Quantification of Anterior Chamber Cells in Children with Uveitis Using Anterior Segment Optical Coherence Tomography

Imaging-Based Detection of Anterior Chamber Inflammation: A Comparative Diagnostic Accuracy Study

PURPOSE

We investigated the impact of operator parameters on the diagnostic performance of anterior-segment optical coherence tomography (AS-OCT) in anterior uveitis.

DESIGN

Prospective comparative diagnostic analysis.

METHODS

Setting: Single site.

STUDY POPULATION

Children younger than 18 years with anterior uveitis, recruited consecutively.

OBSERVATION PROCEDURES

Index testing: Optovue RTVue80 AS-OCT using "low-volume" (LV, horizontal and vertical cross-sections) and "high-volume" (HV, 68 horizontal cross-sections) protocols. Reference testing: slitlamp examination with anterior chamber inflammation graded using standardization of uveitis nomenclature (SUN).

MAIN OUTCOME MEASURE

Index test performance metrics (sensitivity, specificity, and likelihood ratios), utility for "ruling-in" and "ruling-out" disease (positive/negative predictive values, PPV/NPV), receiver operating characteristic curves to explore the impact of different imaging-derived metrics, multivariable multilevel regression analyses to quantify correlation of index to reference testing, and repeatability indices across protocols.

RESULTS

A total of 40 children (77 eyes: 51 eyes at SUN grade 0, 10 at SUN 0.5+, 8 at SUN 1+, and 8 SUN ≥2+ or higher) were included. There was high repeatability across protocols (0.98, P < .001, 95% CI: 0.75-1.0). OCT resulted in strong predictive values for "ruling-out" (LV-scan NPV 82.9%, 95% CI: 71.5%-90.4%; HV-scan NPV 100%, 95% CI: 3%-100%) but a less predictive value for "ruling-in" SUN ≥0.5+ (LV-scan PPV 52.8%, 95% CI: 41.5%-63.7%; HV-scan PPV 34.2%, 95% CI: 33.3%-35.1%). Detection of more than 1 cell within a cross-sectional scan was strongly suggestive of clinical activity, with an area under the curve of 0.76 (95% CI: 0.62-0.89) for SUN ≥0.5+ and 0.85 (95% CI: 0.73-0.98) for the detection of SUN ≥1+. Cell count correlated with SUN grades at higher levels of inflammation (SUN ≥2+ both protocols, SUN ≥1+ HV-scans). There was an independent positive association between age and AS-OCT cell (adjusted correlation coefficient 0.2 cells for each additional year of age).

CONCLUSIONS

Operator-dependent factors impact the diagnostic and quantification performance of AS-OCT for anterior chamber inflammation. However, the strong, "dose-respondent" correlation of LV protocols with SUN grading promises clinical utility without the storage and analysis burden of HV approaches. Further work will involve exploration of the need for age-specific image metric interpretation.

Reducing the risk of visual disability for children with juvenile idiopathic arthritis uveitis through disease surveillance: past and future challenges

Childhood blindness significantly impacts development, education, employment, and mental health, creating burden for families and society. Between 8% and 30% of children with Juvenile Idiopathic Arthritis (JIA) develop a potentially blinding chronic inflammatory eye disease, uveitis (JIAU). Alongside the use of disease-modifying agents and anti-TNF immunomodulators, JIAU surveillance has helped to reduce the risk of JIAU related blindness.Inconsistent guidance on JIAU surveillance has previously been a hindrance to care delivery and access for professional and families. The Multinational Interdisciplinary Working Group for Uveitis in Childhood (MIWGUC) has brought some much-needed standardisation to JIA surveillance, developing a consensus-based screening proposal which simplifies the protocol, supporting implementation amongst non-specialists, and ensuring that children at risk receive the timely eye examination necessary to avoid life-changing visual disability. In this commentary on the MIWGUC surveillance proposal, we also address the implementation of such surveillance. A global shortage of ophthalmologists threatens the sustainability of these surveillance programs. Innovative approaches could be imaging-based detection. The accessibility of Optical Coherence Tomography (OCT) imaging may make OCT a feasible future option for community-based surveillance, reducing the burden on ophthalmologists, and on patients and their families.

Automated quantification of anterior chamber cells using swept-source anterior segment optical coherence tomography

PURPOSE

To validate automated counts of presumed anterior chamber (AC) cells in eyes with histories of uveitis involving the anterior segment using swept-source (SS) anterior segment optical coherence tomography (AS-OCT) against manual counts and compare automated counts against Standardized Uveitis Nomenclature (SUN) criteria.

METHODS

Eyes were imaged with the ANTERION SS AS-OCT device (Heidelberg Engineering). A fully automated custom algorithm quantified the number of hyper-reflective foci (HRF) in line-scan images. Automated and manual counts were compared using interclass correlation (ICC) and Pearson correlation coefficient. Automated counts were compared to SUN grades using a mixed-effects linear regression model.

RESULTS

90 eyes (54 participants) were included; 67 eyes (41 participants) had histories of uveitis, while 23 eyes (13 healthy participants) served as controls. ICC comparing automated to manual counts was 0.99 and the Pearson correlation coefficient was 0.98. Eyes at each SUN grade with corresponding median HRF (interquartile range [IQR]) were: Grade 0, 42 eyes, 2 HRF (0,4); 0.5+, 10 eyes, 10 HRF (8,15); 1+, 9 eyes, 22 HRF (15,33); 2+, 3 eyes, 27 HRF; 3+, 2 eyes, 128 HRF; 4+, 1 eye, 474 HRF. For every 1-step increase in grade, automated count increased by 38 (p < 0.001) or 293% (Pearson correlation coefficient 0.80, p < 0.001). Automated counts differed significantly between clinically inactive eyes (2 HRF [0,4]) and controls (0 HRF [0,1], p = 0.02).

CONCLUSIONS

Our algorithm accurately counts HRF when compared to manual counts, with strong correlation to SUN clinical grades. SS AS-OCT offers the advantage of imaging of the entire AC and may allow detection of subclinical inflammation in eyes that appear clinically inactive.

The management of adult and paediatric uveitis for rheumatologists

Uveitis encompasses multiple different conditions that are all characterized by intra-ocular inflammation. Uveitis occurs in the context of many different rheumatological conditions and carries a substantial risk to vision. Uveitis can develop both at the early stages of rheumatic diseases, sometimes even preceding other clinical features, and at later stages of disease. Uveitis can also occur as either a direct or an indirect complication of therapies used to treat patients with rheumatic disease. Conversely, patients with uveitis of non-rheumatic aetiology sometimes require immunosuppression, a treatment option that is not readily accessible to ophthalmologists. Thus, collaborative working between rheumatologists and ophthalmologists is critical for optimal management of patients with uveitis. This Review is written with rheumatologists in mind, to assist in the care of patients with uveitis. We collate and summarize the latest evidence and best practice in the diagnosis, management and prognostication of uveitis, including future trends and research priorities.

Diagnosis and Treatment of Uveitis in Children: A Summary of the Latest Data from a 5-Year Literature Review (2018-2023)

Pediatric uveitis has a low incidence. It is very diverse in its presentation and is often the first sign of a severe systemic disease. The pediatric population poses a special therapeutic and diagnostic challenge due to the potentially adverse effects of therapeutic agents on the young body and difficult cooperation with the patient during the examination, as well as the increased risk of complications that can lead to severe disability. The most commonly diagnosed type of uveitis is non-infectious, with first-line therapy consisting of systemic corticosteroids followed by disease-modifying drugs (methotrexate (MTX), mycophenolate mofetil (MMF), and cyclosporin A (CsA)). In severe, refractory cases, biologic therapy is used. The authors reviewed the current literature on the etiology, diagnostic tools, and treatment of uveitis in the pediatric population covering the years 2018-2023, presenting current methods of modern diagnosis and treatment. The reason for writing this article was the need to update the knowledge on uveitis, driven by the increasing prevalence of autoimmune uveitis in the pediatric population. This trend presents significant challenges in diagnosing and treating the disease, as well as managing its complications. Correctly identifying the pathogenetic factor of uveitis can facilitate the diagnosis of the systemic disease underlying the ocular infection and enable the timely implementation of systemic treatment. Furthermore, the emergence of new diagnostic methods necessitates a revision and update of ophthalmic knowledge, essential for both ophthalmologists and other specialists involved in the treatment of uveitis.

Establishing the Normative Data Set Necessary for Imaging-Based Childhood Uveitis Surveillance: A Cross-Sectional Study

Purpose

Anterior segment optical coherence tomography (AS-OCT) is an emerging diagnostic and monitoring tool for anterior uveitis. We investigated AS-OCT findings in the eyes of a large, diverse population of children free of uveitis to establish its potential to "rule out" accurately those without disease.

Methods

In this cross-sectional observational study, image acquisition was performed with swept source AS-OCT (Heidelberg Anterion), using a protocol of 13 B-scans per volume, from 217 children (434 eyes) aged 5 to 15 years, with analysis of acquired images (identification of apparent inflammatory cells, or "cell events") by multiple graders. Outcomes of interest were median and maximum cell event count (MEDCC, MAXCC) per B-scan from each eye and the total cell event count (TCC) per volume scan.

Results

At least one cell event was detected in volume scans of 76% of eyes (329/434) and 87% of children (189/217). The maximum number (MAXCC) per scan ranged from 0 to 6 (median, 2). There was a strong positive association between increasing age (years) and the number of cell events detected within a volume scan following adjustment for gender and iris color (adjusted regression coefficient for TCC 0.5; P < 0.0001; 95% confidence interval, 0.4-0.7).

Conclusions

Our findings demonstrate that apparent inflammatory cells are detectable on AS-OCT in the apparently healthy eyes of children and furthermore suggest early life developmental changes in blood-iris barrier stability that merit further exploration. We provide the foundation for the normative data set necessary for establishing the clinical utility of AS-OCT for surveillance of children with inflammatory eye diseases.

Laser Flare Photometry to Monitor Childhood Chronic Uveitis: A Preliminary Report of a Monocentric Italian Experience

Background: Childhood chronic non-infectious uveitis (cNIU) is a challenging disease that needs close monitoring. Slit lamp evaluation (SLE) is the cornerstone of ophthalmological evaluation for uveitis, but it is affected by interobserver variability and may be problematic in children. Laser flare photometry (LFP), a novel and objective technique, might be used in children with uveitis. Aim: The aim of this study was to attempt the use of LFP in cNIU clinical practice. Methods: Children, attending the Rheumatology Unit and who were scheduled to receive ophthalmological evaluation, were prospectively enrolled to concomitantly receive SLE and LFP. SLE was performed blind to LFP measure. Demographic, laboratory, clinical, and ophthalmology data were collected. Results: A total of 29 children (58 eyes) were enrolled, including 3 with juvenile idiopathic arthritis without uveitis (JIA-no-U), 15 with JIA-associated uveitis (JIA-U), and 11 with idiopathic chronic uveitis (ICU). We observed significantly higher LFP values in the eyes of children with uveitis compared to the others (10.1 IQR 7.1-13.6 versus 6.2 IQR 5.8-6.9, p = 0.007). Accordance between the SLE and LFP measures, at baseline (ρ.498, p < 0.001) and during the follow-up (LFP II ρ 0.460, p < 0.001, LFP III ρ 0.631, p < 0.001, LFP IV ρ 0.547, p = 0.006, LFP V ρ 0.767, p = 0.001), was detected. We evaluated significant correlation between LFP values and the presence of complications (ρ 0.538, p < 0.001), especially with cataract formation (ρ 0.542, p < 0.001). Conclusions: In this cohort, LFP measurements showed a good correlation with SLE. LFP values showed a positive correlation with the presence of complications. LFP might be considered as a reliable objective modality to monitor intraocular inflammation in cNIU.

Anterior chamber inflammation grading methods: A critical review

Assessing anterior chamber inflammation is highly subjective and challenging. Although various grading systems attempt to offer objectivity and standardization, the clinical assessment has high interobserver variability. Traditional techniques, such as laser flare meter and fluorophotometry, are not widely used since they are time-consuming. With the development of optical coherence tomography with high sensitivity, direct imaging offers an excellent alternative to assess objectively inflammation with the potential for automated analysis. We describe various anterior chamber inflammation grading methods and discuss their utility, advantages, and disadvantages.

Challenges and management of childhood non-infectious chronic uveitis

INTRODUCTION

Childhood uveitis is a sight-threatening condition, because if not properly recognized and treated can lead to several ocular complications and blindness. It represents a real challenge not only from an etiologic/diagnostic point of view, but also for management and therapy.

AREAS COVERED

In this review we will discuss the main etiologies, the diagnostic approach, risk factors associated to childhood non-infectious uveitis (cNIU), and the difficulties in eye examination in childhood. Moreover, we will discuss the treatment of cNIU in term of therapeutic choice, timing of initiation and withdrawal.

EXPERT OPINION

Identification of specific diagnosis is mandatory to prevent severe complications, thus a thorough differential diagnosis is essential. Pediatric eye examination may be extremely challenging due to the scarce collaboration, but novel techniques and biomarkers will help in identify low grade of inflammation, eventually modify long-term outcomes. Once identified the appropriate diagnosis, recognition of children who may benefit of a systemic treatment is crucial. What, When and how long are the key questions to address in this field. Current evidence and future results of ongoing clinical trials will help in driving treatment. A proper ocular screening, not only in the context of systemic disease, should be discussed by experts.

Automated Quantitative Analysis of Anterior Segment Inflammation Using Swept-Source Anterior Segment Optical Coherence Tomography: A Pilot Study

Background: The aim of this study is to develop an automated evaluation of anterior chamber (AC) cells in uveitis using anterior segment (AS) optical coherence tomography (OCT) images. Methods: We analyzed AS swept-source (SS)-OCT (CASIA 2) images of 31 patients (51 eyes) with uveitis using image analysis software (Python). An automated algorithm was developed to detect cellular spots corresponding to hyper-reflective spots in the AC, and the correlation with Standardization of Uveitis Nomenclature (SUN) grading AC cells score was evaluated. The approximated AC grading value was calculated based on the logarithmic approximation curve between the number of cellular spots and the SUN grading score. Results: Among 51 eyes, cellular spots were automatically segmented in 48 eyes, whereas three eyes (all SUN grading AC cells score: 4+) with severe fibrin formation in the AC were removed by the automated algorithm. The AC cellular spots increased with an increasing SUN grading score (p < 0.001). The 48 eyes were split into training data (26 eyes) and test data (22 eyes). There was a significant correlation between the SUN grading score and the number of cellular spots in 26 eyes (rho: 0.843, p < 0.001). There was a significant correlation between the SUN grading score and the approximated grading value of 22 eyes based on the logarithmic approximation curve (rho: 0.774, p < 0.001). Leave-one-out cross-validation analysis demonstrated a significant correlation between the SUN grading score and the approximated grading value of 48 eyes (rho: 0.748, p < 0.001). Conclusions: This automated anterior AC cell analysis using AS SS-OCT showed a significant correlation with clinical SUN grading scores and provided SUN AC grading values as a continuous variable. Our findings suggest that automated grading of AC cells could improve the accuracy of a quantitative assessment of AC inflammation using AS-OCT images and allow the objective and rapid evaluation of anterior segment inflammation in uveitis. Further investigations on a large scale are required to validate this quantitative measurement of anterior segment inflammation in uveitic eyes.