Prolonged Cone b-Wave on Electroretinography Is Associated with Severity of Inflammation in Noninfectious Uveitis

Ultrawide-field fluorescein angiography features in patients with anterior uveitis

PURPOSE

To evaluate the utility of ultrawide-field fluorescein angiography (UWFFA) in patients with anterior uveitis by investigating the detection of retinal vascular leakage (RVL) and the subsequent implications on disease diagnosis and management.

STUDY DESIGN/MATERIALS AND METHODS

Patients, who were referred to the National Eye Institute (NEI) for evaluation of anterior uveitis and underwent UWFFA imaging at the initial visit, were included in this study. The electronic medical records of eligible patients were reviewed. The UWFFA images were assessed for severity of retinal vascular leakage, presence of macular leakage, and optic disc leakage by a two-grader system, and intergrader agreement was calculated using the κ-value. Patients with altered diagnoses and management attributable to UWFFA results were noted.

RESULTS

A total of 93 eyes of 63 patients were included in the study. Of 93 eyes, 31 (33.3%) eyes had RVL on UWFFA, with 26 (28.0%) eyes and 5 (5.4%) eyes showing mild and moderate-severe RVL, respectively. Twenty-five (26.9%) eyes showed macular leakage, and 7 (7.5%) eyes showed optic disc leakage. The κ-values ranged from 0.85 - 0.87 indicating excellent intergrader agreement. Of the 31 eyes with RVL, the diagnosis was changed to anterior/intermediate uveitis for 9 (29.0%) eyes and to panuveitis for 4 (12.9%) eyes. Systemic treatment was escalated in 5 patients.

CONCLUSION

Our results suggest that UWFFA imaging is useful in detecting subclinical posterior involvement in patients with anterior uveitis. Moreover, UWFFA results in altered diagnosis and treatment approaches in a portion of patients.

Electroretinographic findings in retinal vasculitis

AIM

To describe and correlate electroretinographic responses with clinical and angiographic findings in retinal vasculitis (RV).

METHODS

Medical records of patients with diagnosis of RV at a tertiary eye centre from December 2017 to May 2021 were reviewed. Cases in which fluorescein angiography (FFA) and full field electroretinography (ffERG) were done within 1 month were included. FFAs were graded according to the Angiography Scoring for Uveitis Working Group from 0 to 40, where 0 is normal. A novel ffERG grading system was implemented where individual waves were graded for timing and amplitude and general ffERG score was determined with 6 being a perfect score.

RESULTS

20 patients (34 eyes) were included. Mean age was 43.9±19.8 years; 70% were female. Median best-corrected visual acuity was 0.8 (0.08-1). Mean FFA score was 12.6±6.5. Median general ffERG score was 5 (0-6). 68% and 91% of eyes had responses with general ffERG scores ≥5 and 4, respectively. Flicker timing was most commonly affected.FFA scores weakly correlated with delayed photopic cone b-wave and flicker timing (p=0.03 and 0.016, respectively). Vitreous haze moderately correlated with delayed cone b-wave timing (p<0.001), delayed flicker timing (p=0.002) and weakly correlated with lower flicker amplitude (p=0.03). Underlying systemic disease was associated with poor ffERG responses.

CONCLUSION

In this study, RV was not frequently associated with severe global retinal dysfunction Higher FFA scores, and vitreous haze grading were weakly, but significantly, correlated with cone-generated ffERG responses.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Efficacy and Safety Evaluation of Mometasone Furoate in Treating Ocular Inflammation

Mometasone furoate (MF) is a medium-potency synthetic glucocorticosteroid with anti-inflammatory, antipruritic, and vasoconstrictive properties. However, its role in the treatment of ocular inflammation has not yet been explored. This work investigated the anti-inflammatory activity of MF in ocular tissues. First, the in vivo safety of the intravitreal (IVT) injection of MF (80, 160, and 240 µg) was evaluated via clinical examination (including the assessment of intraocular pressure), electroretinography (ERG), and histopathology. Second, MF was tested in an experimental model of bacillus Calmette-Guérin (BCG)-induced uveitis in Wistar rats. Intraocular inflammation was then evaluated via a slit-lamp and fundus examination, ERG, histopathology, and the quantification of pro-inflammatory markers. Intravitreal MF showed no toxicity in all the investigated doses, with 160 µg leading to attenuated disease progression and improvement in clinical, morphological, and functional parameters. There was a significant reduction in the levels of inflammatory markers (myeloperoxidase, interleukins 6 and 1β, CXCL-1, and tumor necrosis factor-alpha) when compared to the levels in untreated animals. Therefore, MF should be further investigated as a promising drug for the treatment of ocular inflammation.

Transient Increase of Flicker Electroretinography Amplitudes after Cataract Surgery: Association with Postoperative Inflammation

Purpose

To determine the characteristics and cause of the increase in the amplitude of flicker electroretinography (ERG) after cataract surgery.

Design

Prospective, observational clinical study.

Participants

Thirty patients who underwent cataract surgery.

Methods

Flicker ERGs were recorded with the RETeval system without mydriasis. The central macular thickness (CMT) was measured by OCT and the aqueous flare value (AFV) by laser flare-cell photometry. These examinations were performed before surgery and 1 day, 1 week, 1 month, 2 months, and 3 months after surgery. Linear regression analysis through the origin was used to compare the correlations between the relative changes in flicker ERG amplitudes and the changes in the CMT and AFV at different times after the surgery.

Main Outcome Measures

The amplitude of flicker ERGs, CMT, and AFV.

Results

The mean amplitude of flicker ERGs increased significantly by 31% at 1 week after surgery (P < 0.001); a significant increase in the amplitudes was not present at 3 months after the surgery. The mean AFV was significantly increased at 1 day after surgery (P < 0.001), and the CMT was significantly increased at 1 to 3 months after surgery (P < 0.001). The changes in flicker ERG amplitudes at 1 week after surgery were significantly associated with the changes in the CMT at 1 to 3 months after surgery (P < 0.05), and they were weakly associated with the changes in AFV at 1 day after surgery (P = 0.05).

Conclusions

These results suggest that the increase in the amplitude of flicker ERGs after cataract surgery is a transient phenomenon that has a peak at 1 week after surgery. The increase of flicker ERG amplitude was associated with measures that are frequently used to evaluate postoperative inflammation.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references.

Efficacy and Safety of Immunosuppressant Therapy for Noninfectious Uveitis: A Systematic Review and Meta-Analysis

Objective

To analyze efficacy and safety of immunosuppressant therapy for noninfectious uveitis.

Methods

A network search of PubMed, ResearchGate, and EMBASE databases was conducted for relative literature and studies from the inception of each database to April 2021. Primary outcomes were efficacy and time to treatment failure of immunosuppressant for noninfectious uveitis. Secondary outcome was incidence of adverse events (AEs). Cochrane risk of bias tool was used to assess risk of bias of included studies. Fixed effects model or random effects model was implemented to assess statistical heterogeneity. Subgroup analysis was employed to analyze heterogeneous sources.

Results

Eight studies were deemed eligible for inclusion with a total of 848 patients. Six studies were randomized controlled trials (RCTs). Among them, a single-blind RCT had relatively high measurement bias and performance bias. Immunosuppressant presented favorable efficacy for noninfectious uveitis than placebo, and RR was 1.43 (95% CI: 1.12-1.82). Immunosuppressant for noninfectious uveitis prolonged the time before failure, and HR was 0.43 (95% CI: 0.32-0.54). AEs increased after immunosuppressant was applied. Compared with immunosuppressant, RR of AEs with placebo was 0.88 (95% CI: 0.71-1.08).

Conclusion

Immunosuppressant contributed to controlling progression of noninfectious uveitis to some extent. Compared with placebo, it increased incidence of AEs. More studies with low heterogeneity are warranted for stronger evidence in clinical.

Recognizing differentiating clinical signs of CLN3 disease (Batten disease) at presentation

Purpose

To help differentiate CLN3 (Batten) disease, a devastating childhood metabolic disorder, from the similarly presenting early‐onset Stargardt disease (STGD1). Early clinical identification of children with CLN3 disease is essential for adequate referral, counselling and rehabilitation.

Methods

Medical chart review of 38 children who were referred to a specialized ophthalmological centre because of rapid vision loss. The patients were subsequently diagnosed with either CLN3 disease (18 patients) or early‐onset STGD1 (20 patients).

Results

Both children who were later diagnosed with CLN3 disease, as children who were later diagnosed with early‐onset STGD1, initially presented with visual acuity (VA) loss due to macular dystrophy at 5–10 years of age. VA in CLN3 disease decreased significantly faster than in STGD1 (p = 0.01). Colour vision was often already severely affected in CLN3 disease while unaffected or only mildly affected in STGD1. Optic disc pallor on fundoscopy and an abnormal nerve fibre layer on optical coherence tomography were common in CLN3 disease compared to generally unaffected in STGD1. In CLN3 disease, dark‐adapted (DA) full‐field electroretinogram (ERG) responses were either absent or electronegative. In early‐onset STGD1, DA ERG responses were generally unaffected. None of the STGD1 patients had an electronegative ERG.

Conclusion

Already upon presentation at the ophthalmologist, the retina in CLN3 disease is more extensively and more severely affected compared to the retina in early‐onset STGD1. This results in more rapid VA loss, severe colour vision abnormalities and abnormal DA ERG responses as the main differentiating early clinical features of CLN3 disease.

Electroretinogram abnormalities in non-infectious uveitis often persist

PURPOSE

In uveitis, a prolonged implicit time of the cone b-wave is a characteristic electroretinogram (ERG) abnormality. We investigated whether this can improve or deteriorate over time and which clinical factors are associated with change.

METHODS

Prospective cohort study. Patients with a non-infectious uveitis were included. An ERG was measured in the first year of uveitis onset and a follow-up ERG one year later. Changes in the implicit time of the cone b-wave were investigated in relation to clinical parameters including the following: demographics, uveitis characteristics, treatment, best-corrected visual acuity, optical coherence tomography parameters and fluorescein angiography scores.

RESULTS

Of 98 eyes (63 patients), 40 showed a prolonged cone b-wave on the first ERG, which improved in 10 eyes. Eyes with an improved ERG more often had a panuveitis with initially a higher incidence of cells in the anterior chamber during the first ERG, which resolved at the time of their follow-up ERG. Five of the 58 eyes with a normal first ERG had a deteriorated follow-up ERG. These eyes had more frequently an active uveitis at the time of the follow-up ERG. Of the 78 eyes with a stable cone b-wave, 16 had a quiescent inflammation during follow-up. There were no differences in age or treatment.

CONCLUSION

In most patients with non-infectious uveitis, ERG abnormalities appear to be irreversible, even when the inflammation becomes quiescent. However, some ERGs improved, which was associated with reduction in inflammation of the anterior chamber due to panuveitis. In contrast, a worsened ERG was associated with a persistence of inflammation.

Case of lens-induced uveitis associated with supernormal flicker ERG amplitudes after cataract surgery

PURPOSE

To report our findings in a case of lens fragment-induced uveitis associated with supernormal flicker electroretinograms (ERGs) twenty months after the cataract surgery.

METHODS

This is an observational case report. Full-field flicker ERGs were recorded with the RETeval system. Optical coherence tomography (OCT) and slit-lamp biomicroscopy were used to assess the uveitis during the follow-up period.

RESULTS

A 70-year-old man, who had undergone cataract surgery 20 months earlier, visited our hospital with a complaint of decreased vision in his right eye. Slit-lamp biomicroscopy revealed corneal edema and a lens fragment was detected in the inferior part of the anterior chamber. OCT showed cystoid macular edema, and flicker ERGs showed a marked increase in the amplitude and a delay in the implicit time in the right eye. These abnormalities of the flicker ERGs improved gradually after the removal of lens fragment and application of topical anti-inflammatory medications.

CONCLUSION

Our case of lens-induced uveitis had supernormal flicker ERG amplitudes. Clinicians should be aware that eyes with uveitis can have larger-than-normal ERG amplitudes.

Effects of DTL electrode position on the amplitude and implicit time of the electroretinogram

PURPOSE

This study sought to investigate whether there is an optimal position of the Dawson, Trick, and Litzkow (DTL) electrodes when measuring the full-field electroretinogram (ERG) for monitoring purposes.

METHODS

In 200 uveitis patients, an extended light-adapted (LA) ERG protocol was measured twice, incorporating the International Society for Clinical Electrophysiology of Vision standards. First, a LA ERG was measured with the DTL in the lower lid position (LLP) and thereafter in the fornix position. Differences in amplitudes and implicit times of a-waves, b-waves, and the 30 Hz peak were investigated. Intraclass correlation coefficients (ICCs) as well as coefficients of variation (CoV) were calculated, to assess both reliability and relative variability between the two DTL positions.

RESULTS

Implicit times showed no statistically significant differences between the two DTL positions. As expected, amplitudes at the different stimulus strengths were 1.12-1.19 higher in the LLP, but there were no significant differences in the CoV between the two DTL positions. The ICC was high for the b-wave and 30 Hz flicker response (0.842-0.979), but lower for the a-wave, especially for amplitudes (0.584-0.716).

CONCLUSIONS

For monitoring purposes in patients, we conclude that based on relative variability, no position is preferable above the other. However, because in most diseases amplitudes are decreased, the LLP may be chosen because it yields higher amplitudes. Whatever the choice, it is important to ensure that the DTL position remains stable during an ERG recording.