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Citation: Moura ALA, Nagy BV, La Morgia C, et al. The pupil light reflex in Leber's hereditary optic neuropathy: evidence for preservation of melanopsin-expressing retinal ganglion cells. Invest Ophthalmol Vis Sci. 2013;54:4471-4477. DOI: 10.1167/iovs.12-11137 PURPOSE. To investigate the pupillary light reflex (PLR) of patients with severe loss of vision due to Leber's Hereditary Optic Neuropathy (LHON) in the context of a proposed preservation of melanopsin-expressing retinal ganglion cells (mRGCs). METHODS.Ten LHON patients (7 males; 51.6 6 14.1 years), with visual acuities ranging from 20/400 to hand motion perception and severe visual field losses, were tested and compared with 16 healthy subjects (7 males; 42.15 6 15.4 years) tested as controls. PLR was measured with an eye tracker and the stimuli were controlled with a Ganzfeld system. Pupil responses were measured monocularly, to 1 second of blue (470 nm) and red (640 nm) flashes with 1, 10, 100, and 250 cd/m 2 luminances. The normalized amplitude of peak of the transient PLR and the amplitude of the sustained PLR at 6 seconds after the flash offset were measured. In addition, optical coherence topography (OCT) scans of the peripapillary retinal nerve fiber layer were obtained.RESULTS. The patient's peak PLR responses were on average 15% smaller than controls (P < 0.05), but 5 out of 10 patients had amplitudes within the range of controls. The patients' sustained PLRs were comparable with controls at lower flash intensities, but on average, 27% smaller to the 250 cd/m 2 blue light, although there was considerable overlap with the PLR amplitudes of control. All patients had severe visual field losses and the retinal nerve fiber layer thickness was reduced to a minimum around the optic disc in 8 of the 10 patients.CONCLUSIONS. The PLR is maintained overall in LHON patients despite the severity of optic atrophy. These results are consistent with previous evidence of selective preservation of mRGCs.

Vision impairment is a significant problem in older Brazilians reinforcing the need to implement prevention of blindness programs for elderly people with emphasis on those without schooling.

Purpose To report the findings of a cross-sectional study of visual function in infants with confirmed or suspected antenatal Zika virus (ZIKV) infection seen at a single referral center in Rio de Janeiro. Methods Infants were examined following the ZIKV outbreak period at Fernandes Figueira Institute/FIOCRUZ. Visual function was considered abnormal if an infant could not fix and follow a standardized high-contrast target (10 cm) by 3–6 months of age. Visual function and associations with structural eye abnormalities, central nervous system (CNS) abnormalities, microcephaly, and nystagmus were assessed. Sensitivity and specificity of screening criteria for structural eye abnormalities was assessed. Results A total of 173 infants met inclusion criteria. Reduced visual function was found in 52 infants (30.0%) and was significantly associated with eye abnormalities (40/52; OR = 44.2; 95% CI, 16.6–117.6), CNS abnormalities (50/52; OR = 64.0; 95% CI, 14.7–277.6), microcephaly (44/52; OR = 31.5; 95% CI,12.7–77.8), and nystagmus (26/52; OR = 120.0; 95% CI, 15.6–924.5). Using microcephaly as screening criteria for the detection of eye abnormalities provided a sensitivity of 88.9% (95% CI,76.0–96.3) and specificity of 82.8% (95% CI, 75.1–88.9). Using both abnormal visual function and microcephaly increased sensitivity to 100% (95% CI, 92.1–100.0) and decreased specificity to 80.5% (95% CI, 72.5–86.9). Conclusions Infants with suspected antenatal ZIKV infection and reduced visual function should be referred to an ophthalmologist. Visual function assessments are helpful in screening for antenatal ZIKV exposure in resource-limited settings and can identify infants who may benefit from visual habilitation.

Our purpose is to provide a summary overview of blindness and visual impairment on the context of recent Brazilian ocular epidemiologic studies. Synthesis of data from two cross-sectional population-based studies -the São Paulo Eye Study and the Refractive Error in School Children Study is presented. 3678 older adults and 2441 school children were examined between July 2004 and December 2005. Prevalence of blindness in older adults using presenting visual acuity was 1.51% decreasing to 1.07% with refractive correction. The most common causes of blindness in older adults were retinal disorders, followed by cataract and glaucoma. In school children, the prevalence of uncorrected visual impairment was 4.82% decreasing to 0.41% with refractive correction. The most common cause of visual impairment in school children was uncorrected refractive error. Visual impairment and blindness in Brazil is an important public health problem. It is a significant problem in older Brazilians, reinforcing the need to implement prevention of blindness programs for elderly people with emphasis on those without schooling. In school-children cost-effective strategies are needed to address a readily treatable cause of vision impairment -prescription and provision of glasses.

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PURPOSE To investigate the prevalence and visual acuity (VA) outcomes of cataract surgery in a low- to middle-income population in São Paulo, Brazil. DESIGN Population-based, cross-sectional study. METHODS Cluster sampling was used in randomly selecting those ≥50 years old for VA measurement, refraction, and ocular examination. Participants were queried as to the year and type of facility for previous cataract surgery. Surgical procedure and evidence of surgical complications were noted. Main outcome measures were presenting and best-corrected vision, and the principal cause for eyes presenting with VA ≤20/40. RESULTS A total of 4,224 eligible persons were enumerated and 3,678 (87.1%) were examined. The prevalence of cataract surgery was 6.28% (95% confidence interval [CI], 5.29% to 7.27%). Surgical coverage for presenting VA <20/63 in both eyes because of cataract was 61.4%. Unoperated cataract impairment/blindness was associated with older age and lack of schooling. Among the 352 cataract-operated eyes, 41.2% presented with VA >20/40, 28.1% with VA 20/40 to 20/63, 14.2% with VA <20/63 to 20/200, and 16.5% with VA <20/200. With best correction, the percentages were 61.9%, 17.6%, 8.2%, and 12.2%. Intraocular lenses were found in 90.6% of cataract-operated eyes; half appeared to have been operated by phacoemulsification. Refractive error and retinal disorders were the main cause of vision impairment/blindness in operated eyes. CONCLUSIONS Cataract surgery has increased in São Paulo, but many remain visually impaired/blind because of cataract. Refractive error and other causes of impairment are common in cataract-operated eyes. Emphasis on the quality of VA outcomes and sustained government subsidy to provide access to affordable modern cataract surgery are needed.