PKP in chronic or delayed-onset mustard gas keratitis should be considered as a high-risk graft; however, with appropriate management, graft clarity and visual outcomes may be favorable.

Purpose:To determine the prevalence of amblyopia and refractive errors among 7 to 12-year-old primary school children in Tehran, Iran.Methods:This population-based cross-sectional study included 2,410 randomly selected students. Visual acuity was tested using an E-chart on Yang vision tester. Refractive errors were measured by photorefractometry and cycloautorefraction. Strabismus was checked using cover test. Direct ophthalmoscopy was used to assess the anterior segment, lens opacities, red reflex and fundus. Functional amblyopia was defined as best corrected visual acuity ≤20/40 in one or both eyes with no anatomical problems.Results:Amblyopia was present in 2.3% (95% CI: 1.8% to 2.9%) of participants with no difference between the genders. Amblyopic subjects were significantly younger than non-amblyopic children (P=0.004). Overall, 15.9% of hyperopic and 5.9% of myopic cases had amblyopia. The prevalence of hyperopia ≥+2.00D, myopia ≤-0.50D, astigmatism ≥0.75D, and anisometropia (≥1.00D) was 3.5%, 4.9%, 22.6%, and 3.9%, respectively. With increasing age, the prevalence of myopia increased (P<0.001), that of hyperopia decreased (P=0.007), but astigmatism showed no change. Strabismus was found in 2.3% of cases. Strabismus (OR=17.9) and refractive errors, especially anisometropia (OR=12.87) and hyperopia (OR=11.87), were important amblyogenic risk factors.Conclusion:The high prevalence of amblyopia in our subjects in comparison to developed countries reveals the necessity of timely and sensitive screening methods. Due to the high prevalence of amblyopia among children with refractive errors, particularly high hyperopia and anisometropia, provision of glasses should be specifically attended by parents and supported by the Ministry of Health and insurance organizations.

No abstract

The prevalence of OHT was higher in cases with GO than age and sex-matched controls. Ophthalmologic examinations including intraocular pressure measurement (and if needed automated visual fields) should be regularly performed in patients with GO particularly in higher stages and those with active disease.

In spite of being statistically significant in some parts, the amounts of refractive and corneal topographic changes were not clinically remarkable. Therefore, it does not seem necessary to perform cycloplegic refraction early after horizontal rectus muscle recession; however, a precise refraction in all cases of strabismus should not be deferred later than 3 months.

Relatives of patients with KCN have a high prevalence of undiagnosed KCN. Corneal topography is important for the diagnosis of KCN and KCN suspects in family members of patients with KCN. Therefore, keratorefractive surgery should be considered cautiously in these individuals.

Marfan syndrome is an autosomal dominant genetic connective tissue disorder that results from mutations in the fibrillin-1 gene located on chromosome band 15q15–21. Fibrillin, a glycoprotein, is widely expressed throughout the body and contributes to the elasticity and force-bearing capacity of connective tissue. In the eye, fibrillin is a key constituent of the ciliary zonules, which suspend the crystalline lens in place. The zonular defect leads to ectopia lentis, which is a hallmark of Marfan ocular abnormalities and occurs in 60% to 80% of cases. Other less common ocular features of Marfan syndrome are increased axial length, astigmatism, and flat cornea. Visual function in Marfan syndrome could be affected in several ways: ectopia lentis, refractive error, amblyopia, retinal detachment, cataract, and glaucoma. Management of a subluxated lens starts with the correction of refractive error with eyeglasses in mild cases. In more severe cases, especially when the lens bisects the pupil, complete correction of refractive error is impossible without removing the subluxated lens. The best method for visual rehabilitation after lens extraction is still debated. Aphakic Artisan lens implantation at the time of subluxated lens removal results in good visual outcomes with an acceptable safety profile. Studies with longer term follow-up and larger sample populations are needed to evaluate the safety of this procedure in patients with Marfan syndrome.

Based on our study, PRK seems to be a safe, efficient, and stable surgical procedure, and if patients obtain a good result with the initial treatment, then their results are relatively stable over time.