Agreements between 24-2 and 24-2C Test Grids for Chloroquine/Hydroxychloroquine Retinopathy Patients and High-Risk Patients

Agreements between 24-2 and 24-2C Test Grids for Chloroquine/Hydroxychloroquine Retinopathy Patients and High-Risk Patients | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Agreements between 24-2 and 24-2C Test Grids for Chloroquine/Hydroxychloroquine Retinopathy Patients and High-Risk Patients Kitiya Ratanawongphaibul, Chananchida Wongwachira, Disorn Suwajanakorn, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6769459/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 05 May, 2026 Read the published version in Eye → Version 1 posted 7 You are reading this latest preprint version Abstract Purpose To compare the SITA Standard 24-2 and SITA Faster 24-2C tests in patients with chloroquine/hydroxychloroquine (CQ/HCQ) retinopathy and those at high risk. Methods A prospective, cross-sectional study of 75 participants who underwent CQ/HCQ retinopathy screening using the SITA Standard 24-2, SITA Faster 24-2C, optical coherence tomography, fundus autofluorescence, and a dilated eye examination on the same day. Participants were categorized into retinopathy and non-retinopathy groups by graders. The agreement between the two visual field (VF) tests was assessed using Bland-Altman plots. Results Among the 75 participants, 26 (34.67%) were diagnosed with CQ/HCQ retinopathy. Bland-Altman plots show good agreement in median deviation (MD), pattern standard deviation (PSD) and central mean sensitivity (CMS) between tests. The concordance coefficient wasat 0.89-0.93. Significant differences in MD, PSD, and CMS, were observed between the retinopathy and non-retinopathy groups for both VF tests (P<0.048). However, within each group, the results of both VF tests were comparable across all parameters (P=0.08-0.98), except for PSD in the retinopathy group. The SITA Faster 24-2C test had a significantly shorter testing duration. Conclusions The SITA Standard 24-2 and SITA Faster 24-2C tests showed similar efficacy and strongly positive agreement in screening for CQ/HCQ retinopathy. However, the SITA Faster 24-2C minimized the testing time. The addition of testing points within the central 10-degree field did not enhance the detection of CQ/HCQ retinopathy in the Thai population Health sciences/Diseases/Eye diseases/Retinal diseases Health sciences/Medical research/Outcomes research Health sciences/Health care/Diagnosis/Physical examination Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 INTRODUCTION Chloroquine (CQ) and Hydroxychloroquine (HCQ) are commonly used in the treatment of autoimmune diseases, notably systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). 1 Their widespread use is attributed to their favorable safety profiles and minimal physical side effects. However, it is important to acknowledge that their adverse effects can lead to incurable retinopathy. The prevalence of CQ/HCQ retinopathy stands at 7.5% within 5 years and escalates to 20% after 20 years of continuous CQ/HCQ administration. 2 Key risk factors associated with retinopathy include dosages exceeding 2.3 mg/kg for CQ and 5 mg/kg for HCQ, prolonged usage surpassing 5 years, renal impairment, concurrent usage with tamoxifen, and a history of prior retinopathy. Concomitantly, minor risk factors are advanced age, hepatic, and hereditary conditions. 3 Furthermore, CQ/HCQ retinopathy continues to progress even after discontinuation of the drug. Therefore, early CQ/HCQ retinopathy detection is essential for effectively preventing irreversible retinopathy. Automated visual field (VF) testing, together with spectral domain optical coherence tomography (SD-OCT), constitutes one of the fundamental diagnostic tools for the detection of CQ/HCQ retinopathy. In accordance with the recommendations provided by the American Academy of Ophthalmology in 2016, 3 fundus autofluorescence (FAF) and multifocal electroretinography (mfERG) also play a significant role in diagnosing this condition. Moreover, the guidelines suggest the use of a broader VF test, such as the 24 − 2 or 30 − 2, for individuals of Asian descent, as opposed to the 10 − 2 test commonly employed for Caucasians. This recommendation is grounded in research indicating that 50% of Asians frequently exhibit VF defects at distances exceeding 8 degrees from the fovea. 4 In contrast, a 2019 study conducted in Thailand revealed that up to 70% of HCQ retinopathy cases manifest VF defects in parafoveal areas (2–7 degrees from the fovea). 5 Consequently, employing a wide VF test spanning 24 or 30 degrees, which assesses the parafoveal region with only four points, may miss certain patients. The study further underscores that 12% of glaucoma patients, who exhibit retinopathy detected through a 10 − 2 or 10-degree VF test and SD-OCT, may not exhibit irregularities in the 24 − 2 VF test. 6 The Humphrey VF Swedish Interactive Threshold Algorithm (SITA) Faster 24-2C (Carl Zeiss Meditec, Germany) was developed in 2019 with the specific aim of enhancing sensitivity for detecting glaucoma. 7 This was achieved by incorporating an additional 10 test points within the central 10-degree radius. Additionally, a faster algorithm was implemented to reduce test duration. A recent study has shown that SITA Faster 24-2C exhibits a correlation with VF parameters when compared to the 10 − 2 test in both glaucoma and neuro-ophthalmological patients. 8 This suggests that the 24-2C test is capable of detecting abnormalities that are also identified by the 10 − 2 test. However, there is currently no existing study that specifically examines the utility of the 24-2C test in the context of CQ/HCQ retinopathy. Therefore, the primary objective of this study is to evaluate the agreements between SITA Faster 24-2C as compared to SITA Standard 24 − 2 for the screening of CQ/HCQ retinopathy within the Thai population. METHODS Study Design and Population This prospective cross-sectional study received approval from the Institutional Review Board of the Faculty of Medicine, Chulalongkorn University under IRB number 0172/65. It was registered with the Thai Clinical Trials Registry (TCTR) under the number TCTR20231019002. The research adhered to the principles of the Declaration of Helsinki and was financially supported by the Ratchadapiseksumpotch Fund for Graduate Affairs, Faculty of Medicine, Chulalongkorn University, under Grant number GA65/54. Informed consent was obtained from all study participants following IRB approval. The eligible study participants included patients diagnosed with CQ/HCQ retinopathy and those classified as high-risk patients based on meeting one or more of the following criteria: a CQ dosage exceeding 2.3 mg/kg of real weight, an HCQ dosage exceeding 5 mg/kg of real weight, prolonged usage beyond 5 years, the presence of kidney disease with a subnormal glomerular filtration rate, or concurrent use of tamoxifen. Participants were also required to be 18 years of age or older and possess a documented history of reliable automated perimetry. These eligible participants were recruited from the ophthalmology clinic at King Chulalongkorn Memorial Hospital. The exclusion criteria encompassed individuals exhibiting unreliable VF tests, which were defined as having a fixation loss greater than 20% or false positives exceeding 15%. Furthermore, individuals with suboptimal quality SD-OCT (quality score of less than 15 from SPECTRALIS® OCT), FAF images, as well as those affected by other ocular conditions, such as alternative causes of retinopathy, optic neuropathy, or optical media opacities that could potentially influence perimetry results, were excluded from the study. Patients with contraindications for pupil dilatation were also deemed ineligible. In this study, one eye per patient was considered, focusing on the eye affected by CQ/HCQ retinopathy. In cases of bilateral disease or the non-retinopathy group, the right eye was prioritized unless it exhibited unreliable VF results or suboptimal imaging quality. Clinical Examination & Diagnosis Each patient underwent a VF test using both SITA Standard 24 − 2 and SITA Faster 24-2C of Humphrey visual field analyzer (Carl Zeiss Meditec, Germany), administered in a randomized order by computerized random generator, with a 15-minute interval between tests. This investigation was followed by fundus photography and FAF imaging by CLARUS™ 500 (Carl Zeiss Meditec, Germany), and SD-OCT by SPECTRALIS® (Heidelberg Engineering Inc., USA) under dilated pupils. All tests were performed on the same day by one experienced technician using identical equipment throughout the study. In the following, a comprehensive eye examination was conducted by an ophthalmologist (K.R.), who remained blinded to the patients' medical histories, to assess for other ocular conditions that could potentially impact the VF, SD-OCT, and FAF. All reliable SITA Standard 24 − 2 test results were forwarded to two glaucoma specialists (K.R. and S.C.) for interpretation to determine the presence of CQ/HCQ retinopathy based on expert opinions and the VF criteria of CQ/HCQ retinopathy, which present as a reduction in VF sensitivity, such as a small central defect on the pattern deviation where one or more of the four central points around fixation had a probability of < 1%. 9 In cases where there was a discrepancy in their interpretations, a third glaucoma specialist (A.M.) provided the final judgment. Similarly, SD-OCT and FAF results were transmitted to and interpreted by two retina specialists (D.S. and W.C.). The interpretations were primarily based on expert opinions and commonly reported findings. These included subtle changes in SD-OCT indicative of early toxicity, distinct thinning of the outer retina near the fovea resembling a ‘flying saucer’ shape, and hyperfluorescence around the fovea in cases of moderate toxicity. In severe toxicity, extensive thinning beyond the fovea obscured the bull’s-eye pattern, with additional widespread hyperfluorescence, RPE disruption, and evidence of RPE cell loss observed. 10 If disagreements between the initial two specialists remained unresolved, a third specialist (P.F.) was consulted to provide a final assessment. The diagnosis of CQ/HCQ retinopathy was primarily based on the SITA Standard 24 − 2 test, as delineated in Fig. 1 . In the case where abnormalities suggestive of CQ/HCQ retinopathy were identified using the SITA Standard 24 − 2 test and were further supported findings in SD-OCT or FAF images, a diagnosis of CQ/HCQ retinopathy was confirmed. In instances where VF defects were observed without concurrent structural evidence, mfERG showing amplitude reduction or delayed implicit time was used to confirm central macular dysfunction. 11 In the case of a normal VF, patients will be categorized into the high-risk CQ/HCQ retinopathy (non-retinopathy group). Additionally, those with abnormal VF but without structural defects and normal signals in mfERG will also be classified as part of the non-retinopathy group. Finally, the agreements between SITA Faster 24-2C and SITA Standard 24 − 2 in terms of mean deviation (MD), pattern standard deviation (PSD), and central mean sensitivity (CMS), and the number of flagged pattern deviation points at P < 1% in central 10 degree were assessed for retinopathy and non-retinopathy group separately. Statistical Analysis The sample size for this study was calculated as 75 eyes, based on intraclass correlation coefficient estimation at 0.75 expected reliability, 95% confidence interval of 0.1 precision, and an expected dropout rate of 10%. We used descriptive statistics to assess the demographic data of the groups. The Wilcoxon rank sum tests were used to compare data between retinopathy and non-retinopathy groups. The Wilcoxon signed-rank test was used to compare data between SITA Faster 24-2C and SITA Standard 24 − 2. The Bland-Altman plot and Concordance Correlation Coefficient (CCC) were used to assess agreement between the SITA Standard 24 − 2 and SITA Faster 24-2C tests. The 95% limits of agreement (LoA) shown in the Bland-Altman plot are defined as the mean difference ± 1.96 standard deviations. Statistical analysis was performed using the STATA version 18.0 (StataCorp LLC, Texas, USA). A P-value of 0.05 was considered statistically significant. RESULTS A total of 85 participants were initially recruited for this study. However, 10 participants (11.8%) were subsequently excluded due to unreliable visual fields, and other ocular diseases affecting visual field tests. Among the remaining 75 participants, 26 were classified into the retinopathy group and 49 into the non-retinopathy group based on the specified criteria (Fig. 1 ). Table 1 presents the demographic characteristics. The median age was 51.5 years in the retinopathy group and 45 years in the non-retinopathy group, with a predominance of females. The median weight was 55 kg in the retinopathy group and 53 kg in the non-retinopathy group. Most patients in both groups were treated with HCQ, with SLE being the primary indication for treatment. However, RA was more common in the retinopathy group. The median treatment duration was 9 years for both groups. Kidney involvement was more common in the non-retinopathy group, while liver involvement was rare across both groups. Table 1 Baseline Demographics of Study Patients Characteristics Retinopathy (N = 26) Non-retinopathy (N = 49) P-value † Age, years (median [IQR]) 51.5 (42–46) 45 (34–55) 0.11 Female, n (%) 25 (96.2) 43 (87.8) 0.41 Weight, kg (median [IQR]) 55 (55–70) 53 (48–61) 0.13 CQ/HCQ uses, n (%) 0.07 HCQ 18 (69.2) 36 (73.5) CQ 8 (30.8) 13 (26.5) Dose per day, mg (median [IQR]) HCQ 200 (200–200) 200 (200–200) 0.26 CQ 250 (250–250) 250 (250–250) 0.34 Indication of CQ/HCQ usage, n (%) 0.03* SLE 14 (53.9) 40 (81.6) RA 8 (30.8) 5 (10.2) Others 4 (15.4) 4 (8.2) Duration of CQ/HCQ usage, years (median [IQR]) 9 (5–16) 9 (7-12.5) 0.73 Concomitant disease, n (%) Kidney disease 8 (30.8) 30 (61.2) 0.01* Liver disease 1 (3.9) 0 (0) 0.35 CQ indicates chloroquine; HCQ, hydroxychloroquine; SLE, systemic lupus erythematosus; RA, rheumatoid arthritis The data was reported as median (IQR) for continuous variables and frequency count (%) for categorical variables. † P-values obtained using Wilcoxon rank sum test and Chi square test for comparing data between retinopathy and non-retinopathy group * Statistically significant P-value < .05 In accordance with the diagram illustrated in Fig. 2 , among 26 individuals in the retinopathy group, 16 presented with abnormal visual field test results but showed no structural defects in either SD-OCT or FAF. Subsequently, they were diagnosed with a reduced foveal signal amplitudes in the mfERG, as illustrated by a representative case in Fig. 3 . The remaining 10 patients exhibited abnormalities in both visual field tests and structural defects, which were identified through either SD-OCT, FAF, or both (Fig. 2 ). A total of 26 patients diagnosed with CQ/HCQ retinopathy presented varying lesions in specific retinal areas: 10 cases (38.5%) exhibited parafoveal changes (2–6 degrees from the fovea), 12 cases (46.1%) displayed pericentral alterations (outside 8 degrees from the fovea), and a mixed pattern was observed in 4 cases (15.4%), as depicted in Fig. 4 through VF testing, SD-OCT, or FAF. Among the patients with a pericentral pattern, 83% (10 out of 12) were diagnosed with retinopathy without abnormalities detected in either SD-OCT or FAF. Regards to VF parameters, including MD, PSD, and CMS values, statistically significant differences were observed between the retinopathy and non-retinopathy groups in both VF tests (SITA Faster 24-2C and SITA Standard 24 − 2; P < 0.048), except for the number of flagged pattern deviation points at P < 1% in central 10 degree, where no statistically significant difference was observed when testing with SITA Faster 24-2C (P = 0.09), as presented in Table 2 . However, within each group, their results were comparable across all VF parameters between the two tests (P = 0.08–0.98) except for PSD in the retinopathy group (1.73 dB in SITA Faster 24-2C versus 2.14 dB in SITA Standard 24 − 2; P = 0.02). Additionally, Fig. 5 indicates that both VF tests exhibited a strong positive correlation in terms of MD, PSD, and CMS values, with a coefficient ranging from 0.89 to 0.93. The testing duration for SITA Faster 24-2C was significantly shorter than for SITA Standard 24 − 2 (2.2 minutes versus 4.5 minutes; P < 0.001). Table 2 Comparison of Visual Field Parameters Between Retinopathy and Non-Retinopathy Groups Using SITA Faster 24-2C and SITA Standard 24 − 2 Retinopathy (N = 26) Non-Retinopathy (N = 49) P-value †† Median (IQR) P-value † Median (IQR) P-value † Mean deviation (dB) • SITA faster 24-2C -1.89 (-3.63 to -0.72) 0.34 -0.97 (-2.22 to -0.30) 0.08 0.04* • SITA standard 24 − 2 -1.70 (-3.70 to -0.54) -0.96 (-1.99 to 0.21) 0.02* Pattern standard deviation (dB) • SITA faster 24-2C 1.73 (1.41–2.79) 0.02* 1.50 (1.29–1.76) 0.12 0.048* • SITA standard 24 − 2 2.14 (1.81–2.81) 1.49 (1.37–1.79) < 0.001* Central mean sensitivity (dB) • SITA faster 24-2C 31.2 (28.7–32.4) 0.98 32.4 (31.5–33.0) 0.29 0.001* • SITA standard 24 − 2 31.1 (28.0-31.9) 32.2 (31.0–33.0) 0.001* The number of flagged pattern deviation points at P < 1% in central 10 degree • SITA faster 24-2C 0 (0–3) 0.76 0 (0–1) 0.20 0.09 • SITA standard 24 − 2 1 (1–5) 0 (0–0) < 0.001* The data was reported as median (IQR) for continuous variables. † P-values obtained using Wilcoxon signed-rank test for comparing continuous data between SITA faster 24-2C and SITA standard 24 − 2 †† P-values obtained using Wilcoxon rank sum test for comparing continuous data between retinopathy and non-retinopathy groups * Statistically significant P-value < .05 Table 2 shows that two missing patients who did not undergo mfERG were categorized as part of the non-retinopathy group due to incomplete criteria. However, to prevent unintentional bias, we conducted an additional analysis in which these patients were classified as part of the retinopathy group. The results indicate no significant difference between the two analyses, except for the number of flagged pattern deviation points at P < 1% in the central 10 degrees of the SITA Faster 24-2C test, where a significant difference was observed between the retinopathy and non-retinopathy groups (P = 0.02). (Supplementary Table 1) DISCUSSION Our study found that both the SITA Faster 24-2C and SITA Standard 24 − 2 are effective in detecting CQ/HCQ retinopathy, showing strong correlations between MD, PSD, and CMS across VF tests. However, the 24-2C test offers the benefit of a shorter test duration and demonstrates a significantly lower PSD in retinopathy cases. In Asian populations, CQ/HCQ-induced retinopathy manifests in pericentral, parafoveal, or combined patterns, with reduced CMS confirming parafoveal involvement. Monitoring within a 6-degree radius from the fovea is crucial. For pericentral patterns, utilizing wide-field SD-OCT may improve screening accuracy by detecting changes that standard SD-OCT could miss. The performance of the SITA Faster 24-2C test grid, compared to the SITA Standard 24 − 2 test, demonstrates comparable results in detecting CQ/HCQ retinopathy (Table 2 ). In addition, our study revealed that both SITA Faster 24-2C and SITA Standard 24 − 2 tests exhibited statistically significant reductions in MD and CMS values, as well as increases in PSD in the retinopathy group compared to the non-retinopathy group (Table 2 , P < 0.048). This finding is similar to the previous study that observed comparable VF indices between 24 − 2 and 24-2C in individuals with glaucoma and those suspected of having glaucoma. 12 , 13 These noted deteriorations in these parameters underscore the importance of VF testing in helping clinicians identify suspected cases of CQ/HCQ retinopathy. There is good reliability and consistency of both SITA Faster 24-2C and the SITA Standard 24 − 2 in detecting CQ/HCQ retinopathy (Fig. 5 ). Bland-Altman plots were used to demonstrate agreement and the magnitude of differences between algorithms to avoid the misleading effects of correlation coefficients alone. 14 The results not only reported a strong positive correlation exists between the two VF tests in terms of MD, PSD, and CMS, but Bland-Altman plots also showed good agreement between tests (Fig. 5 ), which is similar to prior studies 15 , 16 . The 95% limits of agreement for mean deviation (MD) between the two strategies ranged from − 2.7 to + 2.3 dB, indicating that the difference in MD between 24-2C and 24 − 2 did not exceed 2.7 dB in either direction in 95% of cases. Such variability is consistent with known test-retest fluctuations in visual field testing and remains within clinically acceptable limits. This interpretation is supported by a large-scale study by Choi et al. 17 , which reported a mean absolute MD difference of 1.7 dB and an intraclass correlation coefficient (ICC) of 0.92 between the first and retest MD measurements using the SITA Standard 24 − 2. In that study, when the baseline MD was approximately − 2 dB, the retest values varied widely, ranging from nearly 0 dB to worse than − 5 dB. This indicates that fluctuations exceeding 2.7 dB can occur within a single test–retest pair, supporting the notion that the observed inter-strategy difference remains within expected physiological variability. There were no statistically significant differences in any parameters, including MD, PSD, CMS, and the number of flagged pattern deviation points with P < 1% within the central 10 degrees between the SITA Standard 24 − 2 and SITA Faster 24-2C in the non-retinopathy group. However, in the retinopathy group, a statistically significant lower or better PSD was observed in the 24-2C test compared to the 24 − 2 test (1.73 dB vs. 2.14 dB, P = 0.02, Table 2 ). While this difference is statistically significant, it may not necessarily indicate a clinically meaningful difference. PSD is influenced by several factors beyond retinal pathology, including fixation stability 18 location and extent of visual field defect, severity of diseases, and algorithm strategies. Additionally, Medeiros et al. reported that perimetry-naive individuals exhibited lower PSD values when tested with the SITA Faster 24-2C strategy compared to the SITA Standard 24 − 2 strategy (1.75 ± 0.80 dB vs. 2.15 ± 1.25 dB, P = 0.016), 15 which is consistent with the findings of our study. Therefore, while statistically significant, the difference in PSD between the two strategies in our study may reflect intrinsic differences in algorithm design rather than true disparities in disease detection. When using SITA Standard 24 − 2 strategy, the number of flagged pattern deviation points at P < 1% within the central 10 degrees was significantly higher in the retinopathy group compared to the non-retinopathy group (P < 0.001). In contrast, the SITA Faster 24-2C strategy showed only a marginally significant difference (P = 0.09). This finding is consistent with previous studies involving patients with glaucoma and glaucoma suspects, which also reported a slightly higher number of test points showing significant depression at P < 1% on the pattern deviation plot when using the SITA Standard 24 − 2 strategy compared to SITA Faster 24-2. 16 However, in our study, no statistically significant differences were observed between the two strategies across comparisons (P = 0.20–0.76; Table 2 ). These findings suggest that although the SITA Faster 24-2C provides additional central test points, it does not enhance the detection of visual field defects in the screening of HCQ retinopathy. This result may be due to two reasons: 1) the prevalence of more pericentral CQ/HCQ retinopathy patterns in Asians, 3 , 4 which may not benefit from adding 10 central points using SITA Faster 24-2C; and 2) The locations of these additional points, areas more susceptible to glaucomatous damage in the ganglion cell layer and retinal nerve fiber layer, may not effectively represent the early changes of CQ/HCQ retinopathy, which primarily affects the outer retinal layer and photoreceptors. 19 Our analysis focused on the central 10-degree region, where the structural differences between the two test strategies are most evident. The SITA Faster 24-2C includes 10 additional central test points that are not present in the SITA Standard 24 − 2. Outside this region, both strategies have identical test point locations and densities. Therefore, limiting the analysis to the central 10 degrees provides the most meaningful basis for comparison and highlights the specific contribution of the additional test points introduced in the 24-2C strategy. In relation to VF damage in CQ/HCQ retinopathy, not only do pericentral lesions occur, but parafoveal lesions are also observed in the Asian population. Our study found a reduction in CMS within a 10-degree radius in both the 24 − 2 and 24-2C tests among the CQ/HCQ retinopathy group. Additionally, SD-OCT revealed parafoveal patterns in 38.5% of cases, and mixed patterns (both pericentral and parafoveal lesions) in 15.4% of cases. These findings provide confirmed evidence of parafoveal lesions in Asians. Our study is consistent with the previous study by Vilainerun N., Hanutsaha P, 5 which also showed that out of the total 20 patients with HCQ retinopathy, 70% (14 of 20) had a parafoveal pattern. Given that the SITA Standard 24 − 2 is the current program standard for detecting CQ/HCQ retinopathy in the Asian population, as recommended by the American Academy of Ophthalmology. 3 we aim to highlight the importance of raising suspicion when a visual field defect occurs, even if it involves only a single point on any of the four fixation points, representing a defect within a 6-degree radius from the fovea. Such defects might be evident in the group of patients with CQ/HCQ retinopathy, particularly in the parafoveal pattern. Wide field SD-OCT might be benefit for screening CQ/HCQ retinopathy in the Asian population. In our study, 61.5% (16 of 26 cases) of CQ/HCQ retinopathy were diagnosed based on VF defects, confirmed by abnormal signals in mfERG without any evidence of structural changes from SD-OCT and FAF. Among these cases, 10 of 16 cases (62.5%) were categorized as having a pericentral pattern. Comparison with previous study conducted by Marmor MF and Melles RB in California, 20 found a 10% disparity between VF and SD-OCT findings in HCQ retinopathy with a parafoveal pattern, our study suggests that the higher prevalence of pericentral patterns in the Asian population may lead to the oversight of lesions at the periphery of SD-OCT. As a result, This concept is supported by a study conducted in South Korea by Seong Joon Ahn et al, 21 which demonstrated that 9-mm line scans from wide-field OCT detected HCQ retinopathy significantly better than 6-mm scans from SD-OCT. The SITA Faster 24-2C test offers the advantage of a shorter test duration compared to the SITA Standard 24 − 2 (2.2 minutes versus 4.5 minutes; P < 0.001). Our study aligns with previous research, confirming the efficiency of the SITA Faster 24-2C, as it significantly reduces testing time compared to the SITA Standard 24 − 2 (155 versus 314 seconds). 12 With regard to the SITA Faster 24-2C, several modifications were implemented to expedite this strategy, 16 such as age-corrected starting stimulus intensities, a reduction in reversals at primary test points, utilization of the distribution of SITA Fast normal values, absence of a second check on perimetrically blind points, absence of false-negative catch trials, fixation verification through gaze tracking, and elimination of extra delay times. This benefit facilitates more frequent testing, reduces fatigue during testing, and thereby improves the ability to detect the disease. Based on the results of our study and the modifications of the SITA Faster 24-2C strategy, we recommend using the SITA Faster 24-2C for monitoring CQ/HCQ retinopathy in patients who are experienced with VF testing. This recommendation is due to the shorter test duration and reduced fatigue associated with this method. This study has several limitations that warrant consideration. First, the prevalence of CQ/HCQ retinopathy is relatively low in our study (26 of 75 cases, 34.7%). Additionally, 10 participants (11.8%) were excluded due to unreliable VF or evidence of other maculopathy, potentially impacting the power to discern differences in VF parameters between SITA Faster 24-2C and SITA Standard 24 − 2. Second, VF, SD-OCT, and FAF results may differ based on the location and extent of the retinopathy. For instance, cases with early pericentral retinopathy may not show central scotomas. 22 Therefore, our graders determined defects based on a literature review and their experiences. Last, our study design lacked a repeat test on the same day or within a short period to confirm the VF defects. Given the subjective nature of VF testing, confirmation testing could potentially reduce false positives and false negatives. 23 – 25 CONCLUSION Both the SITA Faster 24-2C and SITA Standard 24 − 2 tests are comparable in screening for CQ/HCQ retinopathy and show strongly positive agreement. However, the SITA Faster 24-2C offers the advantage of shorter test duration. Integrating the results with SD-OCT including wide field scanning, FAF, and mfERG helps clinicians in achieving a precise diagnosis. The addition of testing points within the central 10-degree radius does not enhance the detection of CQ/HCQ retinopathy in the Thai populations. Declarations ACKNOWLEDGEMENTS & DISCLOSURES a) Financial Support: Ratchadapiseksompotch Fund, Graduate Affairs, Faculty of Medicine, Chulalongkorn University, Grant number 65/54 b) Financial Disclosures: The authors declare no conflict of interest. c) Other Acknowledgements: None References Yusuf IH, Sharma S, Luqmani R, Downes SM. Hydroxychloroquine retinopathy. Eye (Lond) . Jun 2017;31(6):828-845. doi:10.1038/eye.2016.298 Melles RB, Marmor MF. The risk of toxic retinopathy in patients on long-term hydroxychloroquine therapy. JAMA Ophthalmol . Dec 2014;132(12):1453-60. doi:10.1001/jamaophthalmol.2014.3459 Marmor MF, Kellner U, Lai TY, Melles RB, Mieler WF, American Academy of O. Recommendations on Screening for Chloroquine and Hydroxychloroquine Retinopathy (2016 Revision). Ophthalmology . Jun 2016;123(6):1386-94. doi:10.1016/j.ophtha.2016.01.058 Melles RB, Marmor MF. Pericentral retinopathy and racial differences in hydroxychloroquine toxicity. Ophthalmology . Jan 2015;122(1):110-6. doi:10.1016/j.ophtha.2014.07.018 Vilainerun N HP. Patterns of Hydroxychloroquine and Chloroquine Retinopathy in Thai Patients. Thai J Ophthalmol . 2019;33(2):66-75. Grillo LM, Wang DL, Ramachandran R, et al. The 24-2 Visual Field Test Misses Central Macular Damage Confirmed by the 10-2 Visual Field Test and Optical Coherence Tomography. Transl Vis Sci Technol . Apr 2016;5(2):15. doi:10.1167/tvst.5.2.15 Chakravarti T, Moghadam M, Proudfoot JA, Weinreb RN, Bowd C, Zangwill LM. Agreement Between 10-2 and 24-2C Visual Field Test Protocols for Detecting Glaucomatous Central Visual Field Defects. J Glaucoma . Jun 1 2021;30(6):e285-e291. doi:10.1097/IJG.0000000000001844 Yamane MLM, Odel JG. Introducing the 24-2C Visual Field Test in Neuro-Ophthalmology. J Neuroophthalmol . Dec 1 2021;41(4):e606-e611. doi:10.1097/WNO.0000000000001157 Greenstein VC, Amaro-Quireza L, Abraham ES, Ramachandran R, Tsang SH, Hood DC. A comparison of structural and functional changes in patients screened for hydroxychloroquine retinopathy. Doc Ophthalmol . Feb 2015;130(1):13-23. doi:10.1007/s10633-014-9474-6 Marmor MF. Comparison of screening procedures in hydroxychloroquine toxicity. Arch Ophthalmol . Apr 2012;130(4):461-9. doi:10.1001/archophthalmol.2011.371 Michaelides M, Stover NB, Francis PJ, Weleber RG. Retinal toxicity associated with hydroxychloroquine and chloroquine: risk factors, screening, and progression despite cessation of therapy. Arch Ophthalmol . Jan 2011;129(1):30-9. doi:10.1001/archophthalmol.2010.321 Phu J, Kalloniatis M. Ability of 24-2C and 24-2 Grids to Identify Central Visual Field Defects and Structure-Function Concordance in Glaucoma and Suspects. Am J Ophthalmol . Nov 2020;219:317-331. doi:10.1016/j.ajo.2020.06.024 Su S, Callan T, Yu S, et al. Comparison of 24-2C SITA Standard and 24-2C SITA Faster. Investigative Ophthalmology & Visual Science . 2022;63(7):1267 – A0407-1267 – A0407. Bland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. Lancet . Feb 8 1986;1(8476):307-10. Costa VP, Zangalli CS, Jammal AA, et al. 24-2 SITA Standard versus 24-2 SITA Faster in Perimetry-Naive Normal Subjects. Ophthalmol Glaucoma . Mar-Apr 2023;6(2):129-136. doi:10.1016/j.ogla.2022.08.006 Heijl A, Patella VM, Chong LX, et al. A New SITA Perimetric Threshold Testing Algorithm: Construction and a Multicenter Clinical Study. Am J Ophthalmol . Feb 2019;198:154-165. doi:10.1016/j.ajo.2018.10.010 Choi EY, Li D, Fan Y, et al. Predicting Global Test-Retest Variability of Visual Fields in Glaucoma. Ophthalmol Glaucoma . Jul-Aug 2021;4(4):390-399. doi:10.1016/j.ogla.2020.12.001 Katz J, Sommer A. Screening for glaucomatous visual field loss. The effect of patient reliability. Ophthalmology . Aug 1990;97(8):1032-7. doi:10.1016/s0161-6420(90)32467-3 Chen E, Brown DM, Benz MS, et al. Spectral domain optical coherence tomography as an effective screening test for hydroxychloroquine retinopathy (the "flying saucer" sign). Clin Ophthalmol . Oct 21 2010;4:1151-8. doi:10.2147/OPTH.S14257 Marmor MF, Melles RB. Disparity between visual fields and optical coherence tomography in hydroxychloroquine retinopathy. Ophthalmology . Jun 2014;121(6):1257-62. doi:10.1016/j.ophtha.2013.12.002 Ahn SJ, Joung J, Lim HW, Lee BR. Optical Coherence Tomography Protocols for Screening of Hydroxychloroquine Retinopathy in Asian Patients. Am J Ophthalmol . Dec 2017;184:11-18. doi:10.1016/j.ajo.2017.09.025 Kim KE, Ryu SJ, Kim YH, Seo Y, Ahn SJ. Visual field examinations using different strategies in Asian patients taking hydroxychloroquine. Sci Rep . Aug 30 2022;12(1):14778. doi:10.1038/s41598-022-19048-0 Keltner JL, Johnson CA, Quigg JM, Cello KE, Kass MA, Gordon MO. Confirmation of visual field abnormalities in the Ocular Hypertension Treatment Study. Ocular Hypertension Treatment Study Group. Arch Ophthalmol . Sep 2000;118(9):1187-94. doi:10.1001/archopht.118.9.1187 Kim J, Dally LG, Ederer F, et al. The Advanced Glaucoma Intervention Study (AGIS): 14. Distinguishing progression of glaucoma from visual field fluctuations. Ophthalmology . Nov 2004;111(11):2109-16. doi:10.1016/j.ophtha.2004.06.029 Schulzer M. Errors in the diagnosis of visual field progression in normal-tension glaucoma. Ophthalmology . Sep 1994;101(9):1589-94; discussion 1595. doi:10.1016/s0161-6420(94)31133-x Additional Declarations There is no conflict of interest Supplementary Files SupplementTable1.docx Supplement Table1 Cite Share Download PDF Status: Published Journal Publication published 05 May, 2026 Read the published version in Eye → Version 1 posted Editorial decision: revise 11 Nov, 2025 Review # 1 received at journal 05 Oct, 2025 Reviewer # 1 agreed at journal 05 Oct, 2025 Reviewers invited by journal 01 Oct, 2025 Editor assigned by journal 05 Jun, 2025 Submission checks completed at journal 29 May, 2025 First submitted to journal 28 May, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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1","display":"","copyAsset":false,"role":"figure","size":538912,"visible":true,"origin":"","legend":"\u003cp\u003eDiagnostic criteria for chloroquine/hydroxychloroquine (CQ/HCQ) retinopathy using visual field (VF), spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF) and multifocal electroretinography (mfERG)\u003c/p\u003e","description":"","filename":"Figure1.tif.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6769459/v1/481d4379d086b2fa1b8edebb.jpg"},{"id":93556224,"identity":"91358593-ce83-4860-b95b-0cd818f97353","added_by":"auto","created_at":"2025-10-15 06:41:47","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":420144,"visible":true,"origin":"","legend":"\u003cp\u003eA Diagram illustrating the study flow for diagnosing chloroquine/hydroxychloroquine (CQ/HCQ) retinopathy using visual field (VF) testing, spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF) and multifocal electroretinography (mfERG)\u003c/p\u003e","description":"","filename":"Figure2.tif.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6769459/v1/4095d9f4adaa9d8d28d3f8ce.jpg"},{"id":93556222,"identity":"2913e663-2b66-413c-869e-6af04d2bab71","added_by":"auto","created_at":"2025-10-15 06:41:47","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":802859,"visible":true,"origin":"","legend":"\u003cp\u003eA case of a 43-year-old female patient who had been taking chloroquine 250 mg daily for 15 years. She had a history of chronic kidney disease and was diagnosed with chloroquine-induced retinopathy. Abnormalities were detected on visual field tests, specifically in the SITA Standard 24-2 (A) and SITA Faster 24-2C (B) pattern deviation maps.However, both spectral-domain optical coherence tomography (C) and fundus autofluorescence (D) revealed no noticeable retinal changes. The definitive diagnosis was subsequently confirmed through multifocal electroretinography (E), which showed significantly reduced foveal and parafoveal amplitudes.\u003c/p\u003e","description":"","filename":"Figure3.tif.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6769459/v1/6fddd3f04e87c7469abb7592.jpg"},{"id":93556231,"identity":"42a0259a-9481-44f1-8ad4-b2240545be69","added_by":"auto","created_at":"2025-10-15 06:41:47","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":929820,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of chloroquine/hydroxychloroquine retinopathy patterns using SITA Standard 24-2, SITA Faster 24-2C, spectral-domain optical coherence tomography (SD-OCT), and fundus autofluorescence (FAF): A.) Parafoveal pattern showing a central to paracentral scotoma in both visual fields, with parafoveal thinning of ellipsoid zone band, disruption of interdigitation zone band on SD-OCT (arrow) and unremarkable FAF. B.) Pericentral pattern showing a pericentral scotoma in both visual fields, with thinning of ellipsoid zone band and disruption of interdigitation zone band nasal to fovea on SD-OCT (arrow), correlate with subtle hyper FAF at the nasal side of macula. C.) Mixed pattern showing both parafoveal and pericentral scotoma in the visual fields, with thinning of ellipsoid zone band, disruption of interdigitation zone band nasal to fovea on SD-OCT (arrow) and unremarkable FAF.\u003c/p\u003e","description":"","filename":"Figure4.tif.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6769459/v1/f21487de6c3617f68007ee93.jpg"},{"id":93557399,"identity":"b50d53d8-3542-4109-b2c2-4878ad245941","added_by":"auto","created_at":"2025-10-15 06:49:47","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":456021,"visible":true,"origin":"","legend":"\u003cp\u003eLinear regression analysis (left) and Bland-Altman plots (right) were performed on visual field (VF) parameters from 150 VF tests using both SITA Standard 24-2 and SITA Faster 24-2C: A) Mean deviation: Limit of agreement (LoA) = -2.7 to 2.3; Concordance Correlation Coefficient (CCC) = 0.93 (95% confidence interval [CI]: 0.89-0.96), B) Pattern standard deviation: LoA = -1.8 to 1.5; CCC = 0.89 (95%CI: 0.84-0.94), C) Central mean sensitivity: LoA = -1.96to 2.19; CCC = 0.93 (95%CI: 0.89-0.96).\u003c/p\u003e","description":"","filename":"Figure5.tif.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6769459/v1/793705854d8a9e5583fdd39d.jpg"},{"id":108477370,"identity":"52d03544-f896-4fa3-94db-83d39632800a","added_by":"auto","created_at":"2026-05-05 07:11:09","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":3496016,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6769459/v1/ba36ed96-ffe0-44ae-ad2a-004fbe8709a1.pdf"},{"id":93556221,"identity":"ff5fd60c-43d0-4922-9967-dc1b86098332","added_by":"auto","created_at":"2025-10-15 06:41:46","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":21641,"visible":true,"origin":"","legend":"Supplement Table1","description":"","filename":"SupplementTable1.docx","url":"https://assets-eu.researchsquare.com/files/rs-6769459/v1/5e79c6a3e5579afa7d524650.docx"}],"financialInterests":"There is no conflict of interest","formattedTitle":"Agreements between 24-2 and 24-2C Test Grids for Chloroquine/Hydroxychloroquine Retinopathy Patients and High-Risk Patients","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eChloroquine (CQ) and Hydroxychloroquine (HCQ) are commonly used in the treatment of autoimmune diseases, notably systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA).\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e Their widespread use is attributed to their favorable safety profiles and minimal physical side effects. However, it is important to acknowledge that their adverse effects can lead to incurable retinopathy. The prevalence of CQ/HCQ retinopathy stands at 7.5% within 5 years and escalates to 20% after 20 years of continuous CQ/HCQ administration.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e Key risk factors associated with retinopathy include dosages exceeding 2.3 mg/kg for CQ and 5 mg/kg for HCQ, prolonged usage surpassing 5 years, renal impairment, concurrent usage with tamoxifen, and a history of prior retinopathy. Concomitantly, minor risk factors are advanced age, hepatic, and hereditary conditions.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e Furthermore, CQ/HCQ retinopathy continues to progress even after discontinuation of the drug. Therefore, early CQ/HCQ retinopathy detection is essential for effectively preventing irreversible retinopathy.\u003c/p\u003e\u003cp\u003eAutomated visual field (VF) testing, together with spectral domain optical coherence tomography (SD-OCT), constitutes one of the fundamental diagnostic tools for the detection of CQ/HCQ retinopathy. In accordance with the recommendations provided by the American Academy of Ophthalmology in 2016,\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e fundus autofluorescence (FAF) and multifocal electroretinography (mfERG) also play a significant role in diagnosing this condition. Moreover, the guidelines suggest the use of a broader VF test, such as the 24\u0026thinsp;\u0026minus;\u0026thinsp;2 or 30\u0026thinsp;\u0026minus;\u0026thinsp;2, for individuals of Asian descent, as opposed to the 10\u0026thinsp;\u0026minus;\u0026thinsp;2 test commonly employed for Caucasians. This recommendation is grounded in research indicating that 50% of Asians frequently exhibit VF defects at distances exceeding 8 degrees from the fovea.\u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e In contrast, a 2019 study conducted in Thailand revealed that up to 70% of HCQ retinopathy cases manifest VF defects in parafoveal areas (2\u0026ndash;7 degrees from the fovea).\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e Consequently, employing a wide VF test spanning 24 or 30 degrees, which assesses the parafoveal region with only four points, may miss certain patients. The study further underscores that 12% of glaucoma patients, who exhibit retinopathy detected through a 10\u0026thinsp;\u0026minus;\u0026thinsp;2 or 10-degree VF test and SD-OCT, may not exhibit irregularities in the 24\u0026thinsp;\u0026minus;\u0026thinsp;2 VF test.\u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe Humphrey VF Swedish Interactive Threshold Algorithm (SITA) Faster 24-2C (Carl Zeiss Meditec, Germany) was developed in 2019 with the specific aim of enhancing sensitivity for detecting glaucoma.\u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e This was achieved by incorporating an additional 10 test points within the central 10-degree radius. Additionally, a faster algorithm was implemented to reduce test duration. A recent study has shown that SITA Faster 24-2C exhibits a correlation with VF parameters when compared to the 10\u0026thinsp;\u0026minus;\u0026thinsp;2 test in both glaucoma and neuro-ophthalmological patients.\u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e This suggests that the 24-2C test is capable of detecting abnormalities that are also identified by the 10\u0026thinsp;\u0026minus;\u0026thinsp;2 test. However, there is currently no existing study that specifically examines the utility of the 24-2C test in the context of CQ/HCQ retinopathy. Therefore, the primary objective of this study is to evaluate the agreements between SITA Faster 24-2C as compared to SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 for the screening of CQ/HCQ retinopathy within the Thai population.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy Design and Population\u003c/h2\u003e\u003cp\u003e This prospective cross-sectional study received approval from the Institutional Review Board of the Faculty of Medicine, Chulalongkorn University under IRB number 0172/65. It was registered with the Thai Clinical Trials Registry (TCTR) under the number TCTR20231019002. The research adhered to the principles of the Declaration of Helsinki and was financially supported by the Ratchadapiseksumpotch Fund for Graduate Affairs, Faculty of Medicine, Chulalongkorn University, under Grant number GA65/54. Informed consent was obtained from all study participants following IRB approval.\u003c/p\u003e\u003cp\u003eThe eligible study participants included patients diagnosed with CQ/HCQ retinopathy and those classified as high-risk patients based on meeting one or more of the following criteria: a CQ dosage exceeding 2.3 mg/kg of real weight, an HCQ dosage exceeding 5 mg/kg of real weight, prolonged usage beyond 5 years, the presence of kidney disease with a subnormal glomerular filtration rate, or concurrent use of tamoxifen. Participants were also required to be 18 years of age or older and possess a documented history of reliable automated perimetry. These eligible participants were recruited from the ophthalmology clinic at King Chulalongkorn Memorial Hospital. The exclusion criteria encompassed individuals exhibiting unreliable VF tests, which were defined as having a fixation loss greater than 20% or false positives exceeding 15%. Furthermore, individuals with suboptimal quality SD-OCT (quality score of less than 15 from SPECTRALIS\u0026reg; OCT), FAF images, as well as those affected by other ocular conditions, such as alternative causes of retinopathy, optic neuropathy, or optical media opacities that could potentially influence perimetry results, were excluded from the study. Patients with contraindications for pupil dilatation were also deemed ineligible.\u003c/p\u003e\u003cp\u003eIn this study, one eye per patient was considered, focusing on the eye affected by CQ/HCQ retinopathy. In cases of bilateral disease or the non-retinopathy group, the right eye was prioritized unless it exhibited unreliable VF results or suboptimal imaging quality.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eClinical Examination \u0026 Diagnosis\u003c/h3\u003e\n\u003cp\u003eEach patient underwent a VF test using both SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 and SITA Faster 24-2C of Humphrey visual field analyzer (Carl Zeiss Meditec, Germany), administered in a randomized order by computerized random generator, with a 15-minute interval between tests. This investigation was followed by fundus photography and FAF imaging by CLARUS\u0026trade; 500 (Carl Zeiss Meditec, Germany), and SD-OCT by SPECTRALIS\u0026reg; (Heidelberg Engineering Inc., USA) under dilated pupils. All tests were performed on the same day by one experienced technician using identical equipment throughout the study. In the following, a comprehensive eye examination was conducted by an ophthalmologist (K.R.), who remained blinded to the patients' medical histories, to assess for other ocular conditions that could potentially impact the VF, SD-OCT, and FAF.\u003c/p\u003e\u003cp\u003eAll reliable SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 test results were forwarded to two glaucoma specialists (K.R. and S.C.) for interpretation to determine the presence of CQ/HCQ retinopathy based on expert opinions and the VF criteria of CQ/HCQ retinopathy, which present as a reduction in VF sensitivity, such as a small central defect on the pattern deviation where one or more of the four central points around fixation had a probability of \u0026lt;\u0026thinsp;1%.\u003csup\u003e9\u003c/sup\u003e In cases where there was a discrepancy in their interpretations, a third glaucoma specialist (A.M.) provided the final judgment. Similarly, SD-OCT and FAF results were transmitted to and interpreted by two retina specialists (D.S. and W.C.). The interpretations were primarily based on expert opinions and commonly reported findings. These included subtle changes in SD-OCT indicative of early toxicity, distinct thinning of the outer retina near the fovea resembling a \u0026lsquo;flying saucer\u0026rsquo; shape, and hyperfluorescence around the fovea in cases of moderate toxicity. In severe toxicity, extensive thinning beyond the fovea obscured the bull\u0026rsquo;s-eye pattern, with additional widespread hyperfluorescence, RPE disruption, and evidence of RPE cell loss observed.\u003csup\u003e\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e If disagreements between the initial two specialists remained unresolved, a third specialist (P.F.) was consulted to provide a final assessment.\u003c/p\u003e\u003cp\u003eThe diagnosis of CQ/HCQ retinopathy was primarily based on the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 test, as delineated in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. In the case where abnormalities suggestive of CQ/HCQ retinopathy were identified using the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 test and were further supported findings in SD-OCT or FAF images, a diagnosis of CQ/HCQ retinopathy was confirmed. In instances where VF defects were observed without concurrent structural evidence, mfERG showing amplitude reduction or delayed implicit time was used to confirm central macular dysfunction.\u003csup\u003e\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e In the case of a normal VF, patients will be categorized into the high-risk CQ/HCQ retinopathy (non-retinopathy group). Additionally, those with abnormal VF but without structural defects and normal signals in mfERG will also be classified as part of the non-retinopathy group.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eFinally, the agreements between SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 in terms of mean deviation (MD), pattern standard deviation (PSD), and central mean sensitivity (CMS), and the number of flagged pattern deviation points at P\u0026thinsp;\u0026lt;\u0026thinsp;1% in central 10 degree were assessed for retinopathy and non-retinopathy group separately.\u003c/p\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003eStatistical Analysis\u003c/h2\u003e\u003cp\u003eThe sample size for this study was calculated as 75 eyes, based on intraclass correlation coefficient estimation at 0.75 expected reliability, 95% confidence interval of 0.1 precision, and an expected dropout rate of 10%. We used descriptive statistics to assess the demographic data of the groups. The Wilcoxon rank sum tests were used to compare data between retinopathy and non-retinopathy groups. The Wilcoxon signed-rank test was used to compare data between SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2. The Bland-Altman plot and Concordance Correlation Coefficient (CCC) were used to assess agreement between the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 and SITA Faster 24-2C tests. The 95% limits of agreement (LoA) shown in the Bland-Altman plot are defined as the mean difference\u0026thinsp;\u0026plusmn;\u0026thinsp;1.96 standard deviations. Statistical analysis was performed using the STATA version 18.0 (StataCorp LLC, Texas, USA). A P-value of 0.05 was considered statistically significant.\u003c/p\u003e\u003c/div\u003e"},{"header":"RESULTS","content":"\u003cp\u003eA total of 85 participants were initially recruited for this study. However, 10 participants (11.8%) were subsequently excluded due to unreliable visual fields, and other ocular diseases affecting visual field tests. Among the remaining 75 participants, 26 were classified into the retinopathy group and 49 into the non-retinopathy group based on the specified criteria (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e presents the demographic characteristics. The median age was 51.5 years in the retinopathy group and 45 years in the non-retinopathy group, with a predominance of females. The median weight was 55 kg in the retinopathy group and 53 kg in the non-retinopathy group. Most patients in both groups were treated with HCQ, with SLE being the primary indication for treatment. However, RA was more common in the retinopathy group. The median treatment duration was 9 years for both groups. Kidney involvement was more common in the non-retinopathy group, while liver involvement was rare across both groups.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eBaseline Demographics of Study Patients\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCharacteristics\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eRetinopathy\u003c/p\u003e\u003cp\u003e(N\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e\u003cp\u003eNon-retinopathy\u003c/p\u003e\u003cp\u003e(N\u0026thinsp;=\u0026thinsp;49)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eP-value\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge, years (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e51.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(42\u0026ndash;46)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e45\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(34\u0026ndash;55)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.11\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFemale, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(96.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(87.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.41\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWeight, kg (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(55\u0026ndash;70)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(48\u0026ndash;61)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.13\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCQ/HCQ uses, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.07\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHCQ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(69.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(73.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCQ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(30.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(26.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDose per day, mg (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHCQ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e200\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(200\u0026ndash;200)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e200\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(200\u0026ndash;200)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.26\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCQ\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e250\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(250\u0026ndash;250)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e250\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(250\u0026ndash;250)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.34\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIndication of CQ/HCQ usage, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.03*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSLE\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(53.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(81.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRA\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(30.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(10.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOthers\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(15.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(8.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDuration of CQ/HCQ usage, years (median [IQR])\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(5\u0026ndash;16)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(7-12.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.73\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eConcomitant disease, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eKidney disease\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(30.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(61.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.01*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLiver disease\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(3.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e(0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.35\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e\u003cp\u003eCQ indicates chloroquine; HCQ, hydroxychloroquine; SLE, systemic lupus erythematosus; RA, rheumatoid arthritis\u003c/p\u003e\u003cp\u003eThe data was reported as median (IQR) for continuous variables and frequency count (%) for categorical variables.\u003c/p\u003e\u003cp\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e P-values obtained using Wilcoxon rank sum test and Chi square test for comparing data between retinopathy and non-retinopathy group\u003c/p\u003e\u003cp\u003e* Statistically significant P-value\u0026thinsp;\u0026lt;\u0026thinsp;.05\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eIn accordance with the diagram illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, among 26 individuals in the retinopathy group, 16 presented with abnormal visual field test results but showed no structural defects in either SD-OCT or FAF. Subsequently, they were diagnosed with a reduced foveal signal amplitudes in the mfERG, as illustrated by a representative case in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. The remaining 10 patients exhibited abnormalities in both visual field tests and structural defects, which were identified through either SD-OCT, FAF, or both (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). A total of 26 patients diagnosed with CQ/HCQ retinopathy presented varying lesions in specific retinal areas: 10 cases (38.5%) exhibited parafoveal changes (2\u0026ndash;6 degrees from the fovea), 12 cases (46.1%) displayed pericentral alterations (outside 8 degrees from the fovea), and a mixed pattern was observed in 4 cases (15.4%), as depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e through VF testing, SD-OCT, or FAF. Among the patients with a pericentral pattern, 83% (10 out of 12) were diagnosed with retinopathy without abnormalities detected in either SD-OCT or FAF.\u003c/p\u003e\u003cp\u003eRegards to VF parameters, including MD, PSD, and CMS values, statistically significant differences were observed between the retinopathy and non-retinopathy groups in both VF tests (SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2; P\u0026thinsp;\u0026lt;\u0026thinsp;0.048), except for the number of flagged pattern deviation points at P\u0026thinsp;\u0026lt;\u0026thinsp;1% in central 10 degree, where no statistically significant difference was observed when testing with SITA Faster 24-2C (P\u0026thinsp;=\u0026thinsp;0.09), as presented in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. However, within each group, their results were comparable across all VF parameters between the two tests (P\u0026thinsp;=\u0026thinsp;0.08\u0026ndash;0.98) except for PSD in the retinopathy group (1.73 dB in SITA Faster 24-2C versus 2.14 dB in SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2; P\u0026thinsp;=\u0026thinsp;0.02). Additionally, Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e indicates that both VF tests exhibited a strong positive correlation in terms of MD, PSD, and CMS values, with a coefficient ranging from 0.89 to 0.93. The testing duration for SITA Faster 24-2C was significantly shorter than for SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 (2.2 minutes versus 4.5 minutes; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of Visual Field Parameters Between Retinopathy and Non-Retinopathy Groups Using SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"8\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e\u003cp\u003eRetinopathy (N\u0026thinsp;=\u0026thinsp;26)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e\u003cp\u003eNon-Retinopathy (N\u0026thinsp;=\u0026thinsp;49)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eP-value\u003csup\u003e\u0026dagger;\u0026dagger;\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003ctr\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e\u003cp\u003eMedian (IQR)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eP-value\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e\u003cp\u003eMedian (IQR)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eP-value\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMean deviation (dB)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA faster 24-2C\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-1.89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(-3.63 to -0.72)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(-2.22 to -0.30)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.04*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e-1.70\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(-3.70 to -0.54)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-0.96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(-1.99 to 0.21)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.02*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePattern standard deviation (dB)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA faster 24-2C\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(1.41\u0026ndash;2.79)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.02*\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(1.29\u0026ndash;1.76)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.048*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.14\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(1.81\u0026ndash;2.81)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1.49\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(1.37\u0026ndash;1.79)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCentral mean sensitivity (dB)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA faster 24-2C\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e31.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(28.7\u0026ndash;32.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e32.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(31.5\u0026ndash;33.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e31.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(28.0-31.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e32.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(31.0\u0026ndash;33.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eThe number of flagged pattern deviation points at P\u0026thinsp;\u0026lt;\u0026thinsp;1% in central 10 degree\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA faster 24-2C\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(0\u0026ndash;3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(0\u0026ndash;1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.09\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u0026bull; SITA standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e(1\u0026ndash;5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e(0\u0026ndash;0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001*\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colspan=\"8\" nameend=\"c8\" namest=\"c1\"\u003e\u003cp\u003eThe data was reported as median (IQR) for continuous variables.\u003c/p\u003e\u003cp\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e P-values obtained using Wilcoxon signed-rank test for comparing continuous data between SITA faster 24-2C and SITA standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2\u003c/p\u003e\u003cp\u003e\u003csup\u003e\u0026dagger;\u0026dagger;\u003c/sup\u003e P-values obtained using Wilcoxon rank sum test for comparing continuous data between retinopathy and non-retinopathy groups\u003c/p\u003e\u003cp\u003e* Statistically significant P-value\u0026thinsp;\u0026lt;\u0026thinsp;.05\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows that two missing patients who did not undergo mfERG were categorized as part of the non-retinopathy group due to incomplete criteria. However, to prevent unintentional bias, we conducted an additional analysis in which these patients were classified as part of the retinopathy group. The results indicate no significant difference between the two analyses, except for the number of flagged pattern deviation points at P\u0026thinsp;\u0026lt;\u0026thinsp;1% in the central 10 degrees of the SITA Faster 24-2C test, where a significant difference was observed between the retinopathy and non-retinopathy groups (P\u0026thinsp;=\u0026thinsp;0.02). (Supplementary Table\u0026nbsp;1)\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eOur study found that both the SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 are effective in detecting CQ/HCQ retinopathy, showing strong correlations between MD, PSD, and CMS across VF tests. However, the 24-2C test offers the benefit of a shorter test duration and demonstrates a significantly lower PSD in retinopathy cases. In Asian populations, CQ/HCQ-induced retinopathy manifests in pericentral, parafoveal, or combined patterns, with reduced CMS confirming parafoveal involvement. Monitoring within a 6-degree radius from the fovea is crucial. For pericentral patterns, utilizing wide-field SD-OCT may improve screening accuracy by detecting changes that standard SD-OCT could miss.\u003c/p\u003e\u003cp\u003eThe performance of the SITA Faster 24-2C test grid, compared to the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 test, demonstrates comparable results in detecting CQ/HCQ retinopathy (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). In addition, our study revealed that both SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 tests exhibited statistically significant reductions in MD and CMS values, as well as increases in PSD in the retinopathy group compared to the non-retinopathy group (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, P\u0026thinsp;\u0026lt;\u0026thinsp;0.048). This finding is similar to the previous study that observed comparable VF indices between 24\u0026thinsp;\u0026minus;\u0026thinsp;2 and 24-2C in individuals with glaucoma and those suspected of having glaucoma.\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e,\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e These noted deteriorations in these parameters underscore the importance of VF testing in helping clinicians identify suspected cases of CQ/HCQ retinopathy.\u003c/p\u003e\u003cp\u003eThere is good reliability and consistency of both SITA Faster 24-2C and the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 in detecting CQ/HCQ retinopathy (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Bland-Altman plots were used to demonstrate agreement and the magnitude of differences between algorithms to avoid the misleading effects of correlation coefficients alone.\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e The results not only reported a strong positive correlation exists between the two VF tests in terms of MD, PSD, and CMS, but Bland-Altman plots also showed good agreement between tests (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e), which is similar to prior studies\u003csup\u003e\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e,\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. The 95% limits of agreement for mean deviation (MD) between the two strategies ranged from \u0026minus;\u0026thinsp;2.7 to +\u0026thinsp;2.3 dB, indicating that the difference in MD between 24-2C and 24\u0026thinsp;\u0026minus;\u0026thinsp;2 did not exceed 2.7 dB in either direction in 95% of cases. Such variability is consistent with known test-retest fluctuations in visual field testing and remains within clinically acceptable limits. This interpretation is supported by a large-scale study by Choi et al.\u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e, which reported a mean absolute MD difference of 1.7 dB and an intraclass correlation coefficient (ICC) of 0.92 between the first and retest MD measurements using the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2. In that study, when the baseline MD was approximately \u0026minus;\u0026thinsp;2 dB, the retest values varied widely, ranging from nearly 0 dB to worse than \u0026minus;\u0026thinsp;5 dB. This indicates that fluctuations exceeding 2.7 dB can occur within a single test\u0026ndash;retest pair, supporting the notion that the observed inter-strategy difference remains within expected physiological variability.\u003c/p\u003e\u003cp\u003eThere were no statistically significant differences in any parameters, including MD, PSD, CMS, and the number of flagged pattern deviation points with P\u0026thinsp;\u0026lt;\u0026thinsp;1% within the central 10 degrees between the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 and SITA Faster 24-2C in the non-retinopathy group. However, in the retinopathy group, a statistically significant lower or better PSD was observed in the 24-2C test compared to the 24\u0026thinsp;\u0026minus;\u0026thinsp;2 test (1.73 dB vs. 2.14 dB, P\u0026thinsp;=\u0026thinsp;0.02, Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). While this difference is statistically significant, it may not necessarily indicate a clinically meaningful difference. PSD is influenced by several factors beyond retinal pathology, including fixation stability\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e location and extent of visual field defect, severity of diseases, and algorithm strategies. Additionally, Medeiros et al. reported that perimetry-naive individuals exhibited lower PSD values when tested with the SITA Faster 24-2C strategy compared to the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 strategy (1.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.80 dB vs. 2.15\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25 dB, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.016),\u003csup\u003e15\u003c/sup\u003e which is consistent with the findings of our study. Therefore, while statistically significant, the difference in PSD between the two strategies in our study may reflect intrinsic differences in algorithm design rather than true disparities in disease detection.\u003c/p\u003e\u003cp\u003eWhen using SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 strategy, the number of flagged pattern deviation points at \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;1% within the central 10 degrees was significantly higher in the retinopathy group compared to the non-retinopathy group (P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). In contrast, the SITA Faster 24-2C strategy showed only a marginally significant difference (P\u0026thinsp;=\u0026thinsp;0.09). This finding is consistent with previous studies involving patients with glaucoma and glaucoma suspects, which also reported a slightly higher number of test points showing significant depression at P\u0026thinsp;\u0026lt;\u0026thinsp;1% on the pattern deviation plot when using the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 strategy compared to SITA Faster 24-2.\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e However, in our study, no statistically significant differences were observed between the two strategies across comparisons (P\u0026thinsp;=\u0026thinsp;0.20\u0026ndash;0.76; Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). These findings suggest that although the SITA Faster 24-2C provides additional central test points, it does not enhance the detection of visual field defects in the screening of HCQ retinopathy. This result may be due to two reasons: 1) the prevalence of more pericentral CQ/HCQ retinopathy patterns in Asians,\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e,\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e which may not benefit from adding 10 central points using SITA Faster 24-2C; and 2) The locations of these additional points, areas more susceptible to glaucomatous damage in the ganglion cell layer and retinal nerve fiber layer, may not effectively represent the early changes of CQ/HCQ retinopathy, which primarily affects the outer retinal layer and photoreceptors.\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e Our analysis focused on the central 10-degree region, where the structural differences between the two test strategies are most evident. The SITA Faster 24-2C includes 10 additional central test points that are not present in the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2. Outside this region, both strategies have identical test point locations and densities. Therefore, limiting the analysis to the central 10 degrees provides the most meaningful basis for comparison and highlights the specific contribution of the additional test points introduced in the 24-2C strategy.\u003c/p\u003e\u003cp\u003eIn relation to VF damage in CQ/HCQ retinopathy, not only do pericentral lesions occur, but parafoveal lesions are also observed in the Asian population. Our study found a reduction in CMS within a 10-degree radius in both the 24\u0026thinsp;\u0026minus;\u0026thinsp;2 and 24-2C tests among the CQ/HCQ retinopathy group. Additionally, SD-OCT revealed parafoveal patterns in 38.5% of cases, and mixed patterns (both pericentral and parafoveal lesions) in 15.4% of cases. These findings provide confirmed evidence of parafoveal lesions in Asians. Our study is consistent with the previous study by Vilainerun N., Hanutsaha P,\u003csup\u003e\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e which also showed that out of the total 20 patients with HCQ retinopathy, 70% (14 of 20) had a parafoveal pattern. Given that the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 is the current program standard for detecting CQ/HCQ retinopathy in the Asian population, as recommended by the American Academy of Ophthalmology.\u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e we aim to highlight the importance of raising suspicion when a visual field defect occurs, even if it involves only a single point on any of the four fixation points, representing a defect within a 6-degree radius from the fovea. Such defects might be evident in the group of patients with CQ/HCQ retinopathy, particularly in the parafoveal pattern.\u003c/p\u003e\u003cp\u003eWide field SD-OCT might be benefit for screening CQ/HCQ retinopathy in the Asian population. In our study, 61.5% (16 of 26 cases) of CQ/HCQ retinopathy were diagnosed based on VF defects, confirmed by abnormal signals in mfERG without any evidence of structural changes from SD-OCT and FAF. Among these cases, 10 of 16 cases (62.5%) were categorized as having a pericentral pattern. Comparison with previous study conducted by Marmor MF and Melles RB in California,\u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e found a 10% disparity between VF and SD-OCT findings in HCQ retinopathy with a parafoveal pattern, our study suggests that the higher prevalence of pericentral patterns in the Asian population may lead to the oversight of lesions at the periphery of SD-OCT. As a result, This concept is supported by a study conducted in South Korea by Seong Joon Ahn et al,\u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e\u003c/sup\u003e which demonstrated that 9-mm line scans from wide-field OCT detected HCQ retinopathy significantly better than 6-mm scans from SD-OCT.\u003c/p\u003e\u003cp\u003eThe SITA Faster 24-2C test offers the advantage of a shorter test duration compared to the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 (2.2 minutes versus 4.5 minutes; P\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Our study aligns with previous research, confirming the efficiency of the SITA Faster 24-2C, as it significantly reduces testing time compared to the SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 (155 versus 314 seconds).\u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e With regard to the SITA Faster 24-2C, several modifications were implemented to expedite this strategy,\u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e such as age-corrected starting stimulus intensities, a reduction in reversals at primary test points, utilization of the distribution of SITA Fast normal values, absence of a second check on perimetrically blind points, absence of false-negative catch trials, fixation verification through gaze tracking, and elimination of extra delay times. This benefit facilitates more frequent testing, reduces fatigue during testing, and thereby improves the ability to detect the disease. Based on the results of our study and the modifications of the SITA Faster 24-2C strategy, we recommend using the SITA Faster 24-2C for monitoring CQ/HCQ retinopathy in patients who are experienced with VF testing. This recommendation is due to the shorter test duration and reduced fatigue associated with this method.\u003c/p\u003e\u003cp\u003eThis study has several limitations that warrant consideration. First, the prevalence of CQ/HCQ retinopathy is relatively low in our study (26 of 75 cases, 34.7%). Additionally, 10 participants (11.8%) were excluded due to unreliable VF or evidence of other maculopathy, potentially impacting the power to discern differences in VF parameters between SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2. Second, VF, SD-OCT, and FAF results may differ based on the location and extent of the retinopathy. For instance, cases with early pericentral retinopathy may not show central scotomas.\u003csup\u003e\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e Therefore, our graders determined defects based on a literature review and their experiences. Last, our study design lacked a repeat test on the same day or within a short period to confirm the VF defects. Given the subjective nature of VF testing, confirmation testing could potentially reduce false positives and false negatives.\u003csup\u003e\u003cspan additionalcitationids=\"CR24\" citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eBoth the SITA Faster 24-2C and SITA Standard 24\u0026thinsp;\u0026minus;\u0026thinsp;2 tests are comparable in screening for CQ/HCQ retinopathy and show strongly positive agreement. However, the SITA Faster 24-2C offers the advantage of shorter test duration. Integrating the results with SD-OCT including wide field scanning, FAF, and mfERG helps clinicians in achieving a precise diagnosis. The addition of testing points within the central 10-degree radius does not enhance the detection of CQ/HCQ retinopathy in the Thai populations.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"EN-US\"\u003eACKNOWLEDGEMENTS \u0026amp; DISCLOSURES\u003c/span\u003e\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"EN-US\"\u003ea) Financial Support:\u0026nbsp;\u003c/span\u003e\u003c/strong\u003eRatchadapiseksompotch Fund, Graduate\u0026nbsp;Affairs, Faculty of\u0026nbsp;Medicine, Chulalongkorn University, Grant number\u0026nbsp;65/54\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"EN-US\"\u003eb) Financial Disclosures:\u003c/span\u003e\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cspan lang=\"EN-US\"\u003eThe authors declare no conflict of interest.\u003c/span\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u003cspan lang=\"EN-US\"\u003ec) Other Acknowledgements:\u003c/span\u003e\u003c/strong\u003e\u003cspan lang=\"EN-US\"\u003e\u0026nbsp;None\u003c/span\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eYusuf IH, Sharma S, Luqmani R, Downes SM. Hydroxychloroquine retinopathy. \u003cem\u003eEye (Lond)\u003c/em\u003e. Jun 2017;31(6):828-845. doi:10.1038/eye.2016.298\u003c/li\u003e\n\u003cli\u003eMelles RB, Marmor MF. The risk of toxic retinopathy in patients on long-term hydroxychloroquine therapy. \u003cem\u003eJAMA Ophthalmol\u003c/em\u003e. Dec 2014;132(12):1453-60. doi:10.1001/jamaophthalmol.2014.3459\u003c/li\u003e\n\u003cli\u003eMarmor MF, Kellner U, Lai TY, Melles RB, Mieler WF, American Academy of O. Recommendations on Screening for Chloroquine and Hydroxychloroquine Retinopathy (2016 Revision). \u003cem\u003eOphthalmology\u003c/em\u003e. Jun 2016;123(6):1386-94. doi:10.1016/j.ophtha.2016.01.058\u003c/li\u003e\n\u003cli\u003eMelles RB, Marmor MF. Pericentral retinopathy and racial differences in hydroxychloroquine toxicity. \u003cem\u003eOphthalmology\u003c/em\u003e. Jan 2015;122(1):110-6. doi:10.1016/j.ophtha.2014.07.018\u003c/li\u003e\n\u003cli\u003eVilainerun N HP. Patterns of Hydroxychloroquine and Chloroquine Retinopathy in Thai Patients. \u003cem\u003eThai J Ophthalmol\u003c/em\u003e. 2019;33(2):66-75. \u003c/li\u003e\n\u003cli\u003eGrillo LM, Wang DL, Ramachandran R, et al. The 24-2 Visual Field Test Misses Central Macular Damage Confirmed by the 10-2 Visual Field Test and Optical Coherence Tomography. \u003cem\u003eTransl Vis Sci Technol\u003c/em\u003e. Apr 2016;5(2):15. doi:10.1167/tvst.5.2.15\u003c/li\u003e\n\u003cli\u003eChakravarti T, Moghadam M, Proudfoot JA, Weinreb RN, Bowd C, Zangwill LM. Agreement Between 10-2 and 24-2C Visual Field Test Protocols for Detecting Glaucomatous Central Visual Field Defects. \u003cem\u003eJ Glaucoma\u003c/em\u003e. Jun 1 2021;30(6):e285-e291. doi:10.1097/IJG.0000000000001844\u003c/li\u003e\n\u003cli\u003eYamane MLM, Odel JG. Introducing the 24-2C Visual Field Test in Neuro-Ophthalmology. \u003cem\u003eJ Neuroophthalmol\u003c/em\u003e. Dec 1 2021;41(4):e606-e611. doi:10.1097/WNO.0000000000001157\u003c/li\u003e\n\u003cli\u003eGreenstein VC, Amaro-Quireza L, Abraham ES, Ramachandran R, Tsang SH, Hood DC. A comparison of structural and functional changes in patients screened for hydroxychloroquine retinopathy. \u003cem\u003eDoc Ophthalmol\u003c/em\u003e. Feb 2015;130(1):13-23. doi:10.1007/s10633-014-9474-6\u003c/li\u003e\n\u003cli\u003eMarmor MF. Comparison of screening procedures in hydroxychloroquine toxicity. \u003cem\u003eArch Ophthalmol\u003c/em\u003e. Apr 2012;130(4):461-9. doi:10.1001/archophthalmol.2011.371\u003c/li\u003e\n\u003cli\u003eMichaelides M, Stover NB, Francis PJ, Weleber RG. Retinal toxicity associated with hydroxychloroquine and chloroquine: risk factors, screening, and progression despite cessation of therapy. \u003cem\u003eArch Ophthalmol\u003c/em\u003e. Jan 2011;129(1):30-9. doi:10.1001/archophthalmol.2010.321\u003c/li\u003e\n\u003cli\u003ePhu J, Kalloniatis M. Ability of 24-2C and 24-2 Grids to Identify Central Visual Field Defects and Structure-Function Concordance in Glaucoma and Suspects. \u003cem\u003eAm J Ophthalmol\u003c/em\u003e. Nov 2020;219:317-331. doi:10.1016/j.ajo.2020.06.024\u003c/li\u003e\n\u003cli\u003eSu S, Callan T, Yu S, et al. Comparison of 24-2C SITA Standard and 24-2C SITA Faster. \u003cem\u003eInvestigative Ophthalmology \u0026amp; Visual Science\u003c/em\u003e. 2022;63(7):1267 \u0026ndash; A0407-1267 \u0026ndash; A0407. \u003c/li\u003e\n\u003cli\u003eBland JM, Altman DG. Statistical methods for assessing agreement between two methods of clinical measurement. \u003cem\u003eLancet\u003c/em\u003e. Feb 8 1986;1(8476):307-10. \u003c/li\u003e\n\u003cli\u003eCosta VP, Zangalli CS, Jammal AA, et al. 24-2 SITA Standard versus 24-2 SITA Faster in Perimetry-Naive Normal Subjects. \u003cem\u003eOphthalmol Glaucoma\u003c/em\u003e. Mar-Apr 2023;6(2):129-136. doi:10.1016/j.ogla.2022.08.006\u003c/li\u003e\n\u003cli\u003eHeijl A, Patella VM, Chong LX, et al. A New SITA Perimetric Threshold Testing Algorithm: Construction and a Multicenter Clinical Study. \u003cem\u003eAm J Ophthalmol\u003c/em\u003e. Feb 2019;198:154-165. doi:10.1016/j.ajo.2018.10.010\u003c/li\u003e\n\u003cli\u003eChoi EY, Li D, Fan Y, et al. Predicting Global Test-Retest Variability of Visual Fields in Glaucoma. \u003cem\u003eOphthalmol Glaucoma\u003c/em\u003e. Jul-Aug 2021;4(4):390-399. doi:10.1016/j.ogla.2020.12.001\u003c/li\u003e\n\u003cli\u003eKatz J, Sommer A. Screening for glaucomatous visual field loss. The effect of patient reliability. \u003cem\u003eOphthalmology\u003c/em\u003e. Aug 1990;97(8):1032-7. doi:10.1016/s0161-6420(90)32467-3\u003c/li\u003e\n\u003cli\u003eChen E, Brown DM, Benz MS, et al. Spectral domain optical coherence tomography as an effective screening test for hydroxychloroquine retinopathy (the \u0026quot;flying saucer\u0026quot; sign). \u003cem\u003eClin Ophthalmol\u003c/em\u003e. Oct 21 2010;4:1151-8. doi:10.2147/OPTH.S14257\u003c/li\u003e\n\u003cli\u003eMarmor MF, Melles RB. Disparity between visual fields and optical coherence tomography in hydroxychloroquine retinopathy. \u003cem\u003eOphthalmology\u003c/em\u003e. Jun 2014;121(6):1257-62. doi:10.1016/j.ophtha.2013.12.002\u003c/li\u003e\n\u003cli\u003eAhn SJ, Joung J, Lim HW, Lee BR. Optical Coherence Tomography Protocols for Screening of Hydroxychloroquine Retinopathy in Asian Patients. \u003cem\u003eAm J Ophthalmol\u003c/em\u003e. Dec 2017;184:11-18. doi:10.1016/j.ajo.2017.09.025\u003c/li\u003e\n\u003cli\u003eKim KE, Ryu SJ, Kim YH, Seo Y, Ahn SJ. Visual field examinations using different strategies in Asian patients taking hydroxychloroquine. \u003cem\u003eSci Rep\u003c/em\u003e. Aug 30 2022;12(1):14778. doi:10.1038/s41598-022-19048-0\u003c/li\u003e\n\u003cli\u003eKeltner JL, Johnson CA, Quigg JM, Cello KE, Kass MA, Gordon MO. Confirmation of visual field abnormalities in the Ocular Hypertension Treatment Study. Ocular Hypertension Treatment Study Group. \u003cem\u003eArch Ophthalmol\u003c/em\u003e. Sep 2000;118(9):1187-94. doi:10.1001/archopht.118.9.1187\u003c/li\u003e\n\u003cli\u003eKim J, Dally LG, Ederer F, et al. The Advanced Glaucoma Intervention Study (AGIS): 14. Distinguishing progression of glaucoma from visual field fluctuations. \u003cem\u003eOphthalmology\u003c/em\u003e. Nov 2004;111(11):2109-16. doi:10.1016/j.ophtha.2004.06.029\u003c/li\u003e\n\u003cli\u003eSchulzer M. Errors in the diagnosis of visual field progression in normal-tension glaucoma. \u003cem\u003eOphthalmology\u003c/em\u003e. Sep 1994;101(9):1589-94; discussion 1595. doi:10.1016/s0161-6420(94)31133-x\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"eye","isNatureJournal":false,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"eye","sideBox":"Learn more about [Eye](http://www.nature.com/eye/)","snPcode":"41433","submissionUrl":"https://mts-eye.nature.com/cgi-bin/main.plex","title":"Eye","twitterHandle":"@eye_journal","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-6769459/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6769459/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003ePurpose\u003c/strong\u003e To compare the SITA Standard 24-2 and SITA Faster 24-2C tests in patients with chloroquine/hydroxychloroquine (CQ/HCQ) retinopathy and those at high risk.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods\u003c/strong\u003e A prospective, cross-sectional study of 75 participants who underwent CQ/HCQ retinopathy screening using the SITA Standard 24-2, SITA Faster 24-2C, optical coherence tomography, fundus autofluorescence, and a dilated eye examination on the same day. Participants were categorized into retinopathy and non-retinopathy groups by graders. The agreement between the two visual field (VF) tests was assessed using Bland-Altman plots.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults\u003c/strong\u003e Among the 75 participants, 26 (34.67%) were diagnosed with CQ/HCQ retinopathy. Bland-Altman plots show good agreement in median deviation (MD), pattern standard deviation (PSD) and central mean sensitivity (CMS) between tests. The concordance coefficient wasat 0.89-0.93. Significant differences in MD, PSD, and CMS, were observed between the retinopathy and non-retinopathy groups for both VF tests (P\u0026lt;0.048). However, within each group, the results of both VF tests were comparable across all parameters (P=0.08-0.98), except for PSD in the retinopathy group. The SITA Faster 24-2C test had a significantly shorter testing duration.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions\u003c/strong\u003e The SITA Standard 24-2 and SITA Faster 24-2C tests showed similar efficacy and strongly positive agreement in screening for CQ/HCQ retinopathy. However, the SITA Faster 24-2C minimized the testing time. The addition of testing points within the central 10-degree field did not enhance the detection of CQ/HCQ retinopathy in the Thai population\u003c/p\u003e","manuscriptTitle":"Agreements between 24-2 and 24-2C Test Grids for Chloroquine/Hydroxychloroquine Retinopathy Patients and High-Risk Patients","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-15 06:41:42","doi":"10.21203/rs.3.rs-6769459/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"revise","date":"2025-11-11T09:06:14+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"This content is not available.","date":"2025-10-05T15:59:30+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewerAgreed","content":"This content is not available.","date":"2025-10-05T10:47:11+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewersInvited","content":"","date":"2025-10-01T09:21:11+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-06-05T14:21:17+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-05-29T13:33:22+00:00","index":"","fulltext":""},{"type":"submitted","content":"Eye","date":"2025-05-28T15:17:29+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"eye","isNatureJournal":false,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"eye","sideBox":"Learn more about [Eye](http://www.nature.com/eye/)","snPcode":"41433","submissionUrl":"https://mts-eye.nature.com/cgi-bin/main.plex","title":"Eye","twitterHandle":"@eye_journal","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"826c33da-3f5a-4753-b931-75b2b406cdb2","owner":[],"postedDate":"October 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":55621841,"name":"Health sciences/Diseases/Eye diseases/Retinal diseases"},{"id":55621842,"name":"Health sciences/Medical research/Outcomes research"},{"id":55621843,"name":"Health sciences/Health care/Diagnosis/Physical examination"}],"tags":[],"updatedAt":"2026-05-05T07:11:02+00:00","versionOfRecord":{"articleIdentity":"rs-6769459","link":"https://doi.org/10.1038/s41433-026-04462-9","journal":{"identity":"eye","isVorOnly":false,"title":"Eye"},"publishedOn":"2026-05-05 04:00:00","publishedOnDateReadable":"May 5th, 2026"},"versionCreatedAt":"2025-10-15 06:41:42","video":"","vorDoi":"10.1038/s41433-026-04462-9","vorDoiUrl":"https://doi.org/10.1038/s41433-026-04462-9","workflowStages":[]},"version":"v1","identity":"rs-6769459","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6769459","identity":"rs-6769459","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}