Oxygen use in Atacama large millimeter and submillimeter (ALMA) arrays in Chajnantor valley at 5050 m / Uso de oxígeno en Atacama large millimeter and submillimeter (ALMA) en el valle de Chajnantor a 5050 m

The Chilean workforce has over 200,000 people that are intermittently exposed to altitudes over 4000 m. In 2012, the Ministry of Health provided a technical guide for high altitude workers that included a series of actions to mitigate the effects of hypoxia. Previous studies have shown the positive effect of oxygen enrichment at high altitudes. The Atacama Large Millimeter / submillimeter Arrays (ALMA) radiotelescope operate at 5,050 m (Array Operation Site, AOS) and is the only place in the world where Pressure Swing Adsorption (PSA) and Liquid Oxygen technologies have been installed at a large scale. Here we discuss our experience using oxygen supplementation at ALMA, to prevent the malaise and/or risks associated with exposure at 5,050 m. Antenna operators experienced chronic intermittent hypobaric hypoxia (CIHH, shiftwork 8 days HA*6 days rest SL) over 4 years. Studies to define normal O2 saturation values were performed in OSF and AOS by continuous recording during the shift. The outcomes showed no differences between production procedures (PSA or Liquid oxygen) in regulating oxygen availability at AOS facilities. As a result, big-scale installations have difficulties reaching the appropriate oxygen concentration due to leaks in high mobility areas. In addition, the PSA plant requires adequation and maintenance to operate at a very high altitude.

La fuerza laboral chilena cuenta con más de 200.000 personas que están expuestas intermitentemente a altitudes superiores a los 4000 m. En 2012, el Ministerio de Salud entregó una guía técnica para trabajadores de altura que incluía una serie de acciones para mitigar los efectos de la hipoxia. Estudios anteriores han demostrado el efecto positivo del enriquecimiento de oxígeno en altitudes elevadas. El radiotelescopio Atacama Large Millimeter/submillimeter Arrays (ALMA) opera a 5.050 m (Array Operation Site, AOS) y es el único lugar en el mundo donde se han instalado tecnologías de adsorción por cambio de presión (PSA) y oxígeno líquido a gran escala. Aquí discutimos nuestra experiencia usando suplementos de oxígeno en ALMA, para prevenir el malestar y/o los riesgos asociados con la exposición a 5.050 m. Los operadores de antena experimentaron hipoxia hipobárica intermitente crónica (CIHH, trabajo por turnos 8 días HA*6 días descanso SL) durante 4 años. Se realizaron estudios para definir valores normales de saturación de O2 en OSF y AOS mediante registro continuo durante el turno. Los resultados no mostraron diferencias entre los procedimientos de producción (PSA u oxígeno líquido) en la regulación de la disponibilidad de oxígeno en las instalaciones de AOS. Como resultado, las instalaciones a gran escala tienen dificultades para alcanzar la concentración de oxígeno adecuada debido a fugas en áreas de alta movilidad. Además, la planta de PSA requiere de adecuación y mantenimiento para operar a gran altura.

Risk Factors Associated with the Recurrence of Amblyopia after Successful Treatment

PURPOSE: We sought factors affecting amblyopia recurrence after successful treatment.METHODS: We included 117 patients with amblyopia. Patients were divided into recurrence and non-recurrence groups. We analyzed sex, age, amblyopia type, treatment duration, visual acuity, and binocular status.RESULTS: Of the 117 patients, 25 (21.4%) experienced recurrences. In that group, 60.0% of patients (compared to 14.1% of the no-recurrence group) exhibited high-frequency strabismus (p < 0.001). The recurrence group were younger than the no-recurrence group at both the beginning and end of treatment (p < 0.05). None of visual acuity at treatment commencement or end, stereoacuity, or suppression affected amblyopia recurrence.CONCLUSIONS: Recurrent amblyopia is frequent after initial successful treatment if the patient exhibits strabismus or is young.

A Comparison of Nagel Anomaloscope and Farnsworth Munsel 100-hue in Congenital Color Vision Deficiency

PURPOSE: To compare the classification and severity of congenital color vision deficiency using a Nagel anomaloscope and Farnsworth Munsel 100-hue Test (FM 100-hue).METHODS: A total of 394 eyes of 197 patients diagnosed with congenital color vision deficiency were included. Examinations using a Nagel anomaloscope and FM 100-hue were performed, and color vision abnormalities were classified as a protan color defect or deutan color defect by each test, and the degrees of color vision abnormalities were compared.RESULTS: The tests showed 64.3% (p < 0.001) agreement in the classification of color vision deficiencies. The Nagel anomaloscope was able to classify all cases, whereas 143 eyes (36.3%) could not be classified using the FM 100-hue test. In the case of the same type of color vision abnormality in both eyes, 196 cases (99.5%) using the Nagel anomaloscope and 111 cases (56.3%) using the FM 100-hue were observed. Regarding the degree of color defect, there was a moderate positive correlation between the two tests (r = 0.43; p < 0.001). There were no significant differences in the total error scores between mild anomalous trichromacy and severe anomalous trichromacy as assessed using FM 100-hue (p = 0.087).CONCLUSIONS: The Nagel anomaloscope was a more appropriate test for discerning the degree of color defect and binocular classification. In severity assessments, there was a moderate positive correlation between the two test methods. However, there were no significant differences in the total error scores between mild anomalous trichromacy and severe anomalous trichromacy as assessed using FM 100-hue. Therefore, it was difficult to perform severity classification using the Nagel anomaloscope based on the total error score of the FM 100-hue test.

Clinical Outcomes of Patients Implanted with Bifocal and Extended Depth of Focus Intraocular Lenses

PURPOSE: To compare the postoperative clinical outcomes after cataract surgery with implantation of bifocal intraocular lenses (IOLs) and extended depth of focus (EDOF) IOLs. METHODS: A total of 60 patients were divided into three groups, and each group included 20 patients of 40 eyes: group A with a +3.25 D bifocal IOL in both eyes, group B with an EDOF IOL in both eyes, and group C with a +3.25 D bifocal in one eye and an EDOF IOL in the other eye. We retrospectively reviewed the patients' medical charts to analyze their binocular uncorrected visual acuities (UCVAs; distant, intermediate, and near) and refraction at postoperative 3 months. RESULTS: The binocular distant UCVAs were 0.04 ± 0.01, 0.05 ± 0.02, and 0.04 ± 0.01 in groups A, B, and C, respectively, and there were no differences between the groups (p > 0.05). The intermediate UCVAs were 0.16 ± 0.01, 0.10 ± 0.01, and 0.10 ± 0.01, respectively, and group A was the lowest (A–B, p = 0.031; A–C, p = 0.018; B–C, p = 1.000). The near UCVAs were 0.05 ± 0.01, 0.24 ± 0.01, and 0.13 ± 0.01, respectively, and there were significant differences between the groups (A–B, p < 0.001, A–C: p = 0.009; B–C, p = 0.003). CONCLUSIONS: There were no significant differences among the three groups in binocular distant UCVA, and groups B and C showed better intermediate UCVAs than group A. Near UCVA was ranked in the order of groups A, C, B.

Interocular Symmetry of Optical Coherence Tomography Angiography Parameters in Normal Eyes of Korean Adults

PURPOSE: To evaluate the interocular symmetry of microvascular parameters measured by optical coherence tomography angiography (OCTA) in normal eyes of Korean adults. METHODS: We retrospectively reviewed the retinal microvascular structure of 91 healthy Korean subjects (182 eyes). We used OCTA to measure the area of the foveal avascular zone (FAZ), vessel density (VD), and perfusion density (PD) in both eyes. Intraclass correlation coefficients (ICCs), coefficients of variation (CVs), and Pearson correlation coefficients were calculated to evaluate the extent of agreement and correlations between binocular OCTA measurements. RESULTS: Both eyes had similar microvascular characteristics: FAZ area (right eye: 0.31 ± 0.11 mm², left eye: 0.30 ± 0.10 mm², p = 0.98), FAZ perimeter (right eye: 2.35 ± 0.45 mm, left eye: 2.36 ± 0.39 mm, p = 0.86). VD 1-mm center (right eye: 9.42 ± 2.75, left eye: 9.14 ± 2.96, p = 0.163), full area (right eye: 19.94 ± 1.65, left eye: 19.72 ± 1.76, p = 0.285), and PD 1-mm center (right eye: 0.16 ± 0.05, left eye: 0.16 ± 0.05, p = 0.151), full area (right eye: 0.36 ± 0.03, left eye: 0.36 ± 0.04, p = 0.716). All ICC values were above 0.8 and all CVs below 10%. CONCLUSIONS: The microvascular structure, as represented by the VD, PD, and FAZ area measured via OCTA, was bilaterally symmetric in normal eyes of Korean adults.

Papilledema with Cerebral Venous Sinus Thrombosis

PURPOSE: We report two patients diagnosed with a sinus thrombosis with papillary edema. CASE SUMMARY: Case 1 was a 27-year-old male who presented with complaints of headache and vomiting for 2 months and blurred vision in both eyes. The best-corrected visual acuity (BCVA) was 1.0 in the right eye and 1.0 in the left eye. A visual field (VF) examination revealed a binocular peripheral VF defect and optical coherence tomography (OCT) and a fundus examination indicated optic disc swelling in both eyes. Brain magnetic resonance imaging (MRI) showed no specific finding but magnetic resonance venography revealed filling defect signs in the transverse sinus and a cerebrospinal fluid examination indicated elevated intracranial pressure (ICP). Case 2 was a 54-year-old female who came to our hospital with suspicion of bilateral optic disc swelling. The BCVA was 0.9 in the right eye and 1.0 in the left eye. A VF examination revealed an inferior-temporal VF defect and blind spot enlargement in the right eye. OCT and a fundus examination showed optic disc swelling in both eyes. Brain MRI showed no specific finding but magnetic resonance venography revealed a decrease in blood flow in the transverse sinus, sigmoid sinus. A cerebrospinal fluid examination indicated elevated ICP. CONCLUSIONS: In the case of optic disc swelling in both eyes, a secondary cause of ICP elevation and the possibility of optic disc swelling due to sinus thrombosis should be considered, and brain MRI and venography are needed to distinguish these possibilities.

Presenting Internuclear Ophthalmoplegia with Peripheral Type Facial Palsy: Seven-and-a-Half Syndrome

A 49-year-old male presented with horizontal binocular diplopia without facial pain or skin lesion. Limitation of medial gaze in the left eye was revealed on neurological examination, which is accompanied by peripheral facial nerve palsy ipsilaterally. The diagnosis had been made based on the diffusion restriction lesion of left pontine tegmentum. We may denominate a “seven-and-a-half syndrome” and clinician should maintain a high level of awareness of the various syndromes associated with pontine lesions.

Objective Verification of Physiologic Changes during Accommodation under Binocular, Monocular, and Pinhole Conditions

BACKGROUND: To objectively investigate accommodative response to various refractive stimuli in subjects with normal accommodation. METHODS: This prospective, non-randomized clinical trial included 64 eyes of 32 subjects with a mean spherical equivalent −1.4 diopters (D). We evaluated changes in accommodative power, pupil diameter, astigmatic value, and axis when visual stimuli were applied to binocular, monocular (dominant eye, non-dominant eye, ipsilateral, and contralateral), and pinhole conditions. Visual stimuli were given at 0.25 D (4 m), 2 D (50 cm), 3 D (33 cm), and 4 D (25 cm) and accommodative response was evaluated using open view binocular autorefractor/keratometer. RESULTS: The accommodative response to binocular stimulus was 90.9% of the actual refractive stimulus, while that of the monocular stimulus was 84.6%. The binocular stimulus induced a smaller pupil diameter than did the monocular stimulus. There was no difference in accommodative response between the dominant eye and non-dominant eye or between ipsilateral and contralateral stimuli. As the refractive stimuli became stronger, the absolute astigmatic value increased and the direction of the astigmatism axis became more horizontal. Pinhole glasses required 10%–15% less accommodative power compared with the monocular condition. CONCLUSION: Binocular stimuli enable more precise and effective accommodation than do monocular stimuli. Accommodative response is composed of 90% true accommodation and 10% pseudo-accommodation, and the refractive stimulus in one eye affects the contralateral eye to the same extent. This should be taken into account when developing guidelines for wearing smart glasses while driving, as visual stimulation is applied to only one eye, but far distance attention is constantly needed. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03557346

Association between Glycated Hemoglobin A1c and Intraocular Pressure in Nondiabetic Subjects

BACKGROUND: Diabetic patients are known to have unusually high mean intraocular pressure (IOP); attributable to autonomic dysfunction and genetic factors. A recent study reported that diabetic complications occur in not only diabetes but also prediabetes. We performed this study to analyze the relationship between glycated hemoglobin A1c (HbA1c) levels and IOP in non-diabetics using electronic medical records at the health screening center of Soon Chun Hyang University Seoul Hospital.METHODS: We considered 16,643 individuals who visited the health screening center of Soon Chun Hyang University Seoul Hospital between November 2015 and September 2017. In total, 3,029 subjects were included in the study. Exclusion criteria included a history of hypertension, diabetes, stroke, cardiovascular disease, hepatitis (A-C), cancer, other disease, fasting blood glucose of 126 mg/dL or higher, HbA1c of 6.5% or higher, and individuals whose binocular IOP could not be measured. We categorized subjects into two groups; those with HbA1c less than or equal to 5.6%, and those with HbA1c greater than 5.6% and less than 6.5%. The mean IOP of each group was compared by gender.RESULTS: After adjusting for factors affecting IOP, analysis of variance was performed to analyze the relationship between HbA1c and IOP. There was no statistically significant difference between the HbA1c groups in males. However, there was a significant difference in IOP between females in the the higher and lower HbA1c groups.CONCLUSION: There was a statistically significant relationship between mean IOP and HbA1c in females without diabetes. Further research is needed with prospective and extensive data collection.

Ayudas ópticas y no ópticas en la baja visión / Visual and not visual aid in low vision

Este estudio se propone conocer la ayuda visual mejor aceptada por pacientes de visión baja, para lo cual se realizó una revisión bibliográfica con el fin de contribuir al ejercicio optométrico. Se revisaron un total de 28 artículos del año 2007 a la fecha actual. En las diferentes patologías en estudio se encontró que la ayuda visual mejor aceptada para la visión cercana fueron las lupas, y para la visión lejana eran más usados los telescopios(AU)

The aim of this study is to determine which is the most frequent visual aid use in low vision. Twenty-eight articles were consulted in a period from 2007 until now. It was observed that for near vision the hans spectacles were the best aid and for far vision telescope were more used(AU)

Assessment of visual acuity improvement in patients with AMD referred to the low vision department / Avaliação da melhora da acuidade visual em pacientes com DMRI encaminhados ao setor de visão subnormal

Abstract Purpose: To evaluate the vision improvement through the use of visual aids of patients with Age-Related Macular Degeneration (AMD) those were examined in the low vision department. Methods: A retrospective study was conducted by reviewing medical records of 61 patients with AMD who were referred to the Low Vision Department from January 2012 to December 2014. The data collected included age, sex, diagnosis of the type of AMD and previous use of vascular endothelium growth factor inhibitor or antioxidants. In addition, far acuity, with and without optical aid, was indicated as well as which aid was prescribed. Results: In this study with 61 patients, 54.1% were male and 45.9% female. The most prevalent age group was 71-80 years old (44.3%) and most of the patients had the dry form of AMD (70.5%). With the use of visual aids, 73.8% of the patients improved visual acuity for far vision. The most prescribed optical aid was the Galileu 2.8x telescope (50.8%). Conclusion: Patients with visual impairment and AMD can benefit significantly from the visual aids if they are properly prescribed and fitted. Most patients in the study were fitted with at least one of the indicated visual aids, resulting in a significant improvement in far acuity.

Resumo Objetivo: Avaliar a melhora da visão através de auxílios visuais em pacientes portadores de Degeneração Macular Relacionada a Idade (DMRI) encaminhados ao serviço de visão subnormal. Métodos: Foi realizado um estudo retrospectivo, através da revisão 61 prontuários de pacientes com diagnóstico de DMRI que foram encaminhados ao departamento de Visão Subnormal (VSN), no período de janeiro 2012 a dezembro de 2014. Foram coletados dados sobre idade, sexo, diagnóstico do tipo de DMRI e uso prévio de inibidor do fator de crescimento do endotélio vascular (anti-VEGF) ou antioxidante. Além disso, outras informações foram colhidas como acuidade visual para longe sem auxílio e com auxílio óptico, indicando o(s) auxílio(s) óptico(s) prescrito(s). Resultados: Dos 61 pacientes avaliados, 54,1% eram do sexo masculino e 45,9% do sexo feminino. A faixa etária mais prevalente foi de 71-80 anos (44,3%) e a maioria (70,5%) apresentava a forma seca de DMRI. Com o uso de recursos visuais, 73,8% dos tiveram melhora da acuidade visual para longe. O auxilio óptico mais prescrito foi o telescópio do tipo Galileu 2,8x (50,8%). Conclusão: Pacientes com deficiência visual e DMRI podem se beneficiar significativamente dos recursos visuais se esses forem devidamente indicados e adaptados. A maioria dos pacientes aceitou pelo menos um dos recursos visuais indicados resultando numa melhora importante da acuidade visual de longe.

Comparison of Binocular Function and Surgical Outcomes of Tenacious Proximal Fusion and High Accommodative Convergence/Accommodation Ratio Types of Intermittent Exotropia

PURPOSE: To compare the characteristics and surgical outcomes in patients with tenacious proximal fusion (TPF) and high accommodative convergence/accommodation ratio (AC/A) types of intermittent exotropia. METHODS: This study retrospectively enrolled 40 patients with intermittent exotropia, 23 with TPF and 17 with high AC/A. Binocular function was evaluated by Worth's 4-dot test. Patients underwent lateral rectus recession, and surgical outcomes were compared. Surgical success was defined as less than ±10 prism diopters (PD) at 12 months postoperatively. RESULTS: The proportion of diplopia at near, evaluated by Worth's 4-dot test, was significantly higher in patients with high AC/A than in those with TPF (35.3% vs. 4.3%, p = 0.029). The mean preoperative angles of deviation in TPF and high AC/A types were 28.3 ± 4.4 and 28.8 ± 4.5 PD at distances, and 14.7 ± 4.2 and 15.1 ± 4.1 PD at near. Twelve months after surgery, the mean angles of deviation in TPF and high AC/A types were 2.9 ± 9.8 and 1.2 ± 9.6 PD, respectively, at distance and 1.7 ± 7.7 and −1.3 ± 11.3 PD at near. The surgical success rates were similar in the TPF and high AC/A types (74.0% vs. 64.7%). Five (21.7%) patients with TPF and 2 (11.8%) with high AC/A type experienced recurrence, with consecutive esotropia occurring in 1 (4.3%) patient with TPF and 4 (23.5%) patients with high AC/A. CONCLUSIONS: The proportion of diplopia at near was higher in patients with high AC/A type than in those with TPF intermittent exotropia. However, the surgical success rates were not significantly different between the types.

Trifocal versus Bifocal Diffractive Intraocular Lens Implantation after Cataract Surgery or Refractive Lens Exchange: a Meta-analysis

BACKGROUND: We compared the efficacy between trifocal and bifocal diffractive intraocular lens (IOL) implantation. METHODS: Through PubMed, MEDLINE, EMBASE, and CENTRAL, we searched potentially relevant articles published from 1990 to 2018. Defocus curves, visual acuities (VAs) were measured as primary outcomes. Spectacle dependence, postoperative refraction, contrast sensitivity (CS), glare, and higher-order aberrations (HOAs) were measured as secondary outcomes. Effects were pooled using random-effects method. RESULTS: We included 11 clinical trials, with a total of 787 eyes (395 subjects). The trifocal IOL group showed better binocular distance VA corrected with defocus levels of −0.5, −1.0, −1.5, and −2.5 diopter than the bifocal IOL group (All P ≤ 0.004). The trifocal IOL group showed better monocular uncorrected distance and intermediate VAs (mean difference [MD], −0.04 logarithm of the minimum angle of resolution [logMAR]; 95% confidence interval [CI], −0.07, −0.01; P = 0.006 and MD, −0.07 logMAR; 95% CI, −0.13, −0.01; P = 0.03, respectively). Postoperative refraction, glare, CS, and HOAs were not significantly different from each other. CONCLUSION: The overall findings indicate that trifocal diffractive IOL implantation is better than the bifocal diffractive IOL in intermediate VA, and provides similar or better in distance and near VAs without any major deterioration in the visual quality.

Subnormal Binocular Contrast Sensitivity Summation in Patients with Intermittent Exotropia

BACKGROUND: To evaluate binocular summation ratio using contrast sensitivity (CS) testing and correlation between binocular summation and stereoacuity, and control scale in intermittent exotropia (IXT). METHODS: We conducted a prospective case-control study. Thirty-seven IXT and 41 controls were evaluated with both monocular and binocular CS testing. We compared the binocular summation ratio of IXT to that of controls. Near and distance stereoacuity was assessed and office-based control scale was evaluated. We investigated correlation between binocular CS summation ratio and stereoacuity, and control scale in IXT, respectively. RESULTS: IXT had lower binocular CS summation ratio than controls at 1.5 and 3.0 cycles/degree (1.01 ± 1.02 vs. 1.62 ± 1.88 and 1.17 ± 0.96 vs. 1.86 ± 1.75, Both P < 0.05). We found significant correlation between binocular CS summation ratio at 3.0 cycles/degree and both near and distance stereoacuity (r = −0.411, P = 0.012 and r = −0.624, P = 0.005), and ratio at 1.5 cycles/degree also correlated significantly with distance stereoacuity (r = −0.397, P = 0.034) in the IXT. Binocular CS summation ratio was correlated to control scale at 1.5 and 3.0 cycles/degree (r = −0.327, P = 0.041 and r = −0.418, P = 0.028), and the ratio significantly differed in control scale groupings analysis at the same frequencies (Both P < 0.05). CONCLUSION: Our findings of subnormal binocular CS summation ratio in IXT had correlation with stereoacuity and control scale suggest that binocular CS testing may be a useful method in assessing binocular visual function in IXT.

Therapeutic Outcomes of Prism Glasses for Diplopia Unrelated to Strabismus Surgery

PURPOSE: To evaluate the therapeutic results of the patients wearing the prism glasses due to strabismus with diplopia unrelated to strabismus surgery. METHODS: Between May 2002 and October 2016, this retrospective study evaluated medical records of 23 patients who were wearing prism glasses due to strabismus with diplopia unrelated to strabismus surgery. The patients failed to adjust to the prism glasses and stopped within 3 months were defined as the adaptation failure group. The patients wearing prism glasses for 3 months or more was defined as adaptation success group. In the prism adaptation success group, he patients who underwent strabismus surgery during follow up were defined as treatment failure. Data were collected the types and causes of strabismus, the deviation angle at starting treatment of prism glasses and last visits, best corrected visual acuity, Titmus stereo test and Worth 4 dot test. RESULTS: Of the total 23 patients, 18 patients had horizontal strabismus, four patients had vertical strabismus and one had horizontal and vertical strabismus. The causes of strabismus were acute acquired comitant esotropia (12 patients), paralytic strabismus (9 patients), and thyroid associated ophthalmopathy (two patients). There was no significant changes in deviation angle as well as the prism diopter of prism glasses after prism glasses treatmet. The prism glasses-adaptation group was 70%, and 31% of them were performed strabismus surgery. There was no reduction in visual acuity in all patients. Among the prism glasses adaptation group, 33% of the prism glasses-adaptation group had poor binocular function. CONCLUSIONS: In the strabismus patients with diplopia unrelated to strabismus surgery 70% of the patients adapted prism glasses more than 3 months and 31% of them required strabismus surgery. Therefore, prism glasses treatment may be one of the non-surgical approaches in the strabismus patients with diplopia unrelated to strabismus surgery.

Risk Factors of Secondary Glaucoma after Congenital Cataract Surgery in Korean Patients

PURPOSE: To assess the risk of development of secondary glaucoma after congenital cataract surgery using a long-term follow-up study. METHODS: In total, 148 eyes of 91 patients who underwent congenital cataract surgery at our hospital or other hospitals were included in a retrospective chart review. A diagnosis of secondary glaucoma was made if the intraocular pressure (IOP) exceeded 21 mmHg and the corneal diameter, axial length, or the cup-to-disc ratio increased, or surgery was performed to control the IOP. To analyze the clinical features and risk factors of secondary glaucoma, we evaluated the mean age at cataract surgery, binocularity, presence of a nuclear cataract, methods of cataract surgery, presence of an intraocular lens (IOL), duration of diagnosis of secondary glaucoma after cataract surgery, duration of follow-up, recent best-corrected visual acuity, and refractive errors. RESULTS: Thirty-five eyes (23.6%) were diagnosed with secondary glaucoma as a complication of congenital cataract surgery. Of these, 11 eyes (31.4%) were treated with glaucoma surgery a mean of 3.4 times. The mean duration from congenital cataract surgery to diagnosis of glaucoma was 112.2 ± 113.1 months. Patients with aphakia had a higher risk of developing secondary glaucoma compared with patients undergoing primary IOL implantation (p = 0.001). Younger age (<3 months at surgery), a nuclear cataract, and aphakia were risk factors for the development of secondary glaucoma (p = 0.03, p = 0.006, and p < 0.001, respectively), and the risk of developing secondary glaucoma increased with secondary IOL implantation (p = 0.052). CONCLUSIONS: Secondary glaucoma after congenital cataract surgery was more common in patients with secondary IOL implantation, aphakia, a younger age (<3 months), and a nuclear cataract. Patients who underwent congenital cataract surgery had an increased risk for developing secondary glaucoma. Long-term monitoring of the IOP and optic nerve is therefore required for these patients.

Stereopsis before and after Inferior Oblique Weakening Surgery

PURPOSE: To analyze stereopsis change before and after inferior oblique weakening surgery. METHODS: We retrospectively reviewed the medical records of 31 patients who had undergone inferior oblique weakening surgery. The factors analyzed included sex, age at surgery, preoperative and postoperative visual acuity (VA), time from first detection to surgery, degree of inferior oblique overaction (IOOA), primary/secondary IOOA, exotropia/hypertropia, bilaterality, and type of surgery. RESULTS: Eighteen patients with a mean age 7.3 ± 3.1 years exhibited stereopsis of 60 arc seconds or better before surgery and 17 had stereopsis better than 60 arc seconds after surgery. Postoperatively, stereopsis improved in 13 patients and deteriorated in 9. Better preoperative VA and the absence of superior oblique underaction were associated with better preoperative stereopsis. Better preoperative VA, postoperative VA, and the presence of head tilt were associated with better postoperative stereopsis. Unilateral inferior oblique weakening surgery and accompanying hypertropia were associated with improved stereopsis, while the absence of hypertropia was associated with deteriorated stereopsis. CONCLUSIONS: In this retrospective study, 58.1% of patients tended to have bifoveal fixation. When a vertical deviation is present in the primary position due to unilateral IOOA, IO weakening surgery can be expected to improve binocular function.

Two Cases of Corneal Neovascularization Improved by Electrocauterization and Subconjunctival Bevacizumab Injection

PURPOSE: To report an experience of improving symptoms through treatment with electrocauterization and subconjunctival bevacizumab injection in two patients with keratitis accompanied by corneal neovascularization and opacity. CASE SUMMARY: (Case 1) A 20-year-old woman visited our institution complaining of binocular blurred vision and congestion for the previous 3 years. Her best corrected visual acuity (BCVA) was 0.07 in the right eye and 0.4 in the left eye (Han Chun-suk visual acuity chart, decimal). The diagnosis was bilateral rosacea keratitis. Antibiotics, steroid eye drops and oral antibiotics were administered, but no improvement was observed. Electrocauterization was performed at the origin of the neovascularization of the cornea and bevacizumab was injected at the peripheral subconjunctiva in the right eye. Thereafter the corneal neovascularization did not recur, corneal opacity was reduced, and BCVA improved to 0.5. (Case 2) A 19-year-old woman visited complaining of left eye congestion for the previous 3 years. Her BCVA was 1.0 in the right eye and 0.08 in the left eye.The diagnosis was phlyctenular keratitis of the left eye. Antibiotics, steroid eye drops and oral antibiotics were administered, but no improvement was observed. Therefore, electrocauterization and subconjunctival bevacizumab injection were performed in the cornea of the left eye, after which corneal neovascularization and opacity decreased. CONCLUSIONS: In these cases, we report improvement of symptoms after treatment with electrocauterization and subconjunctival bevacizumab injection after failed treatment of palpebral sanitation, antibiotic and steroid.

Pediatric visual acuity examinations and vision care

The visual system of newborn infants is not like that of adults. Both ocular and neural structures essential for vision will undergo anatomical and physiological changes as maturation process. The maturation of all visual systems occurs relatively rapidly in normal children. So, early examination of visual acuity is critical for normal visual funciton achievement. Visual acuity in preverbal children can be assessed using several techniques, such as fixation and following behavior under both monocular and binocular conditions, the optokinetic nystagmus technique, preferential looking, visual evoked potential, and recognition acuity using a vision chart. Most clinicians consider the standard technique of recognition acuity to be the gold standard for visual acuity assessments, 20/20 vision should be achieved by 7 years of age. Significant refractive error, a high degree of hyperopia, myopia, or astigmatism may result in not only blurred vision, but also strabismus and amblyopia. Therefore, early vision screening is very valuable. Subjective and objective refractive techniques are standard for detecting significant refractive errors in children and are available under either non-cycloplegic or cycloplegic conditions. Amblyopia is the most common cause of vision loss in children and young adults, defining as a reduction of best-corrected visual acuity due to the interruption of normal visual development during the so-called sensitive period. If the problem is not identified until the sensitive period is complete, the vision loss is permanent. Visual impairment in childhood affects all aspects of the child's development. Earlier treatment is associated with better outcomes. Of course, patient compliance and parental support are the most important factors contributing to treatment success.

Pediatric visual acuity examinations and vision care

The visual system of newborn infants is not like that of adults. Both ocular and neural structures essential for vision will undergo anatomical and physiological changes as maturation process. The maturation of all visual systems occurs relatively rapidly in normal children. So, early examination of visual acuity is critical for normal visual funciton achievement. Visual acuity in preverbal children can be assessed using several techniques, such as fixation and following behavior under both monocular and binocular conditions, the optokinetic nystagmus technique, preferential looking, visual evoked potential, and recognition acuity using a vision chart. Most clinicians consider the standard technique of recognition acuity to be the gold standard for visual acuity assessments, 20/20 vision should be achieved by 7 years of age. Significant refractive error, a high degree of hyperopia, myopia, or astigmatism may result in not only blurred vision, but also strabismus and amblyopia. Therefore, early vision screening is very valuable. Subjective and objective refractive techniques are standard for detecting significant refractive errors in children and are available under either non-cycloplegic or cycloplegic conditions. Amblyopia is the most common cause of vision loss in children and young adults, defining as a reduction of best-corrected visual acuity due to the interruption of normal visual development during the so-called sensitive period. If the problem is not identified until the sensitive period is complete, the vision loss is permanent. Visual impairment in childhood affects all aspects of the child's development. Earlier treatment is associated with better outcomes. Of course, patient compliance and parental support are the most important factors contributing to treatment success.