Abnormalities of retinal microvascular density, morphological parameters, and PRNFL thickness are correlated with the incidence of moderate/severe WMH, particularly the DWMH, suggesting that arteriosclerosis and hypoperfusion are the causes of DWMH.

Artificial Intelligence and Imaging Processing in Optical Coherence Tomography and Digital Images in Uveitis

INTRODUCTION

Computer vision, understood as the area of science that trains computers to interpret digital images through both artificial intelligence (AI) and classical algorithms, has significantly advanced the analysis and interpretation of optical coherence tomography (OCT) in retina research. The aim of this review is to summarise the recent advances of computer vision in imaging processing in uveitis, with a particular focus in optical coherence tomography images.

MATERIAL AND METHODS

Literature review.

RESULTS

The development of computer vision to assist uveitis diagnosis and prognosis is still undergoing, but important efforts have been made in the field.

CONCLUSION

The automatising of image processing in uveitis could be fundamental to establish objective and standardised outcomes for future clinical trials. In addition, it could help to better understand the disease and its progression.

Changes of the retinal and choroidal vasculature in cerebral small vessel disease

Cerebral small vessel disease (CSVD) is associated with changes in the retinal vasculature which can be assessed non-invasively with much higher resolution than the cerebral vasculature. To detect changes at a microvascular level, we used optical coherence tomography angiography which resolves retinal and choroidal vasculature. Participants with CSVD and controls were included. White matter lesions were determined on magnetic resonance imaging (MRI). The retinal and choroidal vasculature were quantified using swept-source optical coherence tomography angiography. Data were analysed using linear regression. We included 30 participants (18 females; patients, n = 20; controls, n = 10) with a mean age of 61 ± 10 years. Patients had a higher mean white matter lesion index and number of lesions than controls (p ≤ 0.002). The intraindividual deviation of choriocapillaris reflectivity differed significantly between age-matched patients (0.234 ± 0.012) and controls (0.247 ± 0.011; p = 0.029). Skeleton density of the deep retinal capillaries was significantly associated with the number of lesions on MRI (β = − 5.3 × 10⁸, 95%-confidence interval [− 10.3 × 10⁸; − 0.2 × 10⁸]) when controlling for age. The choroidal microvasculature and the deep retinal vascular plexus, as quantified by optical coherence tomography angiography, are significantly altered in CSVD. The value of these findings in diagnosing or monitoring CSVD need to be assessed in future studies.

Visual outcomes and choroidal thickness associated with human leukocyte antigen DRB1*04 in unclassifiable uveitis in Japanese patients

Purpose

Human leukocyte antigen (HLA) and immunity are related. Uveitis is also closely related to immunity. For example, the common presence of human leukocyte antigen (HLA)-DRB1*04 in the immune response is well known. The aim of this study was to investigate the relationship between visual prognosis and various HLA alleles before and after therapy in patients with unclassifiable uveitis, excluding those with Vogt-Koyanagi-Harada (VKH) disease.

Methods

This retrospective case series included 42 eyes from 22 consecutive patients with unclassifiable uveitis, excluding those with VKH disease. Visual acuity (VA), sex, refractive error, central retinal thickness (CRT), central choroidal thickness (CCT), and duration from onset to treatment were measured at initial and 6-month visits. Mean values of parameters were compared at each visit. Genotyping was performed by polymerase chain reaction amplification with sequence-specific primers.

Results

DRB1*04 showed a dominant change. No significant difference was observed in the other alleles. In DRB1*04, The mean differences in initial CCT, 6-month CCT, and 6-month VA showed statistically significant difference was found in best-corrected visual acuity (BCVA) between DRB1*04+ and DRB1*04− at the first visit. BCVA values at baseline and at the final visit were 0.13 ± 0.29 and 0.20 ± 0.36 in the DRB1*04+ and 0.00045 ± 0.20 and − 0.058 ± 0.11 in the DRB1*04− groups(p = 0.00465). Central Choroidal Thickness (CCT) values pretreatment and at the final visit after treatment were (pretreatment:361.00 ± 361.0 μm,after treatment: 286.00 ± 106.53 μm, p = 0.0174) in the DRB1*04+ group, and (pretreatment:281.3 ± 139.68 μm,after treatment:223.85 ± 99.034 μm, p = 0.0426) in the DRB1*04− group, respectively, indicating changes between baseline and the final visit. CCT was significantly greater in the DRB1*04+ group at both the initial visit and at 6 months. Multivariate analysis showed a significant difference between the presence or absence of DRB1*04 and sex.

Conclusion

HLA-DRB1*04 allele may affect visual prognosis and CCT in unclassifiable uveitis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-02222-9.

Changes in Choroidal Vascularity Index (CVI) in Intermediate Uveitis

Purpose

To investigate the longitudinal changes in choroidal vascularity index (CVI) in eyes with active and quiescent intermediate uveitis using enhanced depth imaging optical coherence tomography (EDI-OCT).

Methods

EDI-OCT images of eyes with active and quiescent intermediate uveitis were retrospectively reviewed and binarized using ImageJ software. Choroidal parameters including CVI, total choroidal area (TCA), luminal area (LA), stromal area (SA), and subfoveal choroidal thickness (SCT) were measured and compared between baseline and follow-up visits among eyes with active and quiescent intermediate uveitis.

Results

Thirty-eight eyes from 21 patients with active intermediate uveitis and 30 eyes from 17 patients with quiescent intermediate uveitis were included. CVI in eyes with active intermediate uveitis significantly increased from baseline (66.50% ± 3.40%) with resolution of inflammation on follow-up (68.82% ± 3.90%; P < 0.001). In eyes with quiescent intermediate uveitis at baseline eyes, CVI did not significantly change after follow-up (66.34% ± 3.19% to 66.25% ± 3.13%; P = 0.850).

Conclusions

CVI significantly increased when active inflammation in intermediate uveitis resolved while CVI remained unchanged at follow-up in quiescent intermediate uveitis.

Translational Relevance

CVI may be a useful noninvasive tool to monitor treatment response in intermediate uveitis. Our findings also highlight the involvement of choroidal vasculature in uveitic eyes without any clinical evidence of choroiditis.

Optical coherence tomography angiography in primary eye care

Optical coherence tomography angiography (OCT-A) is a non-invasive imaging modality for assessing the vasculature within ocular structures including the retina, macula, choroid and optic nerve. OCT-A has a wide range of clinical applications in various optometric conditions which have been independently reported in the literature. This paper aims to present a review of the current literature on the clinical application of OCT-A in optometric practice as well as to analyse and evaluate the quality of the available evidence. This review included 78 articles from a literature search conducted on 26 May 2019 across the following databases: Cochrane Library of Systematic Reviews, Medline, Scopus and Web of Science. Primary ocular pathologies discussed in this review include glaucoma, diabetic retinopathy, age-related macular degeneration, myopia, acquired and congenital macular dystrophies, epiretinal membrane, retinal vein occlusion, retinitis pigmentosa, choroidal melanoma, uveitis, central serous chorioretinopathy, amblyopia and optic neuropathies. Primary outcome variables included vessel density, foveal avascular zone area and diameter, flow velocity and flow index. This review aims to evaluate the evidence available for OCT-A applications in diagnosis and prognosis of ocular conditions in an optometric setting.

Retinal and choriocapillaris perfusion are associated with ankle-brachial-pressure-index and Fontaine stage in peripheral arterial disease

The purpose of this prospective case–control study was to assess whether parameters of retinal and choriocapillaris perfusion are altered in patients with peripheral arterial disease (PAD). Patients with PAD and healthy controls were imaged with swept-source optical coherence tomography angiography (OCT-A). Macula centered 3 × 3 mm OCT-A scans were acquired, binarized and perfusion was evaluated for vessel density (VD) and choriocapillaris non-perfused area. Clinical examination and non-invasive assessment included Fontaine staging, ankle-brachial-pressure-index (ABI) and vascular color-coded Doppler sonography. Fifty-two patients with PAD and 23 healthy controls were included. Superficial retinal VD was reduced in patients compared to controls (difference =  − 0.013, p = 0.02), decreased with higher Fontaine stage (p = 0.01) and correlated with ABI (r = 0.42, p < 0.0001, 95% confidence interval [CI] 0.23–0.58). Choriocapillaris non-perfused area was larger in patients compared to controls (difference = 3.64%, p = 0.002, 95% CI 1.38–5.90%) and significantly correlated with ABI (r =  − 0.22, p = 0.03, 95% CI − 0.40– − 0.03). Multivariate multiple regression analysis revealed a significant association of all OCT-A parameters with ABI and of deep retinal vessel density and choriocapillaris non-perfused area with Fontaine stage. In this first study of retinal and choroidal perfusion in patients with PAD we found both retinal and choroidal perfusion to be significantly impaired. OCT-A parameters could aid as indirect imaging biomarkers for non-invasive PAD staging and monitoring.

Structural Endpoints and Outcome Measures in Uveitis

Most uveitis entities are rare diseases but, taken together, are responsible for 5-10% of worldwide visual impairment which largely affects persons of working age. As with many rare diseases, there is a lack of high-level evidence regarding its clinical management, partly due to a dearth of reliable and objective quantitative endpoints for clinical trials. This review provides an overview of available structural outcome measures for uveitis disease activity and damage in an anatomical order from the anterior to the posterior segment of the eye. While there is a multitude of available structural outcome measures, not all might qualify as endpoints for clinical uveitis trials, and thorough testing of applicability is warranted. Furthermore, a consensus on endpoint definition, standardization, and "core outcomes" is required. As stipulated by regulatory agencies, endpoints should be precisely defined, clinically important, internally consistent, reliable, responsive to treatment, and relevant for the respective subtype of uveitis. Out of all modalities used for assessment of the reviewed structural outcome measures, optical coherence tomography, color fundus photography, fundus autofluorescence, and fluorescein/indocyanine green angiography represent current "core modalities" for reliable and objective quantification of uveitis outcome measures, based on their practical availability and the evidence provided so far.

Multimodal imaging in infectious and noninfectious intermediate, posterior and panuveitis

PURPOSE OF REVIEW

Given the heterogeneity of uveitis, markers of inflammation vary from patient to patient. Multimodal imaging has proven itself to be critical for accurate evaluation for disease activity and treatment response in uveitis.

RECENT FINDINGS

Ultra-widefield (UWF) fluorescein angiography and autofluorescence (AF) as well as optical coherence tomography angiography (OCTA) have provided insights into disease pathogenesis and monitoring not previously appreciated. In addition to structural retinal imaging, OCT can be used to assess the choroid, the posterior cortical vitreous and the retinal vasculature in eyes with uveitis.

SUMMARY

Multimodal ocular imaging in eyes with uveitis is critical for disease diagnosis and assessing response to treatment. UWF fluorescein angiography can detect retinal vasculitis even in the absence of overt vascular sheathing. UWF AF can help detect more chorioretinal lesions than clinically visible. OCT can be used to assess the posterior cortical vitreous, retina, large retinal vessels and choroid in uveitis. The use of multimodal imaging will likely be needed to determine clinical trial endpoints in studies evaluating therapeutics for uveitis.

Recent advances in wide field and ultrawide field optical coherence tomography angiography in retinochoroidal pathologies

Introduction: With the advent of wide field (WF) and ultra-wide field (UWF) imaging in color fundus photography and fluorescein angiography (FA), the importance of an expanded field-of-view (FOV) has been illustrated for early detection of several chorioretinal disorders. The need to bring similar utility to optical coherence tomography angiography (OCTA) is imperative.Areas covered: For this review, we explored all research items with WF or UWF on Pubmed Central and Google Scholar. Software-based methods included algorithms for motion correction, artifact reduction, image pre-processing, post-processing and montage protocols while hardware methods included swept-source OCTA, faster scanning sources, hardware-based motion tracking and image registration, scanning sources with faster speeds and lower resolution. For various disorders such as diabetic retinopathy, uveitis, vascular disorders, among others, the increased FOV showed demonstrably increased detection rates and diagnostic yield.Expert opinion: Increased FOV in OCTA imaging is a meaningful and impactful step in ophthalmic imaging. Overcoming the hardware-based limitations can potentially yield higher FOV without loss of important details. In addition to improvements in the hardware and available equipment, better software tools and image processing algorithms may greatly enhance the utility of UWF OCTA in care of patients with various retinochoroidal diseases.

Differential effects of high-intensity interval training (HIIT) on choriocapillaris perfusion in healthy adults and patients with type 1 diabetes mellitus (T1DM)

PURPOSE

To investigate the effects of a four-week high-intensity interval training (HIIT) on choriocapillaris (CC) perfusion in young healthy adults and type 1 diabetes mellitus (T1DM) patients.

METHODS

Data of two HIIT studies with baseline to follow-up comparison were retrospectively analysed. Twenty healthy participants and twenty T1DM patients without clinical signs of diabetic retinopathy were included. All participants had performed a four-week all-out HIIT protocol with a total of 8 training sessions. Changes in physical fitness were assessed using power output at the individual aerobic lactate threshold (IANT). Optical coherence tomography angiography (OCTA) imaging was performed at baseline and follow-up. CC images were analysed for number, size and total area of flow deficits (FD), mean signal intensity, signal intensity standard deviation and kurtosis of signal intensity distribution.

RESULTS

At baseline, CC OCTA revealed a lower and more heterogeneous intensity signal in T1DM eyes (mean intensity signal and standard deviation of signal intensity, p < 0.001). Percent of CC FD area was greater in T1DM eyes (p < 0.001). While T1DM patients showed greater improvement of exercise capacity at IANT than healthy controls (group×time p = 0.0403), CC FD area and standard deviation of intensity increased in healthy controls but not in T1DM patients (group×time p ≤ 0.029). Moreover, linear regression slopes of FD region distribution differed significantly at baseline and follow-up (p = 0.0002) in healthy individuals but not in T1DM patients.

CONCLUSIONS

Effects of regular physical exercise performed as HIIT on CC perfusion were only seen in healthy participants, not in T1DM patients suggesting impaired CC adaptation in T1DM.

Vascular abnormalities in uveitis

Inflammation can involve several ocular structures, including the sclera, retina, and uvea, and cause vascular changes in these tissues. Although retinal vasculitis is the most common finding associated with uveitis involving the posterior segment, other vascular abnormalities may be seen in the retina. These include capillary nonperfusion and ischemia, vascular occlusions, preretinal neovascularization, microaneurysms and macroaneurysms, and telangiectasia. Moreover, vasoproliferative tumors and subsequent coat-like response can develop secondary to uveitis. Fluorescein angiography is ideal for the investigation of retinal vascular leakage and neovascularization, while optical coherence tomography angiography can provide depth resolved images from the superficial and deep capillary plexus and can demonstrate vascular remodeling. Choroidal vascular abnormalities primarily develop in the choriocapillaris or in the choroidal stroma and can appear as flow void in optical coherence tomography angiography and filling defect and vascular leakage in indocyanine green angiography. Extensive choriocapillaris nonperfusion in the presence of choroidal inflammation can increase the risk of choroidal neovascular membrane development. Iris vascular changes may manifest as dilation of vessels in stroma due to inflammation or rubeosis that is usually from ischemia in retinal periphery secondary to chronic inflammation. More severe forms of scleral inflammation, such as necrotizing scleritis, are associated with vascular occlusion in the deep episcleral plexus, which can lead to necrosis of sclera layer and uveal exposure.

Multimodal imaging in pediatric uveitis

Pediatric uveitis accounts for up to 10% of all uveitis cases, so special attention must be paid to ensure early diagnosis as well as treatment and follow-up of these young patients in order to decrease the risk of possible ocular complications and consequently vision loss. Multimodal imaging has been an effective and important adjunct in the diagnoses and management of uveitis, especially in children. Reviewed here are the currently utilized modalities, advances, as well as their applications in juvenile idiopathic arthritis-associated uveitis, pars planitis, retinal vasculitis, tubulointerstitial nephritis and uveitis syndrome, Behçet disease, Blau syndrome, and Vogt-Koyanagi-Harada syndrome.

Advances and potential new developments in imaging techniques for posterior uveitis. Part 1: noninvasive imaging methods

The aim of this review was to identify the imaging methods at our disposal to optimally manage posterior uveitis at the present time. The focus was put on methods that have become available since the 1990s, some 30 years after fluorescein angiography had revolutionized imaging of posterior uveitis in particular imaging of the retinal vascular structures in the 1960s. We have focussed our review on precise imaging methods that have been standardized and validated and can be used universally thanks to commercially produced and available instruments for the diagnosis and follow-up of posterior uveitis. The first part of this imaging review will deal with noninvasive imaging methods, focusing on fundus autofluorescence and optical coherence tomography as well as recent developments in imaging of the posterior segment.

Optical Coherence Tomography Angiography Findings in Patients With Acute Syphilitic Posterior Placoid Chorioretinopathy

Purpose:

Acute syphilitic posterior placoid chorioretinopathy (ASPPC) is an uncommon and distinct manifestation of ocular syphilis necessitating immediate treatment. ASPPC is attributed to disruption of the choriocapillaris, retinal pigment epithelium, and photoreceptors. Optical coherence tomography angiography (OCTA) can evaluate choriocapillaris vascular flow and may provide further information about ASPPC’s disease process.

Methods:

OCTA images from 7 eyes of 4 patients with ASPPC were compared before and after treatment when available.

Results:

All eyes demonstrated increased choriocapillaris vascular flow voids in the distribution of the ASPPC lesions at initial testing. Following treatment, decreased placoid lesion size was associated with decreased flow voids on OCTA along with improved ellipsoid zone integrity in 2 patients.

Conclusions:

Disruption of choriocapillaris vascular flow in ASPPC that causes outer retinal changes can improve following treatment as suggested by OCTA imaging. Some cases may continue to demonstrate decreased flow even after appropriate therapy.

Optical Coherence Tomography-Angiography in Geographic Atrophy

Geographic atrophy (GA) represents the non-exudative late stage of age-related macular degeneration and constitutes a leading cause of legal blindness in the developed world. It is characterized by areas of loss of outer retinal layers including photoreceptors, degeneration of the retinal pigment epithelium, and rarefication of the choriocapillaris. As all three layers are functionally connected, the precise temporal sequence and relative contribution of these layers towards the development and progression of GA is unclear. The advent of optical coherence tomography angiography (OCT-A) has allowed for three-dimensional visualization of retinal blood flow. Using OCT-A, recent studies have demonstrated that choriocapillaris flow alterations are particularly associated with the development of GA, exceed atrophy boundaries spatially, and are a prognostic factor for future GA progression. Furthermore, OCT-A may be helpful to differentiate GA from mimicking diseases. Evidence for a potential protective effect of specific forms of choroidal neovascularization in the context of GA has been reported. This article aims to give a comprehensive review of the current literature concerning the application of OCT-A in GA, and summarizes the opportunities and limitations with regard to pathophysiologic considerations, differential diagnosis, study design, and patient assessment.

Retinal microvascular metrics in untreated essential hypertensives using optical coherence tomography angiography

PURPOSE

To quantify early changes of macular microvascular density, complexity, and peripapillary vessel caliber in hypertension using optical coherence tomography angiography (OCTA).

METHODS

Hypertension (137 eyes) and healthy eyes (79 eyes) as control were involved in this prospective observational study. Indices of the microcirculation included vessel density (VD), skeleton density (SD), vessel diameter index (VDI), fractal dimension (FD) and foveal avascular zone (FAZ) of superficial retinal layer (SRL) and deep retinal layer (DRL), and peripapillary vessel calibers. The correlation of these indices with mean arterial pressure (MAP) and ocular perfusion pressure (OPP) was analyzed.

RESULTS

Mean VD of DRL, SD of SRL and DRL, and FD of SRL and DRL were significantly reduced in the macula of hypertensive eyes (all P < 0.01). Meanwhile, hypertensive eyes had margin results of narrower peripapillary arteriolar caliber (P = 0.04). No significant finding was demonstrated on VD of SRL, VDI and FAZ of SRL and DRL, peripapillary total vascular caliber, and peripapillary venal caliber (all P > 0.05). SD and VD of the DRL correlated negatively with MAP (both R = - 0.152, P = 0.03).

CONCLUSION

OCTA algorithms may provide an additional inexpensive tool to aid in the preclinical assessment of hypertensive subject.

Optical coherence tomography-angiography for monitoring neovascularisations in macular telangiectasia type 2

PURPOSE

To evaluate the utility of optical coherence tomography-angiography (OCT-A) for monitoring activity, progression and response to therapy of neovascularisations (NVs) secondary to macular telangiectasia type 2 (MacTel).

METHODS

In a retrospective analysis, eyes with NVs secondary to MacTel were reviewed over a period of ≥8 months. Examinations at monthly intervals included visual acuity testing, dilated funduscopy, spectral domain-OCT and OCT-A. Eyes were treated with intravitreal VEGF (vascular endothelial growth factor)-inhibitors following a pro-re-nata (PRN) regime, and treatment decisions were based on morphological signs of activity as determined by B-scan OCT and funduscopy. Signs of neovascular activity were defined as an increase in retinal thickness, presence/increase of intraretinal/subretinal fluid and haemorrhages.

RESULTS

A total of 19 eyes from 17 patients were analysed. Patients were evaluated over a mean period of 13.4 months (range: 8.9 to 24.2). OCT-A permitted the monitoring of both treatment effects (regression) and progression (growth) of NVs, but not neovascular activity. The growth of neovascular vessels was detectable in OCT-A before signs of activity occurred on OCT. NVs showed a progressive growth over time despite PRN-treatment and preferentially grew and extended within areas characterised by a focal reduction of choriocapillaris perfusion.

CONCLUSIONS

The results indicate that OCT-A represents a useful imaging modality for monitoring NV-progression and treatment effects in MacTel. We demonstrate its advantages over conventional B-scan OCT imaging, including an earlier detection of NV-progression, and propose an adjustment of the current OCT-controlled PRN treatment regime in order to prevent NV-progression and subsequent functional loss in neovascular MacTel.

Automated thresholding algorithms outperform manual thresholding in macular optical coherence tomography angiography image analysis

Introduction

For quantification of Optical Coherence Tomography Angiography (OCTA) images, Vessel Density (VD) and Vessel Skeleton Density (VSD) are well established parameters and different algorithms are in use for their calculation. However, comparability, reliability and ability to discriminate healthy and impaired macular perfusion of different algorithms are unclear, yet, of potential high clinical relevance. Hence, we assessed comparability and test-retest reliability of the most common approaches.

Materials and methods

Two consecutive 3×3mm OCTA en face images of the superficial and deep retinal layer were acquired with swept-source OCTA. VD and VSD were calculated with manual thresholding and six automated thresholding algorithms (Huang, Li, Otsu, Moments, Mean, Percentile) using ImageJ and compared in terms of intra-class correlation coefficients, measurement differences and repeatability coefficients. Receiver operating characteristic analyses (healthy vs. macular pathology) were performed and Area Under the Curve (AUC) values were calculated.

Results

Twenty-six eyes (8 female, mean age: 47 years) of 15 patients were included (thereof 15 eyes with macular pathology). Binarization thresholds, VD and VSD differed significantly between the algorithms and compared to manual thresholding (p < 0.0001). Inter-measurement differences did not differ significantly between patients with healthy versus pathologic maculae (p ≥ 0.685). Reproducibility was higher for the automated algorithms compared to manual thresholding on all measures of reproducibility assessed. AUC was significantly higher for the Mean algorithm compared to the manual approach with respect to the superficial retinal layer.

Conclusions

Automated thresholding algorithms yield a higher reproducibility of OCTA parameters and allow for a more sensitive diagnosis of macular pathology. However, different algorithms are not interchangeable nor results readily comparable. Especially the Mean algorithm should be investigated in further detail. Automated thresholding algorithms are preferable but more standardization is needed for clinical use.

Optical coherence tomography angiography (OCTA) as a new diagnostic tool in uveitis

Background

The broad spectrum of uveitis disorders requires a multimodal imaging approach in the daily practice of an ophthalmologist. As inflammatory conditions, they have in common an alteration in leukocyte migration. In this context, optical coherence tomography angiography (OCTA) might be of great value for diagnosing or following up patients with these disorders. To date, OCTA has rather been used as an additional tool besides the well-established diagnostic imaging tools, but its complementary diagnostic features become increasingly relevant, to follow disease activity and treatment response and for the understanding of pathomechanisms of various uveitis types.

This review summarizes the possible applications of OCTA and its advantages and disadvantages as opposed to dye-based angiographies in uveitic diseases.

Main body

Hitherto gold standards in the diagnostic workup of posterior or intermediate uveitis have been angiography on a dye-based method, which is fluorescein or indocyanine green. It gives information about the status of the blood-retinal barrier and the retinal and choroidal vasculature by visualizing diffuse leakage as a state of inflammation or complications as an ischemia or choroidal neovascularization. As noninvasive methods, fundus autofluorescence depicts the status of metabolic activity of the retinal pigment epithelium and OCT or enhanced depth imaging OCT, respectively, as a depth-resolving imaging method can supply additional information.

OCTA as a non-invasive, depth-resolution imaging tool of retinal and choroidal vessels adds detailed qualitative and quantitative information of the status of retinal and choroidal vessels and bridges the gap between the mentioned conventional diagnostic tools used in uveitis.

It is important, though, to be aware of its limitations, such as its susceptibility to motion artifacts, limited comparability among different devices, and restricted contribution of information regarding the grade of disease activity.

Conclusion

OCTA as a non-invasive, depth-resolution imaging tool can give qualitative and quantitative information about the status of retinal and choroidal vessels, but also has certain limitations. Employing OCTA as a complementary rather than exclusive tool, it can give important additional information about the macro- and microvasculature under inflammatory circumstances. Thereby, it also contributes to the understanding of the pathophysiology of various uveitis entities.

Right-angled vessels in macular telangiectasia type 2

PURPOSE

To evaluate the role of right-angled vessels (RAVs) during disease progression in macular telangiectasia type 2 (MacTel).

METHODS

In this study, 100 eyes of 52 patients and 52 eyes of 26 age-related controls were examined using fundus photography, spectral-domain optical coherence tomography (SD-OCT), OCT angiography (OCT-A) and fundus fluorescein angiography (FFA). Two masked readers graded fundus photographs of patients' eyes into five disease stages according to Gass and Blodi, and evaluated all eyes for the presence of RAVs. If RAVs were present, their course and origin (arterial vs venous) was evaluated with OCT-A and FFA, respectively. Additionally, we looked for morphological correlates of these vessels on SD-OCT scans. Neovascular eyes were analysed for the presence of RAVs and for morphological changes on formation of neovascularisations (NVs).

RESULTS

In OCT-A, RAVs were already detectable in eyes with early stages (1 to 2), could be tracked from superficial to outer retinal layers and were shown to form anastomoses in the outer retina with disease progression. These vessels were of both arterial and venous origin as shown by early phase FFA. Dilated capillaries and RAVs in OCT-A corresponded to hyper-reflective alterations of the outer retina on SD-OCT scans. In 19/19 eyes, NVs were associated with the presence of RAVs, and RAVs were shown to directly connect to neovascular complexes and to undergo morphological changes upon NV formation.

CONCLUSIONS

The results emphasise the role of RAVs during disease progression from an early stage on and demonstrate their involvement in the development of secondary NVs in MacTel.

Evaluation of vascular changes in intermediate uveitis and retinal vasculitis using swept-source wide-field optical coherence tomography angiography

Purpose

To evaluate vascular changes in patients with intermediate uveitis with or without retinal vasculitis using swept-source wide-field optical coherence tomography angiography (OCTA).

Methods

This is a prospective cross-sectional study. Consecutive patients with intermediate uveitis were evaluated using wide-field OCTA. Wide-field OCTA and en-face OCT images were analysed for the presence of capillary non-perfusion and reduced perfusion, disruption of ellipsoid zone, and abnormalities on en-face wide-field retinal thickness maps, respectively, and compared with fluorescein angiography (FA) findings in a subcohort.

Results

164 eyes of 88 patients with intermediate uveitis were included. Areas of capillary non-perfusion and reduced perfusion were more frequently observed in the choroidal OCTA slab (33.3% and 49.4%), choriocapillaris (CC; 31.4% and 48%) and deep capillary plexus (DCP; 9.6% and 34.6%) than in the superficial capillary plexus (SCP; 5% and 26.3%), respectively. Intermediate uveitis with vasculitis presented more frequently with non-perfusion and hypoperfusion in the DCP (p=0.003 and p=0.05, respectively) and SCP (p=0.007 and p=0.005, respectively) than intermediate uveitis without vasculitis. Peripheral capillary leakage on FA correlated with the presence of perivascular, macular and generalised thickening on en-face wide-field thickness maps (p=0.007). Ischaemia on FA was significantly associated with non-perfusion on wide-field OCTA in SCP and DCP (p=0.019 and p=0.027, respectively).

Conclusion

Changes in the choroid, CC and DCP are more frequently found than in the SCP on wide-field OCTA in intermediate uveitis. While wide-field OCTA is a reliable tool to detect capillary non-perfusion in intermediate uveitis, it was not helpful in determining disease activity.

Trial registration number

NCT02811536.