Scotoma analysis of 10-2 visual field testing with a white target in screening for hydroxychloroquine retinopathy

Classification of Hydroxychloroquine Retinopathy: A Literature Review and Proposal for Revision

Establishing universal standards for the nomenclature and classification of hydroxychloroquine retinopathy is essential. This review summarizes the classifications used for categorizing the patterns of hydroxychloroquine retinopathy and grading its severity in the literature, highlighting the limitations of these classifications based on recent findings. To overcome these limitations, I propose categorizing hydroxychloroquine retinopathy into four categories based on optical coherence tomography (OCT) findings: parafoveal (parafoveal damage only), pericentral (pericentral damage only), combined parafoveal and pericentral (both parafoveal and pericentral damage), and posterior polar (widespread damage over parafoveal, pericentral, and more peripheral areas), with or without foveal involvement. Alternatively, eyes can be categorized simply into parafoveal and pericentral retinopathy based on the most dominant area of damage, rather than the topographic distribution of overall retinal damage. Furthermore, I suggest a five-stage modified version of the current three-stage grading system of disease severity based on fundus autofluorescence (FAF) as follows: 0, no hyperautofluorescence (normal); 1, localized parafoveal or pericentral hyperautofluorescence on FAF; 2, hyperautofluorescence extending greater than 180° around the fovea; 3, combined retinal pigment epithelium (RPE) defects (hypoautofluorescence on FAF) without foveal involvement; and 4, fovea-involving hypoautofluorescence. These classification systems can better address the topographic characteristics of hydroxychloroquine retinopathy using disease patterns and assess the risk of vision-threatening retinopathy by stage, particularly with foveal involvement.

Atypical Presentations of Hydroxychloroquine Retinopathy: A Case Series Study

Background/Objective: Hydroxychloroquine retinopathy, traditionally characterized by parafoveal or pericentral outer retinal damage, is explored for atypical presentations in Asian patients. This challenges conventional beliefs regarding onset, retinopathy pattern, and associated visual field defects. Methods: Ninety-five patients diagnosed with hydroxychloroquine retinopathy at Hanyang University Hospital underwent screening from January 2010 to December 2023. Swept-source optical coherence tomography (SS-OCT), ultra-widefield fundus autofluorescence (UWF-FAF), and automated visual fields (VF) were employed for detailed structural and functional evaluations. Multifocal electroretinography was performed in selected cases requiring additional objective evidence of retinal toxicity. Results: Among 95 patients, 14 (14.7%) exhibited atypical presentations, including very early onset (n = 1), (far) peripheral-dominant damages (n = 4), perivascular involvement (n = 1), bitemporal hemianopsia due to nasal extensive lesions (n = 1), unilateral involvement (n = 2), and asymmetric involvement in retinopathy pattern or severity between the eyes (n = 7). These findings underscore the importance of utilizing expanded imaging techniques, such as ultra-widefield FAF imaging, to identify atypical presentations of retinal involvement. Conclusions: Screening physicians should consider these atypical presentations to ensure timely diagnosis and appropriate management in patients undergoing hydroxychloroquine treatment.

New proposal for a multimodal imaging approach for the subclinical detection of hydroxychloroquine-induced retinal toxicity in patients with systemic lupus erythematosus

OBJECTIVE

To compare multimodal structural and functional diagnostic methods in patients with systemic lupus erythematosus (SLE) treated with hydroxychloroquine, to identify the best complementary approach for detecting subclinical retinal toxicity.

METHODS

A cross-sectional, unicentric study was conducted on patients with SLE treated with hydroxychloroquine. Each patient underwent a comprehensive ophthalmic evaluation, comprising structural tests (spectral-domain optical coherence tomography (SD-OCT), en face OCT, en face OCT angiography (OCTA), fundus autofluorescence (FAF)) and functional tests (automated perimetry for visual field (VF) testing, multifocal electroretinography (mfERG)). A diagnosis of macular toxicity required the presence of abnormalities in at least one structural and functional test. The Kappa Concordance Index was used to assess the concordance among the different tests in detecting potential macular toxicity-associated alterations.

RESULTS

Sixty-six patients with SLE (132 eyes) were consecutively enrolled. Four (6.1%) patients developed subclinical hydroxychloroquine-induced retinal toxicity without visual acuity impairment. The proportion of abnormal results was 24% for both en face OCT and en face OCTA. Regarding functional analysis, VF was less specific than mfERG in detecting subclinical retinal toxicity (VF specificity 47.5%). En face OCT and en face OCTA structural findings showed better concordance, with a kappa index >0.8, and both identified the same cases of toxicity as FAF.

CONCLUSION

Although structural OCT and VF are frequently used to screen for hydroxychloroquine-induced retinal toxicity, our findings suggest that a combination of mfERG, en face OCT and en face OCTA could improve the diagnostic accuracy for subclinical retinal damage. This study emphasises the importance of a multimodal imaging strategy to promptly detect signs of hydroxychloroquine-induced retinal toxicity.

Visual field examinations using different strategies in Asian patients taking hydroxychloroquine

In this study, we investigated the patterns of visual field (VF) defects and the diagnostic abilities of VF tests using different strategies in Asian patients with hydroxychloroquine retinopathy. Patients screened for hydroxychloroquine retinopathy using optical coherence tomography, fundus autofluorescence, VF, and/or multifocal electroretinography were included. The VF was performed using the Humphrey 30-2 and/or 10-2 strategy, and 2,107 eyes of 1,078 patients with reliable results, including 136 eyes of 68 patients with hydroxychloroquine retinopathy, were analyzed. The characteristics of VF findings were evaluated and the sensitivity and specificity were compared between the 30-2 and 10-2 tests in subgroups of retinopathy severity and pattern. The most common VF defect pattern was partial- or full-ring scotoma in both the 10-2 and 30-2 tests. Among the eyes with hydroxychloroquine retinopathy that underwent both tests, 14.2% showed a disparity between the two tests, almost all at the early stage. In overall and early pericentral retinopathy, the sensitivity of the 30-2 test was significantly higher than that of the 10-2 test (95.7% vs. 77.1% and 90.6% vs. 53.1%, respectively; P < 0.05). However, the specificity of the 10-2 test was significantly higher than that of the 30-2 test (89.6% vs. 84.8%, P < 0.001). Therefore, the pattern of retinopathy should be carefully considered when choosing a VF strategy for better detection of hydroxychloroquine retinopathy.

Systemic toxicity of chloroquine and hydroxychloroquine: prevalence, mechanisms, risk factors, prognostic and screening possibilities

Chloroquine (CQ) and its hydroxylated analog, hydroxychloroquine (HCQ), are 4-aminoquinoline initially used as an antimalarial treatment. CQ and HCQ (4-aminoquinoline, 4-AQ) are today used in rheumatology, especially to treat rheumatoid arthritis and systemic lupus erythematosus. Their mechanism of action revolves around a singular triptych: 4-AQ acts as alkalizing agents, ionized amphiphilic molecules, and by binding to numerous targets. 4-AQ have so pleiotropic and original mechanisms of action, providing them an effect at the heart of the regulation of several physiological functions. However, this broad spectrum of action is also at the origin of various and original side effects, notably a remarkable chronic systemic toxicity. We describe here the 4-AQ-induced lesions on the eye, the heart, muscle, the nerves, the inner ear, and the kidney. We also describe their prevalence, their pathophysiological mechanisms, their risk factors, their potential severity, and the means to detect them early. Most of these side effects are reversible if treatment is stopped promptly. This 4-AQ-induced toxicity must be known to prescribing physicians, to closely monitor its appearance and stop treatment in time if necessary.

Prevalence of hydroxychloroquine retinopathy with long-term use in a cohort of Indian patients with rheumatic diseases

The study aims to estimate the prevalence of hydroxychloroquine (HCQ) retinopathy in a cohort of Indian patients and analyse the associated factors. Adult patients with rheumatological disorders aged ≥ 18 years using HCQ for more than 5 years and/or having received a cumulative dose > 400 g were included. Demographic and clinical data were collected and all underwent ophthalmological tests which included Humphrey automated visual fields (AVF) and spectral domain optical coherence tomography (SD-OCT). The various clinical characteristics of the patients were compared. The study included 110 patients with a mean age of 43.5 ± 10.1 years and predominantly females. Eleven patients (10%) were diagnosed with definite HCQ retinopathy. The mean daily dose of HCQ (mg/kg of real body weight) was significantly different in the groups with and without retinopathy (5.7 ± 0.9 vs 5.1 ± 0.8, p = 0.04). Patients with retinopathy had significantly more colour vision abnormalities (odds of 16.9; confidence interval 4.1-69.1, p = 0.0001) and higher prevalence of both parafoveal and perifoveal thinning (p < 0.0001). Age, gender, duration of HCQ use, cumulative HCQ dose and body mass index were not found to be associated with retinopathy. Four out of 11 patients had abnormalities only on 30-2 protocol for AVF testing, two had abnormalities only on 10-2 protocol, whereas five patients had abnormalities on both protocols. SD-OCT abnormalities were present in all patients with retinopathy. Hydroxychloroquine retinopathy was prevalent in the study cohort and significantly associated with a higher daily dose of HCQ (mg/kg real body weight).

Hydroxychloroquine retinopathy

Hydroxychloroquine (HCQ; Plaquenil) is used increasingly in the management of a variety of autoimmune disorders, with well established roles in dermatology and rheumatology and emerging roles in oncology. Hydroxychloroquine has demonstrated a survival benefit in patients with systemic lupus erythematosus; some clinicians advocate its use in all such patients. However, Hydroxychloroquine and chloroquine (CQ) have been associated with irreversible visual loss due to retinal toxicity. Hydroxychloroquine retinal toxicity is far more common than previously considered; an overall prevalence of 7.5% was identified in patients taking HCQ for greater than 5 years, rising to almost 20% after 20 years of treatment. This review aims to provide an update on HCQ/CQ retinopathy. We summarise emerging treatment indications and evidence of efficacy in systemic disease, risk factors for retinopathy, prevalence among HCQ users, diagnostic tests, and management of HCQ retinopathy. We highlight emerging risk factors such as tamoxifen use, and new guidance on safe dosing, reversing the previous recommendation to use ideal body weight, rather than actual body weight. We summarise uncertainties and the recommendations made by existing HCQ screening programmes. Asian patients with HCQ retinopathy may demonstrate an extramacular or pericentral pattern of disease; visual field testing and retinal imaging should include a wider field for screening in this group. HCQ is generally safe and effective for the treatment of systemic disease but because of the risk of HCQ retinal toxicity, modern screening methods and ideal dosing should be implemented. Guidelines regarding optimal dosing and screening regarding HCQ need to be more widely disseminated.

Retinal Toxicity in Patients Treated With Hydroxychloroquine: A Cross-Sectional Study

Hydroxychloroquine (HCQ) is an antimalarial medication that can also be used to treat autoimmune diseases. However, it can produce irreversible changes to the retina that lead to visual impairment. The aim of this study was to determine the proportion of patients treated with HCQ who develop retinal toxicity and the risk factors for the development of HCQ-induced retinal toxicity among Iranian patients. The is a cross-sectional clinical study of 59 patients who were treated with HCQ during 2014-2015. A questionnaire was used to collect data on the following demographic and clinical factors: age, gender, type of rheumatic disease, history of cataract surgery, daily and cumulative HCQ dose, and duration of HCQ use. Retinal toxicity was diagnosed on the basis of the automated perimetry results of the central 10° of vision and spectral domain optical coherence tomography. The associations between the demographic and clinical factors and retinal toxicity were assessed, and P < 0.05 was considered statistically significant. Retinal toxicity was detected in 18 (30.5%) of the patients, and 5 (8.5 %) developed color vision impairments. There was no association between retinal toxicity and sex (P = 0.514), history of cataract surgery (P = 0.479), type of rheumatic disease (P = 0.539), or daily HCQ dose (P = 0.062). However, there was a significant positive association between retinal toxicity and age (P = 0.006), cumulative HCQ dose (P = 0.002), and duration of HCQ use (P < 0.001). In conclusion, the risk factors for retinal toxicity after HCQ treatment were advanced age, use of a higher cumulative HCQ dose, and a longer duration of treatment.

Scotoma analysis of 10-2 visual field testing with a red target in screening for hydroxychloroquine retinopathy

Objective

To quantify the variability of scotomas detected by 10–2 visual field (VF) testing with a red target in patients taking hydroxychloroquine without and with retinopathy.

Design

Retrospective review of clinical charts and VFs.

Methods

Twenty-four patients taking hydroxychloroquine without retinopathy, and eight patients taking hydroxychloroquine with retinopathy were tested in this study. Retinopathy was defined by annular scotomas on 10–2 VF testing with corroborative spectral domain optical coherence tomographic outer retinal changes and multifocal electroretinographic changes leading to cessation of hydroxychloroquine or chloroquine. Location and depth of scotoma points on 10–2 VF testing were recorded and their fates followed in serial, reliable 10–2 VFs performed with a red target over time. The main outcome measures for this study were the number of scotoma points and locations, percentage of persistent scotoma points, size of scotomas, location of scotomas, and percentage of scotomas deepening.

Results

A median of 3, interquartile range (IQR) (2, 5), scotoma points per VF occurred in patients without retinopathy. A median of 86%, IQR (77, 100), of these resolved on the subsequent field. For patients with retinopathy, a median of 50%, IQR (46, 79), resolved, a difference compared to patients without retinopathy that was significant (P=0.0158). The median percentage of scotoma points in the zone from 2° to 8° from fixation in eyes with retinopathy was 72%, IQR (54, 100), compared to 49%, IQR (40, 54), in eyes without retinopathy (P=0.0069). The number of persistent scotoma locations at the last visit was higher in eyes with retinopathy: 3, IQR (1, 3), versus 0, IQR (0, 1), in patients without retinopathy, P=0.0156.

Conclusion

Point scotomas are common and variable in 10–2 VF testing with a red target for hydroxychloroquine retinopathy in subjects without retinopathy. Scotoma points in eyes with retinopathy are less variable. The annular zone 2°–8° from fixation was useful for distinguishing the significance of scotoma points. Discriminating eyes with retinopathy from eyes without retinopathy is probably easier using the 10–2 VF with a white target than a red target.