Search results for "structures"
showing 10 items of 4815 documents
Oxidative Stress in Diabetic Retinopathy
2021
Diabetic Retinopathy (DR) is a progressive asymptomatic neuro-vascular complication of diabetes that triggers irreversible retinal damage [...]
Übereinstimmung von klinischer Beurteilung, Heidelberg-Retina-Tomograph (HRT) und Nerve Fiber Analyzer (GDx) in der Glaukomdiagnostik
2004
BACKGROUND We have made a comparison of clinical evaluation, Heidelberg-Retina-Tomograph (HRT) and Nerve Fiber Analyzer (GDx) in diagnosing glaucoma. MATERIALS AND METHODS One eye of 38 glaucoma patients and 26 non-glaucoma patients was examined with HRT and GDx. Assignment of the patients into the two groups by clinical evaluation was performed on the basis of visual field and optic disc results. As classification criterion for glaucoma/non-glaucoma by means of the instruments we employed the statistical classification of the HRT and "the number" of the GDx. Statistical analysis was performed with Cohen's kappa and McNemar tests. Additionally, ROC curves for evaluation of the sensitivity a…
Effect of Phenylephrine on the Accommodative System
2016
Accommodation is controlled by the action of the ciliary muscle and mediated primarily by parasympathetic input through postganglionic fibers that originate from neurons in the ciliary and pterygopalatine ganglia. During accommodation the pupil constricts to increase the depth of focus of the eye and improve retinal image quality. Researchers have traditionally faced the challenge of measuring the accommodative properties of the eye through a small pupil and thus have relied on pharmacological agents to dilate the pupil. Achieving pupil dilation (mydriasis) without affecting the accommodative ability of the eye (cycloplegia) could be useful in many clinical and research contexts. Phenylephr…
Spotlight on fundus autofluorescence.
2018
Fundus autofluorescence (FAF) imaging is based on the fluorescence from ocular endogenous fluorophores located in the retinal pigment epithelium and choroid, mainly lipofuscin and melanin. It is a noninvasive technique that provides information about the spatial distribution of lipofuscin/melanin and retinal pigment epithelium health status. An overview about the fluorophores responsible for FAF imaging and the usefulness of FAF imaging in the noninvasive assessment and monitoring of retinal diseases, such as age-related macular degeneration, diabetic retinopathy, diabetic macular edema, central serous chorioretinopthy, retinitis pigmentosa and retinal dystrophies, are discussed in this rev…
Premedication with midazolam in intellectually disabled dental patients: Intramuscular or oral administration? A retrospective study
2016
Background: The use of midazolam for dental care in patients with intellectual disability is poorly documented. The purpose of this study was to determine which method of premedication is more effective for these patients, 0.15 mg/kg of intramuscular midazolam or 0.3 mg/kg of oral midazolam. Material and Methods: This study was designed and implemented as a non-randomized retrospective study. The study population was composed of patients with intellectual disability who required dental treatment under ambulatory general anesthesia from August 2009 through April 2013. Patients were administered 0.15 mg/kg of midazolam intramuscularly (Group IM) or 0.3 mg/kg orally (Group PO). The predictor v…
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…
Long-term physical activity modifies automatic visual processing
2017
Electrophysiologically registered visual mismatch negativity (vMMN) is known to represent automatic visual processing in human visual cortex. Since physical activity (PA) is generally beneficial to cerebrovascular function, we wanted to find out if automatic visual processing is affected by PA. We investigated the connection between long-term leisure-time PA and precognitive visual processing in 32 healthy young males. Participants were divided into active (n = 16) and inactive (n = 16) group according to their leisure-time PA records from the past three years. vMMN was recorded with electroencephalogram using passive oddball paradigm with visual bars. Standard (90%) and deviant (10%) stimu…
Preliminary in vivo positional analysis of a posterior chamber phakic intraocular lens by optical coherence tomography and its correlation with clini…
2012
Purpose: To analyze by spectral-domain optical coherence tomography the anatomical relationship of a specific type of posterior chamber phakic intraocular lens (pIOL) implanted in cases of high to moderate myopia with the adjacent intraocular structures and to correlate it with clinical outcomes. Methods: Prospective observational case series including 18 eyes with high to moderate myopia (spherical equivalent between −5.88 and −15.75 D) of 9 patients (age range, 29–49 years) undergoing bilateral Phakic Refractive Lens (PRL, Zeiss) implantation. Postoperative visual acuity, refraction, contrast sensitivity (CS), and ocular higher order aberrations (HOA) were evaluated. Furthermore, the in v…
Validity of automated refraction after segmented refractive multifocal intraocular lens implantation
2017
Aim To evaluate the clinical utility of automated refraction (AR) and keratometry (KR) compared with subjective or manifest refraction (MR) after cataract or refractive lens exchange surgery with implantation of Lentis Mplus X (Oculentis GmbH) refractive multifocal intraocular lens (IOL). Methods Eighty-six eyes implanted with the Lentis Mplus X multifocal IOL were included. MR was performed in all patients followed by three consecutive AR measurements using the Topcon KR-8000 autorefractor. Assessment of repeatability of consecutive AR before and after dilation with phenylephrine 10%, and comparison of the AR and KR with MR using vector analysis were performed at 3mo follow-up. Results Ana…
The Effects of Stochastic Galvanic Vestibular Stimulation on Body Sway and Muscle Activity
2020
Objective: This study aimed to investigate whether galvanic vestibular stimulation with stochastic noise (nGVS) modulates the body sway and muscle activity of the lower limbs, depending on visual and somatosensory information from the foot using rubber-foam.Methods: Seventeen healthy young adults participated in the study. Each subject maintained an upright standing position on a force plate with/without rubber-foam, with their eyes open/closed, to measure the position of their foot center of pressure. Thirty minutes after baseline measurements under four possible conditions (eyes open/closed with/without rubber-foam) performed without nGVS (intensity: 1 mA, duration: 40 s), the stimulation…