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This Issue At A Glance
This Issue At A Glance
Ophthalmology Volume 115, Number 11, November 2008
AMD Genetic Variant Harbored Within HtrA1 Findings from multiple independent samples of age-related macular degeneration (AMD) cases in the United States and Australia have confirmed the HtrA1 promoter polymorphism is a global genetic marker for AMD in Caucasian populations. In this clinic-based and population-based case-control study, Tuo et al (p. 1891) obtained DNA samples from 805 AMD cases and 921 controls from The Eye Clinic of the National Eye Institute, Age-Related Eye Diseases Study, Blue Mountain Eye Study Cohort, and Minnesota Lions Eye Bank. Strong associations of the HtrA1 risk allele (A) with AMD were present in all sample sets. This association was also noted for central geographic atrophy and neovascular AMD. The combination of the HtrA1 and complement factor H risk alleles increased AMD susceptibility as did the combination of the HtrA1 risk allele and smoking. The authors conclude the risk of advanced AMD increases with the presence of risk factors from HtrA1 combined with either complement factor H risk alleles or a history of smoking.
Corneal Disease Staging at Presentation in Acanthamoeba Keratitis Tu et al (p. 1998) have found that corneal disease staging at presentation in patients with Acanthamoeba keratitis (AK) is highly predictive of worse outcomes. Through a retrospective medical records review, investigators collected patient data on clinical characteristics, treatment methods, and final visual outcome of 72 eyes of 65 patients with AK. The main outcome measure was a final visual outcome worse than 20/25. They found that deep stromal involvement and/or presence of a ring infiltrate at presentation was independently associated with worse visual outcome. In addition, unlike previous reports, while symptom duration before diagnosis was statistically predictive of disease stage a presentation, it was not predictive of final visual outcome in this study. The researchers conclude that slit-lamp grading of corneal disease or depth of involvement at presentation in AK patients is strongly associated with final visual outcomes. These findings provide a practical method for clinicians to identify high-risk patients who may require more aggressive medical and surgical therapy.
Effect of IOP-Reducing Treatment on Development of Disc Hemorrhages Despite a clear association between disc hemorrhages and glaucoma progression, Bengtsson et al (p. 2044) were unable to demonstrate any effect of intraocular pressure (IOP)–reducing treatment on the presence or frequency of disc hemorrhages in Early Manifest Glaucoma Trial patients. For about 11 years, investigators followed 129 newly detected glaucoma patients treated with argon laser trabeculoplasty plus betaxolol, and 126 newly detected glaucoma patients with no initial treatment. Disc hemorrhages, identified in approximately 55% of all patients, were equally common among treated and control patients. There was no relationship between disc hemorrhages and the
extent of IOP degrease in treated patients. Instead, findings suggested that disc hemorrhages were related to the level of IOP at follow-up rather than to the amount of IOP reduction. The authors make 2 conclusions. First, disc hemorrhages do not necessarily indicate that a patient is receiving inappropriate IOP-lowering treatment. Second, glaucoma progression cannot be totally halted by IOP reduction in eyes with disc hemorrhages.
Calcium Antagonist Nilvadipine Studied in Glaucoma Patients Nilvadipine is a dihydrophyridine calcium antagonist registered in Japan as a systemic hypotensive drug. Research has shown this calcium antagonist may have some advantages as a potential vasodilator in ocular neural tissues. Koseki et al (p. 2049) conducted a randomized study looking at the effects of oral nilvadipine on visual field performance and ocular circulation in open-angle glaucoma (OAG) in patients with low-normal intraocular pressure (IOP). Of the 33 patients enrolled, 17 received nilvadipine (2 mg twice daily) and 16 received placebo; 13 in each group finished the study. During the 3-year study period, IOP averaged 12.6 mmHg in the nilvadipine group and 12.8 mmHg in the placebo group. The nilvadiprine group experienced a slightly slowed visual field progression and maintained the optic disc rim. In addition, the posterior choroidal circulation increased in these patients. No serious systemic side effects were associated with the calcium antagonist. The authors conclude that nilvadipine may be a relatively safe ophthalmic calcium antagonist in OAG patients with low-normal IOP.
No Differences Between Near, Distance Activities with Amblyopia Patching In a randomized, clinical trial involving 425 children ages 3 to ⬍7 years old with amblyopia, The Pediatric Eye Disease Investigator Group (p. 2071) has found no difference in visual acuity improvement between children who performed common near activities and those who performed distance activities during patching treatment. The children with amblyopia (20/40 to 20/400) were randomized to 2 hours of patching per day with near activities or with distance activities. At 8 weeks, improvement in amblyopic eye visual acuity averaged 2.6 lines in the distance activities group and 2.5 lines in the near activities group–and remained statistically similar at the 17-week visits. A secondary finding was that children with severe amblyopia (20/100 to 20/400) showed improvement in visual acuity with 2 hours per day of prescribed patching regardless of near or distance activities. The researchers would not recommend prescribing specific near activities for children undergoing patching for amblyopia. However, 2 hours of patching each day represents an option to treat severe amblyopia.
Lori Baker Schena and John Kerrison, MD
Ophthalmology Volume 115, Number 11, November 2008
AMD Genetic Variant Harbored Within HtrA1 Findings from multiple independent samples of age-related macular degeneration (AMD) cases in the United States and Australia have confirmed the HtrA1 promoter polymorphism is a global genetic marker for AMD in Caucasian populations. In this clinic-based and population-based case-control study, Tuo et al (p. 1891) obtained DNA samples from 805 AMD cases and 921 controls from The Eye Clinic of the National Eye Institute, Age-Related Eye Diseases Study, Blue Mountain Eye Study Cohort, and Minnesota Lions Eye Bank. Strong associations of the HtrA1 risk allele (A) with AMD were present in all sample sets. This association was also noted for central geographic atrophy and neovascular AMD. The combination of the HtrA1 and complement factor H risk alleles increased AMD susceptibility as did the combination of the HtrA1 risk allele and smoking. The authors conclude the risk of advanced AMD increases with the presence of risk factors from HtrA1 combined with either complement factor H risk alleles or a history of smoking.
Corneal Disease Staging at Presentation in Acanthamoeba Keratitis Tu et al (p. 1998) have found that corneal disease staging at presentation in patients with Acanthamoeba keratitis (AK) is highly predictive of worse outcomes. Through a retrospective medical records review, investigators collected patient data on clinical characteristics, treatment methods, and final visual outcome of 72 eyes of 65 patients with AK. The main outcome measure was a final visual outcome worse than 20/25. They found that deep stromal involvement and/or presence of a ring infiltrate at presentation was independently associated with worse visual outcome. In addition, unlike previous reports, while symptom duration before diagnosis was statistically predictive of disease stage a presentation, it was not predictive of final visual outcome in this study. The researchers conclude that slit-lamp grading of corneal disease or depth of involvement at presentation in AK patients is strongly associated with final visual outcomes. These findings provide a practical method for clinicians to identify high-risk patients who may require more aggressive medical and surgical therapy.
Effect of IOP-Reducing Treatment on Development of Disc Hemorrhages Despite a clear association between disc hemorrhages and glaucoma progression, Bengtsson et al (p. 2044) were unable to demonstrate any effect of intraocular pressure (IOP)–reducing treatment on the presence or frequency of disc hemorrhages in Early Manifest Glaucoma Trial patients. For about 11 years, investigators followed 129 newly detected glaucoma patients treated with argon laser trabeculoplasty plus betaxolol, and 126 newly detected glaucoma patients with no initial treatment. Disc hemorrhages, identified in approximately 55% of all patients, were equally common among treated and control patients. There was no relationship between disc hemorrhages and the
extent of IOP degrease in treated patients. Instead, findings suggested that disc hemorrhages were related to the level of IOP at follow-up rather than to the amount of IOP reduction. The authors make 2 conclusions. First, disc hemorrhages do not necessarily indicate that a patient is receiving inappropriate IOP-lowering treatment. Second, glaucoma progression cannot be totally halted by IOP reduction in eyes with disc hemorrhages.
Calcium Antagonist Nilvadipine Studied in Glaucoma Patients Nilvadipine is a dihydrophyridine calcium antagonist registered in Japan as a systemic hypotensive drug. Research has shown this calcium antagonist may have some advantages as a potential vasodilator in ocular neural tissues. Koseki et al (p. 2049) conducted a randomized study looking at the effects of oral nilvadipine on visual field performance and ocular circulation in open-angle glaucoma (OAG) in patients with low-normal intraocular pressure (IOP). Of the 33 patients enrolled, 17 received nilvadipine (2 mg twice daily) and 16 received placebo; 13 in each group finished the study. During the 3-year study period, IOP averaged 12.6 mmHg in the nilvadipine group and 12.8 mmHg in the placebo group. The nilvadiprine group experienced a slightly slowed visual field progression and maintained the optic disc rim. In addition, the posterior choroidal circulation increased in these patients. No serious systemic side effects were associated with the calcium antagonist. The authors conclude that nilvadipine may be a relatively safe ophthalmic calcium antagonist in OAG patients with low-normal IOP.
No Differences Between Near, Distance Activities with Amblyopia Patching In a randomized, clinical trial involving 425 children ages 3 to ⬍7 years old with amblyopia, The Pediatric Eye Disease Investigator Group (p. 2071) has found no difference in visual acuity improvement between children who performed common near activities and those who performed distance activities during patching treatment. The children with amblyopia (20/40 to 20/400) were randomized to 2 hours of patching per day with near activities or with distance activities. At 8 weeks, improvement in amblyopic eye visual acuity averaged 2.6 lines in the distance activities group and 2.5 lines in the near activities group–and remained statistically similar at the 17-week visits. A secondary finding was that children with severe amblyopia (20/100 to 20/400) showed improvement in visual acuity with 2 hours per day of prescribed patching regardless of near or distance activities. The researchers would not recommend prescribing specific near activities for children undergoing patching for amblyopia. However, 2 hours of patching each day represents an option to treat severe amblyopia.
Lori Baker Schena and John Kerrison, MD