OBJECTIVE

Despite being a preventable and treatable condition, central microbial keratitis (CMK) and its complications remain to be a significant cause of vision loss in our country. This study presents the demographic profile, risk factors, etiologies, treatments, and outcomes of CMK in the Philippines.

The study was a two-center, prospective, non-randomized clinical study involving the patients of the External Disease and Cornea Clinics of two tertiary eye referral centers in the Philippines. It was conducted as the Philippine leg of the Asia Cornea Society Infectious Keratitis Study (ASCIKS).1 Patients with a clinical diagnosis of CMK rendered by a cornea specialist, and who signed the consent form, were recruited into the study. They underwent uniform sample collection and culture techniques as described in the ACSIKS. All patients were followed-up for 6 months. Data collected included demographics, risk factors, culture results, management, and treatment outcomes. Descriptive statistics and frequency were used to analyze the data.

A total of 348 patients diagnosed with CMK were included. Trauma (65.5%) among the middle-aged (42.9 ± 17.9 years) male population was the most significant risk factor for development of CMK, followed by contact lens wear (12.9%), prior ocular surgery (6.0%), and ocular surface diseases (3.4%). Bacterial keratitis (53.2%) was still the most common etiology of CMK, followed by fungal keratitis (27.0%), Acanthamoeba keratitis (5.7%), and viral keratitis (2.0%). Aspergillus species (18.3%) were the most common microbial isolates. Pseudomonas species (13.9%) were the most common bacterial isolates. The median time from onset of symptoms to consultation with the study centers was 2 weeks. Medical treatment was enough to treat the infection in 34.8% of cases. Surgical intervention was necessitated in 22.6% with evisceration/enucleation done in 1 out of 3 patients who had surgery.

Bacterial infection remains the most common cause of CMK in the Philippines, followed by fungal infection. Significant risk factors include trauma and contact lens wear. Aspergillus species and Pseudomonas species were the most common fungal and bacterial isolates, respectively. Despite medical treatment, almost a quarter of the cases still required surgical intervention.

INTRODUCTION: Visual impairment and obesity remain the major public health issues among school-age students in rural areas of China. Obesity is an underlying risk of vision problems. This study aimed to assess the association between visual impairment and body mass index (BMI) among school-age students in rural northwest China. METHODS: This study included 39,385 students from the 4 th to 9 th grade in rural northwest China. From 2018 to 2020, students underwent an assessment of visual acuity (VA) and completed a questionnaire on family demographics, and height and weight measurements. Multiple logistic regression analyses were used to analyse the data. RESULTS: The association between visual impairment and BMI groups was significant in the study population ( P = 0.002) and in different groups (at the different educational, provincial and national levels) ( P < 0.001, separately). Multiple logistic regression analyses revealed a positive relationship between visual impairment and obesity in the study population, including those attending primary school, Han students and the residents of Ningxia autonomous region. CONCLUSION The association between visual impairment and obesity was significant among school-age students in rural northwest China. There should be implementation of policies to address the problem about visual impairment and obesity among school-age students in rural areas.
Humans ; China/epidemiology* ; Body Mass Index ; Male ; Female ; Rural Population ; Vision Disorders/complications* ; Child ; Adolescent ; Students ; Surveys and Questionnaires ; Logistic Models ; Obesity/complications* ; Visual Acuity ; Cross-Sectional Studies

BACKGROUND: Visual input significantly influences cerebral activity related to locomotor navigation, although the underlying mechanism remains unclear. This study aimed to analyze the effects of chronic visual impairment and its rehabilitation on sensorimotor integration during level walking in patients with age-related cataract. METHODS: This prospective case series enrolled 14 female patients (68.4 ± 4.7 years) with age-related cataract, scheduled for consecutive cataract surgeries at the Department of Ophthalmology in Peking University Third Hospital from June 2019 to June 2020. Electroencephalogram (EEG) signals during level walking were recorded using a portable EEG system before and 4 weeks after visual restoration. Walking speed was assessed using the Footscan system. Spectral power of the theta and alpha bands was analyzed with repeated-measures analysis of variance, with Assignment (rest and walking), Phase (preoperative and postoperative), and Electrode sites (F3, Fz, F4, O1, and O2) as within-subject factors. RESULTS: Compared to the visual impairment state, theta band power significantly decreased after visual restoration (13.16 ± 1.58 μV 2vs. 23.65 ± 3.48 μV 2 , P = 0.018). Theta activity was notably reduced during walking (17.24 ± 2.43 μV 2vs. 37.86 ± 6.62 μV 2 , P = 0.017), while theta power at rest was not significantly different between the two phases (9.44 ± 1.24 μV 2vs. 9.08 ± 1.74 μV 2 , P = 0.864). Changes in walking speed were correlated with alterations in theta power at electrode sites of O1 ( r = -0.574, P = 0.032) and O2 ( r = -0.648, P = 0.012). Alpha band power remained stable during walking and was unaffected by visual status. CONCLUSIONS Chronic visual impairment from age-related cataract triggers enhanced cerebral activation of sensorimotor integration to compensate for visual decline during locomotion. This cerebral over-activation is effectively alleviated by visual restoration.
Humans ; Female ; Walking/physiology* ; Aged ; Electroencephalography/methods* ; Prospective Studies ; Middle Aged ; Cataract/physiopathology* ; Vision Disorders/physiopathology*

OBJECTIVES: Near vision loss (NVL) is one of the leading causes of visual impairment worldwide, exerting a profound impact on individual quality of life and socio-economic development. This study aims to analyze the burden of NVL in China by sex and age groups from 1990 to 2021 and to project trends over the next 15 years. METHODS: Using data from the Global Burden of Disease (GBD) 2021 database, we conducted descriptive analyses of NVL prevalence in China, calculated age-standardized prevalence rates (ASPR) and age-standardized disability-adjusted life years rates (ASDR) to compare burden differences between sexes and age groups, and applied an autoregressive integrated moving average (ARIMA) model to predict NVL trends for the next 15 years. The model selection was based on best-fit criteria to ensure reliable projections. RESULTS: From 1990 to 2021, China's ASPR of NVL rose from 10 096.24/100 000 to 15 624.54/100 000, and ASDR increased from 101.75/100 000 to 158.75/100 000. In 2021, ASPR (16 551.70/100 000) and ASDR (167.69/100 000) were higher among females than males (14 686.21/100 000 and 149.76/100 000, respectively). China ranked highest globally in both NVL cases and disability-adjusted life years (DALYs), with female burden significantly exceeding male burden. Projections indicated this trend and sex gap will persist until 2036. Compared with 1990, the prevalence cases and DALYs increased by 239.20% and 238.82%, respectively in 2021, with the highest burden among females and the 55-59 age group. The ARIMA model predicted continued increases in prevalence and DALYs by 2036, with females maintaining a higher burden than males. CONCLUSIONS This study reveals a marked increase in the NVL burden in China and predicts continued growth in the coming years. Public health policies should prioritize NVL prevention and control, with special attention to women and middle-aged populations to mitigate long-term societal and health impacts.
Humans ; China/epidemiology* ; Male ; Female ; Prevalence ; Middle Aged ; Disability-Adjusted Life Years ; Adult ; Global Burden of Disease ; Adolescent ; Quality-Adjusted Life Years ; Aged ; Sex Factors ; Child ; Young Adult ; Child, Preschool ; Cost of Illness ; Infant ; Aged, 80 and over ; Vision Disorders/epidemiology*

OBJECTIVE

To compare the frequency and severity of color vision defects between diabetes mellitus (DM) patients without retinopathy and those with mild non-proliferative diabetic retinopathy (NPDR), and to evaluate the relationship between these color vision defects and capillary blood glucose (CBG) levels.

This was a cross-sectional, hospital-based study conducted over a seven-month period at the Ophthalmology Outpatient Department of Cardinal Santos Medical Center. Thirty-five (35) DM patients (70 eyes) aged 50 to 75 years with best-corrected visual acuity of ≥20/50 and no more than mild NPDR were included. Patients with moderate or severe NPDR, macular edema, optic nerve pathology, or significant cataracts were excluded. All participants underwent visual acuity testing, fundus examination, and color vision assessment using the Ishihara pseudoisochromatic plates and Farnsworth D-15 tests conducted under standardized lighting conditions. CBG was measured using the finger-prick method. Main outcome measures included the proportion and type of color vision defects, their association with DR classification, and CBG levels. Statistical analyses included descriptive statistics, the Fisher exact test, the Mann-Whitney U test for the Farnsworth D-15 Color Confusion Index (CCI), and Spearman correlation between CBG and CCI.

Tritan-type defects were the most common, accounting for 36.2%. Color vision defects were observed in 91.3% (64 eyes) of patients with no DR, while defects were seen in all eyes (100%) with mild NPDR (5 eyes). However, this difference was not statistically significant (p = 1.000). There was no significant correlation between CBG levels and color vision scores. Mean CCI scores were similar between groups (p = 0.394), indicating no substantial difference in defect severity.

Color vision defects may be more prevalent in early NPDR compared to no DR, but this difference was not significant in this sample. No correlation was found between CBG levels and color vision performance. Color vision testing may serve as a useful adjunctive screening tool for early diabetic retinal changes; however, further studies with larger sample sizes are necessary.

Three different preclinical evaluation methods of MTF through-frequency response, MTF through-focus-response and expected visual acuity were used to compare and analyze the imaging differences of IOLs with four different optical designs. The research work could be used in the simultaneous vision IOLs in the optical design stage and verify the optical quality of the IOLs, the results can predict the visual representation of the patients better. The evaluation results can provide reference for IOL manufacturers and users in product design, development, validation and application selection.
Humans ; Prosthesis Design ; Lenses, Intraocular ; Vision, Ocular ; Visual Acuity

Adult ; Humans ; Middle Aged ; Theory of Planned Behavior ; Vision Screening

Objective: To analyze the clinical characteristics of patients with Mucopolysaccharidosis ⅣA (MPS ⅣA). Methods: A retrospective study was conducted on 111 patients with MPS ⅣA in Xinhua Hospital of Shanghai Jiao Tong University School of Medcine from December 2008 to August 2020, confirmed by enzyme activity and genetic testing. General situation, clinical manifestations and enzyme activity test results were analyzed. According to the clinical manifestations, it can be divided into severe, intermediate and mild group. The independent sample t test was used to compare the birth body length and weight of children with that of normal boys and girls, and group comparisons of enzyme activities were evaluated by median test. Results: One hundred and eleven unrelated patients, 69 males and 42 females, were classified into 3 subtypes: severe (n=85), intermediate (n=14), and mild (n=12). The age at symptom onset were 1.6 (1.0, 3.0) years, and at diagnosis were 4.3 (2.8, 7.8) years. Skeletal manifestations were observed in all patients and consisted mainly of pectus carinatum (96/111, 86.5%), motor dysfunction (78/111, 70.3%), spinal deformity (71/111, 64.0%), growth retardation (64/111, 57.7%), joint laxity (63/111, 56.8%) and genu valgum (62/111, 55.9%). Eighty-eight patients (88/111, 79.3%) with MPS ⅣA were also along with non-skeletal manifestations, mainly including snoring (38/111, 34.2%), coarse faces (34/111, 30.6%), and visual impairment (26/111, 23.4%). The most common skeletal manifestation was pectus carinatum (79 cases), and non-skeletal manifestation was snoring (30 cases) and coarse faces (30 cases) in severe patients, pectus carinatum (13 cases) and snoring (5 cases) in intermediate type, motor dysfunction (11 cases) and snoring (3 cases) and visual impairment (3 cases) in mild patients. The height and weight of severe patients began to fall below -2 s at 2-<5 years and 5-<7 years, respectively. At the age of 10-<15 years, the standard deviation score of the height of severe patients reached (-6.2±1.6) s in males and (-6.4±1.2) s in females, and the score of weight got (-3.0±1.1) s in males and (-3.5±0.5) s in females. The height of intermediate patients began to fall below -2 s at the age of 7-<10 years, and the standard deviation score of height were -4.6 s and -3.6 s in 2 males, and -4.6 s and -3.8 s in 2 females at the age of 10-<15 years. The weight remained within -2 s in 72.0% (18/25) of intermediate patients compared to age-matched healthy children. In the mild patients with MPS ⅣA, the mean standard deviation score of height and weight was within -2 s. The enzyme activities of mild patients (2.02 (1.05, 8.20) nmol/(17 h·mg)) were both significantly higher than that of intermediate (0.57 (0.47, 0.94) nmol/(17 h·mg)) and severe (0.22 (0, 0.59) nmol/(17 h·mg)) patients (Z=9.91, 13.98, P=0.005, 0.001), and the enzyme activity of intermediate patients was significantly higher than that of severe patients (Z=8.56, P=0.010). Conclusions: The clinical manifestations of MPS ⅣA are charactered by pectus carinatum, motor function impairment, spinal deformity and growth retardation. The clinical characteristics, growth rate and enzyme activity differ among the 3 subtypes of MPS ⅣA.
Male ; Child ; Female ; Humans ; Adolescent ; Mucopolysaccharidosis IV ; Pectus Carinatum ; Retrospective Studies ; Snoring ; China ; Mucopolysaccharidoses ; Growth Disorders ; Vision Disorders

OBJECTIVES: To investigate the characteristics and objective assessment method of visual field defects caused by optic chiasm and its posterior visual pathway injury. METHODS: Typical cases of visual field defects caused by injuries to the optic chiasm, optic tracts, optic radiations, and visual cortex were selected. Visual field examinations, visual evoked potential (VEP) and multifocal visual evolved potential (mfVEP) measurements, craniocerebral CT/MRI, and retinal optical coherence tomography (OCT) were performed, respectively, and the aforementioned visual electrophysiological and neuroimaging indicators were analyzed comprehensively. RESULTS: The electrophysiological manifestations of visual field defects caused by optic chiasm injuries were bitemporal hemianopsia mfVEP abnormalities. The visual field defects caused by optic tract, optic radiation, and visual cortex injuries were all manifested homonymous hemianopsia mfVEP abnormalities contralateral to the lesion. Mild relative afferent pupil disorder (RAPD) and characteristic optic nerve atrophy were observed in hemianopsia patients with optic tract injuries, but not in patients with optic radiation or visual cortex injuries. Neuroimaging could provide morphological evidence of damages to the optic chiasm and its posterior visual pathway. CONCLUSIONS Visual field defects caused by optic chiasm, optic tract, optic radiation, and visual cortex injuries have their respective characteristics. The combined application of mfVEP and static visual field measurements, in combination with neuroimaging, can maximize the assessment of the location and degree of visual pathway damage, providing an effective scheme for the identification of such injuries.
Humans ; Optic Chiasm/pathology* ; Visual Pathways/pathology* ; Visual Fields ; Evoked Potentials, Visual ; Random Amplified Polymorphic DNA Technique ; Hemianopsia/complications* ; Vision Disorders/pathology* ; Optic Nerve Injuries/diagnostic imaging* ; Brain Injuries, Traumatic/diagnostic imaging*

OBJECTIVES: To study the virtual reality-pattern visual evoked potential (VR-PVEP) P100 waveform characteristics of monocular visual impairment with different impaired degrees under simultaneous binocular perception and monocular stimulations. METHODS: A total of 55 young volunteers with normal vision (using decimal recording method, far vision ≥0.8 and near vision ≥0.5) were selected to simulate three groups of monocular refractive visual impairment by interpolation method. The sum of near and far vision ≤0.2 was Group A, the severe visual impairment group; the sum of near and far vision <0.8 was Group B, the moderate visual impairment group; and the sum of near and far vision ≥0.8 was Group C, the mild visual impairment group. The volunteers' binocular normal visions were set as the control group. The VR-PVEP P100 peak times measured by simultaneous binocular perception and monocular stimulation were compared at four spatial frequencies 16×16, 24×24, 32×32 and 64×64. RESULTS: In Group A, the differences between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at 24×24, 32×32 and 64×64 spatial frequencies were statistically significant (P<0.05); and the P100 peak time of normal vision eyes at 64×64 spatial frequency was significantly different from the simulant visual impairment eyes (P<0.05). In Group B, the differences between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at 16×16, 24×24 and 64×64 spatial frequencies were statistically significant (P<0.05); and the P100 peak time of normal vision eyes at 64×64 spatial frequency was significantly different from the simulant visual impairment eyes (P<0.05). In Group C, there was no significant difference between P100 peak times of simulant visual impairment eyes and simultaneous binocular perception at all spatial frequencies (P>0.05). There was no significant difference in the P100 peak times measured at all spatial frequencies between simulant visual impairment eyes and simultaneous binocular perception in the control group (P>0.05). CONCLUSIONS VR-PVEP can be used for visual acuity evaluation of patients with severe and moderate monocular visual impairment, which can reflect the visual impairment degree caused by ametropia. VR-PVEP has application value in the objective evaluation of visual function and forensic clinical identification.
Humans ; Evoked Potentials, Visual ; Vision, Ocular ; Vision, Binocular/physiology* ; Vision Disorders/diagnosis* ; Virtual Reality