Search results for "VISION"
showing 10 items of 5066 documents
Use of digital displays and ocular surface alterations: A review.
2020
Digital display use has been accepted to be implicated as a contributing factor for dry eye disease (DED). Abnormal blinking during computer operation, including a reduced blink rate and an incomplete eyelid closure, increased palpebral fissure as consequence of high visualization angles, and meibomian gland dysfunction associated to long-term display use, are behind the increased prevalence of dry eye signs and symptoms found in digital display users. Previous research reveals significant reductions in tear volume and stability, alterations in tear film composition, including increased osmolarity, inflammatory cytokines, oxidative stress markers and reduced mucin secretion, eyelid abnormal…
Interferon löst okuläre Ischämien aus
2006
Background: Reports of interferon-associated retinopathy mainly originate from Japanese working groups. Only a few cases have been described in Europe. Patients and Methods: We have performed a retrospective analysis of the patients who were examined in the University Eye Clinic in Mainz complaining of visual loss associated with systemic interferon therapy in the time span between January 2001 and December 2003. Results: 12 patients (age 35-67 years), undergoing treatment with interferon alpha for hepatitis C, metastatic renal cell carcinoma, leukaemia and malignant melanoma of the skin, complained of blurred vision 2 - 10 weeks after the start of interferon therapy. Fundus examination rev…
Color-discrimination threshold determination using pseudoisochromatic test plates
2014
We produced a set of pseudoisochromatic plates for determining individual color-difference thresholds to assess test performance and test properties, and analyzed the results. We report a high test validity and classification ability for the deficiency type and severity level [comparable to that of the fourth edition of the Hardy–Rand–Rittler (HRR) test]. We discuss changes of the acceptable chromatic shifts from the protan and deutan confusion lines along the CIE xy diagram, and the high correlation of individual color-difference thresholds and the red–green discrimination index. Color vision was tested using an Oculus HMC anomaloscope, a Farnsworth D15, and an HRR test on 273 schoolchildr…
Changes in Pupil Area during Low-energy Femtosecond Laser-assisted Cataract Surgery
2018
Purpose: To study the potential changes in pupil area within low-energy femtosecond-laser assisted cataract surgery (FLACS). Methods: A retrospective assessment of the pupil size was performed in the eyes undergoing FLACS using the Ziemer LDV Z8. We measured the pupil diameters as part of the images taken preoperatively and at the completion of laser pretreatment (after releasing the suction). We calculated the pupil area in 40 eyes of 40 patients (14 right and 26 left eyes). The mean ± standard deviation (SD) of age of the patients was 74 ± 7.4 years (range: 51-87). Paired t-test was used for statistical analyses. Subgroups were built with reference to age and preoperative pupil area (smal…
Role of the tear film in the optical quality of the human eye.
2007
This paper reviews recent studies of the role of the tear film in the optical quality of the eye. Recent investigations focus on the dynamics of the tear film after a blink and its important role in the optical quality of the eye. The results in this review were used in an attempt to understand the optical and visual impact of tear-film breakup in normal eyes and dry eyes. It was noted that patients with dry-eye syndrome have large optical aberrations compared with those in normal eyes, which may be the cause of blurry vision associated with the syndrome. In addition, instillation of artificial tears reduces optical aberrations and thus improves the optical quality of vision in these patien…
Binocular Vision in Patients with Multiple Sclerosis.
2021
Amparo Gil-Casas,1,2 David P Piñero-Llorens,2 Ainhoa Molina-Martin2 1Clínica Optométrica, Fundació Lluís Alcanyís, University of Valencia, Valencia, Spain; 2Optics and Visual Perception Group (GOPV), Department of Optics, Pharmacology, and Anatomy, University of Alicante, Alicante, SpainCorrespondence: Ainhoa Molina-MartinDepartment of Optics, Pharmacology, and Anatomy, University of Alicante, Carretera San Vicente del Raspeig, San Vicente del Raspeig, 03690, Alicante, SpainTel +34 965 903-400Email ainhoa.molina@ua.esPurpose: Oculomotor disorders have been reported in multiple sclerosis (MS) in up to 80% of cases. There have …
Real-Time Augmented Reality for Ear Surgery
2018
International audience; Transtympanic procedures aim at accessing the middle ear structures through a puncture in the tympanic membrane. They require visualization of middle ear structures behind the eardrum. Up to now, this is provided by an oto endoscope. This work focused on implementing a real-time augmented reality based system for robotic-assisted transtympanic surgery. A preoperative computed tomography scan is combined with the surgical video of the tympanic membrane in order to visualize the ossciles and labyrinthine windows which are concealed behind the opaque tympanic membrane. The study was conducted on 5 artificial and 4 cadaveric temporal bones. Initially, a homography framew…
RGB mapping of hemoglobin distribution in skin
2011
An experimental RGB imaging system based on commercial color camera was constructed, and its potential for mapping of hemoglobin distribution in skin was studied. Two types of LEDs (RGB and white “warm” LEDs) were compared as illuminators for acquiring images of vascular and pigmented skin malformations. A novel approach for studies of skin capillary refill by RGB analysis has been proposed and discussed.
Advances in detection and characterization of atherosclerosis using contrast agents targeting the macrophage
2006
With advances in imaging technology and our understanding of the role of inflammation in atherosclerosis, the macrophage appears to be an excellent target for imaging the progression of disease. In addition to imaging the macrophage with only 1 modality, contrast agents can be created that can be imaged with multiple modalities. This seems extremely attractive, as lesion morphology and characteristics can be determined with modalities that provide high picture resolution, such as CT or MRI, whereas macrophage quantity can be accurately determined through the creation of a radiolabeled contrast agent such as FDG via PET. Although this combination of imaging technologies may yield clinically …
A multiparametric magnetic resonance imaging-based virtual reality surgical navigation tool for robotic-assisted radical prostatectomy
2019
Objective Increased computational power and improved visualization hardware have generated more opportunities for virtual reality (VR) applications in healthcare. In this study, we test the feasibility of a VR-assisted surgical navigation system for robotic-assisted radical prostatectomy. Material and methods The prostate, all magnetic resonance imaging (MRI) visible tumors, and important anatomic structures like the neurovascular bundles, seminal vesicles, bladder, and rectum were contoured on a multiparametric MRI using an in-house segmentation software. Three-dimensional (3-D) VR models were rendered and evaluated in a side room of the operating room. While interacting with the VR platfo…