Search results for "Visual Acuity"

showing 10 items of 456 documents

An alternative clinical routine for subjective refraction based on power vectors with trial frames.

2016

PURPOSE Subjective refraction determines the final point of refractive error assessment in most clinical environments and its foundations have remained unchanged for decades. The purpose of this paper is to compare the results obtained when monocular subjective refraction is assessed in trial frames by a new clinical procedure based on a pure power vector interpretation with conventional clinical refraction procedures. METHODS An alternative clinical routine is described that uses power vector interpretation with implementation in trial frames. Refractive error is determined in terms of: (i) the spherical equivalent (M component), and (ii) a pair of Jackson Crossed Cylinder lenses oriented …

AdultMaleRefractive errorCorrelation coefficientAdolescentVisual AcuityAstigmatismRefraction Ocular01 natural sciences010309 optics03 medical and health sciencesYoung Adult0302 clinical medicineOptics0103 physical sciencesmedicineHumansPhoropterMathematicsMonocularbusiness.industryOrientation (computer vision)Vision TestsEquipment Designmedicine.diseaseRefractive ErrorsSubjective refractionRefractionSensory SystemsOphthalmologyEyeglasses030221 ophthalmology & optometryFemalebusinessAlgorithmOptometryOphthalmicphysiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)
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Postoperative astigmatism and rotational stability after Artisan toric phakic intraocular lens implantation

2003

Abstract Purpose To evaluate deviations in the axis (intended versus achieved) and postoperative astigmatism after implantation of an Artisan toric phakic intraocular lens (IOL). Setting University Eye Hospital, Mainz, Germany. Methods This prospective study comprised 29 eyes with high ametropia and astigmatism. All eyes had uneventful implantation of a toric phakic IOL through a superior scleral tunnel incision at 12 o’clock. After a minimum of 6 months, the uncorrected visual acuity (UCVA), best correct visual acuity, refraction, and astigmatism were analyzed in all eyes. A multivariate analysis of postoperative astigmatism was performed. Results After a follow-up of at least 6 months, 95…

AdultMaleRefractive errorVisual acuityRotationgenetic structuresmedicine.medical_treatmentEmmetropiaIntraocular lensPhakic intraocular lensLens Implantation IntraocularmedicineHumansPostoperative PeriodProspective StudiesDioptreLenses Intraocularbusiness.industryAstigmatismEquipment DesignMiddle AgedRefractive Errorsmedicine.diseaseeye diseasesSensory SystemsRefractive Surgical ProceduresToric lensOphthalmologyMeridian (perimetry visual field)OptometryFemaleSurgerysense organsmedicine.symptombusinessJournal of Cataract and Refractive Surgery
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Rate of Cataract Formation in 343 Highly Myopic Eyes After Implantation of Three Types of Phakic Intraocular Lenses

2004

ABSTRACT PURPOSE: To assess the feasibility of using phakic intraocular lenses (PIOL) to treat high myopia, and evaluate the incidence of cataract, comparing three different lens types. METHODS: From 1989 to 2002, we implanted three different phakic intraocular lenses (PIOL) in 343 eyes of 232 patients; 231 eyes recieved an Ophtec (Worst-Fechner model, iris-claw), 89 an Adatomed (silicone posterior chamber), and 23 a Staar (posterior chamber, models V2, V3, V4). Average follow-up was 96.2 months for the Ophtec group, 31.5 months for the Adatomed group, and 19.3 months for Staar group. Eyes that subsequently developed cataract were studied for clinical evolution and had PIOL explantation and…

AdultMaleRefractive errormedicine.medical_specialtyAnterior subcapsular cataractVisual acuitygenetic structuresEye diseasemedicine.medical_treatmentVisual AcuityIntraocular lensPhakic intraocular lensCataractlaw.inventionLens Implantation IntraocularlawOphthalmologyMyopiamedicineHumansDevice RemovalAgedLenses Intraocularbusiness.industryIncidencePhacoemulsificationMiddle Agedmedicine.diseaseeye diseasesLens (optics)OphthalmologyFeasibility StudiesFemaleSurgerysense organsmedicine.symptombusinessJournal of Refractive Surgery
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Photodynamic therapy with verteporfin for subfoveal choroidal neovascularization secondary to pathologic myopia: long-term study.

2006

Purpose: To assess the safety and effectiveness of photodynamic therapy (PDT) with verteporfin for subfoveal choroidal neovascularization (CNV) secondary to pathologic myopia (PM). Methods: Sixty-two patients (62 eyes) with PM underwent PDT according to the guidelines of the Verteporfin in Photodynamic Therapy Study. Clinical evaluations performed at all study visits included measurement of best-corrected Snellen visual acuity, slit-lamp biomicroscopy, and fundus fluorescein angiography. Patients were followed up at 1 month and 3 months after treatment and thereafter at 3-month intervals. Results: The final visual acuity of the study patients, after a median follow-up of 31 months, improved…

AdultMaleRefractive errormedicine.medical_specialtyFovea CentralisVisual acuityPorphyrinsgenetic structuresmedicine.medical_treatmentVisual AcuityPhotodynamic therapyOphthalmologyPathologic myopiamedicineHumansProspective StudiesFluorescein AngiographyDioptreAgedAged 80 and overPhotosensitizing Agentsbusiness.industryVerteporfinGeneral MedicineMiddle Agedmedicine.diseaseVerteporfineye diseasesChoroidal NeovascularizationOphthalmologyLong term learningChoroidal neovascularizationPhotochemotherapyMyopia DegenerativeFemalesense organsmedicine.symptombusinessmyopia subfoveal choroidal neovascularization photodynamic therapy verteporfin.medicine.drugFollow-Up StudiesRetina (Philadelphia, Pa.)
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Phakic intraocular lenses to correct high myopia

2003

Abstract Purpose: To evaluate the feasibility and safety of using phakic intraocular lenses (IOLs) to correct high myopia by comparing 3 IOL models: Adatomed, Staar, and Artisan. Setting: La Fe University Hospital, Department of Ophthalmology, and the Fundacion Oftalmologica del Mediterraneo, Valencia, Spain. Methods: In this prospective comparative study, a phakic IOL was implanted in 217 highly myopic eyes (118 patients). Fifty-nine eyes received an Adatomed IOL, 21 eyes a Staar IOL, and 137 eyes an Artisan IOL. The mean preoperative spherical equivalent was −15.39 diopters (D) ± 2.83 (SD), −16.00 ± 5.05 D, and −16.17 ± 2.75 D in the Adatomed, Staar, and Artisan groups, respectively. The …

AdultMaleRefractive errormedicine.medical_specialtyIntraocular pressureAnterior subcapsular cataractVisual acuitygenetic structuresAnterior ChamberEye diseasemedicine.medical_treatmentVisual AcuityIntraocular lensRefraction OcularPhakic intraocular lensCataractPostoperative ComplicationsLens Implantation IntraocularOphthalmologyLens CrystallineMyopiamedicineHumansProspective StudiesIntraocular PressureDioptreLenses Intraocularbusiness.industryMiddle Agedmedicine.diseaseeye diseasesSensory SystemsOphthalmologyFeasibility StudiesFemaleSurgerysense organsSafetymedicine.symptombusinessFollow-Up StudiesJournal of Cataract & Refractive Surgery
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Mesopic contrast sensitivity function after excimer laser photorefractive keratectomy.

2002

ABSTRACT PURPOSE: To evaluate contrast sensitivity under mesopic conditions in patients who had undergone uncomplicated excimer laser photorefractive keratectomy (PRK) for myopia. METHODS: Monocular contrast sensitivity function was measured with the Stereo Optical ?A.C.T. chart in 26 patients who had received PRK using the Nidek EC-5000 excimer laser system. Mean preoperative refractive error was -6.23 ? 1.69 D (range, -4.00 to -8.25 D); postoperatively, mean refractive error was -0.36 ? 0.58 D (range, -0.75 to +0.50 D). Contrast sensitivity function was measured 6 months after surgery using four different chart luminances: 85, 5.0, 2.5, and 0.1 cd/m2, the first being a photopic level and …

AdultMaleRefractive errormedicine.medical_specialtyMaterials scienceLightMesopic visionmedicine.medical_treatmentmedia_common.quotation_subjectVisual AcuityEmmetropiaRefraction OcularExcimerPhotorefractive KeratectomyContrast SensitivityOpticsOphthalmologyMyopiamedicineHumansContrast (vision)media_commonExcimer laserbusiness.industrymedicine.diseaseeye diseasesPhotorefractive keratectomyOphthalmologyFemaleLasers ExcimerSurgerybusinessPhotopic vision
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Iris Claw Phakic Intraocular Lens for High Myopia

1997

ABSTRACT BACKGROUND: The implantation of a WorstFechner iris claw intraocular lens (IOL) is one of the surgical procedures used for the correction of high myopia. This technique reduces myopia with stähle refractive results; however, its potential long-term risks have not been evaluated. We report results in 94 eyes with a minimum follow -up of 3 years. METHODS: We studied 94 eyes of 62 patients with myopia 5= -7.00 diopters (D) who underwent Worst-Fechner IOL implantation. Lens decentration, permeability of the blood-aqueous barrier by iris angiography, and changes in corneal endothelial density were analyzed. RESULTS: Mean follow-up time was 48.9 months (range 36 to 72 mo). Three years af…

AdultMaleRefractive errormedicine.medical_specialtyTime FactorsVisual acuitygenetic structuresEye diseasemedicine.medical_treatmentVisual AcuityIrisEmmetropiaIntraocular lensRefraction OcularPhakic intraocular lensVision disorderPostoperative ComplicationsOphthalmologyMyopiamedicineHumansDioptreAgedRetrospective StudiesLenses Intraocularbusiness.industryEndothelium CornealMiddle Agedmedicine.diseaseeye diseasesOphthalmologyTreatment OutcomeFemaleSurgerysense organsmedicine.symptombusinessFollow-Up StudiesJournal of Refractive Surgery
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Long-term results of surgical treatment of high myopia with Worst-Fechner intraocular lenses

1995

Abstract This retrospective study evaluated the results in 90 eyes that had a minus-power anterior chamber intraocular lens implanted to correct high myopia. Preoperative myopia ranged from −7.00 to −24.00 D. Postoperative spherical equivalent was −0.50 D; 80.5% of eyes were within 1.00 D of emmetropia. Two years postoperatively, no cataract formation, retinal detachment, glaucoma, or significant endothelial damage had occurred. We conclude that minus-power lenses can rapidly, safely, and predictably correct high myopia in phakic patients.

AdultMaleRefractive errormedicine.medical_specialtygenetic structuresAnterior ChamberEye diseasemedicine.medical_treatmentVisual AcuityEmmetropiaGlaucomaIntraocular lensProsthesis DesignVision disorderPostoperative ComplicationsOphthalmologyMyopiamedicineHumansLongitudinal StudiesAgedRetrospective StudiesLenses Intraocularbusiness.industryRetinal detachmentRetrospective cohort studyMiddle AgedPrognosismedicine.diseaseeye diseasesSensory SystemsOphthalmologyFemaleSurgerysense organsmedicine.symptombusinessFollow-Up StudiesJournal of Cataract and Refractive Surgery
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Excimer laser photorefractive keratectomy for high myopia

1995

Abstract One hundred and thirty-three eyes of 103 patients had photorefractive keratectomy with a slit scan mode excimer laser for myopia ranging from −6.00 to −22.00 diopters (D). The epithelium was removed with 20% ethanol, and the ablation was done with a tapered profile surrounding the optical zone. Patients were divided into two groups based on preoperative myopia: Group A, −6.00 D to −12.00 D (88 eyes); Group B, −12.50 D to −22.00 D (45 eyes). In Group A, mean preoperative refraction was −9.59 ± 1.79 D. Mean postoperative refraction was −0.29 ± 1.47 D at one month, −0.85 ± 1.68 D at three months, −1.17 ± 2.04 D at six months, and −0.56 ± 0.74 D at one year. Anterior stromal haze was g…

AdultMaleRefractive errormedicine.medical_specialtygenetic structuresCorneal Stromamedicine.medical_treatmentEye diseaseVisual AcuityRefraction OcularExcimerPhotorefractive KeratectomyEpitheliumCorneaVision disorderCorneal OpacityOphthalmologyMyopiamedicineHumansIntraocular PressureDioptreExcimer laserbusiness.industryMiddle AgedPrognosismedicine.diseaseAblationeye diseasesSensory SystemsPhotorefractive keratectomyOphthalmologyFemaleLasers ExcimerSurgerysense organsmedicine.symptombusinessJournal of Cataract and Refractive Surgery
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Long-term Results After Transconjunctival Resuturing of the Scleral Flap in Hypotony Following Trabeculectomy

2013

Purpose To present the 4-year follow-up results in the surgical treatment of hypotony following trabeculectomy with mitomycin C in glaucoma patients with additional flap sutures. Design Retrospective interventional case series. Methods Since 2006, 53 patients with hypotony maculopathy attributable to overfiltration following glaucoma surgery (trabeculectomy with mitomycin C) were included in this institutional study. We were able to follow up intraocular pressure (IOP) and distance-corrected visual acuity in 33 (62%) over 4 years, whereas all were followed over 2 years. To elevate IOP, we placed tangential transconjunctival sutures through the scleral flap and connected them to the adjacent…

AdultMaleReoperationIntraocular pressuremedicine.medical_specialtyTime FactorsVisual acuitygenetic structuresmedicine.medical_treatmentGlaucomaOcular HypotensionTrabeculectomySurgical FlapsTonometry OcularOphthalmologyGlaucoma surgeryHumansMedicineTrabeculectomyIntraocular PressureAgedRetrospective StudiesScleral flapAged 80 and overbusiness.industrySuture TechniquesMitomycin CGlaucomaMiddle Agedmedicine.diseaseeye diseasesScleraSurgeryOphthalmologyTreatment Outcomemedicine.anatomical_structureFemalesense organsmedicine.symptombusinessConjunctivaScleraFollow-Up StudiesAmerican Journal of Ophthalmology
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