Lamina Cribrosa Microstructure in Nonhuman Primates With Naturally Occurring Peripapillary Retinal Nerve Fiber Layer Thinning.

Purpose: The lamina cribrosa (LC) is hypothesized to be the site of initial axonal damage in glaucoma with the circumpapillary retinal nerve fiber layer thickness (RNFL-T) widely used as a standard metric for quantifying the glaucomatous damage. The purpose of this study was to determine in vivo, 3-dimensional (3D) differences in the microstructure of the LC in eyes of nonhuman primates (NHPs) with naturally occurring glaucoma. Methods: Spectral-domain optical coherence tomography (OCT) scans (Leica, Chicago, IL, USA) of the optic nerve head were acquired from a colony of 50 adult rhesus monkeys suspected of having high prevalence of glaucoma. The RNFL-T was analyzed globally and in quadrants using a semi-automated segmentation software. From a set of 100 eyes, 18 eyes with the thinnest global RNFL-T were selected as the study group and 18 eyes with RNFL-T values around the 50th percentile were used as controls. A previously described automated segmentation algorithm was used for LC microstructure analysis. Parameters included beam thickness, pore diameter and their ratio (beam-to-pore ratio [BPR]), pore area and shape parameters, beam and pore volume, and connective tissue volume fraction (CTVF; beam volume/total volume). The LC microstructure was analyzed globally and in the following volumetric sectors: quadrants, central and peripheral lamina, and three depth slabs (anterior, middle, and posterior). Results: Although no significant difference was detected between groups for age, weight, or disc size, the study group had significantly thinner RNFL than the control group (P < 0.01). The study group had significantly smaller global and sectoral pore diameter and larger BPR compared with the control group. Across eyes, the global RNFL-T was associated positively with pore diameter globally. BPR and CTVF were significantly and negatively associated with the corresponding RNFL-T in the superior quadrant. Conclusions: Global and sectoral microstructural differences were detected when comparing thin and normal RNFL-T eyes. Whether these LC differences are the cause of RNFL damage or the result of remodeling of the LC requires further investigation. Translational Relevance: Our findings indicate structural alterations in the LC of NHP exhibiting natural thinning of the RNFL, a common characteristic of glaucomatous damage.

Contributions and future potential of animal models for geroscience research on sensory systems.

Sensory systems mediate our social interactions, food intake, livelihoods, and other essential daily functions. Age-related decline and disease in sensory systems pose a significant challenge to healthy aging. Research on sensory decline in humans is informative but can often be difficult, subject to sampling bias, and influenced by environmental variation. Study of animal models, including mice, rats, rabbits, pigs, cats, dogs, and non-human primates, plays a complementary role in biomedical research, offering advantages such as controlled conditions and shorter lifespans for longitudinal study. Various species offer different advantages and limitations but have provided key insights in geroscience research. Here we review research on age-related decline and disease in vision, hearing, olfaction, taste, and touch. For each sense, we provide an epidemiological overview of impairment in humans, describing the physiological processes and diseases for each sense. We then discuss contributions made by research on animal models and ideas for future research. We additionally highlight the need for integrative, multimodal research across the senses as well as across disciplines. Long-term studies spanning multiple generations, including on species with longer life spans, are also highly valuable. Overall, integrative studies of appropriate animal models have high translational potential for clinical applications, the development of novel diagnostics, therapies, and medical interventions and future research will continue to close gaps in these areas. Research on animal models to improve understanding of the biology of the aging senses and improve the healthspan and additional research on sensory systems hold special promise for new breakthroughs.

Age-Related Differences in Ocular Features of a Naturalistic Free-Ranging Population of Rhesus Macaques.

Purpose: Rhesus macaques (Macaca mulatta) are the premier nonhuman primate model for studying human health and disease. We investigated if age was associated with clinically relevant ocular features in a large cohort of free-ranging rhesus macaques from Cayo Santiago, Puerto Rico. Methods: We evaluated 120 rhesus macaques (73 males, 47 females) from 0 to 29 years old (mean ± SD: 12.6 ± 6.4) from September to December 2021. The ophthalmic evaluation included intraocular pressure (IOP) assessment, corneal pachymetry, biomicroscopy, A-scan biometry, automated refraction, and fundus photography after pupil dilation. The associations of age with the outcomes were investigated through multilevel mixed-effects models adjusted for sex and weight. Results: On average, IOP, pachymetry, axial length, and automated refraction spherical equivalent were 18.37 ± 4.68 mmHg, 474.43 ± 32.21 µm, 19.49 ± 1.24 mm, and 0.30 ± 1.70 diopters (D), respectively. Age was significantly associated with pachymetry (ß coefficient = -1.20; 95% confidence interval [CI], -2.27 to -0.14; P = 0.026), axial length (ß coefficient = 0.03; 95% CI, 0.01 to 0.05; P = 0.002), and spherical equivalent (ß coefficient = -0.12; 95% CI, -0.22 to -0.02; P = 0.015). No association was detected between age and IOP. The prevalence of cataracts in either eye was 10.83% (95% CI, 6.34-17.89) and was significantly associated with age (odds ratio [OR] = 1.20; 95% CI, 1.06-1.36; P = 0.004). Retinal drusen in either eye was observed in 15.00% (95% CI, 9.60-22.68) of animals, which was also significantly associated with age (OR = 1.14; 95% CI, 1.02-1.27; P = 0.020). Conclusions: Rhesus macaques exhibit age-related ocular associations similar to those observed in human aging, including decreased corneal thickness, increased axial length, myopic shift, and higher prevalence of cataract and retinal drusen.

Violent behavior, perceived safety, and assault experiences among adolescents: results from the Brazilian National Adolescent School-based Health Survey

Objective To investigate factors associated with violent behavior in a large nationally representative sample of Brazilian adolescents. Methods The data were derived from the 2015 National Adolescent School-based Health Survey (Pesquisa Nacional de Saúde do Escolar [PeNSE]). The independent variables of interest included feelings of safety while on the way to and at school. The outcome was violent behavior, including bullying. Logistic regression models were developed to examine the relationship between violent behavior and each independent and control variable. Results In the adjusted regression model, male sex (aOR: 1.75; 95%CI 1.65-1.86), being assaulted by a family member (aOR: 1.74; 95%CI 1.59-1.90), and being assaulted in the past year (aOR: 1.70; 95%CI 1.57-1.85) all increased the chance of violent behavior. Feeling safe on the way to school (aOR: 0.82; 95%CI 0.74-0.92) and at school (aOR: 0.82; 95%CI 0.73-0.92) reduced the chance of violent behavior. Conclusion This study extends the body of literature on violent behavior among adolescents, demonstrating a correlation between school, domestic, family, or community violence and violent behavior. Our research supports the idea that adolescents who experience violence act violently with greater frequency. This finding has significant implications for pediatricians, child psychiatrists and psychologists, other health care professionals, school professionals, and other professionals involved in adolescent health. School professionals must be prepared to identify adolescents with violent behavior due to its potential consequences for their mental and physical health.

Violent behavior, perceived safety, and assault experiences among adolescents: results from the Brazilian National Adolescent School-based Health Survey.

OBJECTIVE: To investigate factors associated with violent behavior in a large nationally representative sample of Brazilian adolescents. METHODS: The data were derived from the 2015 National Adolescent School-based Health Survey (Pesquisa Nacional de Saúde do Escolar [PeNSE]). The independent variables of interest included feelings of safety while on the way to and at school. The outcome was violent behavior, including bullying. Logistic regression models were developed to examine the relationship between violent behavior and each independent and control variable. RESULTS: In the adjusted regression model, male sex (aOR: 1.75; 95%CI 1.65-1.86), being assaulted by a family member (aOR: 1.74; 95%CI 1.59-1.90), and being assaulted in the past year (aOR: 1.70; 95%CI 1.57-1.85) all increased the chance of violent behavior. Feeling safe on the way to school (aOR: 0.82; 95%CI 0.74-0.92) and at school (aOR: 0.82; 95%CI 0.73-0.92) reduced the chance of violent behavior. CONCLUSIONS: This study extends the body of literature on violent behavior among adolescents, demonstrating a correlation between school, domestic, family, or community violence and violent behavior. Our research supports the idea that adolescents who experience violence act violently with greater frequency. This finding has significant implications for pediatricians, child psychiatrists and psychologists, other health care professionals, school professionals, and other professionals involved in adolescent health. School professionals must be prepared to identify adolescents with violent behavior due to its potential consequences for their mental and physical health.

Prevalence of ocular findings regardless of visual acuity status in older adults from the Brazilian Amazon Region.

Recently, it has been recommended that population-based studies report not only frequencies of vision impairment and blindness but also any ocular abnormalities that might lead an individual to seek for eyecare services. The current study aimed to determine prevalence of ocular findings regardless of visual acuity (VA) status in older adults from the Brazilian Amazon Region. Disturbances were grouped into: Eyelids; Anterior Segment; Posterior Segment; Increased intraocular pressure; and Overall Globe. The presence of an ocular finding was considered positive when any abnormality was noted, regardless of VA. Refractive errors were not considered. A total 2384 eligible persons were enumerated and 2041 (85.6%) examined. The prevalence of ocular disturbances in either eye was 87.0% and was associated with male gender, older age, lower education, and rural residence. Overall, main findings were pterygium, cataract, and pinguecula, occurring in 58.8%, 45.4% and 17.4%, respectively. Among individuals with 20/20 VA in both eyes, the most frequent findings were pterygium, pinguecula, and glaucoma cupping, occurring in 47.4%, 31.2% and 6.5%, respectively. The high prevalence of ocular findings observed in this population reinforces that different conditions might not immediately decrease VA but can indicate risk and/or discomfort symptoms and should be considered when planning public health ophthalmic services.

Grating Visual Acuity in phakic, aphakic, and pseudophakic Poodles.

OBJECTIVE: To compare the grating visual acuity (VA) measured by visual evoked potentials (VEP) in phakic, aphakic, and pseudophakic Poodles. ANIMALS STUDIED: Thirty-six Poodle dogs aged from 4 to 14 years. PROCEDURES: Animals were allocated into three different groups according to their lens status: phakic group (n = 12), aphakic group (n = 12), and pseudophakic group (n = 12). Grating VA was measured in cycles/degree (cpd) in all animals using the electrodiagnosis system Roland RETIport® in a dark room without using any mydriatic, sedative, or anesthetic drugs. RESULTS: The mean grating VA in the phakic, aphakic, and pseudophakic groups was 5.9 ± 1.0 cpd (20/102-Snellen equivalent), 2.6 ± 0.7 cpd (20/231), and 5.2 ± 1.1 cpd (20/116), respectively. The VA from aphakic eyes was significantly lower when compared to the phakic and pseudophakic eyes (P < .05). There was no significant difference in VA between phakic and pseudophakic eyes. CONCLUSIONS: The VEP is a useful tool for the evaluation of grating visual acuity in canines. The study showed that IOL implantation following phacoemulsification results in improved VA as measured by VEP compared to that of the aphakic eye and resulted in VA that was similar to that of the normal eye.

Pterygium in adults from the Brazilian Amazon Region: prevalence, visual status and refractive errors.

AIMS: To determine prevalence of pterygium, its role as main cause of unilateral and bilateral visual impairment and blindness and its impact on refractive errors from adults living in a high ultraviolet exposure area in the Brazilian Amazon Region. METHODS: Cluster sampling was used in randomly selecting subjects ≥45 years of age from urban and rural areas of Parintins city. Eligible subjects were enumerated through a door-to-door household survey and invited for an eye exam including refraction. Pterygium was assessed considering location (nasal, temporal or both) and size (<3 mm or ≥3 mm reaching or not pupillary margin). RESULTS: A total of 2384 persons were enumerated and 2041 (85.6%) were examined. Prevalence of pterygium was 58.8% (95% CI 53.8% to 63.7%) and associated with male gender (OR=1.63; 95% CI 1.37 to 1.94; p=0.001), while higher education was a protective factor (OR=0.63; 95% CI 0.44 to 0.92; p=0.018). Older age and rural residence were associated with pterygium ≥3 mm reaching or not pupillary margin, while higher education was a protective factor for pterygium ≥3 mm reaching pupillary margin. Prevalence of pterygium as cause of visual impairment and blindness was 14.3% and 3.9%, respectively. Significantly higher hyperopic refractive errors were found in eyes with pterygium ≥3 mm reaching or not pupillary margin. CONCLUSIONS: Pterygium was highly prevalent and the second cause of visual impairment and blindness after provision of refractive correction. Risk factors for pterygium were male gender, advanced age, lower education and rural residency. Strategies to provide pterygium early detection and proper management should be considered by healthcare authorities in this population.

Prevalence and Causes of Visual Impairment and Blindness in Adults Aged 45 Years and Older from Parintins: The Brazilian Amazon Region Eye Survey.

Purpose: To determine the prevalence and causes of visual impairment and blindness in adults aged 45 years and older from Parintins, Brazilian Amazon Region. Methods: A random cluster sampling method was used to identify subjects 45 years of age and older from urban and rural census sectors of Parintins city, Amazonas State, from March 2014 to May 2015. Participants underwent a detailed ocular examination, including presenting (PVA) and best corrected visual acuity (BCVA). The main cause of PVA<20/32 per eye was determined. Results: A total of 2384 subjects were enumerated and 2041 (85.6%) examined. The prevalence of presenting mild visual impairment - MiVI (<20/32 - ≥20/63) in the better-seeing eye was 17.0% [95% CI: 15.3-18.7%], and 8.5% [95% CI: 7.3-9.7%] with best correction. The prevalence of presenting moderate visual impairment - MVI (<20/63 - ≥20/200) was 18.4% [95% CI: 16.2-20.6%], and 6.9% [95% CI: 5.8-8.0%] with best correction. The prevalence of presenting bilateral VA <20/200 was 4.3% [95% CI: 3.6-5.0%], and 3.3% [95% CI: 2.5-4.0%] with best correction and increased with older age. Cataract (47.8%) and glaucoma (7.5%) were its main causes. In less severely affected eyes, uncorrected refractive errors (MVI: 42.6%; MiVI: 79.0%), cataract (MVI: 40.6%; MiVI: 13.7%) and pterygium (MVI: 7.6%; MiVI: 2.7%) were the main causes. Conclusions: Most cases of visual impairment in Parintins are either preventable or treatable, and public health initiatives should target cataract surgical services and refraction with spectacle provision.

Vision Status in Older Adults: The Brazilian Amazon Region Eye Survey.

Older adults living in remote areas with limited access to health services are at higher risk to develop visual impairment and blindness. We conducted a population-based survey to determine the vision status in subjects 45 years of age and older from urban and rural areas of Parintins city, Brazilian Amazon Region. Participants underwent ophthalmic examination, including uncorrected (UCVA), presenting (PVA) and best-corrected visual acuity (BCVA). Vision status was described as lines of visual acuity (VA) impairment and lines of VA improvement from UCVA to BCVA and from PVA to BCVA in the better-seeing eye. A total of 2384 subjects were enumerated, 2041 (85.6%) were examined, with reliable VA measurements obtained from 2025 participants. Vision status in lines of VA impairment was (mean ± standard deviation): 3.44 ± 3.53 for UCVA, 2.85 ± 3.52 for PVA and 1.50 ± 3.51 for BCVA. Female gender, older age and lower education were associated with ≥6 lines of UCVA impairment. Lines of improvement ≥3 was found in 626 (30.9%) participants and associated with female gender and rural residency. In conclusion, a third of participants could have at least three lines of VA improvement with proper refraction. Strategies to improve access to eye care and affordable glasses are needed.