High-temperature properties of cesium

High temperature properties of cesium - density and vapor pressure of liquid cesium, and saturation and superheat properties of cesium vapo

Secondary 12-Month Ocular Outcomes of a Phase 1 Dosing Study of Bevacizumab for Retinopathy of Prematurity

Importance Lower bevacizumab dosages are being used for type 1 retinopathy of prematurity, but there are limited data on long-term ocular outcomes with lower doses. Objective To evaluate ocular outcomes at 12 months’ corrected age for eyes that received a dose of 0.625 mg, 0.25 mg, 0.125 mg, 0.063 mg, or 0.031 mg of bevacizumab for type 1 retinopathy of prematurity. Design, Setting, and Participants This prospective cohort study used a masked, multicenter, phase 1 dose de-escalation study design and was conducted from April 2016 to October 2017. Study eyes were treated with a dose of 0.25, 0.125, 0.063, or 0.031 mg of bevacizumab; fellow eyes were treated with a dosage 1 level higher than the study eye. Additional treatment after 4 weeks was at investigator discretion. Data analysis occurred from November 2018 to March 2019. Interventions Intravitreous bevacizumab injections of 0.625 mg to 0.031 mg. Main Outcomes and Measures Visual fixation, amblyopia, alignment, nystagmus, cycloplegic refraction, and ocular examinations were assessed at 12 months’ corrected age as preplanned secondary outcomes. The primary outcome 4 weeks after treatment and secondary outcomes after 6 months’ corrected age have been previously reported. Results Forty-six of 61 infants (75%) had a 12-month follow-up examination (46 study eyes and 43 fellow eyes; median [interquartile range] birth weight, 650 [590-760] g). Of 87 eyes with a cycloplegic refraction, 12 (14% [95% CI, 7%-27%]) had myopia of more than −5.00 D spherical equivalent; 2 (2%; [95% CI, 0%-8%]) had hyperopia greater than 5.00 D spherical equivalent; and 5 infants (11% [95% CI, 4%-24%]) had anisometropia greater than 1.50 D spherical equivalent. Abnormalities of the cornea, lens, or anterior segment were reported in 1 eye (1% [95% CI, 0%-6%]), 3 eyes (3% [95% CI, 1%-10%]), and 3 eyes (3% [95% CI, 1%-10%]), respectively. Optic nerve atrophy was identified in 11 eyes (13% [95% CI, 6%-26%]), and 1 eye (1% [95% CI, 0%-6%]) had total retinal detachment. Strabismus was reported in 13 infants (30% [95% CI, 17%-45%]), manifest nystagmus in 7 infants (15% [95% CI, 6%-29%]), and amblyopia in 3 infants (7% [95% CI, 1%-18%]). Overall, 98% of infants had central fixation in each eye (44 of 45 eyes). Conclusions and Relevance In this study of low-dose bevacizumab, the secondary outcomes of high myopia, strabismus, retinal detachment, nystagmus, and other ocular abnormalities at 1 year were consistent with rates reported in other studies with higher dosages

Intravitreal anti-VEGF therapy as an adjunct to laser photocoagulation for severe aggressive posterior retinopathy of prematurity

AbstractPurposeThe aim of the study was to evaluate the role of anti-VEGF therapy as an adjunct to laser ablation therapy in severe aggressive posterior retinopaty of prematurity (AP-ROP).MethodsMedical records of premature infants with a primary diagnosis of AP-ROP treated with 0.625mg/0.025ml intravitreal bevacizumab (IVB) in addition to standard laser photocoagulation as a salvage therapy or primarily combined with laser in a university clinic were reviewed, retrospectively. The anatomical results and complications were evaluated after treatment.Results15 eyes of 9 patients with a mean gestational age of 28.3 weeks (range, 26–31w) and mean birth weight of 1090g (range, 860–1330g) were included in the study. They all had Zone 1 or posterior Zone 2 plus disease staging between severe 3 and 4a. Twelve eyes were treatment naive at the beginning. The mean follow-up was 19.5±11.8 months (range, 11–40 months). The disease regressed totally in 6 eyes (40%), stayed stable as stage 4a in 1 eye (6.7%), progressed to and stabilized at stage 4a in 3 eyes (20%) and progressed to stage 5 in 3 eyes (20%) within 7–10 days. Two eyes (13.3%) developed hypotony and cataract.ConclusionThe association of IVB and laser ablation might decrease the progression rate in severe AP-ROP. Prompt regression of iris neovascularization encourages its use in cases with pupillary rigidity to allow for laser treatment. When used as a salvage therapy it may not change the overall result dramatically

A review of cataract in stable and conflict zones in Africa

Aim. To review and explore cataract prevalence in stable and unstable countries by examining published and unpublished ocular literature about Africa from 1980 onwards. Methods. Searches using OVID, Proquest Dissertations, WHO, and Ebsco Host were done. The review was restricted to articles utilizing WHO definitions of blindness and low vision. Random cluster sampling technique with a minimum sample size of 1,500, and reporting causes of blindness categorized by age and gender were inclusion considerations in the selected articles. Results. Blindness and low vision increased with conflict. Women and the elderly were more likely to have vision impairing cataract. Cataract was the leading cause of blindness; the prevalence range was 22%–81% for the reviewed nations. Conclusion. Instability was connected to higher cataract prevalence and worse visual outcome across all characteristics examined except cataract surgical rates

Nutritional blindness in Africa

Nutritional blindness is loss of useful vision resulting from vitamin deficiency. A malnutrition Xerophthalmia means all the ocular manifestations of inadequate metabolism of vitamin A, nutritional blindness being the end result of the most severe cases. The estimated overall prevalence of nutritional blindness in Africa is very low, below the WHO levels of significance, although isolated clusters of locally high prevalence exist, usually in arid, sparsely-populated regions. The peak age group affected is 2-year olds, with most nutritional blindness having its effect before age 6 years. Xerophthalmia may be considered as a serious side effect of protein-energy malnutrition (PEM). When associated with corneal sequelae of xerophthalmia, PEM has an estimated overall mortality of 50%. Intervention programs, therefore, are more appropriately aimed at the broader condition of life-threatening PEM than at the specifically vision-threatening problem of xerophthalmia. Parameters of significant prevalence detection are discussed, and the relative merits of different forms of vitamin A-specific intervention programs are weighed.

Visual disability and blindness secondary to refractive errors in Africa

Optical defects of the light-focusing apparatus of the eye are called errors of refraction. They are responsible for 13% of all significant vision loss in Kenya, ranking third of all causes, after cataract and trachoma. As the overall prevalence of such visual impairment in the Country is 3.7%, roughly 0.5% of the population can be said to need spectacles to obtain normal vision. The comparable figure for secondary school children in Nigeria has been found to be 2.4%. In addition, patients require special spectacles after cataract surgery to obtain adequate vision; without such spectacles these patients are still 'blind' by World Health Organization criteria. These glasses can be obtained through mission societies and various charitable organizations for as little as $5 per pair, and can be manufactured locally with available ophthalmic manpower and technology. Alternatives to spectacles such as contact lenses, intra-ocular lenses and Kerato-refractive surgery are not suitable for use in developing Countries.