RESUMEN
Down syndrome (DS) is the most common chromosomal disorder in humans. DS is associated with increased prevalence of several ocular sequelae, including characteristic blue-dot cerulean cataract. DS is accompanied by age-dependent accumulation of Alzheimer's disease (AD) amyloid-ß (Aß) peptides and amyloid pathology in the brain and comorbid early-onset Aß amyloidopathy and colocalizing cataracts in the lens. Quasi-elastic light scattering (QLS) is an established optical technique that noninvasively measures changes in protein size distributions in the human lens in vivo. In this cross-sectional study, lenticular QLS correlation time was decreased in adolescent subjects with DS compared to age-matched control subjects. Clinical QLS was consistent with alterations in relative particle hydrodynamic radius in lenses of adolescents with DS. These correlative results suggest that noninvasive QLS can be used to evaluate molecular changes in the lenses of individuals with DS.
Asunto(s)
Enfermedad de Alzheimer , Catarata/congénito , Síndrome de Down , Cristalino , Humanos , Adolescente , Síndrome de Down/complicaciones , Síndrome de Down/patología , Estudios Transversales , Enfermedad de Alzheimer/metabolismo , Cristalino/metabolismo , Péptidos beta-Amiloides/metabolismoRESUMEN
Down syndrome is the most common genetically mediated intellectual disability. Although many physiologic and pathologic features of Down syndrome are discussed at length in the literature, the ocular manifestations of Down syndrome have seldom been discussed in a comprehensive fashion. Given that Down syndrome has ocular manifestations from the front to the back of the eye, it is important for physicians to become familiar with these manifestations, especially given the prevalence of Down syndrome. This review aims to discuss the varied ophthalmologic manifestations of Down syndrome - including strabismus, amblyopia, nystagmus, accommodation deficits, nasolacrimal duct obstruction, keratoconus, optic nerve pathology, neoplastic disease, and retinal pathology - to facilitate better care and visual outcomes in this important patient population.
RESUMEN
The absence of clinical tools to evaluate individual variation in the pace of aging represents a major impediment to understanding aging and maximizing health throughout life. The human lens is an ideal tissue for quantitative assessment of molecular aging in vivo. Long-lived proteins in lens fiber cells are expressed during fetal life, do not undergo turnover, accumulate molecular alterations throughout life, and are optically accessible in vivo. We used quasi-elastic light scattering (QLS) to measure age-dependent signals in lenses of healthy human subjects. Age-dependent QLS signal changes detected in vivo recapitulated time-dependent changes in hydrodynamic radius, protein polydispersity, and supramolecular order of human lens proteins during long-term incubation (~1 year) and in response to sustained oxidation (~2.5 months) in vitro. Our findings demonstrate that QLS analysis of human lens proteins provides a practical technique for noninvasive assessment of molecular aging in vivo.
Asunto(s)
Envejecimiento/fisiología , Cristalinas/fisiología , Dispersión Dinámica de Luz , Cristalino/fisiología , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Cristalinas/química , Dispersión Dinámica de Luz/métodos , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Masculino , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Oxidación-Reducción , Adulto JovenRESUMEN
PURPOSE: Assessment of visual outcome of pediatric eyes that underwent cataract extraction with primary intraocular lens (IOL) implantation at a single center. METHODS: A retrospective review of charts of 510 consecutive pediatric patients that underwent cataract extraction was performed. Exclusion criteria were traumatic cataract, secondary IOL implantation, retinopathy of prematurity, severe developmental delay, age less than 4 years at last follow-up, and follow-up less than 6 months. In bilateral cases, only right eye data were included. RESULTS: One hundred thirty-nine eyes met inclusion criteria. Median age at surgery was 5.12 years (range, 0.03-16.92); median age at last follow-up was 9.05 years, and median follow-up was 3.65 years. Sixty-six of 139 (47.5%) patients had unilateral cataracts compared with 73/139 (52.5%) bilateral cases. The median visual acuity of all eyes was 20/30, with median visual acuity of unilateral and bilateral cases being 20/40 and 20/25, respectively. Older patients achieved better visual acuity (unilateral cases: p = 0.003; bilateral cases: p = 0.07). Eyes with a greater interocular axial length difference achieved poorer visual acuity. Forty-five patients had a final visual acuity worse than 20/40. Of these, 34 (76%) had a diagnosis of amblyopia as the sole cause. Nineteen of 139 (13.7%) eyes had final visual acuity worse than 20/200. Eighteen patients required strabismus surgery, and 22 required additional intraocular surgery. CONCLUSIONS: Better visual acuity was associated with bilateral cataract, older age at surgery, and normal interocular axial length difference. Amblyopia was the major cause of residual visual deficit.