Optical coherence tomography imaging in 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.

Wide-Field Fluorescein Angiography in Patients with Idiopathic Acute Anterior Uveitis

PURPOSE

To elucidate whether wide-field fluorescein angiography (WFFA) can yield additional information in patients with newly diagnosed idiopathic acute anterior uveitis (AAU).

METHODS

The WFFA was performed in patients with idiopathic AAU, and the findings were analyzed according to the scoring system by Angiography Scoring for Uveitis Nomenclature.

RESULTS

Forty-four eyes of 30 patients (22 eyes of 13 patients in the pediatric group and 22 eyes of 17 patients in the adult group) were studied. The mean age was 12.41 ± 3.92 (range, 5-18) years in the pediatric group and 42.36 ± 32.07 (range, 24-68) years in the adult group. Thirteen eyes (59%) of pediatric patients and 12 eyes (54%) of adult patients showed some evidence of posterior segment activity on the WFFA (p = .764).     Systemic treatment was administered in 53.8% of the pediatric and 5.9% of adult patients, depending on the disease severity.

CONCLUSION

Pediatric patients with idiopathic AAU may have subtle posterior segment manifestations more than adult patients, and posterior segment findings may affect the treatment preferences of physicians.

Assessment of Inner Blood-Retinal Barrier: Animal Models and Methods

Proper functioning of the neural retina relies on the unique retinal environment regulated by the blood-retinal barrier (BRB), which restricts the passage of solutes, fluids, and toxic substances. BRB impairment occurs in many retinal vascular diseases and the breakdown of BRB significantly contributes to disease pathology. Understanding the different molecular constituents and signaling pathways involved in BRB development and maintenance is therefore crucial in developing treatment modalities. This review summarizes the major molecular signaling pathways involved in inner BRB (iBRB) formation and maintenance, and representative animal models of eye diseases with retinal vascular leakage. Studies on Wnt/β-catenin signaling are highlighted, which is critical for retinal and brain vascular angiogenesis and barriergenesis. Moreover, multiple in vivo and in vitro methods for the detection and analysis of vascular leakage are described, along with their advantages and limitations. These pre-clinical animal models and methods for assessing iBRB provide valuable experimental tools in delineating the molecular mechanisms of retinal vascular diseases and evaluating therapeutic drugs.

Comprehensive Grading System for Experimental Autoimmune Uveitis in Mice

Experimental autoimmune uveitis (EAU) is the most commonly used animal model to study the progression of chronic uveitis and to test various therapies to treat the disease. However, to accurately evaluate the effectiveness of such treatments, a grading system that combines the latest imaging techniques with definitive quantitative grading thresholds is required. This study aimed to develop a comprehensive grading system that objectively evaluates EAU progression in C57BL/6J mice. EAU was induced following immunisation with interphotoreceptor retinoid-binding protein (IRBP) and pertussis toxin. Weekly fundus and optical coherence tomography (OCT) images were acquired over 12 weeks using a Micron IV imaging system. Each mouse was graded (between 0 to 4) based on changes seen on both the fundus (optic disc, retinal blood vessels and retinal tissue) and OCT (vitreous and retinal layers) images. A total EAU response (with a maximum score of 48) was calculated for each mouse based on the sum of the individual scores each week. Analysis of the clinical scores depicted a gradual increase in inflammatory signs including optic disc and vascular swelling, leukocyte infiltration in the vitreous, lesions in the retina and formation of granulomas and hyper-reflective foci in the retinal layers in EAU mice, with most signs reaching a plateau towards the end of the study period. Development of these signs into sight-threatening complications such as optic disc atrophy, structural damage to the retina and subretinal oedema were noted in 80-90% of mice suggesting consistent disease induction. Overall, a comprehensive and objective grading system encompassing all pathologies occurring in EAU mice was developed to enhance the preclinical evaluation of novel uveitis treatments.

A machine learning framework for the quantification of experimental uveitis in murine OCT

This paper presents methods for the detection and assessment of non-infectious uveitis, a leading cause of vision loss in working age adults. In the first part, we propose a classification model that can accurately predict the presence of uveitis and differentiate between different stages of the disease using optical coherence tomography (OCT) images. We utilize the Grad-CAM visualization technique to elucidate the decision-making process of the classifier and gain deeper insights into the results obtained. In the second part, we apply and compare three methods for the detection of detached particles in the retina that are indicative of uveitis. The first is a fully supervised detection method, the second is a marked point process (MPP) technique, and the third is a weakly supervised segmentation that produces per-pixel masks as output. The segmentation model is used as a backbone for a fully automated pipeline that can segment small particles of uveitis in two-dimensional (2-D) slices of the retina, reconstruct the volume, and produce centroids as points distribution in space. The number of particles in retinas is used to grade the disease, and point process analysis on centroids in three-dimensional (3-D) shows clustering patterns in the distribution of the particles on the retina.

Correlation between Morphological Characteristics of Macular Edema and Visual Acuity in Young Patients with Idiopathic Intermediate Uveitis

Background and Objectives: Macular edema (ME) is a common complication of intermediate uveitis (IU). It is often responsible for a decrease in visual acuity (VA). Three distinct patterns of macular edema have been described in intermediate uveitis, namely, cystoid macular edema (CME), diffuse macular edema (DME), and serous retinal detachment (SRD). The current study aims to describe the characteristics of macular edema in young patients with idiopathic intermediate uveitis and to correlate its features with VA using spectral domain optical coherence tomography (SD-OCT). Materials and Methods: A total of 27 eyes from 18 patients with idiopathic IU complicated by ME were included in this retrospective study. All patients underwent SD-OCT; data were gathered at the onset of ME. Best-corrected VA (BCVA) was correlated with the morphological features of ME. Results: BCVA was negatively correlated with Ellipsoid Zone (EZ) disruption (p = 0.00021), cystoid pattern (p = 0.00021), central subfield thickness (CST) (p < 0.001), and serous retinal detachment (0.037). Conclusions: In ME secondary to idiopathic IU, VA negatively correlates with Ellipsoid Zone disruption and increases in CST. Moreover, vision is influenced by the presence of cysts in the inner nuclear and outer nuclear layers and by the neuroepithelium detachment.

A systematic review of OCT and OCT angiography in retinal vasculitis

BACKGROUND

Retinal vasculitis is a component of uveitis for which the Standardisation of Uveitis Nomenclature (SUN) working group has no standard diagnostic criteria or severity grading. Fluorescein angiography is the gold standard test to assess retinal vasculitis, but is invasive and time-consuming. Optical coherence tomography (OCT) provides non-invasive detailed imaging of retinal structures and abnormalities, including blood vessel architecture and flow with OCT angiography (OCT-A). However, use of OCT in retinal vasculitis beyond assessing macular oedema, is not well established. We conducted a systematic review to understand the features of retinal vasculitis in OCT, Enhanced-depth imaging OCT (OCT-EDI) and OCT-A imaging.

METHODS

The systematic search was done in March 2022 and updated in January 2023, through PubMed, EMBASE and the Web of Science database for studies related to OCT, OCT-EDI and OCT-A findings and retinal vasculitis. Bias assessment was assessed using JBI Critical Appraisal Checklist, and any findings associated with retinal vasculitis were extracted by qualitative analysis.

RESULTS

We identified 20 studies, including 8 articles on OCT, 6 on OCT-EDI and 6 on OCT-A. The studies included analytical retrospective studies, case-series, and a case-control study. Five OCT studies reported secondary complications could be detected, and four reported retinal thickness alteration in retinal vasculitis. Five studies explored choroidal thickness alteration in OCT-EDI, and four explored capillary density alterations in retinal vasculitis using OCT-A. The heterogeneity in the studies' analysis and design precluded a meta-analysis.

DISCUSSION

There were no clear OCT, OCT-EDI or OCT-A findings that demonstrated potential to supersede fluorescein angiography for assessing retinal vasculitis. Some signs of macular structural effects secondary to retinal vasculitis may help prognostication for vision. The OCT signs of inflamed retinal vessels and perivascular tissue is an unexplored area.

Optical Coherence Tomography Angiography Findings in Ocular Toxoplasmosis with Multiple Recurrences

Ocular toxoplasmosis is the most common cause of posterior uveitis that is caused by Toxoplasma gondii infection. Humans can be infected congenitally or postnatally. The typical lesion of ocular toxoplasmosis is focal necrotizing retinitis with overlying vitritis, which lead to hyperpigmented retinochoroidal scar at resolution of lesion. Macula involvement can cause substantial visual impairment. The high incidence of disease reactivation may lead to greater risk of vision loss. Optical coherence tomography angiography (OCTA) is a non-invasive imaging method to visualize the vascular and density perfusion of the retina and choroid, which cannot be obtained by conventional Optical Coherence Tomography (OCT). In this case report, we present two cases of active ocular toxoplasmosis with multiple recurrences to study pathological changes in retinal and choroidal microvasculature. The findings reveal the involvement of all of the retinal layers in the choroid, with distinct changes in the deep retinal layer.

Use of optical coherence tomography angiography in the uveitis clinic

As optical coherence tomography angiography is revolutionizing the ophthalmology world, the uveitis community is learning to understand where and how this new powerful imaging tool fits into the management of the panorama of ocular inflammations and infections. A non-invasive method of studying the retinal and choroidal vasculature, OCTA allows for the assessment of vessel density changes during active and inactive uveitis making it the natural imaging application of choice in uveitis clinical trials. However, these data and results are of limited utility to the ophthalmologists who are looking to apply OCTA in their everyday uveitis clinic. If employed strategically, OCTA can be a powerful tool for the uveitis specialist to evaluate iris involvement in viral uveitis; to assess the integrity of the vascular layers in the settings of white dot syndromes; to distinguish inflammatory choroidal neovascularization from outer retinal avascular inflammatory material; and to diagnose and follow infectious choroidal granulomas and satellite foci of chorioretinal inflammation without the need to administer dyes. The present review will analyze all the recent publications that apply OCTA in uveitis to offer the reader a guide on how to maximize the utility of this imaging modality in a clinical practice.

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.

Review for Diagnostics of the Year: Inflammatory Choroidal Neovascularization – Imaging Update

Inflammatory choroidal neovascularization (iCNV) is a rare complication of uveitis but is a major cause of vision compromise in affected patients. Fluorescein angiography (FA) has been the gold standard for diagnosis. However, it is an invasive modality and when used alone, it might be difficult to distinguish iCNV from inflammatory lesions. Optical coherence tomography (OCT) is a noninvasive and rapid imaging modality that can provide additional features to diagnose iCNV. OCT angiography (OCTA) uses intrinsic motion contrast to visualize flow and is useful to distinguish iCNV from inflammatory lesions. However, its role in evaluating iCNV activity and treatment response is still unclear and more studies are required to reach consensus. In conclusion, the use of data from multimodal imaging is necessary to identify and promptly treat iCNV, thus preserving patient vision.

Ocular toxoplasmosis: a review of the current diagnostic and therapeutic approaches

PURPOSE

This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up and therapeutic approach of ocular toxoplasmosis focusing mainly on the postnatally acquired form of the disease.

METHODS

A meticulous literature search was performed in the PubMed database. A supplementary search was made in Google Scholar to complete the collected items.

RESULTS

Ocular toxoplasmosis is one of the most frequent infectious etiologies of posterior uveitis. It typically presents with retinochoroiditis. Setting an accurate diagnosis depends to a considerable degree on detecting characteristic clinical characteristics. In addition to the evaluation of clinical features, the diagnosis of toxoplasmosis relies at a large degree on serologic testing. The detection of the parasite DNA in the aqueous or vitreous humor can provide evidence for a definitive diagnosis. The current mainstay for the treatment, if necessary, is the use of oral antibiotic with systemic corticosteroids. Recent evidence suggests other therapeutic approaches, such as intravitreal antibiotics can be used.

CONCLUSION

Recent developments in the diagnostic and therapeutic approach have contributed to preventing or limiting vision loss of patients suffering from ocular toxoplasmosis. Further studies are required to provide a better understanding of epidemiology, pathogenesis, diagnosis, and treatment with a significant impact on the management of this challenging clinical entity.

NOVEL OPTICAL COHERENCE TOMOGRAPHY FINDINGS OF A CASE OF SYMPATHETIC OPHTHALMIA AFTER 23-GAUGE VITRECTOMY

PURPOSE

Sympathetic ophthalmia (SO) is a rare panuveitis after trauma to one eye. We present a case of SO after 23-gauge transconjunctival vitrectomy, including optical coherence tomography evidence of response to treatment. To our knowledge, this is the first SO case report to include spectral domain optical coherence tomography images of Dalen-Fuchs nodules.

METHODS

Observational case report of a case of SO after two pars plana vitrectomies in the fellow eye.

RESULTS

A 67-year-old woman who had an operation for her pseudophakic left eye for a macula-off retinal detachment. She had two surgeries and later on had a total retinal detachment with vision of no perception of light. Eighteen months later, she presented back with a panuveitis with vitritis in her other eye and a visual acuity of 6/18. Dalen-Fuchs denoting SO was found. Treatment was commenced, and multimodal imaging was performed.

CONCLUSION

Sympathetic ophthalmia is a known complication after vitrectomy. Optical coherence tomography can be invaluable in monitoring diagnosis and progression of Dalen-Fuchs nodules.

In vivo optical molecular imaging of inflammation and immunity

Inflammation is the phenotypic form of various diseases. Recent development in molecular imaging provides new insights into the diagnostic and therapeutic evaluation of different inflammatory diseases as well as diseases involving inflammation such as cancer. While conventional imaging techniques used in the clinical setting provide only indirect measures of inflammation such as increased perfusion and altered endothelial permeability, optical imaging is able to report molecular information on diseased tissue and cells. Optical imaging is a quick, noninvasive, nonionizing, and easy-to-use diagnostic technology which has been successfully applied for preclinical research. Further development of optical imaging technology such as optoacoustic imaging overcomes the limitations of mere fluorescence imaging, thereby enabling pilot clinical applications in humans. By means of endogenous and exogenous contrast agents, sites of inflammation can be accurately visualized in vivo. This allows for early disease detection and specific disease characterization, enabling more rapid and targeted therapeutic interventions. In this review, we summarize currently available optical imaging techniques used to detect inflammation, including optical coherence tomography (OCT), bioluminescence, fluorescence, optoacoustics, and Raman spectroscopy. We discuss advantages and disadvantages of the different in vivo imaging applications with a special focus on targeting inflammation including immune cell tracking.

Foveal Pit Morphology Characterization: A Quantitative Analysis of the Key Methodological Steps

Disentangling the cellular anatomy that gives rise to human visual perception is one of the main challenges of ophthalmology. Of particular interest is the foveal pit, a concave depression located at the center of the retina that captures light from the gaze center. In recent years, there has been a growing interest in studying the morphology of the foveal pit by extracting geometrical features from optical coherence tomography (OCT) images. Despite this, research has devoted little attention to comparing existing approaches for two key methodological steps: the location of the foveal center and the mathematical modelling of the foveal pit. Building upon a dataset of 185 healthy subjects imaged twice, in the present paper the image alignment accuracy of four different foveal center location methods is studied in the first place. Secondly, state-of-the-art foveal pit mathematical models are compared in terms of fitting error, repeatability, and bias. The results indicate the importance of using a robust foveal center location method to align images. Moreover, we show that foveal pit models can improve the agreement between different acquisition protocols. Nevertheless, they can also introduce important biases in the parameter estimates that should be considered.

Ultra-Widefield Fluorescein Angiography to Monitor Therapeutic Response to Adalimumab in Behcet's Uveitis

Purpose: To investigate the role of ultra-widefield fluorescein angiography (UWFA) for monitoring therapeutic response to adalimumab in patients with Behcet's uveitis.Methods: Patients with Behcet's uveitis treated with adalimumab for ≥30 weeks were included. Intraocular inflammation, best-corrected visual acuity, systemic medications, and UWFA scores were evaluated.Results: Thirty-eight eyes of 20 patients were included. Significant decreases in grading of anterior chamber cells and vitreous haze were observed at 6, 14, and 30 weeks after adalimumab administration (p < .001 for all). UWFA scores on vascular and capillary leakage were decreased at week 6 and further improved at weeks 14 and 30. Moreover, UWFA score further decreased at 14 and 30 weeks, even after manifest inflammation became quiescent at 6 weeks. (p = .004 and 0.001, respectively).Conclusion: UWFA scores significantly improved in Behcet's uveitis patients treated with adalimumab, and further improvement of UWFA scores was found in patients with a clinically quiescent inflammatory state.

[Application of high-resolution optical coherence tomography for visualization of eye structures in uveitis of different localization]

The article presents an analysis of publications in main Russian and foreign journals devoted to the use of optical coherence tomography in intravital visualization of the structures of the eye for diagnosis, assessment of the changes during relapses, recovery and remission stages, as well as the effectiveness of treatment for uveitis of different localization. It describes in detail the results of studies conducted using spectral optical coherence tomography, changes in the anterior chamber and cornea in uveitis of the anterior localization, morphological changes in the vitreous body, vitreomacular interface, retina, choroid and optic disc in the anterior and posterior localization of inflammation, and presents the features of OCT diagnosis in a number of nosological forms of uveitis based on the literature data.

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.

Widefield Fundus Fluorescein Angiography Features of Uveitis Associated with Juvenile Idiopathic Arthritis

PURPOSE

To evaluate the wide-field fundus fluorescein angiography (WFA) characteristics of uveitis associated with juvenile idiopathic arthritis (JIA-uveitis).

METHODS

Retrospective review of records. WFA with Spectralis (Heidelberg) of JIA-uveitis patients were analyzed using the scoring system by Angiography Scoring for Uveitis Nomenclature.

RESULTS

Thirty-seven eyes of 20 patients were studied. A total score of at least 1 was noted in 27 eyes (72.97%). WFA features included optic disc hyperfluorescence (51.35%), macular leakage (27.03%), retinal vascular staining/leakage at posterior pole (27.03%) and peripheral retina (64.86%), capillary leakage at the posterior pole (37.84%), and peripheral retina (59.46%). A decision to change the management plan was made in 8 of 9 patients with bilateral quiet anterior chambers after WFA results.

CONCLUSION

More than 70% of JIA-uveitis eyes showed some WFA-evidence of posterior segment inflammation, which changed the course of therapy for a major proportion of patients with no clinically active anterior chamber inflammation.

Uveitis as a Confounding Factor in Retinal Nerve Fiber Layer Analysis Using Optical Coherence Tomography

PURPOSE

To investigate the retinal nerve fiber layer thickness (RNFLT) in uveitic eyes and search for the associations with uveitis activity, etiology and location.

METHODS

The files of 76 patients with uveitis and 76 controls were scanned. Associations of RNFLT were analyzed using generalized linear models.

RESULTS

The RNFLT was significantly higher in patients with uveitis (p < .001). Active uveitis patients had a thicker RNFL than the controls and the patients with quiescent uveitis (p < .001). Anterior uveitis was associated with thinner RNFL in global and inferotemporal quadrant (p = .011 and 0.013, respectively). Thickening of RNFL was associated with posterior uveitis and Behçet's disease in all quadrants (p < .001) and idiopathic uveitis in the superonasal and nasal quadrants (p = .001).

CONCLUSION

Active uveitis, as well as posterior uveitis and Behcet's disease-associated uveitis, is a major confounding factor in RNFL analysis and therefore detection of glaucoma.

Behçet's Uveitis: Current Diagnostic and Therapeutic Approach

Behçet's disease is a chronic, multisystem inflammatory disorder characterized by relapsing inflammation. Although its etiopathogenesis has not yet been clarified, both the adaptive and innate immune systems, genetic predisposition, and environmental factors have all been implicated. It is more frequent and more severe in males in the third and fourth decades of life. The eye is the most frequently involved organ in the course of the disease. Ocular involvement (Behçet's uveitis) is characterized by bilateral recurrent non-granulomatous panuveitis and occlusive retinal vasculitis. Recurrent inflammatory episodes in the posterior segment may lead to permanent vision loss due to irreversible retinal damage and complications such as macular scarring, macular atrophy, and optic atrophy. Early and aggressive immunomodulatory treatment and the use of biologic agents when needed are crucial for preventing recurrences and improving visual prognosis.

Role of choroidal thickness assessment in unilateral acute anterior uveitis

Purpose:

The aim of our study was to investigate the change in the subfoveal choroidal thickness in unilateral acute anterior uveitis with treatment. Choroidal inflammation is uncommon but can occur in the acute stage of anterior uveitis.

Methods:

All diagnosed patients with the first episode of unilateral acute anterior uveitis were included in the study conducted for a period of July 2017–July 2018. Choroidal thickness at subfoveal region was measured with spectralis spectral domain optical coherence tomography using enhanced depth-imaging scans. Standardized, masked manual measurement of the choroidal thickness was performed in the center of the ETDRS fields. The unaffected fellow eye of the same patient was taken as a control group and their subfoveal choroidal thickness was measured. Follow up of the patients was done at 2 weeks posttreatment to reevaluate the choroidal thickness.

Results:

A total of 61 eyes of 61 patients with unilateral acute anterior uveitis were included in the study. The mean central subfoveal choroidal thickness was significantly higher (304.82 ± 73.17 μm) as compared to that of controls (251.28 ± 66.38 μm) at presentation (P < 0.001). Following treatment and at two weeks follow up, the subfoveal choroidal thickness significantly reduced from 304.82 ± 73.17 to 274.46 ± 63.82 μm (P < 0.001). Also the subfoveal choroidal thickness was positively correlated with visual acuity (r = 0.22, P < 0.251) before treatment.

Conclusion:

Acute anterior uveitis is associated with an increase in the subfoveal choroidal thickness followed by the significant decrease in choroidal thickness with treatment, suggesting that choroid is also inflamed along with anterior segment inflammation.

Optical coherence tomography angiography in uveitis

Before the introduction of optical coherence tomography angiography (OCTA) in the early 2000s, dye-based angiography was considered the “gold standard” for the diagnosis and monitoring of ocular inflammation. OCTA is a novel technique, which demonstrates capillary networks based on the amount of light returned from moving blood cells, providing further information on pathophysiological changes in uveitis.

The aim of this review is to describe the basic principles of OCTA and its application to ocular inflammatory disorders. It particularly emphasizes on its contribution not only in the diagnosis and management of the disease but also in the identification of possible complications, comparing it with fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA). Although the advent of OCTA has remarkably enhanced the assessment of uveitic entities, we highlight the need for further investigation in order to better understand its application to these conditions.

Spectral domain optical coherence tomography as an adjunctive tool for screening Behçet uveitis

Background

This study investigated the association of central macular thickness (CMT) and macular volume (MV) with severity of Behçet uveitis in the absence of macular edema (ME).

Methods

This retrospective, interventional study included a total 131 treatment-naïve Behçet patients with varying degree of uveitis in the absence of ME. The mean CMT and MV were obtained by spectral domain optical coherence tomography (SD ODT). The patients were classified according to the anatomical classification of Behçet uveitis. The main outcome measure was comparison of mean CMT and MV with the types of Behçet uveitis.

Results

Sixty patients (45.8%) with no uveitis, 41 patients (31.3%) with anterior uveitis, 18 patients (13.7%) with posterior uveitis, and 12 patients (9.2%) with panuveitis. The mean CMT were 261.6±22.2 μm in no uveitis, 268.1±17.8 μm in anterior uveitis, 306.4±32.9 μm in posterior uveitis, and 300.4±44.0 μm in panuveitis (P < 0.001). The mean MV was 8.7±0.3 mm³ in those without uveitis, 8.8±0.3 mm³ in anterior uveitis, 9.9±1.1 mm³ in those with posterior uveitis, and 9.7±0.4 mm³ in panuveitis (P < 0.001). Types of Behçet uveitis was the only significant factor correlated with the mean CMT (B = 18.170, β = 0.408, P < 0.001) and the mean MV (B = 0.328, β = 0.652, P < 0.001).

Conclusions

The mean CMT and MV were significantly thicker in the Behçet uveitis with posterior involvement. SD OCT can be used for an adjunctive tool for screening Behçet uveitis, especially for the presence of posterior involvement.

Analysis of choroidal and central foveal thicknesses in acute anterior uveitis by enhanced-depth imaging optical coherence tomography

Background

Currently, there are a limited number of reports of structural changes in the retina and choroid in acute anterior uveitis (AAU). The aim of this study was to evaluate choroidal and central foveal thicknesses during episodes of AAU.

Methods

The medical records of 120 patients with AAU and 120 healthy subjects matched for age, sex, and spherical equivalent of refractive error were reviewed. Subjects were divided into group 1 (AAU-affected eyes), 2 (unaffected fellow eyes), and 3 (healthy control eyes).

Results

In the uveitis group, etiologic diagnoses included human leukocyte antigen (HLA)-B27-associated (n = 71) and idiopathic (n = 49) AAU. The mean subfoveal choroidal thicknesses (SFCTs) in groups 1–3 were 326.7 ± 64.2, 296.1 ± 66.6, and 294.9 ± 41.7 μm, respectively. The corresponding mean central foveal thicknesses (CFTs) were 273.5 ± 29.3, 264.4 ± 24.6, and 263.0 ± 30.8 μm, respectively. The AAU group exhibited a significantly greater SFCT than the control groups (P < .001). Relative to the control group, while eyes with idiopathic AAU exhibited a significantly greater CFT, those with HLA-B27-associated AAU exhibited no such significant difference. Anterior chamber cell grade was not associated with SFCT or CFT.

Conclusions

The SFCT increased significantly during AAU. This indicates the importance of OCT examination for detection of subclinical choroidal and retinal changes in all types of AAU.

Vitreomacular Interface Disorders in Behçet's Uveitis

Objectives:

To determine the prevalence of vitreomacular interface (VMI) disorders in patients with Behçet’s uveitis and assess the relationship between VMI disorders and clinical characteristics.

Materials and Methods:

The macular optical coherence tomography (OCT) images of 160 eyes of 96 patients with Behçet’s uveitis who were being followed in the Uvea-Behçet’s clinic were assessed retrospectively for VMI disorders including posterior vitreous detachment (PVD), epiretinal membrane (ERM), vitreomacular adhesion (VMA), vitreomacular traction (VMT), full-thickness macular hole (FTMH), lamellar hole (LH) and pseudohole.

Results:

Twenty-four patients (25%) with unilateral and 72 patients with bilateral uveitis were included in the study. Six (30%) of 20 eyes with anterior uveitis and 57 (40.7%) of 140 eyes with posterior uveitis, in total 63 (39.4%) eyes of 160 eyes had at least one VMI disorder. PVD was detected in 4 eyes (2.5%), ERM in 48 eyes (30%), VMA in 12 eyes (7.5%), and LH in 1 eye (0.6%). None of the eyes had VMT, FTMH, or pseudohole. ERM was detected in 13 eyes (8.1%) on fundus examination and 48 (30%) eyes by OCT (p=0.001). VMI was detected in 12 (50%) of 24 eyes with prior intraocular surgery and 51 (37.5%) of 136 eyes without. The mean duration of uveitis was 7.3±5.8 years in patients with VMI disorders and 5.8±7.7 years in patients without (p=0.04). There was no relation between VMI disorders and anatomic location of uveitis, history of past ocular surgery, number of ocular/periocular steroid injections, or visual acuity.

Conclusion:

VMI disorders are common in patients with Behçet’s uveitis. Their frequency increases with the duration of uveitis. OCT is more sensitive than fundus examination in the detection of VMI disorders.

Pearls and pitfalls of optical coherence tomography angiography in the multimodal evaluation of uveitis

BACKGROUND

Optical coherence tomography angiography (OCTA) employs a novel imaging algorithm that detects the amplitude or phase decorrelation of blood cell movement. It thus provides a flow map with depth-resolved visualization of the various vascular layers in the posterior pole of the eye including the retina capillary plexus and the choroid. In the past 3 years, the number of research papers on the subject of OCTA in retinal diseases has grown exponentially including important applications in the field of uveitis. While the study of OCTA in uveitic diseases has gained remarkable relevance worldwide, interpretation can be challenging, and many limitations exist in optimally using this advanced system in uveitic eyes. The aim of this review is to describe the many significant applications of OCTA in uveitis disorders and to outline the various limitations that can confound interpretation and support uveitis specialists in the integration of OCTA in the multimodal imaging approach to inflammatory diseases.

MAIN BODY

Unlike conventional angiography that can dynamically detect inflammation and leakage of dye from retinal vessels, OCTA provides other important biomarkers of inflammation. Detailed microvascular reconstruction of normal and abnormal blood vessels and quantitative evaluation are advantages of OCTA analysis. OCTA can therefore non-invasively detect choroidal neovascularization that may complicate inflammatory disorders, and with remarkable depth-resolved capability, OCTA can identify and quantitate flow loss as a manifestation of ischemia and/or inflammation. The areas of flow deficit on OCTA at the level of the inner choroid often co-localize with hypofluorescent lesions with indocyanine green angiography. These regions of presumed choriocapillaris ischemia may occur in placoid disorders. Space-occupying granulomas may occur in disorders such as sarcoid and may or may not co-localize with choriocapillaris ischemia on ICG angiography. Blocking or shadowing artifacts should be excluded when evaluating inner choroidal abnormalities with OCT angiography. Fundus autofluorescence may assess the metabolic function of the retinal pigment epithelium (RPE) and the viability of the overlying photoreceptors and thus the activity of inflammation associated with uveitic lesions. The photoreceptors are physiologically maintained by the diffusion of oxygen from the choriocapillaris below and, to a lesser extent, from the deep retinal capillary plexus above. The depth-resolved capability of OCTA may therefore provide additional significant microvascular information about these vascular layers that may be driving the development of hyper-autofluorescent RPE inflammation and photoreceptor loss.

CONCLUSIONS

The implementation of OCTA in the evaluation and management of uveitis disorders is being spurred by our greater knowledge and understanding of its application. In order to take full advantage of this exciting new imaging modality, however, uveitis specialists must understand the limitations of interpretation and potential artifact-related pitfalls in assessment and should continue to support evaluation with multimodal imaging to best optimize diagnoses and treatment of inflammatory diseases.

Uveitis: a sight-threatening disease which can impact all systems

Uveitis describes a group of conditions characterised by intraocular inflammation. The term uveitis technically describes inflammation of the uvea which comprises the iris, ciliary body and choroid, however now encompasses inflammation of adjacent intraocular structures such as the retina, vitreous and optic nerve. Uveitis is a significant cause of blindness worldwide, but its impact is generally underappreciated due to a lack of awareness and understanding of the condition among the public and most non-ophthalmic healthcare professionals. In this review, we provide an introduction to uveitis for the non-specialist, outlining the clinical presentations that should raise the suspicion of the disease, the signs that should be looked for and a framework in which to understand the condition. We show how a logical approach to classifying uveitis by aetiology and anatomical focus of disease provides the basis for treatment strategies (drug and route of administration) and clinical presentation and prognosis. We also show why understanding uveitis is helpful to clinicians working in almost every speciality due to the wide-ranging associations with systemic disease.

Systemic vasculitis and the eye

PURPOSE OF REVIEW

The primary systemic vasculitides represent a spectrum of rare but life-threatening conditions that may also affect the eye in various forms. This article reviews recently published data on ocular manifestations of systemic vasculitis.

RECENT FINDINGS

Early diagnosis and timely treatment has led to better visual outcomes in giant cell arteritis (GCA). Gene expression from orbital tissues could distinguish granulomatosis with polyangiitis (GPA) from sarcoidosis and Graves disease, but not from idiopathic orbital inflammation. Rituximab was an effective therapeutic option in ocular GPA. An ocular attack severity scoring system, flare levels, fluorescein angiography and optical coherence tomography parameters have been suggested as predictors of visual prognosis in Behçet disease. Efficacy of tumor necrosis factor-alpha inhibitors, interferon α and anti-interleukin-1 agents was shown in noncontrolled studies of ocular Behçet disease.

SUMMARY

Widely used fast-track pathway care as well as ocular imaging to detect subclinical involvement may enable earlier diagnosis of GCA and prevention of permanent visual loss. Orbital inflammation may not remain idiopathic with advances in gene expression profiling of orbital tissues. With an increased availability and the use of biologic agents, visual prognosis will improve in patients with severe ocular complications of systemic vasculitides.

Recent advances in managing and understanding uveitis

Uveitis is a sight-threatening disease entity with intraocular inflammation that arises from various causes. It mainly affects working-age individuals and may lead to irreversible visual loss if not treated properly in a timely manner. This article reviews recent advances in the management and understanding of uveitis since 2014, including treatment with new immunosuppressive therapies that use biological agents, local therapy with steroid implants, and imaging studies for the evaluation of uveitis.

Failure to Integrate Quantitative Measurement Methods of Ocular Inflammation Hampers Clinical Practice and Trials on New Therapies for Posterior Uveitis

Uveitis is one of the fields in ophthalmology where a tremendous evolution took place in the past 25 years. Not only did we gain access to more efficient, more targeted, and better tolerated therapies, but also in parallel precise and quantitative measurement methods developed allowing the clinician to evaluate these therapies and adjust therapeutic intervention with a high degree of precision. Objective and quantitative measurement of the global level of intraocular inflammation became possible for most inflammatory diseases with direct or spill-over anterior chamber inflammation, thanks to laser flare photometry. The amount of retinal inflammation could be quantified by using fluorescein angiography to score retinal angiographic signs. Indocyanine green angiography gave imaging insight into the hitherto inaccessible choroidal compartment, rendering possible the quantification of choroiditis by scoring indocyanine green angiographic signs. Optical coherence tomography has enabled measurement and objective monitoring of retinal and choroidal thickness. This multimodal quantitative appraisal of intraocular inflammation represents an exquisite security in monitoring uveitis. What is enigmatic, however, is the slow pace with which these improvements are integrated in some areas. What is even more difficult to understand is the fact that clinical trials to assess new therapeutic agents still mostly rely on subjective parameters such as clinical evaluation of vitreous haze as a main endpoint; whereas a whole array of precise, quantitative, and objective modalities are available for the design of clinical studies. The scope of this work was to review the quantitative investigations that improved the management of uveitis in the past 2-3 decades.

Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) - Report 1: Epidemiology and Classification

PURPOSE

To report the epidemiology and classification of ocular inflammation at a tertiary eye care center in Singapore.

METHODS

Retrospective cohort study of the clinical records of consecutive new cases from the Ocular Autoimmune Systemic Inflammatory Infectious Study (OASIS) database from 2004-2015.

RESULTS

A total of 2200 patients were studied from the OASIS database. The most common anatomic diagnosis was anterior uveitis (55.9%), posterior uveitis (17.5%), panuveitis (9.6%), and intermediate uveitis (4.7%). In addition, scleritis (6.1%), keratouveitis (2.8%), retinal vasculitis (2.2%), and episcleritis (1.2%) were observed. Etiology was established in 65.1%, with 35.2% of patients associated with non-infectious etiologies. The most common etiologies found were presumed tuberculosis (7.2%), followed by cytomegalovirus infection (6.9%), herpetic infection (6.3%), HLA-B27-associated anterior uveitis (4.2%), and ankylosing spondylitis (3.8%).

CONCLUSIONS

The pattern of ocular inflammation in Singapore has similarities with both Western and Asian populations. Anterior uveitis was the most common, with non-infectious etiologies being slightly more common than infectious etiologies.

Spectral-domain optical coherence tomography findings of the macula in 500 consecutive patients with uveitis

PurposeTo analyze the macular structure in a large series of consecutive patients with different types of uveitis using spectral-domain optical coherence tomography (SD-OCT).Patients and methodsFive hundred eyes of 500 consecutive patients with anterior, intermediate, posterior, and panuveitis underwent standardized macular examination using SD-OCT. Central retinal thickness (CRT), macular volume (MV), and presence of cystoid macular edema (CME), diffuse macular edema (DME), serous retinal detachment (SRD), epiretinal membrane with (ERM+) and without (ERM-) retinal surface wrinkling were determined.ResultsThe anatomic location of inflammation affected significantly CRT and MV (P<0.001, respectively), with the highest values in intermediate and panuveitis. CME was seen in 25% of all uveitic eyes, DME in 11%, SRD in 8%, ERM+ in 18%, and ERM- in 13%. CME was most frequent in intermediate (40%) and panuveitis (36%); DME was most frequent in panuveitis (18%) and posterior uveitis (17%); SRD was most frequent in panuveitis (15%) and posterior uveitis (10%); ERM+ was most frequent in panuveitis (45%) and intermediate uveitis (30%); and ERM- was most frequent in intermediate (14%) and posterior uveitis (15%).ConclusionSD-OCT of the macula is recommended for all uveitis patients. CRT, MV, and the incidence of CME were highest in intermediate and panuveitis.

Using optical coherence tomography to evaluate macular changes after surgical management for rhegmatogenous retinal detachment

Incomplete visual recovery, color vision defects, or persistent metamorphopsia may persist even after successful surgery for rhegmatogenous retinal detachment (RRD), especially in cases of RD with macula off, suggesting microstructural macular damage that standard fundus biomicroscopy could not detect. We compared spectral-domain optical coherence tomography imaging with preoperative and postoperative visual acuity to evaluate the relationship between morphological changes in the outer retina and visual outcome after successful repair of RRD with macula on or off. We enrolled 43 patients (43 eyes) with successful repair of RRD and a minimum 6-month follow up after surgery in this retrospective research. Patients accepted spectral-domain optical coherence tomography postoperatively and visual acuity examination preoperatively and postoperatively. The mean age of the patients was 48.74 ± 12.68 years (range: 16-77 years). The mean visual acuity (logarithm of minimal angle of resolution) before surgery was 0.87 ± 0.70. Disrupted ellipsoid zone was noted in one of 11 eyes in the macula-on group (9.1%) and 19 of 32 eyes in the macula-off group (59.4%). Disrupted external limiting membrane (ELM) was noted in no eye in the macula-on group (0%) and 11 of 32 eyes in the macula-off group (34.4%). The macula-off group was associated with better postoperative visual gains than the macula-on group (p = 0.013). Patients with integrity of the ellipsoid zone and ELM were associated with significant visual improvement than patients with disruption of the ellipsoid zone or ELM.

Adjunctive use of systematic retinal thickness map analysis to monitor disease activity in punctate inner choroidopathy

A challenge in the management of ‘white dot syndromes’ is the lack of sensitive objective measures of disease activity. Retinal thickness maps from spectral domain optical coherence tomography (SD-OCT) inform treatment decisions in other retinal conditions such as age-related macular degeneration and diabetic maculopathy. In this report, we demonstrate their value in providing quantitative monitoring of a patient with punctate inner choroidopathy (PIC). Retinal thickness maps referenced against a baseline scan reliably detected focal areas of increased macular volume in active PIC lesions during symptomatic episodes, highlighting these as ‘hot spots’ that could be quantified, providing an objective basis for treatment decisions.

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

PURPOSE

To compute choroidal vascularity index (CVI) using an image binarization tool on enhanced depth imaging (EDI)-optical coherence tomography (OCT) scans as a non-invasive optical tool to monitor progression in panuveitis and to investigate the utility of volumetric data from EDI-OCT scans using custom image analysis software.

MATERIALS AND METHODS

In this retrospective cohort study, segmented EDI-OCT scans of both eyes in 19 patients with panuveitis were taken at baseline and at 3-month follow-up and were compared with EDI-OCT scans of normal eyes. Subfoveal choroidal area was segmented into luminal (LA) and stromal interstitial area (SA). Choroidal vascularity index (CVI) was defined as the proportion of LA to the total circumscribed subfoveal choroidal area (TCA).

RESULTS

The mean choroidal thickness was 265.5±100.1μm at baseline and 278.4±102.6μm at 3 months follow up (p = 0.06). There was no statistically significant difference in TCA between study and control eyes (p = 0.08). CVI in the control group was 66.9±1.5% at baseline and 66.4±1.5% at follow up. CVI was 74.1±4.7% at baseline and 69.4±4.8% at 3 months follow up for uveitic eyes (p<0.001). The % change in CVI was 6.2 ±3.8 (4.3 to 8.0) for uveitic eyes, which was significantly higher from % change in CVI for control eyes (0.7±1.1, 0.2 to 1.3, p<0.001).

CONCLUSION

The study reports composite OCT-derived parameters and CVI as a possible novel tool in monitoring progression in panuveitis. CVI may be further validated in larger studies as a novel optical tool to quantify choroidal vascular status.