Search results for "Vision disorder"
showing 10 items of 66 documents
Magnitude, temporal trends, and projections of the global prevalence of blindness and distance and near vision impairment: a systematic review and me…
2017
PubMed: 28779882
Evaluation of the practicality of optical biometry and applanation ultrasound in 253 eyes
2003
Abstract Purpose To evaluate the percentage of eyes that could not be measured using optical biometry and ultrasound applanation and the reasons. Setting Department of Ophthalmology, Johannes Gutenberg-University Hospital, Mainz, Germany. Methods Optical biometry (IOLMaster®, Carl Zeiss Meditec AG) and A-scan ultrasound biometry were performed consecutively in 253 eyes scheduled for cataract surgery the next day. Lens opacities were evaluated with the Opacity Lensmeter (Interzeag), and a slitlamp examination and measurement of visual acuity were performed. The 2 techniques were compared in terms of the rate of and reasons for primary measurement failure. Results Measurement with the IOLMast…
Contrast sensitivity and glare disability by halogen light after monofocal and multifocal lens implantation
2000
BACKGROUND—Standard examination of contrast sensitivity under conditions of glare disability is performed with incandescent light. A new halogen glare test that simulates glare as seen with oncoming vehicle headlights was used to measure glare disability in patients implanted with multifocal and monofocal intraocular lenses (IOLs). METHODS—28 patients with an average age of 69 years (SD 12 years) were implanted with a monofocal IOL (SI-40NB, Allergan) and 28 patients with an average of 66 years (12 years) were implanted with a refractive multifocal IOL (Array-SA-40N, Allergan). All patients were followed for 5 months postoperatively. Contrast sensitivity at four spatial frequencies (3, 6, 1…
Balance control interferes with the tracing performance of a pattern with mirror-reversed vision in older persons
2014
When tracing a template with mirror-reversed vision (or distorted vision), the sensory information arising from the movement does not match the expected sensory consequences. In such situations, participants have to learn a new visuomotor mapping in order to trace the template with an accuracy and speed approaching that observed when tracing with direct vision. There are several suggestions that such visuomotor learning requires lowering the gain of the proprioceptive inputs. Generally, subjects learn this task in a seated condition offering a stable postural platform. Adapting to the new visuomotor relationship in a standing condition could add complexity and even hinder sensorimotor adapt…
Posterior chamber phakic intraocular lenses to correct high myopia: A comparative study between Staar and Adatomed models
2001
ABSTRACT PURPOSE: To determine the feasibility of using posterior chamber phakic intraocular lenses (PIOLs) to treat high myopia, comparing two different models, Staar and Adatomed. METHODS: Twenty-four eyes from 12 patients were studied prospectively. A phakic Staar IOL was implanted in one eye of each patient, and the other eye received a phakic Adatomed IOL. Patients with uveitis or ocular trauma prior to ocular surgery, diabetic retinopathy, or capsular pseudoexfoliation were excluded. The mean preoperative spherical equivalent refraction was -16.00 ± 5.05 D for the Staar group and -15.39 ± 2.83 D for the Adatomed group. Average follow-up was 32.4 months (range, 19 to 46 mo) for the Ada…
Long-term observation of endocrine ophthalmopathy and retrospective appraisal of therapeutic measures.
1990
The course of endocrine ophthalmopathy was investigated on the basis of clinical and biochemical parameters and in relation to different therapeutic strategies. A retrospective appraisal was made of 297 patients (44 +/- 14 yr, 249 women) with inclusion of anamnestic and clinical data as well as the results of computer tomography. At the beginning of therapy, 253 patients were hyperthyroid, 36 were euthyroid and eight were hypothyroid. The HLA typing carried out in 89 patients showed the phenotypes B8 and DR3 in 32% and 42% of the cases, respectively. Raised microsomal antibodies were present in 56% of the patients and there were raised thyroglobulin antibodies in 19%. Sixty-three % of the p…
Intrastromal corneal ring segment implantation in paracentral keratoconus with coincident topographic and coma axis.
2012
To evaluate the efficacy, predictability, and safety of implantation of Ferrara-type intrastromal corneal ring segments (ICRS) for refractive correction of paracentral keratoconus.Fernández-Vega Ophthalmological Institute, Oviedo, Spain.Cohort study.Snellen uncorrected (UDVA) and corrected (CDVA) distance visual acuities and residual refractive errors were recorded before and 6 months after ICRS implantation for keratoconus. The tunnels for ICRS implantation were created with a femtosecond laser. The power vector and the Alpins method were used to analyze postoperative refractive outcomes.The study evaluated 56 eyes of 49 patients. The mean UDVA was 0.17 ± 0.14 (SD) preoperatively and 0.41 …
Prevalence and causes of blindness and low vision in the Casteldaccia Eye Study.
1994
In a population-based survey performed on the middle-aged and elderly population of Casteldaccia, Sicily, we found that the prevalence of blindness was 0.47% and the prevalence of low vision 1.22%. Unilateral blindness affected 2.81% of the population and unilateral low vision 4.12%. Visual impairment was much more frequently seen in subjects aged 70 years or more than in younger persons. The main cause of visual impairment was cataract, followed by amblyopia, which was responsible for many cases of unilateral low vision.
Objective vs Subjective Vault Measurement After Myopic Implantable Collamer Lens Implantation
2009
PURPOSE: To evaluate the relationship between subjective measurements of vault and objective values measured with Visante optical coherence tomography (OCT) in eyes receiving an implantable contact lens (ICL) for myopia correction. DESIGN: Observational cross-sectional study. METHODS: SETTING: Fernández-Vega Ophthalmological Institute, Oviedo, Spain. PATIENTS: Four hundred and fifty-two eyes from 246 patients were elected to be implanted with a Visian ICL V4 (STAAR Surgical Inc, Monrovia, California, USA). OBSERVATION PROCEDURES: Subjective and objective measurements of vault after implantation of ICL. MAIN OUTCOME MEASURES: Subjective vault classified in 5 levels assessed using an optical …
Mesopic Contrast Sensitivity Function After Laser in situ Keratomileusis
2003
ABSTRACT PURPOSE: To evaluate contrast sensitivity under mesopic conditions in patients who have undergone uncomplicated bilateral laser in situ keratomileusis (LASIK) for myopia. METHODS: Best-corrected monocular contrast sensitivity was measured with the Stereo Optical F.A.C.T. chart at 1.5, 3, 6, 12, and 18 c/deg in 20 patients (20 left eyes) before and after bilateral LASIK (with the Nidek EC-5000 excimer laser and the Automated Corneal Shaper). Mean preoperative refractive error was -6.40 ± 1.28 D (range -4.00 to -8.00 D) and postoperative mean refractive error was -0.41 ± 0.45 D (range -0.75 to +0.50 D). Contrast sensitivity function was measured before and 6 months after surgery usin…