Mapping the spatial distribution of primary and secondary PM2.5 in a multi-industrial city by combining monitoring and modeling results.

Industrial cities are strongly influenced by primary emissions of PM2.5 from local industries. In addition, gaseous precursors, such as sulfur oxides (SOX), nitrogen oxides (NOX), and volatile organic compounds (VOCs), emitted from industrial sources, undergo conversion into secondary inorganic and organic aerosols (SIAs and SOAs). In this study, the spatial distributions of primary and secondary PM2.5 in Ulsan, the largest industrial city in South Korea, were visualized. PM2.5 components (ions, carbons, and metals) and PM2.5 precursors (SO2, NO2, NH3, and VOCs) were measured to estimate the concentrations of secondary inorganic ions (SO42-, NO3-, and NH4+) and secondary organic aerosol formation potential (SOAFP). The spatial distributions of SIAs and SOAs were then plotted by combining atmospheric dispersion modeling, receptor modeling, and monitoring data. Spatial distribution maps of primary and secondary PM2.5 provide fundamental insights for formulating management policies in different districts of Ulsan. For instance, among the five districts in Ulsan, Nam-gu exhibited the highest levels of primary PM2.5 and secondary nitrate. Consequently, controlling both PM2.5 and NO2 emissions becomes essential in this district. The methodology developed in this study successfully identified areas with dominant contributions from both primary emissions and secondary formation. This approach can be further applied to prioritize control measures during periods of elevated PM levels in other industrial cities.

Prognostic factors of first-onset optic neuritis based on diagnostic criteria and antibody status: a multicentre analysis of 427 eyes.

BACKGROUND: Optic neuritis (ON) prognosis is influenced by various factors including attack severity, underlying aetiologies, treatments and consequences of previous episodes. This study, conducted on a large cohort of first ON episodes, aimed to identify unique prognostic factors for each ON subtype, while excluding any potential influence from pre-existing sequelae. METHODS: Patients experiencing their first ON episodes, with complete aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibody testing, and clinical data for applying multiple sclerosis (MS) diagnostic criteria, were enrolled. 427 eyes from 355 patients from 10 hospitals were categorised into four subgroups: neuromyelitis optica with AQP4 IgG (NMOSD-ON), MOG antibody-associated disease (MOGAD-ON), ON in MS (MS-ON) or idiopathic ON (ION). Prognostic factors linked to complete recovery (regaining 20/20 visual acuity (VA)) or moderate recovery (regaining 20/40 VA) were assessed through multivariable Cox regression analysis. RESULTS: VA at nadir emerged as a robust prognostic factor for both complete and moderate recovery, spanning all ON subtypes. Early intravenous methylprednisolone (IVMP) was associated with enhanced complete recovery in NMOSD-ON and MOGAD-ON, but not in MS-ON or ION. Interestingly, in NMOSD-ON, even a slight IVMP delay in IVMP by >3 days had a significant negative impact, whereas a moderate delay up to 7-9 days was permissible in MOGAD-ON. Female sex predicted poor recovery in MOGAD-ON, while older age hindered moderate recovery in NMOSD-ON and ION. CONCLUSION: This comprehensive multicentre analysis on first-onset ON unveils subtype-specific prognostic factors. These insights will assist tailored treatment strategies and patient counselling for ON.

Risk of central nervous system demyelinating attack or optic neuritis recurrence after pediatric optic neuritis in Korea.

PURPOSE: To investigate the rate of development of symptomatic central nervous system (CNS) demyelinating attacks or recurrent optic neuritis (ON) after the first episode of ON and its risk factors for Korean pediatric patients. METHODS: This multicenter retrospective cohort study included the patients under 18 years of age (n=132) diagnosed with ON without previous or simultaneous CNS demyelinating diseases. We obtained the clinical data including the results of neuro-ophthalmological examinations, magnetic resonance images (MRIs), antibody assays, and laboratory tests. We investigated the chronological course of demyelinating disease with respect to the occurrence of neurological symptoms and/or signs, and calculated the 5-year cumulative probability of CNS demyelinating disease or ON recurrence.  RESULTS: During the follow-up period (63.1±46.7 months), 18 patients had experienced other CNS demyelinating attacks, and the 5-year cumulative probability was 14.0±3.6%. Involvement of the extraorbital optic nerve or optic chiasm and asymptomatic lesions on the brain or spinal MRI at initial presentation were significant predictors for CNS demyelinating attack after the first ON. The 5-year cumulative probability of CNS demyelinating attack was 44.4 ± 24.8% in the AQP4-IgG group, 26.2±11.4% in the MOG-IgG group, and 8.7±5.9% in the double-negative group (P=0.416). Thirty-two patients had experienced a recurrence of ON, and the 5-year cumulative probability was 24.6±4.0%. In the AQP4-IgG group, the 5-year cumulative probability was 83.3±15.2%, which was significantly higher than in the other groups (P<0.001). CONCLUSIONS: A careful and multidisciplinary approach including brain/spinal imaging and antibody assay can help predict further demyelinating attacks in pediatric ON patients.

Factors associated with changes in horizontal deviation after inferior oblique weakening surgery.

BACKGROUND/AIMS: To identify the factors affecting postoperative horizontal deviation following isolated inferior oblique (IO) weakening surgery. METHODS: The medical records of patients who had undergone isolated IO weakening surgery between February 2010 and September 2021, with a minimum follow-up period of 6 months, were retrospectively reviewed. Patients were divided into two groups, eso-shift, and non-eso-shift, based on the change in horizontal deviation at postoperative 6 months. Eso-shift or exo-shift was defined as a change of 2Δ or more. RESULTS: A total of 77 patients were included. Among them, 49 patients (63.6%) showed changes in horizontal deviation: 37 (48.0%) eso-shift, 12 (15.6%) exo-shift. Twenty-eight patients (36.4%) showed no change in alignment. The eso-shift group showed the following characteristics compared to the non-eso-shift group: older age (P < 0.001), higher proportion of patients with preoperative exo-deviation (P < 0.001), and greater preoperative hypertropia in primary gaze (P < 0.001), down gaze (P = 0.031), ipsilateral gaze (P < 0.001), and ipsilateral head tilt (P = 0.002). Regarding the postoperative changes in horizontal deviation based on prior horizontal strabismus, patients with preoperative exo-deviation showed a statistically significant eso-shift. The patients with prior eso-deviation tended toward exo-shift, while those without prior horizontal deviation rarely changed. CONCLUSION: Changes in postoperative horizontal deviation are associated with preoperative horizontal and vertical deviation, which might result from changes in the rectus muscle due to oblique muscle dysfunction. Also, this study suggests that isolated IO weakening surgery could effectively correct small-angle horizontal deviation in patients with inferior oblique overaction (IOOA) and horizontal strabismus.

Passive air sampling of VOCs, O3, NO2, and SO2 in the large industrial city of Ulsan, South Korea: spatial-temporal variations, source identification, and ozone formation potential.

Concerns about volatile organic compounds (VOCs) have increased due to their toxicity and secondary reaction with nitrogen oxides (NOX) to form ozone (O3). In this study, passive air sampling of VOCs, O3, NO2, and SO2 was conducted in summer, fall, winter, and spring from 2019 to 2020 at six industrial and ten urban sites in Ulsan, the largest industrial city in South Korea. Over the entire sampling period, the concentration of toluene (mean: 8.75 µg/m3) was the highest of the 50 target VOCs, followed by m,p-xylenes (4.52 µg/m3), ethylbenzene (4.48 µg/m3), 3-methylpentane (4.40 µg/m3), and n-octane (4.26 µg/m3). Total (Σ50) VOC levels did not statistically differ between seasons, indicating that large amounts of VOCs are emitted into the atmosphere throughout the year. On the other hand, O3, NO2, and SO2 exhibited strong seasonal variation depending on the meteorological conditions and emission sources. The spatial distribution of Σ50 VOCs, NO2, and SO2 indicated that industrial complexes were major sources in Ulsan, while O3 had the opposite spatial distribution. Using a positive matrix factorization model, five major sources were identified, with industrial effects dominant. Aromatic compounds, such as m,p,o-xylenes, toluene, and 1,2,4-trimethylbenzene, significantly contributed to O3 formation. The VOC/NO2 ratio and O3 concentrations suggested that reducing VOC emissions is more effective than reducing NO2 emissions in terms of preventing the secondary formation of O3. The findings of this study allow for a better understanding of the relationship between VOCs, O3, NO2, and SO2 in industrial cities.

Non-Arteritic Ischemic Optic Neuropathy Following COVID-19 Vaccination in Korea: A Case Series.

BACKGROUND: To report the clinical manifestations of non-arteritic anterior ischemic optic neuropathy (NAION) cases after coronavirus disease 2019 (COVID-19) vaccination in Korea. METHODS: This multicenter retrospective study included patients diagnosed with NAION within 42 days of COVID-19 vaccination. We collected data on vaccinations, demographic features, presence of vascular risk factors, ocular findings, and visual outcomes of patients with NAION. RESULTS: The study included 16 eyes of 14 patients (6 men, 8 women) with a mean age of 63.5 ± 9.1 (range, 43-77) years. The most common underlying disease was hypertension, accounting for 28.6% of patients with NAION. Seven patients (50.0%) had no vascular risk factors for NAION. The mean time from vaccination to onset was 13.8 ± 14.2 (range, 1-41) days. All 16 eyes had disc swelling at initial presentation, and 3 of them (18.8%) had peripapillary intraretinal and/or subretinal fluid with severe disc swelling. Peripapillary hemorrhage was found in 50% of the patients, and one (6.3%) patient had peripapillary cotton-wool spots. In eight fellow eyes for which we were able to review the fundus photographs, the horizontal cup/disc ratio was less than 0.25 in four eyes (50.0%). The mean visual acuity was logMAR 0.6 ± 0.7 at the initial presentation and logMAR 0.7 ± 0.8 at the final visit. CONCLUSION: Only 64% of patients with NAION after COVID-19 vaccination have known vascular and ocular risk factors relevant to ischemic optic neuropathy. This suggests that COVID-19 vaccination may increase the risk of NAION. However, overall clinical features and visual outcomes of the NAION patients after COVID-19 vaccination were similar to those of typical NAION.

Refractive changes after strabismus surgery in patients with intermittent exotropia.

OBJECTIVES: To evaluate the long-term refractive changes after horizontal muscle surgery in patients with intermittent exotropia and investigate the correlation between changes in the postoperative refractive error and clinical factors. METHODS: We retrospectively reviewed the clinical data of patients aged < 15 years who underwent unilateral strabismus surgery (lateral rectus recession and medial rectus resection [RR, n = 47], lateral rectus recession and medial rectus plication [RP, n = 81], or lateral rectus recession [LRc, n = 68]). Preoperative and postoperative refractive errors up to four years after surgery were recorded. A mixed model was applied to compare the refractive error between the operated and fellow eyes and identify the factors associated with postoperative refractive changes. RESULTS: The mean age at surgery was 7.5±2.4years, and girls accounted for 56.1% of the study population. There was no significant difference in the change in the spherical equivalent of refractive error between both eyes throughout the postoperative period. In contrast, the operated eyes consistently and significantly showed higher cylindrical power in with-the-rule astigmatism by 0.25D than in fellow eyes. Age, sex, and preoperative refractive error were not correlated with changes in postoperative astigmatism. Meanwhile, the type of surgery showed a significant interaction with the astigmatism changes. RP had less effect on the changes in astigmatism than RR and LRc (p = 0.001 and p = 0.022, respectively). CONCLUSIONS: Horizontal muscle surgery has no long-term effect on the change in the spherical equivalent. However, mild with-the-rule astigmatism is induced and sustained after surgery, and the type of surgery affects the postoperative change of astigmatism.

Ocular motility disorders following coronavirus disease-19 vaccination.

PURPOSE: To describe clinical manifestations and short-term prognosis of ocular motility disorders following coronavirus disease-2019 (COVID-19) vaccination. METHODS: Ocular motility disorders were diagnosed by clinical assessment, high-resolution magnetic resonance imaging, and laboratory testing. Clinical manifestations, short-term prognosis, and rate of complete recovery were analyzed. RESULTS: Sixty-three patients (37 males, 26 females) with a mean age of 61.6 ± 13.3 years (range, 22-81 years) were included in this study. Among 61 applicable patients with sufficient information regarding medical histories, 38 (62.3%) had one or more significant underlying past medical histories including vasculopathic risk factors. The interval between initial symptoms and vaccination was 8.6 ± 8.2 (range, 0-28) days. Forty-two (66.7%), 14 (22.2%), and 7 (11.1%) patients developed symptoms after the first, second, and third vaccinations, respectively. One case of internuclear ophthalmoplegia, 52 cases of cranial nerve palsy, two cases of myasthenia gravis, six cases of orbital diseases (such as myositis, thyroid eye disease, and IgG-related orbital myopathy), and two cases of comitant vertical strabismus with acute onset diplopia were found. Among 42 patients with follow-up data (duration: 62.1 ± 40.3 days), complete improvement, partial improvement, no improvement, and exacerbation were shown in 20, 15, 3, and 4 patients, respectively. CONCLUSION: This study provided various clinical features of ocular motility disorders following COVID-19 vaccination. The majority of cases had a mild clinical course while some cases showed a progressive nature. Close follow-up and further studies are needed to elucidate the underlying mechanisms and long-term prognosis.

Characteristics of Optic Neuritis in South Korean Children and Adolescents: A Retrospective Multicenter Study.

Purpose: To analyze the clinical characteristics and prognosis of optic neuritis (ON) in pediatric patients aged <19 years in South Korea. Methods: This multicenter retrospective cohort study included 127 pediatric patients (median age: 10.3 (IQR: 7.3-14.2) years; female, 62.2%) who experienced ON for the first time between January 2004 and January 2018, with data obtained from five tertiary university-based hospitals in Korea. When ON was bilateral, the worse eye was selected for analysis. The baseline clinical characteristics and prognoses of patients, as well as the associations between these parameters, were analyzed. Results: The baseline clinical characteristics of the patients were as follows: best-corrected visual acuity (BCVA) < 20/200, 65.9%; pain on eye movement, 47.2%; optic disc swelling, 66.9%; and bilateral involvement, 41.7%. Among 101 patients who were followed up for ≥6 months, 48 (47.5%), 12 (11.9%), 19 (18.8%), 13 (12.9%), and 9 (8.9%) had been diagnosed with isolated ON, recurrent ON, multiple sclerosis (MS), neuromyelitis optica spectrum disorder (NMOSD), and acute disseminated encephalomyelitis (ADEM)-related ON, respectively. At the latest visit, 81.9% and 71.1% had achieved BCVA of ≥20/40 and ≥ 20/25, respectively. Only disc swelling at presentation was associated with poor baseline BCVA (coefficient: 0.31, P=0.004) and greater improvement in BCVA (coefficient: 0.49, P = 0.001P=0.001); there were no significant associations between the baseline factors and final BCVA. Conclusions: This study demonstrated pediatric ON-related clinical characteristics and visual outcomes in South Korea. Within this cohort, in about 40.6% of patients, ON was associated with other demyelinating diseases, namely, MS, NMOSD, and ADEM.

Characteristics of volatile organic compounds in the metropolitan city of Seoul, South Korea: Diurnal variation, source identification, secondary formation of organic aerosol, and health risk.

Atmospheric volatile organic compounds (VOCs) in Seoul, the capital of South Korea, have attracted increased attention owing to their emission, secondary formation, and human health risk. In this study, we collected 24 hourly samples once a month at an urban site in Seoul for a year (a total of 288 samples) using a sequential tube sampler. Analysis results revealed that toluene (9.08 ± 8.99 µg/m3) exhibited the highest annual mean concentration, followed by ethyl acetate (5.55 ± 9.09 µg/m3), m,p-xylenes (2.79 ± 4.57 µg/m3), benzene (2.37 ± 1.55 µg/m3), ethylbenzene (1.81 ± 2.27 µg/m3), and o-xylene (0.91 ± 1.47 µg/m3), indicating that these compounds accounted for 77.8-85.6% of the seasonal mean concentrations of the total (Σ59) VOCs. The concentrations of the Σ59 VOCs were statistically higher in spring and winter than in summer and fall because of meteorological conditions, and the concentrations of individual VOCs were higher during the daytime than nighttime owing to higher human activities during the daytime. The conditional bivariate probability function and concentration weighted trajectory analysis results suggested that domestic effects (e.g., vehicular exhaust and solvents) exhibited a dominant effect on the presence of VOCs in Seoul, as well as long-range atmospheric transport of VOCs. Further, the most important secondary organic aerosol formation potential (SOAFP) compounds included benzene, toluene, ethylbenzene, and m,p,o-xylenes, and the total SOAFP of nine VOCs accounted for 5-29% of the seasonal mean PM2.5 concentrations. The cancer and non-cancer risks of the selected VOCs were below the tolerable (1 × 10-4) and acceptable (Hazard quotient: HQ < 1) levels, respectively. Overall, this study highlighted the feasibility of the sequential sampling of VOCs and hybrid receptor modeling to further understand the source-receptor relationship of VOCs.

Long-Term Visual Prognosis in Patients With Aquaporin-4-Immunoglobulin G-Positive Neuromyelitis Optica Spectrum Disorder.

BACKGROUND: To identify the factors associated with visual prognosis for functional and structural outcomes of optic neuritis (ON) in patients with aquaporin-4-immunoglobulin (AQP4-IgG)-positive neuromyelitis optica spectrum disorder (NMOSD). METHODS: We included the eyes that experienced at least 1 episode of ON and were followed for at least 2 years after the first attack of ON in patients with AQP4-IgG-positive NMOSD. We performed a retrospective review of clinical data, including ophthalmological examination and orbital MRI, of 34 eyes of 22 patients. Functional outcomes were measured as final visual acuity, visual field index, and mean deviation and structural outcomes as final retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness. RESULTS: The mean age at onset of the first ON was 42.7 ± 13.7, and all patients were female. The poor visual acuity was significantly associated with the worse final visual acuity and thinner RNFL and GCIPL. Older age also showed a negative correlation with RNFL thickness. The number of attacks was not statistically significant for functional and structural outcomes. The lesion involving the intracanalicular optic nerve to the chiasm on orbital MRI showed worse visual acuity and a thinner GCIPL. Rapid high-dose intravenous methylprednisolone pulse therapy within 3 days was statistically significant, with better visual acuity and more preserved GCIPL thickness. CONCLUSIONS: Our results indicate that the severity of ON rather than the number of recurrences might be critical for the visual prognosis of patients with AQP4-IgG-positive NMOSD. Rapid treatment within 3 days may improve visual outcomes, and a younger age at onset may have better visual outcomes.

Myelin Oligodendrocyte Glycoprotein-Immunoglobulin G in the CSF: Clinical Implication of Testing and Association With Disability.

BACKGROUND AND OBJECTIVE: To investigate the clinical relevance of CSF myelin oligodendrocyte glycoprotein-immunoglobulin G (MOG-IgG) testing in a large multicenter cohort. METHODS: In this multicenter cohort study, paired serum-CSF samples from 474 patients with suspected inflammatory demyelinating disease (IDD) from 11 referral hospitals were included. After serum screening, patients were grouped into seropositive myelin oligodendrocyte glycoprotein antibody associated disease (MOGAD, 31), aquaporin-4-IgG-positive neuromyelitis optica spectrum disorder (AQP4-IgG + NMOSD, 60), other IDDs (217), multiple sclerosis (MS, 45), and non-IDDs (121). We then screened CSF for MOG-IgG and compared the clinical and serologic characteristics of patients uniquely positive for MOG-IgG in the CSF to seropositive patients with MOGAD. RESULTS: Nineteen patients with seropositive MOGAD (61.3%), 9 with other IDDs (CSF MOG + IDD, 4.1%), 4 with MS (8.9%), but none with AQP4-IgG + NMOSD nor with non-IDDs tested positive in the CSF for MOG-IgG. The clinical, pathologic, and prognostic features of patients uniquely positive for CSF MOG-IgG, with a non-MS phenotype, were comparable with those of seropositive MOGAD. Intrathecal MOG-IgG synthesis, observed from the onset of disease, was shown in 12 patients: 4 of 28 who were seropositive and 8 who were uniquely CSF positive, all of whom had involvement of either brain or spinal cord. Both CSF MOG-IgG titer and corrected CSF/serum MOG-IgG index, but not serum MOG-IgG titer, were associated with disability, CSF pleocytosis, and level of CSF proteins. DISCUSSION: CSF MOG-IgG is found in IDD other than MS and also in MS. In IDD other than MS, the CSF MOG-IgG positivity can support the diagnosis of MOGAD. The synthesis of MOG-IgG in the CNS of patients with MOGAD can be detected from the onset of the disease and is associated with the severity of the disease. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that the presence of CSF MOG-IgG can improve the diagnosis of MOGAD in the absence of an MS phenotype, and intrathecal synthesis of MOG-IgG was associated with increased disability.

Efficacy and Safety of 8 Atropine Concentrations for Myopia Control in Children: A Network Meta-Analysis.

TOPIC: Comparative efficacy and safety of different concentrations of atropine for myopia control. CLINICAL RELEVANCE: Atropine is known to be an effective intervention to delay myopia progression. Nonetheless, no well-supported evidence exists yet to rank the clinical outcomes of various concentrations of atropine. METHODS: We searched PubMed, EMBASE, Cochrane Central Register of Controlled Trials, the World Health Organization International Clinical Trials Registry Platform, and ClinicalTrials.gov on April 14, 2021. We selected studies involving atropine treatment of at least 1 year's duration for myopia control in children. We performed a network meta-analysis (NMA) of randomized controlled trials (RCTs) and compared 8 atropine concentrations (1% to 0.01%). We ranked the atropine concentrations for the corresponding outcomes by P score (estimate of probability of being best treatment). Our primary outcomes were mean annual changes in refraction (diopters/year) and axial length (AXL; millimeters/year). We extracted data on the proportion of eyes showing myopia progression and safety outcomes (photopic and mesopic pupil diameter, accommodation amplitude, and distance and near best-corrected visual acuity [BCVA]). RESULTS: Thirty pairwise comparisons from 16 RCTs (3272 participants) were obtained. Our NMA ranked the 1%, 0.5%, and 0.05% atropine concentrations as the 3 most beneficial for myopia control, as assessed for both primary outcomes: 1% atropine (mean differences compared with control: refraction, 0.81 [95% confidence interval (CI), 0.58-1.04]; AXL, -0.35 [-0.46 to -0.25]); 0.5% atropine (mean differences compared with control: refraction, 0.70 [95% CI, 0.40-1.00]; AXL, -0.23 [-0.38 to -0.07]); 0.05% atropine (mean differences compared with control: refraction, 0.62 [95% CI, 0.17-1.07]; AXL, -0.25 [-0.44 to -0.06]). In terms of myopia control as assessed by relative risk (RR) for overall myopia progression, 0.05% was ranked as the most beneficial concentration (RR, 0.39 [95% CI, 0.27-0.57]). The risk for adverse effects tended to rise as the atropine concentration was increased, although this tendency was not evident for distance BCVA. No valid network was formed for near BCVA. DISCUSSION: The ranking probability for efficacy was not proportional to dose (i.e., 0.05% atropine was comparable with that of high-dose atropine [1% and 0.5%]), although those for pupil size and accommodation amplitude were dose related.

Longitudinal course of consecutive esotropia in children following surgery for basic-type intermittent exotropia.

PURPOSE: To evaluate the longitudinal course of consecutive esotropia following surgery for basic-type intermittent exotropia. METHODS: Patients who underwent surgery (bilateral lateral rectus muscle recession [BLR] or unilateral lateral rectus muscle recession-medial rectus muscle resection [RR]) for the treatment of intermittent exotropia between 2011 and 2017 with a minimum follow-up period of 2 years were retrospectively reviewed. When esodeviation occurred later in patients with orthotropia or exodeviation at postoperative month 1, it was defined as delayed-onset consecutive esotropia. The number of patients with esodeviation at every follow-up and characteristics of patients were evaluated. RESULTS: A total of 336 patients (6.2 ± 2.1 years; 236 in the BLR group and 100 in the RR group) were included. After surgery, postoperative esodeviation decreased mostly during the 1st postoperative month in both groups. At postoperative year 2, there were 28 patients (8.3%) with consecutive esotropia: six in the RR group and 22 in the BLR group. Among the 284 patients with orthotropia or exodeviation at postoperative month 1, there were 13 patients with delayed-onset consecutive esotropia; they presented larger preoperative angle of exodeviation, poorer stereopsis, younger at the time of surgery and associated with the types of surgeries for exotropia. CONCLUSIONS: In patients with consecutive esotropia, the angle of esodeviation decreased and patching/prismatic correction helped achieve the good surgical outcomes. However, delayed-onset consecutive esotropia and persistent esotropia also presented, requiring the reoperation. Therefore, postoperative alignment should be carefully monitored after surgery for intermittent exotropia.

Management of patients with small-angle esotropia and subnormal stereopsis using Fresnel prism.

PURPOSE: Monofixation syndrome (MFS) is a specific subnormal binocular vision status, either with or without a small deviation. Patients with MFS have a tendency to maintain stable ocular alignment. Correction of refractive errors and occlusion are considered as treatment option for amblyopia, and the status of MFS could be changed with long-term follow-up. The purpose of this study is to evaluate whether a Fresnel prism affected the visual acuity, angle of deviation, and sensory status in small-angle esotropia with subnormal stereopsis presenting with MFS features. METHODS: Patients with small-angle esotropia within 8 prism diopters (PD) on the simultaneous prism and cover test from 2010 to 2019 were reviewed. Patients with subnormal stereopsis defined as more than 100 s of arc (arcsec) and with the central suppression with peripheral fusion were only included. A Fresnel prism was applied to the dominant eye, and the minimum follow-up period after Fresnel prism treatment was 24 months. We assessed patient clinical characteristics, course and response to therapy including visual acuity, angle of deviation, and stereopsis. RESULTS: Twenty patients with a mean age of 5.5 ± 1.4 years were included. The mean duration of Fresnel prism treatment was 15.3 ± 10.3 months. After 50.7 ± 17.2 months of follow-up, VA of the non-dominant eye was changed from 0.26 ± 0.20 logMAR to 0.07 ± 0.17 logMAR (P < .001). The initial stereoacuities were 3.54 ± 0.27 log arcsec, ranged from 6000 to 400 arcsec. After the treatment with Fresnel prism, the final stereoacuities were 3.09 ± 0.58 log arcsec, ranged from 6000 to 100 arcsec (P = .001); nine patients (45%) improved stereoacuity more than two octaves. No changes in the angle of deviation or a change of fixation were observed. CONCLUSIONS: After use of Fresnel prism, there was some improvement in visual acuity and stereopsis in patients with MFS features. Following occlusion and refractive correction, management using Fresnel prism could be attempted in small-angle esotropic patients with amblyopia or subnormal stereopsis.

Investigation of transient eye closure evoked with bright light in the patients with intermittent exotropia.

BACKGROUND: This study aimed to present a simple method for evaluating transient eye closure (TEC) evoked by bright light and find the agreement between TEC and photosensitivity. We also assessed the associated factors with TEC in the patients with intermittent exotropia (IXT). METHODS: In this retrospective study, IXT patients were exposed to different brightness: darkness, low-intensity white light, and high-intensity white light using a near-infrared camera vision monitor system (Mon CV3, Metrovision, France). TEC was considered to be present if the subject closed his or her eyes immediately, and for more than half of the scotopic lid fissure distance in response to the high-intensity or low-intensity photopic stimulus of light, compared with lid fissure distance in the scotopic phase. We assessed the presence of photosensitivity using a questionnaire and evaluated the agreement between TEC and photosensitivity. We also investigated the sensory fusion, motor fusion, and pupil dynamic components for the existence of TEC in IXT patients. RESULTS: Sixty-one patients with IXT were included. With the new method to evaluate TEC under different light intensities, 27 (44.3%) of the 61 IXT patients showed TEC, and 34 (55.7%) did not demonstrate TEC. TEC under high-intensity white light had a strong correlation with self-reporting photosensitivity (r = 0.77). The smaller angle of deviation at near was associated with the presence of TEC, with statistical significance (p = 0.04). Normal sensory status at a distance was significantly associated with TEC (p <  0.01). Multivariate analysis using multiple logistic regression analysis showed that normal sensory status was significantly associated with TEC (p = 0.02). CONCLUSIONS: The test using a near-infrared camera vision monitor system was a simple and objective tool in identifying TEC evoked by bright light. The presence of TEC strongly correlated with self-reporting photosensitivity in patients with IXT. However, TEC may be an independent phenomenon with motor alignment, stereopsis, and pupil reflex pathway in patients with IXT.

Visual outcomes and associated factors of primary congenital glaucoma in children.

PURPOSE: We evaluated the long-term visual outcomes in children with primary congenital glaucoma and determined the factors associated with the final visual outcomes. METHODS: Medical records of children with primary congenital glaucoma between 2005 and 2016, seen at Seoul National University Children's Hospital in South Korea, were reviewed. The minimum follow-up period after surgery for primary congenital glaucoma was 3 years. Visual acuity (VA) was categorized into good (≧20/70) and poor (< 20/70). Factors including age, VA, refractive errors, intraocular pressure (IOP), laterality, and cup-to-disc (C/D) ratio were compared between the groups. RESULTS: A total of 71 eyes of 44 patients were included. The patients' age at the time of surgery was 14.7 ± 12.2 months. The mean IOP was 28.3 ± 7.0 mmHg. During 6.7 ± 2.7 years of mean follow-up after surgery, 39 eyes (54.9%) needed occlusion treatment. After occlusion, patients with lower IOP values, lesser additional surgeries, reversal of optic disc cupping, and better initially measured VA achieved a better visual outcome. At the final assessment, the mean age was 7.8 ± 2.6 years, and the mean VA gain was 15.0 ± 19.4 letters. There were 44 eyes (62.0%) with VA ≧20/70. CONCLUSIONS: In children with primary congenital glaucoma, IOP control and the optic disc configuration over time are important factors associated with visual outcome. Regular follow-up and correction of refractive errors-along with occlusion for those with difference in VA between the two eyes-might be helpful for achieving better visual outcomes.

Outcomes of using Bangerter foils for the treatment of residual amblyopia following patching therapy.

PURPOSE: To evaluate the effectiveness of additional treatment using Bangerter foil (BF) for children with residual amblyopia. METHODS: Patients with residual amblyopia who were treated with BF between 2015 and 2020 were reviewed. Residual amblyopia was defined as no further improvement in vision following patching therapy for at least 6 months. BF that corresponds to the VA of the amblyopic eye was applied to the spectacle lens of the fellow eye. Patients were divided into two groups: group A, which included patients treated with BF alone, and group B, which included patients treated with BF and a head-mounted display. After at least 2 months of treatment, baseline and final VA and stereoacuity were compared. RESULTS: Seventy-four patients with a mean age of 8.0 ± 1.6 years at the time of BF treatment were included. The mean duration of the BF treatment was 10.4 ± 5.6 months. After a mean follow-up period of 24.9 ± 11.9 months after BF treatment, the median (IQR) VA of the amblyopic eye changed from 0.20 (0.15-0.40) LogMAR to 0.10 (0.04-0.20) LogMAR (P = 0.001). The median (IQR) stereoacuity changed from 3.19 (2.53-3.75) log arcsec to 2.60 (2.15-3.48) log arcsec (P = 0.001). The number of patients improved vision by 0.2 LogMAR or more lines was 18 patients (30%) for group A and 3 patients (23%) for group B. The VA of the amblyopic eye before BF treatment was significantly associated with vision improvement. CONCLUSION: BF can be considered an alternative treatment plan to provide further benefit for children with residual amblyopia.