Search results for "Sensory system"
showing 10 items of 1266 documents
Meibomian glands structure in daily disposable soft contact lens wearers: a one‐year follow‐up study
2020
Purpose To assess the impact of daily disposable soft contact lenses on meibomian gland morphology over a period of 12 months. Methods Forty-one subjects (33 experienced and 8 neophytes) were fitted with either silicone-hydrogel or hydrogel daily contact lenses. The study protocol included four visits: baseline, day-2 for contact lens fit and follow-up measurements, as well as after 6 and 12 months of lens wear. Non-contact infrared meibography images were acquired with Keratograph 5M topographer (www.oculus.de) and analysed with an automated method, which objectively estimates the area of gland atrophy, gland length and width, number of glands and gland irregularity. Protocol at follow-up …
Afferent contribution to locomotor muscle activity during unconstrained overground human walking:an analysis of triceps surae muscle fascicles
2010
Plantar flexor series elasticity can be used to dissociate muscle–fascicle and muscle–tendon behavior and thus afferent feedback during human walking. We used electromyography (EMG) and high-speed ultrasonography concomitantly to monitor muscle activity and muscle fascicle behavior in 19 healthy volunteers as they walked across a platform. On random trials, the platform was dropped (8 cm, 0.9 g acceleration) or held at a small inclination (up to ±3° in the parasagittal plane) with respect to level ground. Dropping the platform in the mid and late phases of stance produced a depression in the soleus muscle activity with an onset latency of about 50 ms. The reduction in ground reaction force…
Motor learning without doing: trial-by-trial improvement in motor performance during mental training.
2010
Although there is converging experimental and clinical evidences suggesting that mental training with motor imagery can improve motor performance, it is unclear how humans can learn movements through mental training despite the lack of sensory feedback from the body and the environment. In a first experiment, we measured the trial-by-trial decrease in durations of executed movements (physical training group) and mentally simulated movements (motor-imagery training group), by means of training on a multiple-target arm-pointing task requiring high accuracy and speed. Movement durations were significantly lower in posttest compared with pretest after both physical and motor-imagery training. …
Prevalence and risk factors of diabetic retinopathy in adult and elderly subjects. The Casteldaccia Eye Study
2003
PURPOSE: To investigate the prevalence and risk factors of diabetic retinopathy in subjects aged 40 years or older living in Casteldaccia, Sicily. METHODS: A population-based survey was performed on 1,588 subjects randomly enrolled among people aged 40 years or older. A total of 1,068 persons could be examined and in 1,019 the fundus of the eye was adequately observed (64.2% of the enrolled population). Diabetic retinopathy was diagnosed by ophthalmoscopy and fundus photographs; fluorescein angiography was performed in 91% of retinopathic subjects. In addition, a case-control study was carried out in order to demonstrate the association of diabetic retinopathy with a number of variables. RE…
Clinical outcomes after implantation of a posterior chamber collagen copolymer phakic intraocular lens with a central hole for myopic correction.
2013
Purpose To evaluate the efficacy, predictability, safety, and stability of a new-model posterior chamber Implantable Collamer Lens phakic intraocular lens (pIOL) (V4c Visian) to correct myopia. Setting Private practice, Oviedo, Spain. Design Case series. Methods This study enrolled patients who had implantation of a new pIOL design with a central hole for more natural aqueous flow, eliminating the need for neodymium:YAG iridotomy or peripheral iridectomy. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refractive error, intraocular pressure (IOP), endothelial cell count, central vault, and adverse events were evaluated 6 months postoperatively. Results The study enroll…
Performance of the compensation comparison method for retinal straylight measurement: effect of patient's age on repeatability
2008
Aim: The assessment of repeatability and reproducibility of retinal straylight measurements with the C-Quant straylight meter (Oculus AG, Germany) and the effect of patient’s age on the instrument performance are tested with a series of experiments. Methods: First, 20 eyes from 20 subjects (mean age 26.9 (SD 2.7) years, mean refractive error −1.34 (2.72) D) were examined with the C-Quant straylightmeter, taking 10 consecutive readings. Five subjects were also examined on five consecutive days to assess reproducibility. Additionally, repeated measures of straylight from 84 subjects of ages ranging from 19 to 86 years (mean (SD): 42.4 (24.0) years) were retrospectively analysed to assess the …
Association of low birth weight with myopic refractive error and lower visual acuity in adulthood: results from the population-based Gutenberg Health…
2017
PurposeLow birth weight (BW) is linked to impaired organ development in childhood, including altered ocular morphological and functional development. The aim of this study was to evaluate whether low BW has long-term effects on visual acuity and refraction in adulthood.MethodsThe Gutenberg Health Study is a population-based, observational cohort study in Germany, including 15 010 participants aged between 35 and 74 years. These participants were divided into three different BW groups (low: <2500 g; normal: between 2500 and 4000 g; and high: >4000 g). Best-corrected visual acuity and objective refraction were examined. We used multivariable linear regression models with adjustment for …
Prevalence of myopic maculopathy in the German population: results from the Gutenberg health study.
2019
AimsTo determine the prevalence of myopic maculopathy in the general population in Germany and to analyse potential associations with ocular and systemic factors.DesignThe Gutenberg Health Study is a population-based study, including 15 010 participants aged 35–74 years.MethodsMyopic maculopathy was graded in phakic eyes with spherical equivalent ≤−6 D by assessing fundus photographs according to a recent international photographic classification system (META-PM). 801 eyes of 519 participants (mean age 51.0±0.77 years) met the conditions and had gradable fundus photographs. Age-specific prevalence estimates were computed. Multivariable logistic regression analysis was used to assess associa…
Prevalence of refractive errors in the European adult population: the Gutenberg Health Study (GHS).
2014
Objective To study the distribution of refractive errors among adults of European descent. Design Population-based eye study in Germany with15 010 participants aged 35–74 years. Methods The study participants underwent a detailed ophthalmic examination according to a standardised protocol. Refractive error was determined by an automatic refraction device (Humphrey HARK 599) without cycloplegia. Definitions for the analysis were myopia +0.5 D, astigmatism >0.5 cylinder D and anisometropia >1.0 D difference in the spherical equivalent between the eyes. Exclusion criterion was previous cataract or refractive surgery. Results 13 959 subjects were eligible. Refractive errors ranged from −21.5 to…
A breathing-retraining procedure in treatment of sleep-onset insomnia: theoretical basis and experimental findings.
1995
Increase in CO2 has a sedative effect upon the central nervous system, and the beginning of sleep coincides with modifications in breathing, decrease in ventilation, and in pCO2 increase. In this paper is described a technique of breathing that is useful in producing drowsiness in a very short time. 46 insomniacs were randomly allocated to either a treatment or control condition. In the former, patients were trained in the breathing process. The control group was taught no breathing process. Latencies to sleep for the insomniacs confirmed that the breathing process was useful in producing drowsiness. Theoretical bases are discussed.