Advances in imaging of uveitis

Epiretinal membranes in patients with uveitis: an update on the current state of management

PURPOSE

This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up, and therapeutic approach of uveitic epiretinal membranes (ERM).

METHODS

A thorough investigation of the literature was conducted using the PubMed database. Additionally, a complementary search was carried out on Google Scholar to ensure the inclusion of all relevant items in the collection.

RESULTS

ERM is an abnormal layer at the vitreoretinal interface, resulting from myofibroblastic cell proliferation along the inner surface of the central retina, causing visual impairment. Known by various names, ERM has diverse causes, including idiopathic or secondary factors, with ophthalmic imaging techniques like OCT improving detection. In uveitis, ERM occurrence is common, and surgical intervention involves pars plana vitrectomy with ERM peeling, although debates persist on optimal approaches.

CONCLUSIONS

Histopathological studies and OCT advancements improved ERM understanding, revealing a diverse group of diseases without a unified model. Consensus supports surgery for uveitic ERM in progressive cases, but variability requires careful consideration and effective inflammation management. OCT biomarkers, deep learning, and surgical advances may enhance outcomes, and medical interventions and robotics show promise for early ERM intervention.

Chronic Retinal Necrosis Associated with Toxoplasma Gondii

INTRODUCTION

Chronic retinal necrosis encompasses severe occlusive retinal vasculitis, granular retinitis, and vitritis. This phenotype has been observed in patients with limited immune dysfunction, cytomegalovirus (CMV) uveitis, and negative serology for human immunodeficiency virus (HIV).

METHODS

Case series.

RESULTS

We present two cases: an 85-year-old female and a 76-year-old male, both displaying unusual occlusive panretinal vasculopathy associated with long-standing necrotizing retinitis and vitritis. Anterior chamber taps with real-time polymerase chain reaction (PCR) were negative for herpesviruses and positive for Toxoplasma gondii in both cases. These findings are consistent with chronic retinal necrosis associated with toxoplasma gondii.

CONCLUSIONS

In elderly patients or those with limited immune dysfunction who present with chronic retinal necrosis, Toxoplasma gondii should be considered in the differential diagnosis.

Fundus autofluorescence in uveitis: from pathogenesis to imaging interpretation

PURPOSE

This review aims to summarize the current fundus autofluorescence (FAF) ailment for diagnosis and follow-up of uveitis.

METHODS

A thorough literature search was performed in the PubMed database.

RESULTS

FAF maps the retinal pigment epithelium's (RPE) health. Therefore, several posterior infectious and non. This fast, easy-to-perform, noninvasive technique can detect and manage infectious uveitis.

CONCLUSIONS

FAF serves to understand pathophysiologic mechanisms of uveitis and is a valuable prognostic indicator of themselves.

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.

Optical Coherence Tomography Angiography of the Choriocapillaris in Subclinical Toxoplasma Chorioretinitis: A Case Report

This report describes the optical coherence tomography angiography (OCTA) findings detected at the choriocapillaris slab before the clinical picture of acute toxoplasmosis choroiretinitis (TCR) by following up a patient with serial images of OCT and OCTA from the quiescent to the active stage of the disease. In this case, the increased thickness of the choroid in the OCT B-scan and the prominent flow void at the choriocapillaris slab of the OCTA were detected early in the course of the disease. OCTA is a useful imaging technique in TCR and might help in predicting the TCR lesion at the subclinical stage.

Retinal Microvascular Alterations in Patients with Quiescent Posterior and Panuveitis Using Optical Coherence Tomography Angiography

PURPOSE

To quantify retinochoroidal vascular parameters using swept-source optical coherence tomography (SS-OCTA) in quiescent posterior and panuveitis.

METHODS

In this cross-sectional study, subjects with quiescent posterior and panuveitis underwent fundus imaging using SS-OCTA (DRI Triton®, Topcon, Japan). The metrics calculated were fractal dimension (FD), foveal avascular zone (FAZ) area, retinal vascularity index (capillary density index-CDI), and choroidal vascularity index (CVI).

RESULTS

We included 38 eyes of 20 patients, 9 males aged 34.7 ± 10.5 years, 30 eyes of 30 age- and gender-matched healthy controls, 10 females aged 33.6 ± 8.5 years. Comparing patients with controls, we found a lower FD (p < .001), larger FAZ (p > .001), lower CDI in the superficial plexus (p = .019), and lower CVI (p < .001). We also found lower retinal and choroidal and thicknesses (p < .001 and p = .025, respectively).

CONCLUSIONS

Patients with quiescent posterior and panuveitis have a significantly reduced retinochoroidal vascular density compared to healthy control subjects.

Subretinal peripapillary biopsy-proven sarcoidosis: a case report

BACKGROUND

To report a case of a subretinal, unilateral, peripapillary granuloma that was diagnosed as sarcoidosis by a 27-gauge pars plana vitrectomy subretinal biopsy. Sarcoidosis is a chronic idiopathic granulomatous inflammatory disease, that has ocular involvement in 10-80% of patients. It is often mistaken for many other primary ocular diseases because the condition can involve any structure in or around the eye. Previous case reports of peripapillary sarcoidosis have either been limited to the choroid or presented with additional ocular and systemic signs, hence have not required an intraocular biopsy.

CASE PRESENTATION

A 54-year-old Filipino male presented with a 6-month history of painless blurred vision in his right eye. Fundus examination revealed a large white peripapillary lesion. Enhanced-depth imaging optical coherence tomography confirmed the subretinal location of the mass. Indocyanine green angiography demonstrated absolute hypofluorescent blockage with satellite lesions. A whole-body positron emission tomography scan demonstrated widespread lymphadenopathy, but investigations including an inguinal lymph node biopsy were inconclusive. Following growth of the peripapillary lesion and worsening vision, a 27-gauge pars plana vitrectomy subretinal biopsy was performed which confirmed sarcoidosis. He was treated with oral corticosteroids and transitioned to long term immunotherapy with methotrexate.

CONCLUSIONS

Sarcoidosis can present in the subretinal space, around the optic nerve without other ocular findings.

Imaging-based Assessment of Choriocapillaris: A Comprehensive Review

PURPOSE

Over the past two decades, advancements in imaging modalities have significantly evolved the diagnosis and management of retinal diseases. Through these novel platforms, we have developed a deeper understanding of the anatomy of the choroidal vasculature and the choriocapillaris. The recently developed tools such as optical coherence tomography (OCT) and OCT angiography (OCTA) have helped elucidate the pathological mechanisms of several posterior segment diseases. In this review, we have explained the anatomy of the choriocapillaris and its close relationship to the outer retina and retinal pigment epithelium.

METHODS

A comprehensive search of medical literature was performed through the Medline/PubMed database using search terms: choriocapillaris, choroid, quantification, biomarkers, diabetic retinopathy, age-related macular degeneration, choroidal blood flow, mean blur rate, flow deficit, optical coherence tomography, optical coherence tomography angiography, fluorescein angiography, indocyanine green angiography, OCTA, Doppler imaging, uveitis, choroiditis, white dot syndrome, tubercular serpiginous-like choroiditis, choroidal granuloma, pachychoroid, toxoplasmosis, central serous chorioretinopathy, multifocal choroiditis, choroidal neovascularization, choroidal thickness, choroidal vascularity index, choroidal vascular density, and choroidal blood supply. The search terms were used either independently or combined with choriocapillaris/choroid.

RESULTS

The imaging techniques which are used to qualitatively and quantitatively analyze choriocapillaris are described. The pathological alterations in the choriocapillaris in an array of conditions such as diabetes mellitus, age-related macular degeneration, pachychoroid spectrum of diseases, and inflammatory disorders have been comprehensively reviewed. The future directions in the study of choriocapillaris have also been discussed.

CONCLUSION

The development of imaging tools such as OCT and OCTA has dramatically improved the assessment of choriocapillaris in health and disease. The choriocapillaris can be delineated from the stromal choroid using the OCT and quantified by manual or automated methods. However, these techniques have inherent limitations due to the lack of an anatomical distinction between the choriocapillaris and the stromal choroid, which can be overcome with the use of predefined segmentation slabs on OCT and OCTA. These segmentation slabs help in standardizing the choriocapillaris imaging and obtain repeatable measurements in various conditions such as diabetic retinopathy, age-related macular degeneration, pachychoroid spectrum, and ocular inflammations. Additionally, Doppler imaging has also been effectively used to evaluate the choroidal blood flow and quantifying the choriocapillaris and establishing its role in the pathogenesis of various retinochoroidal diseases. As tremendous technological advancements such as wide-field and ultra-wide field imaging take place, there will be a significant improvement in the ease and accuracy of quantifying the choriocapillaris.

Sarcoid Uveitis: An Intriguing Challenger

The purpose of our work is to describe the actual knowledge concerning etiopathogenesis, clinical manifestations, diagnostic procedures, complications and therapy of ocular sarcoidosis (OS). The study is based on a recent literature review and on the experience of our tertiary referral center. Data were retrospectively analyzed from the electronic medical records of 235 patients (461 eyes) suffering from a biopsy-proven ocular sarcoidosis. Middle-aged females presenting bilateral ocular involvement are mainly affected; eye involvement at onset is present in one-third of subjects. Uveitis subtype presentation ranges widely among different studies: panuveitis and multiple chorioretinal granulomas, retinal segmental vasculitis, intermediate uveitis and vitreitis, anterior uveitis with granulomatous mutton-fat keratic precipitates, iris nodules, and synechiae are the main ocular features. The most important complications are cataract, glaucoma, cystoid macular edema (CME), and epiretinal membrane. Therapy is based on the disease localization and the severity of systemic or ocular involvement. Local, intravitreal, or systemic steroids are the mainstay of treatment; refractory or partially responsive disease has to be treated with conventional and biologic immunosuppressants. In conclusion, we summarize the current knowledge and assessment of ophthalmological inflammatory manifestations (mainly uveitis) of OS, which permit an early diagnostic assay and a prompt treatment.

Swept-source optical coherence tomography angiography of retinal occlusive vasculitis following brolucizumab administration: a case report

Background

We present a case of retinal occlusive vasculitis following brolucizumab administration and the first report of optical coherence tomography angiography (OCTA) findings after treatment.

Case presentation

A 71-year-old man complained of vision loss in the left eye 6 weeks after brolucizumab injection. His visual acuity was counting fingers, and examination revealed 1 + anterior chamber cells with 2 + vitreous cells. Fundus examination demonstrated vitreous haze, retinal whitening, and vascular sheathing. Fluorescein angiography revealed filling defects in the retinal arteries and veins, and OCTA showed extensive capillary nonperfusion. Under the diagnosis of brolucizumab-associated intraocular inflammation (IOI) and retinal occlusive vasculitis, topical, sub-Tenon, and systemic corticosteroids were administered. After the treatment, visual acuity improved to 20/200, and OCTA revealed gradual improvement in capillary dropout; however, with the limited improvement of reperfusion in the perifoveal areas.

Conclusions

Prompt evaluation and intensive corticosteroid treatments are required for brolucizumab-associated IOI. OCTA imaging provides detailed information on microvascular changes in the retinal vascular plexuses in brolucizumab-associated retinal occlusive vasculitis.

Microvascular changes in the recurrent cystoid macular edema secondary to posterior noninfectious uveitis on optical coherence tomography angiography

Background

Posterior uveitis represents the second most frequent type of uveitis (15–30% of all uveitis). Noninfectious posterior uveitis complicated with secondary cystoid macular edema (CME) affects the visual prognosis negatively. The objective of the current study is to detect possible microvascular changes causing relapsing uveitis-related CME using optical coherence tomography angiography (OCTA).

Methods

This is an interventional, observational, retrospective study with 1 year follow-up. Patients with noninfectious, posterior uveitis-related CME undergoing dexamethasone (DEX) implant were evaluated. Following the DEX-implant were carried out control visits after 1 month, 2-months, 4-months, 6-months, and for up 1-year. A total of 76 eyes of 38 consecutive patients with noninfectious posterior uveitis were enrolled (consecutive sample). Complicated noninfectious posterior uveitis with secondary CME was diagnosed in 56 eyes of uveitis patients (73.7%) and reviewed.

Results

Our investigation showed (1) a reduction in superficial vessel plexus (SVP) measurements within 2-month (84%), reaching 96.4% for up 1-year, (2) an irregular profile of SVP in 69.6% of cases, persisting for up 1-year; relapsing uveitis-related CME eyes with irregular superficial foveal avascular zone (FAZ) profile were in 51%, while the SVP measurements reestablished in 100% of cases. Conversely, (3) the deep vascular plexus (DVP) parameters restored in a lower number of eyes within the 2-month (39.3%), remaining abnormal in 46.4% of cases for up 1-year; despite DVP restored in 53.6% of cases for up 1 year, (4) a capillary rarefaction ring around the FAZ appeared in 80.4% of cases; the relapsing uveitis-related CME eyes with abnormal DVP parameters were present in 41% of cases, of which 92.1% showed a rarefaction ring had abnormal DVP.

Conclusions

The use of OCTA enabled the evaluation in detail of retinal microvascular changes. We suggested that the possibility of the recurrence of the uveitis-related CME depends on the persistence of modifications of the superficial and deep layers. In this regard, we propose to implement the current imaging armamentarium with OCTA for the follow-up of patients with noninfectious uveitis-related CME.

Measuring Inflammation in the Vitreous and Retina: A Narrative Review

Uveitis consists of a group of syndromes characterised by intraocular inflammation, accounting for up to 15% of visual loss in the western world and 10% worldwide. Assessment of intraocular inflammation has been limited to clinician-dependent, subjective grading. Developments in imaging technology, such as optical coherence tomography (OCT), have enabled the development of objective, quantitative measures of inflammatory activity. Important quantitative metrics including central macular thickness and vitreous signal intensity allow longitudinal monitoring of disease activity and can be used in conjunction with other imaging modalities enabling holistic assessment of ocular inflammation. Ongoing work into the validation of instrument-based measures alongside development of core outcome sets is crucial for standardisation of clinical trial endpoints and developing guidance for quantitative multi-modal imaging approaches. This review outlines methods of grading inflammation in the vitreous and retina, with a focus on the use of OCT as an objective measure of disease activity.

The Next Steps in Ocular Imaging in Uveitis

PURPOSE

To describe the future steps and advances in the field of ocular imaging in uveitis.

METHODS

Narrative review.

RESULTS

There have been numerous advances in the field of imaging in uveitis in the past decade. Advanced techniques of imaging of the vitreous, vitreo-retinal interface, retinochoroid, and the sclera can provide significant information that helps in understanding the disease pathogenesis and manifestations. Imaging also helps in establishing a diagnosis in challenging cases, along with the laboratory and other assays. Notable developments in ocular imaging include wide-field and ultra-wide field imaging (including angiographies), automated quantification of the retinochoroidal vasculature using optical coherence tomography (OCT) and OCT angiography, quantification of vitreous cells, and intraoperative use of imaging in uveitis, among others.

CONCLUSIONS

We have summarized several technological achievements in ocular imaging in the field of uveitis and provided insights into the potential future developments.

The use of optical coherence tomography angiography in comparing choriocapillaris recovery between two treatment strategies for multifocal choroiditis: a pilot clinical trial

PURPOSE

To compare differences in choriocapillaris flow deficit (CC FD) in multifocal choroiditis (MFC) between two treatment arms using optical coherence tomography angiography (OCTA).

METHODS

In this prospective randomized clinical trial, patients were randomized to either Group 1 which received standard tapering dose of oral corticosteroids, or Group 2 which received additional dexamethasone implant (or intravitreal methotrexate). The patients were followed-up until 12 weeks using OCTA and other imaging tools. CC FD and visual acuity between the two groups were compared at each visit.

RESULTS

Twenty-five subjects (17 males; 25 eyes) were studied (11 eyes in Group 1). There were no differences between the visual acuity or CC FD (1.12 versus 1.08 mm²; p = 0.86) at baseline between the groups. However, patients in Group 2 achieved better visual acuity (0.32 ± 0.23 versus 0.15 ± 0.11; p = 0.025) and CC FD (0.54 versus 0.15 mm²; p = 0.008) at 12 weeks.

CONCLUSIONS

OCTA is a useful tool in monitoring the CC FD recovery after treatment in MFC. Patients receiving intravitreal corticosteroid/methotrexate in addition to systemic corticosteroid showed greater resolution of CC FD on OCTA compared to those receiving only oral corticosteroids.

Quantitative Assessment of Experimental Ocular Inflammatory Disease

Ocular inflammation imposes a high medical burden on patients and substantial costs on the health-care systems that mange these often chronic and debilitating diseases. Many clinical phenotypes are recognized and classifying the severity of inflammation in an eye with uveitis is an ongoing challenge. With the widespread application of optical coherence tomography in the clinic has come the impetus for more robust methods to compare disease between different patients and different treatment centers. Models can recapitulate many of the features seen in the clinic, but until recently the quality of imaging available has lagged that applied in humans. In the model experimental autoimmune uveitis (EAU), we highlight three linked clinical states that produce retinal vulnerability to inflammation, all different from healthy tissue, but distinct from each other. Deploying longitudinal, multimodal imaging approaches can be coupled to analysis in the tissue of changes in architecture, cell content and function. This can enrich our understanding of pathology, increase the sensitivity with which the impacts of therapeutic interventions are assessed and address questions of tissue regeneration and repair. Modern image processing, including the application of artificial intelligence, in the context of such models of disease can lay a foundation for new approaches to monitoring tissue health.

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.

Treatment Exit Options for Non-infectious Uveitis (TOFU): Study Protocol for a Prospective Clinical Registry

Purpose: Currently, there is limited evidence regarding clinical management of non-anterior non-infectious uveitis including treatment outcomes of disease-modifying anti-rheumatic drugs (DMARDs) and their combinations. Treatment guidelines or recommendations on preferred choice of DMARD combinations and reduction and/or discontinuation strategies in quiescent uveitis are lacking. The TOFU (Treatment exit options for non-infectious uveitis) registry aims to document disease courses and to provide recommendations on DMARD treatment exit strategies.Methods: The registry is an observational, non-commercial, and non-interventional study and targets patients who are ≥18 years of age with non-infectious uveitis of the posterior segment or retinal vasculitis on or starting DMARD treatment. Data are entered prospectively at study sites through a web-based interface into electronic case report forms (eCRF) implemented in the electronic data capture software RedCap (Version 9, Vanderbilt University, USA). The collated data include ophthalmological, general medical history and patient-reported outcomes (PROs). Assessment of uveitis classification and activity follows the international Standardization of uveitis nomenclature (SUN) criteria. Patient appointment and treatment decisions remain at the discretion of the managing physician and are completely independent of participation in the registry. The study follows the tenets of the declaration of Helsinki.Conclusions: The TOFU registry captures real-life data of patients with non-infectious uveitis of the posterior segment, involving both medical personnel and patients. The study adheres to international standards and will provide important evidence and guidance in the development of guidelines.

Placoid lesions of the retina: progress in multimodal imaging and clinical perspective

Placoid lesions of the retina may be secondary to a wide spectrum of acquired inflammatory conditions that have been reported as single entities with different presentation and clinical course. These conditions include acute posterior multifocal placoid pigment epitheliopathy, persistent placoid maculopathy, serpiginous choroiditis, serpiginous-like choroiditis, relentless placoid chorioretinitis and acute syphilitic posterior placoid chorioretinitis. In this article, we will group these conditions under the name of 'placoids'. The recognition of the specific condition may be challenging in clinical practice, often resulting in diagnostic and therapeutic delay. Given the complex nature of placoids and their similarities, a systematic approach including differentiating between infectious and non-infectious aetiologies increases the chance of reaching the correct diagnosis. Detailed history and comprehensive clinical examination are the first steps to formulate a diagnostic hypothesis that should be corroborated by multimodal imaging and appropriate investigations. The advent of multimodal imaging has made it possible to extensively study placoids and revealed a constellation of specific findings that may help clinicians in the diagnostic process. The treatment of the conditions other than syphilis is complex and sometimes challenging. Our article is aimed at giving an overview of the individual entities associated with placoids and discussing the differential diagnosis. A practical and systematic approach is then proposed.

Imaging in Tubercular Choroiditis: Current Concepts

PURPOSE

Ocular tuberculosis has protean clinical manifestations. Because of its varied clinical presentation, multimodal imaging is very important to characterize the disease activity, presence of inflammation, determining therapeutic response, and detection of complications.

METHODS

Narrative review.

RESULTS

In this review, various imaging modalities employed in the management of ocular tuberculosis including fluorescein angiography (FA), indocyanine green angiography (ICGA), optical coherence tomography (OCT), and optical coherence tomography angiography (OCTA) have been reviewed. Not only do these imaging tools complement each other in providing a comprehensive assessment of the pathology, they also help in gaining valuable insights regarding the evolution of the disease.

CONCLUSIONS

Fundus imaging plays a vital role in the diagnosis and management of patients with posterior uveitis due to tuberculosis. Fundus imaging may have a useful role in defining clinical endpoints for ocular tuberculosis in the future.