951 resultados para Objective visual acuity
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Background. Over 39.9% of the adult population forty or older in the United States has refractive error, little is known about the etiology of this condition and associated risk factors and their entailed mechanism due to the paucity of data regarding the changes of refractive error for the adult population over time.^ Aim. To evaluate risk factors over a long term, 5-year period, in refractive error changes among persons 43 or older by testing the hypothesis that age, gender, systemic diseases, nuclear sclerosis and baseline refractive errors are all significantly associated with refractive errors changes in patients at a Dallas, Texas private optometric office.^ Methods. A retrospective chart review of subjective refraction, eye health, and self-report health history was done on patients at a private optometric office who were 43 or older in 2000 who had eye examinations both in 2000 and 2005. Aphakic and pseudophakic eyes were excluded as well as eyes with best corrected Snellen visual acuity of 20/40 and worse. After exclusions, refraction was obtained on 114 right eyes and 114 left eyes. Spherical equivalent (sum of sphere + ½ cylinder) was used as the measure of refractive error.^ Results. Similar changes in refractive error were observed for the two eyes. The 5-year change in spherical power was in a hyperopic direction for younger age groups and in a myopic direction for older subjects, P<0.0001. The gender-adjusted mean change in refractive error in right eyes of persons aged 43 to 54, 55 to 64, 65 to 74, and 75 or older at baseline was +0.43D, +0.46 D, -0.09 D, and -0.23D, respectively. Refractive change was strongly related to baseline nuclear cataract severity; grades 4 to 5 were associated with a myopic shift (-0.38 D, P< 0.0001). The mean age-adjusted change in refraction was +0.27 D for hyperopic eyes, +0.56 D for emmetropic eyes, and +0.26 D for myopic eyes.^ Conclusions. This report has documented refractive error changes in an older population and confirmed reported trends of a hyperopic shift before age 65 and a myopic shift thereafter associated with the development of nuclear cataract.^
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Although more than 100 genes associated with inherited retinal disease have been mapped to chromosomal locations, less than half of these genes have been cloned. This text includes identification and evaluation of candidate genes for three autosomal dominant forms of inherited retinal degeneration: atypical vitelliform macular dystrophy (VMD1), cone-rod dystrophy (CORD), and retinitis pigmentosa (RP). ^ VMD1 is a disorder characterized by complete penetrance but extremely variable expressivity, and includes macular or peripheral retinal lesions and peripappilary abnormalitites. In 1984, linkage was reported between VMD1 and soluble glutamate-pyruvate transaminase GPT); however, placement of GPT to 8q24 on linkage maps had been debated, and VMD1 did not show linkage to microsatellite markers in that region. This study excluded linkage between the loci by cloning GPT, identifying the nucleotide substitution associated with the GPT sozymes, and by assaying VMD1 family samples with an RFLP designed to detect the substitution. In addition, linkage of VMD1 to the known dominant macular degeneration loci was excluded. ^ CORD is characterized by early onset of color-vision deficiency, and decreased visual acuity, However, this retinal degeneration progresses to no light perception, severe macular lesion, and “bone-spicule” accumulations in the peripheral retina. In this study, the disorder in a large Texan family was mapped to the CORD2 locus of 19q13, and a mutation in the retina/pineal-specific cone-rod homeobox gene (CRX) was identified as the disease cause. In addition, mutations in CRX were associated with significantly different retinal disease phenotypes, including retinitis pigmentosa and Leber congenital amaurosis. ^ Many of the mutations leading to inherited retinal disorders have been identified in genes like CRX, which are expressed predominantly in the retina and pineal gland. Therefore, a combination of database analysis and laboratory investigation was used to identify 26 novel retina/pineal-specific expressed sequence tag (EST) clusters as candidate genes for inherited retinal disorders. Eight of these genes were mapped into the candidate regions of inherited retinal degeneration loci. ^ Two of the eight clusters mapped into the retinitis pigmentosa RP13 candidate region of 17p13, and were both determined to represent a single gene that is highly expressed in photoreceptors. This gene, the Ah receptor-interacting like protein-1 (AIPL1), was cloned, characterized, and screened for mutations in RP13 patient DNA samples. ^
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PURPOSE To evaluate the effect of the vitreomacular interface (VMI) on treatment efficacy of intravitreal therapy in uveitic cystoid macular oedema (CME). METHODS Retrospective analysis of CME resolution, CME recurrence rate and monthly course of central retinal thickness (CRT), retinal volume (RV) and best corrected visual acuity (BCVA) after intravitreal injection with respect to the VMI configuration on spectral-domain OCT using chi-squared test and repeated measures anova adjusted for confounding covariates epiretinal membrane, administered drug and subretinal fluid. RESULTS Fifty-nine eyes of 53 patients (mean age: 47.4 ± 16.9 years) were included. VMI status had no effect on complete CME resolution rate (p = 0.16, corrected p-value: 0.32), time until resolution (p = 0.09, corrected p-value: 0.27) or CME relapse rate (p = 0.29, corrected p-value: 0.29). Change over time did not differ among the VMI configuration groups for BVCA (p = 0.82) and RV (p = 0.18), but CRT decrease was greater and faster in the posterior vitreous detachment (PVD) group compared to the posterior vitreous attachment (PVA) and vitreous macular adhesion (VMA) groups (p = 0.04). Also, the percentage of patients experiencing a ≥ 20% CRT thickness decrease after intravitreal injection was greater in the PVD group (83%) compared to the VMA (64%) and the PVA (16%) group (p = 0.027), however, not after correction for multiple testing (corrected p-value: 0.11). CONCLUSION The VMI configuration seems to be a factor contributing to treatment efficacy in uveitic CME in terms of CRT decrease, although BCVA outcome did not differ according to VMI status.
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AIM To report the finding of extension of the 4th hyper-reflective band and retinal tissue into the optic disc in patients with cavitary optic disc anomalies (CODAs). METHODS In this observational study, 10 patients (18 eyes) with sporadic or autosomal dominant CODA were evaluated with enhanced depth imaging optical coherence tomography (EDI-OCT) and colour fundus images for the presence of 4th hyper-reflective band extension into the optic disc. RESULTS Of 10 CODA patients (18 eyes), five patients (8 eyes) showed a definite 4th hyper-reflective band (presumed retinal pigment epithelium (RPE)) extension into the optic disc. In these five patients (seven eyes), the inner retinal layers also extended with the 4th hyper-reflective band into the optic disc. Best corrected visual acuity ranged from 20/20 to 20/200. In three patients (four eyes), retinal splitting/schisis was present and in two patients (two eyes), the macula was involved. In all cases, the 4th hyper-reflective band extended far beyond the termination of the choroid into the optic disc. The RPE extension was found either temporally or nasally in areas of optic nerve head excavation, most often adjacent to peripapillary pigment. Compared with eyes without RPE extension, eyes with RPE extension were more myopic (mean dioptres -0.9±2.6 vs -8.8±5, p=0.043). CONCLUSIONS The RPE usually stops near the optic nerve border separated by a border tissue. With CODA, extension of this hyper-reflective band and retinal tissue into the disc is possible and best evaluable using EDI-OCT or analogous image modalities. Whether this is a finding specific for CODA, linked to specific gene loci or is also seen in patients with other optic disc abnormalities needs further evaluation.
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Ocular albinism type 1 (OA1) is an inherited disorder characterized by severe reduction of visual acuity, photophobia, and retinal hypopigmentation. Ultrastructural examination of skin melanocytes and of the retinal pigment epithelium reveals the presence of macromelanosomes, suggesting a defect in melanosome biogenesis. The gene responsible for OA1 is exclusively expressed in pigment cells and encodes a predicted protein of 404 aa displaying several putative transmembrane domains and sharing no similarities with previously identified molecules. Using polyclonal antibodies we have identified the endogenous OA1 protein in retinal pigment epithelial cells, in normal human melanocytes and in various melanoma cell lines. Two forms of the OA1 protein were identified by Western analysis, a 60-kDa glycoprotein and a doublet of 48 and 45 kDa probably corresponding to unglycosylated precursor polypeptides. Upon subcellular fractionation and phase separation with the nonionic detergent Triton X-114, the OA1 protein segregated into the melanosome-rich fraction and behaved as an authentic integral membrane protein. Immunofluorescence and immunogold analyses on normal human melanocytes confirmed the melanosomal membrane localization of the endogenous OA1 protein, consistent with its possible involvement in melanosome biogenesis. The identification of a novel melanosomal membrane protein involved in a human disease will provide insights into the mechanisms that control the cell-specific pathways of subcellular morphogenesis.
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Microtubules play an important role in establishing cellular architecture. Neuronal microtubules are considered to have a role in dendrite and axon formation. Different portions of the developing and adult brain microtubules are associated with different microtubule-associated proteins (MAPs). The roles of each of the different MAPs are not well understood. One of these proteins, MAP1B, is expressed in different portions of the brain and has been postulated to have a role in neuronal plasticity and brain development. To ascertain the role of MAP1B, we generated mice which carry an insertion in the gene by gene-targeting methods. Mice which are homozygous for the modification die during embryogenesis. The heterozygotes exhibit a spectrum of phenotypes including slower growth rates, lack of visual acuity in one or both eyes, and motor system abnormalities. Histochemical analysis of the severely affected mice revealed that their Purkinje cell dendritic processes are abnormal, do not react with MAP1B antibodies, and show reduced staining with MAP1A antibodies. Similar histological and immunochemical changes were observed in the olfactory bulb, hippocampus, and retina, providing a basis for the observed phenotypes.
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PURPOSE: To evaluate visual results with two multifocal diffractive lenses designed with the same platform but with different additions. SETTING: Grupo Innova Ocular clinics. METHODS: A total of 50 eyes from 50 patients were included. Group 1 (n = 25) was implanted with the TECNIS® 1 ZLB +3.25 and group 2 (n = 25) with the TECNIS® 1 ZKB +2.75. Patients were assessed at 24 hours, 1 week and 1 month postoperatively. At surgical discharge, corrected (CDVA) and uncorrected distance visual acuity (UCDVA), near visual acuity (VA) at 25, 40 and 80 cm, visual quality and the defocus curve were measured. RESULTS: Changes in sphere and spherical equivalent were statistically significant (p<0.01) in both groups at 1 week and 1 month compared to preoperative values. In group 1, UCDVA logMAR at 1 month was 0.06 ± 0.02. In group 2, UCDVA at 1 month was 0.03 ± 0.03. In near vision, the TECNIS® 1 ZLB group obtained a VA logMAR of 0.35 ± 0.02 at 25 cm, 0.13 ± 0.02 at 40 cm and 0.27 ± 0.02 at 80 cm, while in the TECNIS® 1 ZKB group, the values were 0.38 ± 0.03, 0.14 ± 0.03 and 0.23 ± 0.06, respectively. No statistically significant differences were found either when results for visual quality were compared. CONCLUSION: Both the TECNIS® 1 ZLB and TECNIS® 1 ZKB are excellent options for obtaining good distance and near vision, in addition to providing good intermediate vision, especially at distances such as those required for working with computers.
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PURPOSE: To compare disk halo size in response to a glare source in eyes with an aspheric apodized diffractive multifocal intraocular lens (IOL) or aspheric monofocal IOL. SETTING: Rementeria Ophthalmological Clinic, Madrid, Spain. DESIGN: Prospective randomized masked study. METHOD: Halo radius was measured using a vision monitor (MonCv3) with low-luminance optotypes in eyes that had cataract surgery and bilateral implantion of an Acrysof Restor SN6AD1 multifocal IOL or Acrysof IQ monofocal IOL 6 to 9 months previously. The visual angle subtended by the disk halo radius was calculated in minutes of arc (arcmin). Patient complaints of halo disturbances were recorded. Monocular uncorrected distance visual acutity (UDVA) and corrected distance visual acuity (CDVA) were measured using high-contrast (96%) and low-contrast (10%) logMAR letter charts. RESULTS: The study comprised 39 eyes of 39 subjects (aged 70 to 80 years); 21 eyes had a multifocal IOL and 18 eyes a monofocal IOL. The mean halo radius was 35 arcmin larger in the multifocal IOL group than the monofocal group (P<.05). Greater halo effects were reported in the multifocal IOL group (P<.05). The mean monocular high-contrast UDVA and low-contrast UDVA did not vary significantly between groups, whereas the mean monocular high-contrast CDVA and low-contrast CDVA were significantly worse at 0.12 logMAR and 0.13 logMAR in the multifocal than in the monofocal IOL group, respectively (P <.01). A significant positive correlation was detected by multiple linear regression between the halo radius and low-contrast UDVA in the multifocal IOL group (r = 0.72, P<.001). CONCLUSIONS: The diffractive multifocal IOL gave rise to a larger disk halo size, which was correlated with a worse low-contrast UDVA.
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Tema 2. Actividad voluntaria nº 2.
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Purpose: To examine a single-optic accommodating intraocular lens (IOL) visual performance by correlating IOL implanted eyes’ defocus curve with the intraocular aberrometric profile and the impact on the quality of life (QOL). Methods: Prospective consecutive case series study including a total of 25 eyes of 14 patients with ages ranging between 52 and 79 years old. All cases underwent cataract surgery with implantation of the single-optic accommodating IOL Crystalens HD (Bausch & Lomb). Distance and near visual acuity outcomes, intraocular aberrations, the defocus curve and QOL (NEI VFQ-25) were evaluated 3 months after surgery. Results: A significant improvement in distance visual acuity was found postoperatively (p = 0.02). Mean postoperative LogMAR uncorrected near visual acuity was 0.44 ± 0.23 (20/30). 60% of eyes had a postoperative addition between 0 and 1.5 diopters (D). The defocus curve showed an area of maximum visual acuity for the levels of defocus corresponding to distance and intermediate vision (−1 to +0.5 D). Postoperative intermediate visual acuity correlated significantly some QOL indices (r ≥ 0.51, p ≤ 0.03; difficulty in going down steps or seeing how people react to things that patient says) as well as with J0 component of manifest cylinder. Postoperative distance-corrected near visual acuity correlated significantly with age (r = 0.65, p < 0.01). Conclusions: This accommodating IOL seems to be able to restore the distance visual function as well as to provide an improvement in intermediate and near vision with a significant impact on patient's QOL, although limited by age and astigmatism. Future studies with larger sample sizes should confirm all these trends.
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Background To evaluate and report the visual, refractive, and aberrometric outcomes of LASIK for the correction of low to moderate hyperopia in a pilot group using a commercially available solid-state laser. Methods Prospective pilot study including 11 consecutive eyes with low to moderate hyperopia of six patients undergoing LASIK surgery using the Pulzar Z1 solid-state laser (CustomVis Laser Pty Ltd., currently CV Laser). Visual, refractive, and aberrometric changes were evaluated. Potential complications were evaluated as well. Mean follow-up time was 6.6 months (range, 3 to 11 months). Results A significant improvement in LogMAR uncorrected distance visual acuity (UDVA) was observed postoperatively (p = 0.01). No significant change was detected in LogMAR corrected distance visual acuity (CDVA) (p = 0.21). Postoperative LogMAR UDVA was 0.1 (about 20/25) or better in ten eyes (90.9 %). Mean overall efficacy and safety indices were 1.03 and 1.12. Postoperatively, no losses of lines of CDVA were observed. Postoperative spherical equivalent was within ±1.00 D in ten eyes (90.9 %). With regard to aberrations, no statistically significant changes were found in higher order and primary coma RMS postoperatively (p ≥ 0.21), and only minimal but statistically significant negativization of primary spherical aberration (p = 0.02) was observed. No severe complications were observed. Conclusion LASIK surgery using the solid-state laser technology seems to be a useful procedure for the correction of low to moderate hyperopia, with minimal induction of higher order aberrations.
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Purpose: To compare outcomes of big-bubble deep anterior lamellar keratoplasty (DALK) and penetrating keratoplasty (PK) for macular corneal dystrophy. Design: Prospective, randomized, interventional case series. Methods: Setting: Single hospital. Patients: Eighty-two eyes of 54 patients requiring keratoplasty for the treatment of macular corneal dystrophy without endothelial involvement were included. Main outcome measures: Operative complications, uncorrected visual acuity, best-corrected visual acuity, contrast sensitivity function, higher-order aberrations, and endothelial cell density were evaluated. Results: The DALK and PK group consisted of 35 and 41 eyes, respectively. Best-corrected visual acuity after surgery was 20/40 or better 68.5% and 70.7% of the eyes in the DALK and PK groups, respectively (P > .05). No statistically significant differences between groups were found in contrast sensitivity function with and without glare for any spatial frequency (P > .05). Significantly higher levels of higher-order aberrations were found in the DALK group (P < .01). In both groups, a progressive and statistically significant reduction in endothelial cell density was found (P < .01). At the last follow-up, the mean endothelial cell loss was 18.1% and 26.9% in DALK and PK groups, respectively (P = .03). Graft rejection episodes were seen in 5 eyes (12.1%) in the PK group, and regrafting was necessary in 3 eyes (7.3%). Recurrence of the disease was documented in 5.7% and 4.8% of the eyes in the DALK and PK groups, respectively. Conclusions: Deep anterior lamellar keratoplasty with the big-bubble technique provided comparable visual and optical results as PK and resulted in less endothelial damage, as well as eliminating endothelial rejection in macular corneal dystrophy. Deep anterior lamellar keratoplasty surgery is a viable option for macular corneal dystrophy without endothelial involvement.
Reverse Geometry Hybrid Contact Lens Fitting in a Case of Donor-Host Misalignment after Keratoplasty
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Purpose: To report the successful outcome obtained after fitting a new hybrid contact lens in a cornea with an area of donor-host misalignment and significant levels of irregular astigmatism after penetrating keratoplasty (PKP). Materials and methods: A 41-year-old female with bilateral asymmetric keratoconus underwent PKP in her left eye due to the advanced status of the disease. One year after surgery, the patient referred a poor visual acuity and quality in this eye. The fitting of different types of rigid gas permeable contact lenses was performed, but with an unsuccessful outcome due to contact lens stability problems and uncomfortable wear. Scheimpflug imaging evaluation revealed that a donor-host misalignment was present at the nasal area. Contact lens fitting with a reverse geometry hybrid contact lens (Clearkone, SynergEyes Carlsbad) was then fitted. Visual, refractive, and ocular aberrometric outcomes were evaluated during a 1-year period after the fitting. Results: Uncorrected distance visual acuity improved from a prefitting value of 20/200 to a best corrected postfitting value of 20/20. Prefitting manifest refraction was +5.00 sphere and -5.50 cylinder at 75°, with a corrected distance visual acuity of 20/30. Higher order root mean square (RMS) for a 5 mm pupil changed from a prefitting value of 6.83 µm to a postfitting value of 1.57 µm (5 mm pupil). The contact lens wearing was referred as comfortable, with no anterior segment alterations. Conclusion: The SynergEyes Clearkone contact lens seems to be another potentially useful option for the visual rehabilitation after PKP, especially in cases of donor-host misalignment.
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Objetivo: Evaluar los resultados obtenidos mediante el empleo de los filtros de Bangerter en casos de ambliopía media o moderada asociada a estrabismo. Material y métodos: Se realizó un estudio prospectivo con 30 pacientes de edades comprendidas entre 2 y 9 años con ambliopía media o moderada unilateral asociada a estrabismo. Todos los pacientes fueron tratados mediante la prescripción del empleo de filtros de Bangerter en el ojo no ambliope junto a su corrección refractiva. En todos los casos el filtro seleccionado indujo una reducción de la agudeza visual de 2 líneas por debajo de la agudeza visual corregida (AVCC) del ojo ambliope. Se realizó un seguimiento durante un periodo de 12 meses. Resultados: Se observó una mejoría estadísticamente significativa en la AVCC del ojo ambliope a los 3 meses (p<0.01), con mejorías adicionales a los 6, 9 y 12 meses (p≤0,02).La AVCC en los ojos no ambliopes permaneció sin cambios durante los primeros 6 meses de tratamiento (p≥0,52), con una mejoría significativa a los 9 meses (p=0,03). Sólo se evidenciaron diferencias significativas en la AVCC entre los ojos ambliopes y los ojos sanos a los 3 meses tras el uso de los filtros (p<0,01). La densidad del filtro tuvo que ser cambiada durante el seguimiento en 12 ojos (40%). Se encontró correlación inversa significativa entre la densidad del filtro y la AVCC al final del seguimiento (r≤-0,35, p≤0,01).Conclusiones: Los filtros de Bangerter son útiles para el tratamiento de la ambliopía media o moderada asociada a estrabismo, si bien la inversión de la dominancia ocular debe ser mantenida a lo largo del tratamiento para optimizar los resultados.
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Purpose: To evaluate postoperative spectral-domain optical coherence tomography findings after macular hole surgery. Methods: Retrospective, interventional, nonrandomized study. Overall, 164 eyes of 157 patients diagnosed with macular hole were operated on by vitrectomy and internal limiting membrane peeling. Preoperative and postoperative best-corrected visual acuity and spectral-domain optical coherence tomography images were obtained. Two groups were considered on the basis of the postoperative integrity of the back reflection line from the ellipsoid portion of the photoreceptor inner segment: group A (disruption of ellipsoid portion of the inner segment line, 60 eyes) and group B (restoration of ellipsoid portion of the inner segment line, 104 eyes). Results: Logarithm of the minimum angle of resolution best-corrected visual acuity improved significantly after the surgery of macular hole from a mean preoperative value of 0.79 ± 0.37 (range, 0.15–2.00) to a mean postoperative value of 0.35 ± 0.31 (range, 0.00–1.30) at the last follow-up visit (P < 0.01). Best-corrected visual acuity improved significantly in the 2 groups analyzed (all P < 0.01). A larger improvement was found in group B than in group A (P < 0.01). Conclusion: Ellipsoid portion of the inner segment line reconstruction seems to be a good prognostic factor for visual rehabilitation after macular hole surgery.