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1.
Ophthalmol Sci ; 2(4): 100208, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36531580

RESUMEN

Objective: To compare the rate of refractive growth (RRG3) of the crystalline lens ("lens") versus the eye excluding the lens ("globe") for the fellow, noncataractous eyes of participants in the Infant Aphakia Treatment Study. Design: Retrospective cohort study. Subjects: A total of 114 children who had unilateral cataract surgery as infants were recruited. Biometric and refraction data were obtained from the normal eyes at surgery and at 1, 5, and 10 years. Subjects were included if complete data (axial length [AL], corneal power, and refraction) were available at surgery and at 10 years of age. Methods: At surgery and at 1, 5, and 10 years, AL, corneal power, and cycloplegic refraction were measured in the normal eyes. For each eye, the RRG3 was defined by linear regression of refraction at the intraocular lens (IOL) plane against log10 (age + 0.6 years). The RRG3 for the globe was based on IOL power for emmetropia; the RRG3 for the lens was based on IOL power calculated to give the observed refractions. Intraocular lens powers were calculated with the Holladay 1 formula. The means were compared with a paired 2-tailed t test, and linear regression was used to look for a correlation between RRG3 of the lens globe. Main Outcome Measures: The RRG3 of the lens and globe. Results: Complete data were available for 107 normal eyes. The mean RRG3 of the lenses was -12.0 ± 2.5 diopters (D) and the mean RRG3 of the globes was -14.1 ± 2.7 D (P < 0.001). The RRG3 of the lens correlated with the RRG3 of the globe (R 2  = 0.25, P < 0.001). Conclusions: The RRG3 was 2 D more negative in globes compared with lenses in normal eyes. Globes with a greater rate of growth tended to have lenses with a greater rate of growth.

2.
J Cataract Refract Surg ; 47(2): 172-177, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-32925650

RESUMEN

PURPOSE: To report outcomes of secondary intraocular lens (IOL) implantation in the Infant Aphakia Treatment Study (IATS). SETTING: Multicenter clinical practice. DESIGN: Secondary analysis of patients enrolled in a randomized clinical trial. METHODS: Details regarding all secondary IOL surgeries conducted in children enrolled in the IATS were compiled. Visual outcomes, refractive outcomes, and adverse events at the age of 10½ years were evaluated. Comparisons were made with eyes that remained aphakic and with eyes randomized to primary IOL placement. RESULTS: The study included 114 infants, 57 in the aphakic group and 57 in the primary IOL group; 55 of 57 patients randomized to aphakia with contact lens correction were seen for the 10½-year study visit; 24 (44%) of 55 eyes had secondary IOL surgery. Median age at IOL surgery was 5.4 years (range 1.7 to 10.3 years). Mean absolute prediction error was 1.00 ± 0.70 diopters (D). At age 10½ years, the median logarithm of the minimum angle of resolution visual acuity (VA) was 0.9 (range 0.2 to 1.7), similar to VA in the 31 eyes still aphakic (0.8, range 0.1 to 2.9); the number of eyes with stable or improved VA scores between the 4½-year and 10½-year study visits was also similar (78% secondary IOL eyes; 84% aphakic eyes). For eyes undergoing IOL implantation after the 4½-year study visit (n = 22), the mean refraction at age 10½ years was -3.20 ± 2.70 D (range -9.90 to 1.10 D), compared with -5.50 ± 6.60 D (n = 53, range -26.50 to 3.00 D) in eyes with primary IOL (P = .03). CONCLUSIONS: Delayed IOL implantation allows a more predictable refractive outcome at age 10½ years, although the range of refractive error is still large.


Asunto(s)
Afaquia Poscatarata , Extracción de Catarata , Catarata , Lentes Intraoculares , Afaquia Poscatarata/cirugía , Niño , Preescolar , Estudios de Seguimiento , Humanos , Lactante , Implantación de Lentes Intraoculares , Complicaciones Posoperatorias , Estudios Retrospectivos
3.
J AAPOS ; 24(3): 134.e1-134.e6, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32461147

RESUMEN

PURPOSE: To determine the effect of age at penetrating keratoplasty (PKP) on graft survival and visual outcome in children with corneal opacities transplanted during infancy. METHODS: In this two-center retrospective consecutive cohort study, the medical records of infants who underwent unilateral or bilateral PKP during the first year of life between 2004 and 2011 were reviewed retrospectively. PKP was categorized as early (age 0-90 days) or late (age 91-365 days). Main outcome measures were graft survival and vision (classified as poor, fair, or good, considering both testing method and age norms). RESULTS: A total of 62 eyes of 52 infants were included: 19 eyes underwent early PKP; 43 eyes, late PKP. Of the 62 eyes, 61 had central congenital corneal opacities; 1 was acquired. Median follow-up was 38.1 months (range, 12.2-150.5 months). Kaplan-Meier graft survival estimates were 0.92 at 1 year (95% CI, 0.81-0.96) and 0.61 at 5 years (0.44-0.74). Graft survival (early PKP, 73.7%; late PKP, 65.1% [P = 0.57]) did not differ between groups. Of the 55 eyes with recorded visual acuities, no significant difference existed in proportion with ambulatory or better vision at latest follow-up between early and late PKP (42.1% vs 55.6%; P = 0.61). CONCLUSIONS: Visual outcomes were better for PKP performed during infancy compared to results of prior reports of late PKP; however, clearing of congenital opacities in the first 3 months of life did not improve visual outcomes compared to later PKP. One-half of grafts survived >5 years. Early PKP did not worsen graft survival, but PKP may be technically easier to perform later in infancy.


Asunto(s)
Enfermedades de la Córnea , Trasplante de Córnea , Estudios de Cohortes , Enfermedades de la Córnea/cirugía , Estudios de Seguimiento , Supervivencia de Injerto , Humanos , Lactante , Recién Nacido , Queratoplastia Penetrante , Estudios Retrospectivos , Resultado del Tratamiento
4.
Ophthalmology ; 127(9): 1259-1267, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32317177

RESUMEN

PURPOSE: The purpose of this assessment is to evaluate the accuracy of autorefraction compared with cycloplegic retinoscopy in children. METHODS: Literature searches were last conducted in October 2019 in the PubMed and the Cochrane Library databases for studies published in English. The combined searches yielded 118 citations, of which 53 were reviewed in full text. Of these, 31 articles were deemed appropriate for inclusion in this assessment and subsequently assigned a level of evidence rating by the panel methodologists. Four articles were rated level I, 11 were rated level II, and 16 were rated level III articles. The 16 level III articles were excluded from this review. RESULTS: Thirteen of the 15 studies comparing cycloplegic autorefraction with cycloplegic retinoscopy found a mean difference in spherical equivalent or sphere of less than 0.5 diopters (D); most were less than 0.25 D. Even lower mean differences were found when evaluating the cylindrical component of cycloplegic autorefraction versus cycloplegic retinoscopy. Despite low mean variability, there was significant individual measurement variability; the 95% limits of agreement were wide and included clinically relevant differences. Comparisons of noncycloplegic with cycloplegic autorefractions found that noncyloplegic refraction tends to over minus by 1 to 2 D. CONCLUSIONS: Cycloplegic autorefraction is appropriate to use in pediatric population-based studies. Cycloplegic retinoscopy can be valuable in individual clinical cases to confirm the accuracy of cycloplegic autorefraction, particularly when corrected visual acuity is worse than expected or the autorefraction results are not consistent with expected findings.


Asunto(s)
Oftalmología/organización & administración , Refracción Ocular/fisiología , Retinoscopía/normas , Evaluación de la Tecnología Biomédica , Academias e Institutos/organización & administración , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Midriáticos/administración & dosificación , Reproducibilidad de los Resultados , Estados Unidos
5.
Ophthalmology ; 126(1): 146-155, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30075202

RESUMEN

PURPOSE: To review the published literature assessing the efficacy of ß-blockers for the treatment of periocular hemangioma in infants. METHODS: Literature searches were conducted in May 2018 in PubMed with no date restrictions and limited to studies published in English and in the Cochrane Library database without any restrictions. The combined searches yielded 437 citations. Of these,16 articles were deemed appropriate for inclusion in this assessment and assigned a level of evidence rating by the panel methodologist. RESULTS: None of the 16 studies included in this assessment were rated level I, 3 were rated level II, and 13 were rated level III. The most common treatment regimen was 2 mg/kg daily oral propranolol, but intralesional and topical ß-blockers were also used. Treatment effect was most often measured in terms of reduction in the size of the lesions, which occurred in the majority of patients. ß-Blockers were consistently shown to reduce astigmatism, but this reduction was shown to be statistically significant in only 2 series. The effect of ß-blockers on amblyopia was not adequately documented. ß-Blockers were generally well tolerated and had mild side effects (fatigue, gastrointestinal upset/diarrhea, restlessness/sleep disturbances, minor wheezing, and cold extremities). Complications severe enough to require cessation of treatment occurred in only 2 patients out of a total of 229 who received ß-blockers. CONCLUSIONS: There is limited evidence to support the safety and efficacy of both topical and systemic ß-blockers to promote regression of periocular hemangiomas. Additional research may confirm the best dosage and route of administration to maximize efficacy in reducing induced astigmatism and amblyopia associated with periocular hemangiomas while minimizing side effects.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Neoplasias de los Párpados/tratamiento farmacológico , Hemangioma Capilar/tratamiento farmacológico , Neoplasias Orbitales/tratamiento farmacológico , Propranolol/uso terapéutico , Academias e Institutos/organización & administración , Antagonistas Adrenérgicos beta/efectos adversos , Preescolar , Neoplasias de los Párpados/patología , Hemangioma Capilar/patología , Humanos , Lactante , Recién Nacido , Oftalmología/organización & administración , Neoplasias Orbitales/patología , Propranolol/efectos adversos , Evaluación de la Tecnología Biomédica , Resultado del Tratamiento
6.
Ophthalmology ; 126(4): 623-636, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30476518

RESUMEN

PURPOSE: To review the published evidence to evaluate the ability of orthokeratology (Ortho-K) treatment to reduce myopic progression in children and adolescents compared with the use of spectacles or daytime contact lenses for standard refractive correction. METHODS: Literature searches of the PubMed database, the Cochrane Library, and the databases of clinical trials were last conducted on August 21, 2018, with no date restrictions but limited to articles published in English. These searches yielded 162 citations, of which 13 were deemed clinically relevant for full-text review and inclusion in this assessment. The panel methodologist then assigned a level of evidence rating to the selected studies. RESULTS: The 13 articles selected for inclusion include 3 prospective, randomized clinical trials; 7 nonrandomized, prospective comparative studies; and 3 retrospective case series. One study provided level I evidence, 11 studies provided level II evidence, and 1 study provided level III evidence. Most studies were performed in populations of Asian ethnicity. Change in axial length was the primary outcome for 10 of 13 studies and change in refraction was the primary outcome for 3 of 13 studies. In these studies, Ortho-K typically reduced axial elongation by approximately 50% over a 2-year study period. This corresponds to average axial length change values of approximately 0.3 mm for Ortho-K patients compared with 0.6 mm for control patients, which corresponds to a typical difference in refraction of approximately 0.5 diopters (D). Younger age groups and individuals with larger than average pupil size may have a greater effect with Ortho-K. Rebound can occur after discontinuation or change to alternative refractive treatment. CONCLUSIONS: Orthokeratology may be effective in slowing myopic progression for children and adolescents, with a potentially greater effect when initiated at an early age (6-8 years). Safety remains a concern because of the risk of potentially blinding microbial keratitis from contact lens wear.


Asunto(s)
Miopía/prevención & control , Procedimientos de Ortoqueratología , Academias e Institutos/organización & administración , Niño , Bases de Datos Factuales , Progresión de la Enfermedad , Humanos , Miopía/diagnóstico , Evaluación de la Tecnología Biomédica , Resultado del Tratamiento , Estados Unidos
7.
Ophthalmology ; 125(9): 1452-1458, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29631901

RESUMEN

PURPOSE: To review the published literature to assess the visual outcomes and adverse events associated with the 2 most commonly used contact lenses for treating aphakia in children: silicone elastomer (SE) and rigid gas permeable (RGP). METHODS: Literature searches were last conducted in January 2018 in the PubMed, Cochrane Library, and ClinicalTrials.gov databases with no date or language restrictions. These combined searches yielded 167 citations, 27 of which were reviewed in full text. Of these, 10 articles were deemed appropriate for inclusion in this assessment and subsequently assigned a level of evidence rating by the panel methodologist. RESULTS: The literature search identified 4 level II studies and 6 level III studies. There were insufficient data to compare visual outcomes for eyes treated using SE lenses versus RGP lenses. Silicone elastomer lenses have the advantage that they can be worn on an extended-wear basis, but they were associated with more adverse events than RGP lenses. These adverse events included microbial keratitis, corneal infiltrates, corneal edema, corneal scars, lenses adhering to the cornea, superficial punctate keratopathy, lid swelling, and conjunctival hyperemia. The lens replacement rate was approximately 50% higher for RGP lenses in the only study that directly compared SE and RGP lenses. CONCLUSIONS: Limited evidence was found in the literature on this topic. Silicone elastomer and RGP contact lenses were found to be effective for treating aphakia in children. Silicone elastomer lenses are easier to fit and may be worn on an extended-wear basis. Rigid gas permeable lenses must be removed every night and require a more customized fit, but they are associated with fewer adverse events. The choice of which lens a practitioner prescribes should be based on the particular needs of each patient.


Asunto(s)
Academias e Institutos , Afaquia/terapia , Lentes de Contacto , Oftalmología , Niño , Humanos , Estados Unidos
8.
Ophthalmology ; 124(12): 1857-1866, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28669492

RESUMEN

PURPOSE: To review the published literature on the efficacy of topical atropine for the prevention of myopic progression in children. METHODS: Literature searches were last conducted in December 2016 in the PubMed database with no date restrictions, but were limited to studies published in English, and in the Cochrane Library database without any restrictions. The combined searches yielded 98 citations, 23 of which were reviewed in full text. Of these, 17 articles were deemed appropriate for inclusion in this assessment and subsequently were assigned a level of evidence rating by the panel methodologist. RESULTS: Seventeen level I, II, and III studies were identified. Most of the studies reported less myopic progression in children treated with atropine compared with various control groups. All 8 of the level I and II studies that evaluated primarily myopic progression revealed less myopic progression with atropine (myopic progression ranging from 0.04±0.63 to 0.47±0.91 diopters (D)/year) compared with control participants (myopic progression ranging from 0.38±0.39 to 1.19±2.48 D/year). In studies that evaluated myopic progression after cessation of treatment, a rebound effect was noted. Several studies evaluated the optimal dosage of atropine with regard to myopic progression, rebound after treatment cessation, and minimization of side effects. Lower dosages of atropine (0.5%, 0.1%, and 0.01%) were found to be slightly less effective during treatment periods of 1 to 2 years, but they were associated with less rebound myopic progression (for atropine 0.01%, mean myopic progression after treatment cessation of 0.28±0.33 D/year, compared with atropine 0.5%, 0.87±0.52 D/year), fewer side effects, and similar long-term results for myopic progression after the study period and rebound effect were considered. The most robust and well-designed studies were carried out in Asian populations. Studies involving patients of other ethnic backgrounds failed to provide sufficient evidence of an effect of atropine on myopic progression. CONCLUSIONS: Level I evidence supports the use of atropine to prevent myopic progression. Although there are reports of myopic rebound after treatment is discontinued, this seems to be minimized by using low doses (especially atropine 0.01%).


Asunto(s)
Atropina/uso terapéutico , Midriáticos/uso terapéutico , Miopía/prevención & control , Academias e Institutos/organización & administración , Niño , Preescolar , Bases de Datos Factuales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Miopía/diagnóstico , Oftalmología/organización & administración , Evaluación de la Tecnología Biomédica , Resultado del Tratamiento , Estados Unidos
9.
Ophthalmology ; 124(5): 619-633, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28341474

RESUMEN

PURPOSE: To review the available evidence on the ocular safety and efficacy of anti-vascular endothelial growth factor (VEGF) agents for the treatment of retinopathy of prematurity (ROP) compared with laser photocoagulation therapy. METHODS: A literature search of the PubMed and Cochrane Library databases was conducted last on September 6, 2016, with no date restrictions and limited to articles published in English. This search yielded 311 citations, of which 37 were deemed clinically relevant for full-text review. Thirteen of these were selected for inclusion in this assessment. The panel methodologist assigned ratings to the selected articles according to the level of evidence. RESULTS: Of the 13 citations, 6 articles on 5 randomized clinical trials provided level II evidence supporting the use of anti-VEGF agents, either as monotherapy or in combination with laser therapy. The primary outcome for these articles included recurrence of ROP and the need for retreatment (3 articles), retinal structure (2 articles), and refractive outcome (1 article). Seven articles were comparative case series that provided level III evidence. The primary outcomes included the effects of anti-VEGF treatment on development of peripheral retinal vessels (1 article), refractive outcomes (1 article), or both structural and refractive or visual outcomes (5 articles). CONCLUSIONS: Current level II and III evidence indicates that intravitreal anti-VEGF therapy is as effective as laser photocoagulation for achieving regression of acute ROP. Although there are distinct ocular advantages to anti-VEGF pharmacotherapy for some cases (such as eyes with zone I disease or aggressive posterior ROP), the disadvantages are that the ROP recurrence rate is higher, and vigilant and extended follow-up is needed because retinal vascularization is usually incomplete. After intravitreal injection, bevacizumab can be detected in serum within 1 day, and serum VEGF levels are suppressed for at least 8 to 12 weeks. The effects of lowering systemic VEGF levels on the developing organ systems of premature infants are unknown, and there are limited long-term data on potential systemic and neurodevelopmental effects after anti-VEGF use for ROP treatment. Anti-VEGF agents should be used judiciously and with awareness of the known and unknown or potential side effects.


Asunto(s)
Academias e Institutos , Inhibidores de la Angiogénesis/administración & dosificación , Oftalmología , Retinopatía de la Prematuridad/tratamiento farmacológico , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Humanos , Inyecciones Intravítreas , Estados Unidos
11.
Ophthalmology ; 123(4): 804-16, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26832657

RESUMEN

OBJECTIVE: To assess the accuracy with which available retinopathy of prematurity (ROP) predictive models detect clinically significant ROP and to what extent and at what risk these models allow for the reduction of screening examinations for ROP. METHODS: A literature search of the PubMed and Cochrane Library databases was conducted last on May 1, 2015, and yielded 305 citations. After screening the abstracts of all 305 citations and reviewing the full text of 30 potentially eligible articles, the panel members determined that 22 met the inclusion criteria. One article included 2 studies, for a total of 23 studies reviewed. The panel extracted information about study design, study population, the screening algorithm tested, interventions, outcomes, and study quality. The methodologist divided the studies into 2 categories-model development and model validation-and assigned a level of evidence rating to each study. One study was rated level I evidence, 3 studies were rated level II evidence, and 19 studies were rated level III evidence. RESULTS: In some cohorts, some models would have allowed reductions in the number of infants screened for ROP without failing to identify infants requiring treatment. However, the small sample size and limited generalizability of the ROP predictive models included in this review preclude their widespread use to make all-or-none decisions about whether to screen individual infants for ROP. As an alternative, some studies proposed approaches to apply the models to reduce the number of examinations performed in low-risk infants. CONCLUSIONS: Additional research is needed to optimize ROP predictive model development, validation, and application before such models can be used widely to reduce the burdensome number of ROP screening examinations.


Asunto(s)
Algoritmos , Técnicas de Diagnóstico Oftalmológico , Modelos Biológicos , Oftalmología/organización & administración , Retinopatía de la Prematuridad/diagnóstico , Evaluación de la Tecnología Biomédica/organización & administración , Academias e Institutos/organización & administración , Bases de Datos Factuales , Edad Gestacional , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Reproducibilidad de los Resultados , Estados Unidos
12.
JAMA Ophthalmol ; 132(7): 823-31, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24676353

RESUMEN

IMPORTANCE: While older children and adults with achromatopsia have been studied, less is known of young children with achromatopsia. OBJECTIVES: To characterize the macular and foveal architecture of patients with achromatopsia during early childhood with handheld spectral-domain optical coherence tomographic imaging and to make phenotype-genotype correlations. DESIGN, SETTING, AND PARTICIPANTS: Comparative case series of 9 patients with achromatopsia and 9 age-matched control participants at a tertiary ophthalmology referral center. MAIN OUTCOMES AND MEASURES: Patients underwent complete ocular examination, full-field electroretinography, handheld spectral-domain optical coherence tomographic imaging, and screening for genetic mutations. RESULTS: The mean (SD) age of the patients with achromatopsia was 4.2 (2.4) years, and the mean (SD) age of the control participants was 4.0 (2.1) years. Cone-driven responses to photopic single-flash or 30-Hz stimuli were nonrecordable in 7 patients and severely attenuated in 2. Rod-driven responses to dim scotopic single-flash stimuli were normal in 7 patients and mildly subnormal in 2. Six patients (67%) had foveal ellipsoid zone disruption, of which 1 had a hyporeflective zone. Four patients (44%) had foveal hypoplasia. The average total retinal thicknesses of the macula and fovea in the patients with achromatopsia were 14% and 17% thinner than in the control participants (P < .001 and P = .001), which was mostly due to the outer retina that was 18% and 26% thinner than in control participants (both P < .001), respectively. Genetic testing revealed a common homozygous mutation in CNGB3 in 5 patients with complete achromatopsia and heterozygous mutations in CNGA3 in 2 patients with incomplete achromatopsia. The youngest and worst-affected patient harbored compound heterozygous mutations in CNGB3 and a single mutation in CNGA3. CONCLUSIONS AND RELEVANCE: In early childhood, there is a spectrum of foveal pathology that is milder than reported in older individuals with achromatopsia, which suggests the need for early therapeutic intervention. Neither age alone nor genotype alone predicts the degree of photoreceptor loss or preservation. Thus, in anticipation of future gene therapy trials in humans, we propose that handheld spectral-domain optical coherence tomography is an important tool for the early assessment and stratification of macular architecture in young children with achromatopsia.


Asunto(s)
Defectos de la Visión Cromática/diagnóstico , Terapia Genética , Retina/patología , Enfermedades de la Retina/diagnóstico , Niño , Preescolar , Defectos de la Visión Cromática/genética , Defectos de la Visión Cromática/terapia , Canales Catiónicos Regulados por Nucleótidos Cíclicos/genética , Análisis Mutacional de ADN , Adaptación a la Oscuridad , Electrorretinografía , Femenino , Mutación del Sistema de Lectura , Estudios de Asociación Genética , Humanos , Lactante , Masculino , Nistagmo Patológico/diagnóstico , Fotofobia/diagnóstico , Errores de Refracción/diagnóstico , Enfermedades de la Retina/genética , Enfermedades de la Retina/terapia , Tomografía de Coherencia Óptica , Agudeza Visual/fisiología
13.
J AAPOS ; 15(6): 609-11, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22153413

RESUMEN

We report a case of extensive bilateral intraretinal hemorrhages in a premature infant with active retinopathy of prematurity (ROP) after an examination with scleral depression. In the only other previously reported case, the retinal hemorrhages were limited to the posterior pole of an eye with preexisting vitreous hemorrhage, and the child had a history of severe necrotizing enterocolitis that required surgery. Investigators have hypothesized that the combination of ocular manipulation, abrupt intraocular pressure change, and fragile immature retinal vasculature with poor autoregulation may contribute to the pathogenesis of retinal hemorrhages. Physicians performing ROP examinations should be aware of this possibility and judiciously use scleral depression; however, examination-induced retinal hemorrhages in children have never been reported in the absence of active ROP.


Asunto(s)
Técnicas de Diagnóstico Oftalmológico/efectos adversos , Hemorragia Retiniana/etiología , Retinopatía de la Prematuridad/diagnóstico , Esclerótica , Femenino , Humanos , Lactante , Recién Nacido , Presión/efectos adversos
14.
Invest Ophthalmol Vis Sci ; 47(10): 4277-87, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17003416

RESUMEN

PURPOSE: Motivated by pharmacologic findings linking nicotinic acetylcholine receptors to eye development in chicks, the authors studied whether the refractions of children who were passively exposed to cigarette smoke by their parents differed from those of nonexposed children. METHODS: A cross-sectional study was conducted among 323 patients (mean +/- SD age, 8.7 +/- 4.4 years; range, 1-20) in a tertiary care pediatric ophthalmology clinic. Half (162/323) of the subjects had strabismus. The accompanying parent completed a detailed questionnaire on parental smoking history and on putative risk factors for myopia. The results were compared to the subjects' cycloplegic refractions. RESULTS: If one or both parents ever smoked, their children had a lower myopia prevalence (12.4% vs. 25.4%; P = 0.004) and more hyperopic mean refractions (1.83 +/- 0.24 vs. 0.96 +/- 0.27 diopters; P = 0.02) than those whose parents never smoked. Smoking by either parent during the mother's pregnancy had a similar effect on the child's refraction. The associations largely persisted, both in multivariate models that included adjustments for the child's age, child's body mass index, child's nearwork activity, parental myopia, and parental education and also in analysis by subgroups stratified by strabismus status. CONCLUSIONS: Despite the complex constituents of cigarette smoke, neuropharmacology perspectives may prove useful in the development of new hypotheses to understand the mechanisms governing refractive development, not only in experimental animals but also in children. The associations of less prevalent myopia and a more hyperopic mean refraction with both prenatal and childhood exposures to tobacco smoke suggest that nongenetic, environmental exposures may have long-term influences on refraction and that further study of the role of nicotinic acetylcholine receptors in refractive development is warranted.


Asunto(s)
Padres , Refracción Ocular , Errores de Refracción/etiología , Contaminación por Humo de Tabaco/efectos adversos , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Delaware/epidemiología , Femenino , Humanos , Lactante , Masculino , New Jersey/epidemiología , Pennsylvania/epidemiología , Errores de Refracción/epidemiología , Factores de Riesgo , Encuestas y Cuestionarios
15.
Invest Ophthalmol Vis Sci ; 47(5): 1778-84, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16638981

RESUMEN

PURPOSE: To determine in human eyes whether diurnal fluctuations in axial length are related to fluctuations in intraocular pressure (IOP) by studying these fluctuations in both eyes of individual subjects and by assessing the regularity of both rhythms on two separate study days. METHODS: Ten subjects, ages 18 to 24 years, underwent serial axial length and IOP measurements using highly precise, noncontact partial coherence interferometry and Goldmann applanation tonometry, respectively. Both eyes were measured at six 3-hour intervals during each of two study days, and significant fluctuations were modeled by sine curves. RESULTS: Of the 40 data sets, 29 had significant axial length high-low differences and 32 had significant IOP high-low differences (ANOVA, P < 0.05 for each). The magnitude of the significant high-low differences were 38 +/- 22 microm for axial length and 6.0 +/- 1.9 mm Hg for IOP (mean +/- SD). Neither axial length nor IOP fluctuations necessarily occurred bilaterally on the same day, and neither rhythm was regularly observed on two separate days in individual eyes. In eyes in which both parameters fluctuated on the same day, there were no correlations in the amplitude, period or phase of the two rhythms. CONCLUSIONS: Both axial length and IOP fluctuate during the day much of the time in most subjects. However, diurnal IOP fluctuations do not appear to cause diurnal axial length fluctuations.


Asunto(s)
Ritmo Circadiano/fisiología , Ojo/anatomía & histología , Presión Intraocular/fisiología , Adolescente , Adulto , Pesos y Medidas Corporales , Humanos , Interferometría , Luz , Tonometría Ocular
16.
J Biomed Mater Res A ; 68(4): 756-62, 2004 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-14986330

RESUMEN

Collagen is commonly used as a tissue-engineering scaffold, yet its in vivo applications are limited by a deficiency in mechanical strength. The purpose of this work was to explore the utilization of a unique enzymatic crosslinking procedure aimed at improving the mechanical properties of collagen-based scaffold materials. Type I bovine collagen gel was crosslinked by transglutaminase, which selectively mediates the chemical reaction between glutamine and lysine residues on adjacent protein fibers, thus providing covalent amide bonds that serve to reinforce the three-dimensional matrix. The degree of crosslinking was verified by thermal analysis and amine group content. The denaturation temperature of crosslinked collagen reached a maximum of 66 +/- 1 degrees C. The chemical reaction was confirmed to be noncytotoxic with respect to bone marrow stromal cells acquired from New Zealand White rabbits. Tube-shaped cellular constructs fashioned from crosslinked collagen and bone marrow stromal cells were found to have burst pressures significantly higher than their noncrosslinked analogs (71 +/- 4 mmHg vs. 46 +/- 3 mmHg; p < 0.01). Thus, the transglutaminase mediated reaction served to successfully strengthen collagen gels while remaining benign toward cells.


Asunto(s)
Colágeno/metabolismo , Reactivos de Enlaces Cruzados/metabolismo , Hidrogeles/síntesis química , Transglutaminasas/metabolismo
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