Evaluation of magnesium sulfate as an adjuvant in sub-Tenon anesthesia for cataract surgery: A prospective, randomized controlled trial.

Purpose: To evaluate the efficacy, safety, and satisfaction for the use of adjuvant; magnesium sulfate (MgSO4) in sub-Tenon anesthesia for cataract surgery. Methods: This single centered randomized, double blind trial was held in 2021 after approval of ethical committee at the Eye Hospital, Riyadh, Saudi Arabia. Cataract patients to be operated using local anesthesia were randomly assigned to two groups; Group magnesium sulfate (MS) received 50 mg/0.5 ml of magnesium sulfate and Group normal saline (NS) received 0.5 ml of normal saline added to the standard mixture, respectively. Absence of eyelid dropping and akinesia of the globe at different time after anesthesia were considered as ineffective anesthesia. The age and sex-adjusted generalized estimating equation (GEE) analysis was carried out. Complications, patient's and surgeon's satisfaction were also compared. Results: Each group had 100 cataract patients. Effectiveness of block was not significantly different in two groups (adjusted odds ratio, 0.90; 95% confidence interval [CI], 0.62, 1.31; P = 0.594). The likelihood of "no eye-opening" significantly increased with time (adjusted odds ratio, 1.26; 95% CI, 1.18-1.34; P < 0.001). Subconjunctival bleeding was significantly higher in the MS versus NS Group (36 of 98 [36.7%] vs. 11 of 102 [10.8%], P < 0.001). Chemosis was not significantly different between the groups (P = 0.95). Patient's satisfaction score was very good (9/10) but slightly higher in NS group than MS (P = 0.001) while surgeon's satisfaction score was similar in both groups (P = 0.149). Conclusions: Although safe, adding 50 mg of magnesium sulfate did not improve the effect of sub-Tenon anesthesia for cataract surgery. Risk of subconjunctival bleeding was higher in cataract patients operated using MgSO4 compared to those managed with the conventional sub-Tenon anesthetic.

Association between vitamin B12 levels and cognitive impairment in older adults.

INTRODUCTION: Whether vitamin B12 deficiency is associated with cognitive impairment remains controversial. OBJECTIVE: To determine the association between vitamin B12 serum levels and cognitive performance. METHODS: Two-hundred and forty-one adults aged ≥ 60 years who had serum vitamin B12 serum levels measurement were included. Physical and cognitive evaluation was carried out, and three groups were formed: normal cognition (NC), mild cognitive impairment (MCI) and dementia. Vitamin B12 levels were classified as sufficiency (> 400 pg/mL), subclinical deficiency (201-400 pg/mL), and absolute deficiency (≤ 200 pg/mL). Multivariate linear regression analysis was used to evaluate the association between cognitive function and vitamin B12 levels after controlling for confounding variables. RESULTS: Mean age was 81.4 ± 8.0 years; 68% were females; 17.8 % and 39.8% had absolute and subclinical vitamin B12 deficiency, respectively; 80 individuals (33%) met the criteria for MCI, and 70 (29%), for dementia. Those with MCI and dementia had lower vitamin B12 levels in comparison with those with NC after adjusting for age, gender and educational level (p = 0.019). CONCLUSIONS: A statistically significant association was observed between global cognitive performance and levels of vitamin B12.

INTRODUCCIÓN: Aún es controversial si la deficiencia de vitamina B12 se asocia a alteraciones cognitivas. OBJETIVO: Conocer la asociación entre los niveles séricos de vitamina B12 y el desempeño cognitivo. MÉTODOS: Se incluyeron 241 personas ≥ 60 años con medición de niveles séricos de vitamina B12. Se realizó evaluación física y cognitiva y se formaron tres grupos: cognición normal (CN), deterioro cognitivo leve (DCL) y demencia. Los niveles de vitamina B12 se clasificaron en suficiencia (> 400 pg/mL), deficiencia subclínica (201-400 pg/mL) y deficiencia absoluta (≤ 200 pg/mL). Se realizó análisis de regresión lineal multivariado para evaluar la asociación entre función cognitiva y niveles de vitamina B12 después de controlar las variables confusoras. RESULTADOS: La media de edad fue 81.4 ± 8.0 años; 68 % fue del sexo femenino; 17.8 y 39.8 % presentaron deficiencia absoluta y subclínica de vitamina B12; 80 individuos (33 %) cumplieron los criterios de DCL y 70 (29 %), de demencia. Después de ajustar por edad, sexo y escolaridad, los sujetos con DCL y demencia tuvieron niveles más bajos de vitamina B12 comparados con aquellos con CN (p = 0.019). CONCLUSIONES: Se observó asociación estadísticamente significativa entre el desempeño cognitivo global y los niveles bajos de vitamina B12.

Asociación entre los niveles de vitamina B12 y el deterioro cognitivo en personas mayores / Association between vitamin B12 levels and cognitive impairment in older adults

Resumen Introducción: Aún es controversial si la deficiencia de vitamina B12 se asocia a alteraciones cognitivas. Objetivo: Conocer la asociación entre los niveles séricos de vitamina B12 y el desempeño cognitivo. Métodos: Se incluyeron 241 personas ≥ 60 años con medición de niveles séricos de vitamina B12. Se realizó evaluación física y cognitiva y se formaron tres grupos: cognición normal (CN), deterioro cognitivo leve (DCL) y demencia. Los niveles de vitamina B12 se clasificaron en suficiencia (> 400 pg/mL), deficiencia subclínica (201-400 pg/mL) y deficiencia absoluta (≤ 200 pg/mL). Se realizó análisis de regresión lineal multivariado para evaluar la asociación entre función cognitiva y niveles de vitamina B12 después de controlar las variables confusoras. Resultados: La media de edad fue 81.4 ± 8.0 años; 68 % fue del sexo femenino; 17.8 y 39.8 % presentaron deficiencia absoluta y subclínica de vitamina B12; 80 individuos (33 %) cumplieron los criterios de DCL y 70 (29 %), de demencia. Después de ajustar por edad, sexo y escolaridad, los sujetos con DCL y demencia tuvieron niveles más bajos de vitamina B12 comparados con aquellos con CN (p = 0.019). Conclusiones: Se observó asociación estadísticamente significativa entre el desempeño cognitivo global y los niveles bajos de vitamina B12.

Abstract Introduction: Whether vitamin B12 deficiency is associated with cognitive impairment remains controversial. Objective: To determine the association between vitamin B12 serum levels and cognitive performance. Methods: Two-hundred and forty-one adults aged ≥ 60 years who had serum vitamin B12 serum levels measurement were included. Physical and cognitive evaluation was carried out, and three groups were formed: normal cognition (NC), mild cognitive impairment (MCI) and dementia. Vitamin B12 levels were classified as sufficiency (> 400 pg/mL), subclinical deficiency (201-400 pg/mL), and absolute deficiency (≤ 200 pg/mL). Multivariate linear regression analysis was used to evaluate the association between cognitive function and vitamin B12 levels after controlling for confounding variables. Results: Mean age was 81.4 ± 8.0 years; 68% were females; 17.8 % and 39.8% had absolute and subclinical vitamin B12 deficiency, respectively; 80 individuals (33%) met the criteria for MCI, and 70 (29%), for dementia. Those with MCI and dementia had lower vitamin B12 levels in comparison with those with NC after adjusting for age, gender and educational level (p = 0.019). Conclusions: A statistically significant association was observed between global cognitive performance and levels of vitamin B12.

Implementation of telemedicine screening for retinopathy of prematurity in rural areas in Guatemala.

PURPOSE: To report findings of a telemedicine retinopathy of prematurity (ROP) screening program in six neonatal units in rural areas of Guatemala, using a portable, noncontact, 40° field digital fundus camera (Pictor Plus) operated by trained technicians. METHODS: National ROP Program Guidelines screening criteria were used: gestational age <36 weeks and/or birth weight (BW) <2000 g, or GA <36 weeks but BW ≥2000 g, with qualifying medical history. Retinal images were obtained by two technicians and graded by ophthalmologists experienced in ROP. Infants with signs of pre-plus or plus disease in one or both eyes were referred for clinical examination. Screening was stopped when retinal vessels in anterior zone II were normal on two successive evaluations or the infant had reached 45 week's postmenstrual age. RESULTS: A total of 418 of 1,890 eligible infants (22.1%) were screened. Mean GA was 33.9 ± 2.2 weeks (range, 27-36), and mean BW 1728.3 ± 379.3 g (range, 840-2830 g). Thirty-three infants (8.6%) developed plus or pre-plus disease, and 19 (58%) underwent ophthalmologic examination. Fifteen infants were confirmed with type 1 ROP, and 14 were treated. Mean GA of treated infants treated was 33.6 ± 3.0 weeks (range, 32-34.9), and mean BW was 1,646 ± 245.8 g (range, 1100-1774.1 g). CONCLUSIONS: Imaging with a noncontact fundus camera can facilitate detection of treatable ROP in countries with limited resources. Strengthening the health systems, including motivation and continued training of neonatal intensive care personnel is essential to improve and maintain program effectiveness. Reasons for, and interventions to address the low uptake of screening need to be explored to extend coverage of ROP screening to district hospitals in Guatemala.

Spatial aggregation of fruits explains food selection in a neotropical primate (Alouatta pigra).

The availability and spatial distribution of food resources affect animal behavior and survival. Black howler monkeys (Alouatta pigra) have a foraging strategy to balance their nutrient intake that involves mixing their consumption of leaves and fruits. The spatial aggregation of food items should impact this strategy, but how it does so is largely unknown. We quantified how leaf and fruit intake combined (here termed food set selection) was spatially aggregated in patches and how food aggregation varied across seasons. Using variograms we estimated patch diameter and with Generalized Least Square models determined the effect of food spatial aggregation on food selection. Only fruits were structured in patches in the season of highest availability (dry-season). The patches of food set selection had a diameter between 6.9 and 14 m and were explained by those of mature fruit availability which were between 18 and 19 m in diameter. Our results suggest that the spatial pattern of food selection is influenced by patches of large fruit-bearing trees, not by particular species. Fruit also occur along spatial gradients, but these do not explain food selection, suggesting that howlers maximize food intake in response to local aggregation of fruit that are limiting during certain seasons. We demonstrate how the independent spatial modelling of resources and behavior enables the definition of patches and testing their spatial relationship.

Will the SAFE strategy be sufficient to eliminate trachoma by 2020? Puzzlements and possible solutions.

Since the inception of (the Global Elimination of Blinding Trachoma) GET 2020 in 1997 and the implementation of the SAFE strategy a year later, much progress has been made toward lowering the prevalence of trachoma worldwide with elimination of the disease in some countries. However, high recurrence of trichiasis after surgery, difficulty in controlling the reemergence of infection after mass distribution of azithromycin in some communities, the incomplete understanding of environment in relation to the disease, and the difficulty in establishing the prevalence of the disease in low endemic areas are some of the issues still facing completion of the GET 2020 goals. In this narrative review, literature was searched from 1998 to January 2013 in PubMed for original studies and reviews. Reasons for these ongoing problems are discussed, and several suggestions are made as avenues for exploration in relation to improving the SAFE strategy with emphasis on improving surgical quality and management of the mass treatment with antibiotics. In addition, more research needs to be done to better understand the approach to improve sanitation, hygiene, and environment. The main conclusion of this review is that scale-up is needed for all SAFE components, and more research should be generated from communities outside of Africa and Asia.

Causes of blindness and visual impairment in Latin America.

We review what is known in each country of the Latin American region with regards to blindness and visual impairment and make some comparisons to Hispanic populations in the United States. Prevalence of blindness varied from 1.1% in Argentina to 4.1% in Guatemala in people 50 years of age and older, with the major cause being cataract. Diabetic retinopathy and glaucoma are starting to make serious inroads, although epidemiological data are limited, and age-related macular degeneration is now a concern in some populations. Infectious diseases such as trachoma and onchocerciasis are quickly diminishing. Although progress has been made, retinopathy of prematurity remains the major cause of childhood blindness. If VISION 2020 is to succeed, many more epidemiological studies will be needed to set priorities, although some can be of the Rapid Assessment of Avoidable Blindness design. Developing the infrastructure for screening and treatment of ophthalmic disease in Latin America continues to be a challenge.

Do gender inequities exist in cataract surgical coverage? Meta-analysis in Latin America.

BACKGROUND: To determine if gender inequities exist in Latin America in regard to cataract surgery. DESIGN: Meta-analysis. PARTICIPANTS: Total of 38,992 subjects participating in epidemiological surveys; summary measures were used (not patient-level data). METHODS: A literature search and knowledge of rapid assessment of cataract surgical services/rapid assessment of avoidable blindness studies carried out in Latin America found 11 studies with complete cataract surgical coverage (CSC) data. Using summary original study data, a meta-analysis (random effects model) was conducted to analyse the differences in CSC between males and females. Results were adjusted for design effect. MAIN OUTCOME MEASURES: Odds ratio (OR) of receiving cataract surgery comparing women with men. RESULTS: CSC with a visual acuity (VA) <3/60 on an eye basis showed a non-statistically significant OR of 1.01 (95% confidence intervals [CI]: 0.86-1.18) for women receiving cataract surgery in comparison with men. For VA < 6/18, a non-statistically significant OR of 0.94 (95% CI: 0.83-1.07) was obtained for women receiving cataract surgery. On a person basis at a VA of <3/60 and <6/18, non-statistically significant ORs of 1.12 (95% CI: 0.78-1.63) and 0.94 (95% CI: 0.77-1.15) were obtained for women receiving cataract surgery, respectively. Statistical heterogeneity was 0% (I(2) statistic), except for results at a VA of <3/60 on a person basis (I(2) = 30%). CONCLUSIONS: In the Latin American countries in which CSC was assessed, gender does not appear to be a significant factor in receiving cataract surgery. However, more data are required to confirm these results.

River blindness: an old disease on the brink of elimination and control.

For decades, onchocerciasis (or river blindness) was one of the most common infectious causes of blindness in the world. Primarily an infection of Africa, with limited distribution in the new world, disease due to the nematode Onchocerca volvulus is rapidly diminishing as a result of large public health campaigns targeting at risk populations in Africa and the Americas. Existing and newly-developed treatment strategies offer the chance to eliminate onchocercal ocular morbidity in some parts of the world. This article reviews these treatment strategies, current clinical and epidemiologic aspects of onchocerciasis, and the next steps toward elimination.

Cataract surgery rates in latin america: a four-year longitudinal study of 19 countries.

PURPOSE: To collect cataract surgery rates data in 19 Latin American countries over a 4-year period as data published to date have been limited. METHODS: Cataract surgery rates were obtained from National Society of Ophthalmology, National VISION 2020/Prevention of Blindness Committee and Ministry of Health representatives for each country for 2005 to 2008. Economic (gross national income per capita) and other data were collected from publicly available databases. Linear and power correlations between gross national incomes and cataract surgery rates were calculated. RESULTS: Over the study period, most countries increased their cataract surgery rates, with the largest increases observed for Venezuela (186%), Nicaragua (183%), Costa Rica (100%), Uruguay (97%), and Peru (88%). Mean cataract surgery rates for 2005, 2006, 2007, and 2008 for the ensemble of countries were 1545, 1684, 1660, and 1822 per million population, respectively, with a growth over the study period of 17.9%, concurrent with an increase of 57 million (11.5%) in the population. A good correlation between cataract surgery rate and gross national income per capita was found (P < .001). CONCLUSIONS: Although progress is being made in the region, the cataract surgery rates represent only one parameter. When they are examined in the context of cataract surgical coverage it is clear that substantial proportions of bilaterally blind persons are still not receiving surgery.

Cataract in Latin America: findings from nine recent surveys.

OBJECTIVES: To review recent data on blindness and low vision due to cataract in Latin America. METHODS: Presentation of findings from population-based prevalence surveys conducted between 1999 and 2006 in nine Latin American countries covering 30,544 people aged 50 years and older. RESULTS: Prevalence of cataract blindness in people 50 years and older ranged from 0.5% in Buenos Aires to 2.3% in four provinces of Guatemala. Low vision from cataract ranged from 0.9% in Buenos Aires to 10.7% in Piura and Tumbes Districts in Peru. Cataract surgical coverage (CSC) was good in Campinas, Brazil; low in Paraguay, Peru, and Guatemala; and moderate in the other areas. Good visual outcome after cataract surgery nearly conformed to World Health Organization (WHO) guidelines in Buenos Aires (more than 80% of operated eyes able to see 20/60 or better), but ranged from 60% to 79% in most of the other settings, and was less than 60% in Guatemala and Peru. "Unaware that treatment is possible," "contraindications," "cannot afford," and "fear of operation" were the most common explanations for failure to come forward for surgery. CONCLUSIONS: In Campinas, Brazil, cataract is fairly well controlled. In Buenos Aires, the visual outcomes after cataract surgery nearly meet WHO standards. In most countries in Latin America, however, cataract intervention needs to be intensified and visual outcome improved. Reducing the costs of cataract surgery and providing effective health education and adequate program management are essential to combat the expected increase in visual impairment due to cataract in the region.

Cataract in Latin America: findings from nine recent surveys / La catarata en América Latina: resultados de nueve encuestas recientes

OBJECTIVES: To review recent data on blindness and low vision due to cataract in Latin America. METHODS: Presentation of findings from population-based prevalence surveys conducted between 1999 and 2006 in nine Latin American countries covering 30 544 people aged 50 years and older. RESULTS: Prevalence of cataract blindness in people 50 years and older ranged from 0.5 percent in Buenos Aires to 2.3 percent in four provinces of Guatemala. Low vision from cataract ranged from 0.9 percent in Buenos Aires to 10.7 percent in Piura and Tumbes Districts in Peru. Cataract surgical coverage (CSC) was good in Campinas, Brazil; low in Paraguay, Peru, and Guatemala; and moderate in the other areas. Good visual outcome after cataract surgery nearly conformed to World Health Organization (WHO) guidelines in Buenos Aires (more than 80 percent of operated eyes able to see 20/60 or better), but ranged from 60 percent to 79 percent in most of the other settings, and was less than 60 percent in Guatemala and Peru. "Unaware that treatment is possible," "contraindications," "cannot afford," and "fear of operation" were the most common explanations for failure to come forward for surgery. CONCLUSIONS: In Campinas, Brazil, cataract is fairly well controlled. In Buenos Aires, the visual outcomes after cataract surgery nearly meet WHO standards. In most countries in Latin America, however, cataract intervention needs to be intensified and visual outcome improved. Reducing the costs of cataract surgery and providing effective health education and adequate program management are essential to combat the expected increase in visual impairment due to cataract in the region.

OBJETIVO: Hacer una revisión de los datos recientes sobre ceguera y visión reducida por catarata en América Latina. MÉTODO: Presentación de los resultados de estudios de prevalencia de base poblacional realizados entre 1999 y 2006 en nueve países latinoamericanos, que abarcaron 30 544 personas de 50 años o más. RESULTADOS: La prevalencia de ceguera por catarata en personas de 50 años o más estuvo entre 0,5 por ciento en Buenos Aires, Argentina, y 2,3 por ciento en cuatro provincias de Guatemala. La visión reducida por catarata varió entre 0,9 por ciento en Buenos Aires y 10,7 por ciento en los distritos de Piura y Tumbes, Perú. La cobertura de cirugía de catarata fue buena en Campinas, Brasil; baja en Paraguay, Perú y Guatemala; y media en el resto de las áreas. Los resultados positivos de la cirugía de catarata estuvieron muy cerca de los estándares de la Organización Mundial de la Salud (OMS) en Buenos Aires (más de 80 por ciento de los ojos operados con visión de 20/60 o mejor), pero varió entre 60 por ciento y 79 por ciento en la mayoría de los otros lugares y fue inferior a 60 por ciento en Guatemala y Perú. Las explicaciones expuestas más frecuentemente para no someterse a esta operación fueron "no saber que el tratamiento es posible", "contraindicaciones", "no poder pagarlo" y "temor a la operación". CONCLUSIONES: En Campinas, la catarata está bastante bien controlada. En Buenos Aires, la visión después de la cirugía de catarata se acerca a los estándares de la OMS. No obstante, en la mayoría de los países de América Latina las intervenciones contra la catarata deben intensificarse y sus resultados deben mejorar. Es esencial reducir el costo de la cirugía de catarata y brindar una educación sanitaria eficaz y programas adecuados para combatir el esperado aumento en los trastornos de la visión por catarata en la Región.

Guidelines on Intinerant Surgeons in the Caribbean

An Itinerant Surgeon is a physician who volunteers to work in health care systems other than his or her own. The volunteer may provide services such as consultation, special tests and surgery but, in addition, may also transmit information or goods such as books, literature, equipment and instruments. SERVICES OF AN ITINERANT OR VISITING TEAM: For any itinerant team, an advance visit is desirable to define a programme of activities. The visiting team's efforts should focus on a sustainable change in the programme for prevention of blindness in the host country through advocacy for preventitive measures, quality eye care, human resources development, infrastructure building and development of administrative proceesses.The team should work within the existing system of eye care delivery at the governmental facilities or approved non-Governmental Development Organizations(NGDOs). Any visit of foreign team is an opportunity for interviews in the media to increase public awareness in eye care, and for advocacy by the team in the governmental structure. The local eye care professionals should identify posible technical and scientific topics in which they need training, if that aspect is recognised as an important product of the visit. The World Health Organization (WHO) has developed the following guidelines for donation of equipment in order to assist donors and recipients: the donation should benefit and fully respect the wishes and authority of the recipient; the quality should be based on an expressed need by the recipient; before a donation is made: - the need for specific items and their expiration date are evaluated; - there must be assurance that it will be used for the purpose for which it is donated; - the person or group who will be responsible for receipt and distribution must be identified; - the customs regulations and shipping costs must be determined. A visiting team may also provide very valuable knowledge in organisation and establishment of processes in the different aspects of a service such as organisation of an operating room, keeping an inventory of consumable supplies, organising an appointment and record system and basic statistics. JUSTIFICATION OF A VISITING OR ITINERANT TEAM: The itinerant service should provide solutions to specific problems or gaps in: availability of services (AU) [truncated at 2500 characters]