Outdoor Recess Helps Prevent Myopia in Schoolchildren
Journal of the American Medical Association
He et al. conducted a 3-year randomized trial to test the efficacy of outdoor activity during recess and in time away from school in staving off myopia among 6-year-old students in Guangzhou, China.
Six schools, with a total of 952 students, were selected as intervention schools. These children participated in an additional 40-minute class of outdoor activities each day; moreover, their parents were encouraged to engage their children in outdoor activities after school and on weekends and holidays. Children and parents in 6 control schools (951 students) followed their usual patterns of activity.
The cumulative incidence of myopia was 30.4% among students in the intervention group versus 39.5% in the control group. The authors also found a significant difference in the 3-year change in spherical equivalent refraction in the intervention group (–1.42 D) compared with the control group (–1.59 D). Increase in axial length did not differ significantly between the 2 groups (intervention group, 0.95 mm; control group, 0.98 mm).
The authors noted that the study achieved an absolute difference of 9.1% in the incidence rate of myopia, which represents a 23% relative reduction in incident myopia after 3 years. Although this reduction was less than anticipated, it remains clinically important because children who develop myopia at an early age are at the greatest risk of progressing to high myopia (greater than or equal to –6 D) and of developing pathological myopia. However, the study also found that—despite the educational plan directed at parents in the intervention group—the time spent outdoors outside of the school day did not differ significantly between the 2 groups. Therefore, the intervention exposure was only the extra 40 minutes/day spent outdoors for 5 school days/week during the 9.5 months of each school year.
Retinal and Choroidal Folds in IIH and Papilledema
Invest Ophthalmol Vis Sci
Using fundus photos and optical coherence tomography, Sibony et al. examined the patterns, frequency, and biomechanical implications of retinal and choroidal folds in papilledema attributable to idiopathic intracranial hypertension (IIH).
The researchers surveyed fundus photos from 165 participants in the IIH Treatment Trial. Of these, 125 were also in the OCT Substudy Group and underwent spectral-domain optical coherence tomography (SD-OCT).
The researchers identified 3 types of folds among patients who had IIH with papilledema: peripapillary wrinkles (PPW), retinal folds (RF), and choroidal folds (CF). Fundus photos revealed the prevalence of these folds as 26%, 19%, and 1%, respectively. SD-OCT, however, detected a much higher prevalence: 46%, 47%, and 10%, respectively. These features may occur alone, or there may be more than 1 type within the same eye or between eyes.
Fundus photographs showed that among the 165 study eyes, 43 (26%) had PPW; 32 (19%) had RF, and 2 (1%) had CF. Overall, 68 eyes (41%) had at least 1 type of fold, and 7 (4%) had more than 1 type. The researchers noted that PPW were invariably located on the temporal half of the disc, and only 1 study eye had photographically visible folds on the nasal side. The most common location was just above the horizontal at 10 o’clock.
Retinal folds were most often found within the papillomacular bundle (63%) and were typically horizontal or slightly oblique. The researchers suggested that these folds resulted from the interplay between the degree of papilledema and the deformation of the sclera and the lamina cribrosa. The presence of retinal or choroidal folds did not appear to affect visual acuity or visual field in this study group.
Smartphone-Based Retinal Photography for Diabetic Retinopathy Screening
Rajalakshmi et al. evaluated the sensitivity and specificity of the “fundus on phone” (FOP) camera, a smartphone-based retinal imaging system developed in India, in screening for diabetic retinopathy (DR).
In this single-site, prospective, comparative, instrument-validation study, the researchers compared the new imaging system to standard 7-field digital retinal photography. They examined 301 patients (602 eyes) who had type 2 diabetes. Each patient underwent standard 7-field digital fundus photography with both a Carl Zeiss fundus camera and a FOP camera at a tertiary-care diabetes center in South India. The mean age of the study participants was 53.5 ± 9.6 years, and the mean duration of diabetes was 12.5 ± 7.3 years.
Two independent retina specialists evaluated the patients’ DR using the modified Early Treatment Diabetic Retinopathy Study (ETDRS) grading system. Sight-threatening DR was defined as the presence of proliferative DR or diabetic macular edema. The researchers assessed sensitivity, specificity, and image quality.
The Zeiss camera showed nonproliferative DR in 43.9% of the participants, and proliferative DR in 15.3%. By comparison, the FOP camera showed nonproliferative DR in 40.2%, and proliferative DR in 15.3%. The FOP’s sensitivity and specificity for detecting DR were 92.7% and 98.4%, respectively; the kappa (κ) agreement was 0.90. Compared with conventional fundus photography, the FOP’s sensitivity in detecting sight-threatening DR was 87.9%; specificity was 94.9%; and κ agreement, 0.80.
The researchers concluded that the combination of affordability, portability, and easy transmission of images would make the FOP useful both in the clinic and in mass DR screening programs in India and other low- and middle-income countries.
Roundup of Other Journals is written by Marianne Doran and edited by Deepak P. Edward, MD.
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