Search results for "Sensor"
showing 10 items of 4594 documents
Cortical representation of saccular vestibular stimulation: VEMPs in fMRI
2006
Short tone bursts trigger a vestibular evoked myogenic potential (VEMP), an inhibitory potential which reflects a component of the vestibulocollic reflex (VCR). These potentials arise as a result of activation of the sacculus and are expressed through the vestibulo-collic reflex (VCR). Up to now, the ascending projections of the sacculus are unknown in humans, only the representation of the semicircular canals or the entire vestibular nerve has been demonstrated. The aim of this study was to determine whether a sacculus stimulus that evoked VEMPs could activate vestibular cortical areas in fMRI. To determine this, we studied the differential effects of unilateral VEMP stimulation in 21 heal…
Single versus double femtosecond laser pass for incomplete laser in situ keratomileusis flap in contralateral eyes: Visual and optical outcomes
2011
Purpose To evaluate visual acuity, refractive outcomes, and anterior corneal higher-order aberrations (HOAs) after myopic laser in situ keratomileusis (LASIK) with uneventful single femtosecond laser pass versus double pass performed for intraoperative suction loss. Setting Private refractive surgery center, Valencia, Spain. Design Cohort study. Methods After the LASIK flap was created with a single pass of an Intralase femtosecond laser in 1 eye and a double pass in the fellow eye, the ablation was performed with a Visx S2 laser. At 12 months, the refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, and anterior corneal HOAs were measured with 4.0 mm and 6.0 mm pup…
Effects of intraocular cefotaxime on the human corneal endothelium
2001
Abstract Purpose To ascertain whether 0.4 mL of cefotaxime 0.25% applied intracamerally causes toxic alteration of the human corneal endothelium. Methods In this prospective randomized masked study, 66 patients had cataract extraction using phacoemulsification, a frown incision, and implantation of a poly(methyl methacrylate) intraocular lens. This was followed by intraocular injection of 0.4 mL of cefotaxime 0.25% or balanced salt solution (BSS®). Contact specular microscopy and photography were performed preoperatively and 1 to 4 days and 3 months postoperatively. Results In the cefotaxime group, the mean endothelial cell count was 2729 cells/mm 2 ± 474 (SD) preoperatively, 2520 ± 462 cel…
Cystic vestibular schwannoma: classification, management, and facial nerve outcomes.
2009
OBJECTIVE: Review of postoperative morbidity and facial nerve outcomes of cystic vestibular schwannoma (CVS) patients compared with solid vestibular schwannoma (SVS) patients and a proposal for a new CVS classification system. STUDY DESIGN: Retrospective review. SETTING: Tertiary care facility. PATIENTS: Ninety-six patients with surgically treated CVS (1998-2008). Outcomes were assessed in a subpopulation of 57 patients with greater than or equal to 1-year follow-up compared with 57 SVS patients. INTERVENTION: Fifty-six CVS patients underwent the enlarged translabyrinthine approach with transapical extension (Type I), and 1 patient underwent a transcochlear/transzygomatic approach. MAIN OUT…
Corneal tattooing: an alternative treatment for disfiguring corneal scars.
2002
Background: The performance and results of corneal tattooing are described in a case series of 11 patients suffering from a disfiguring corneal scar using a technique similar to conventional dermatography. Methods: Drawing ink in different shades was applied into the anterior corneal stroma by punctures performed with a conventional spatula needle. Results: Up to 4 years after surgery all patients still had satisfactory staining of the formerly cosmetically disfiguring corneal scar. Conclusion: Tattooing of unsightly corneal scars proved to be an efficient and easy to perform technique, yielding acceptable results during follow up.
Changes in the anterior chamber during accommodation assessed with a Scheimpflug system.
2014
Purpose To study changes in the anterior chamber depth (ACD), anterior chamber angle, and pupil diameter with accommodation. Setting University of Valencia, Valencia, Spain. Design Evaluation of diagnostic technology. Methods A rotating Scheimpflug camera (Pentacam HR) was used to measure changes in the ACD, anterior chamber angle, and pupil diameter with accommodation. Peripheral ACD was measured at the corneal center and 2.0 mm away from it in the nasal, superior, temporal, and inferior directions. The anterior chamber angle was computed as the mean anterior chamber angle of the entire eye. All measurements were obtained with accommodation stimuli ranging from +1.0 to −4.0 diopters (D) in…
Predictive model to identify the risk of losing protective sensibility of the foot in patients with diabetes mellitus
2019
Diabetic neuropathy is defined as the presence of symptoms and signs of peripheral nerve dysfunction in diabetics. The aim of this study is to develop a predictive logistic model to identify the risk of losing protective sensitivity in the foot. This descriptive cross‐sectional study included 111 patients diagnosed with diabetes mellitus. Participants completed a questionnaire designed to evaluate neuropathic symptoms, and multivariate analysis was subsequently performed to identify an optimal predictive model. The explanatory capacity was evaluated by calculating the R (2) coefficient of Nagelkerke. Predictive capacity was evaluated by calculating sensitivity, specificity, and estimation o…
Differences in pitch between tones affect behaviour even when incorrectly identified in direction.
2001
The ability to detect differences between simultaneously presented contra- and ipsilesional stimuli but not to identify the former on neurological patients with the symptom termed 'extinction' has given rise to the hypothesis that extinguished stimuli have impaired access to attentive processing but are detected pre-attentively. Such a dissociation found in normal participants with experimentally degraded sensory information, and its absence in equivalent tasks in terms of the amount of information required has, however, led to an alternative hypothesis that the lesser amount of information required to perform same/different judgements is sufficient to explain this dissociation. In the pres…
Effects of transcranial direct current stimulation on esophageal motility in patients with gastroesophageal reflux disease
2014
To evaluate the effects of transcranial direct current stimulation (tDCS) on esophageal peristalsis in patients with gastroesophageal reflux disease (GERD).Patients with GERD preliminary diagnosis were included in a randomized double-blind sham-controlled study. Esophageal manometry was performed before and during transcranial direct current stimulation (tDCS) of the right precentral cortex. Half of patients were randomly assigned to anodal, half to sham stimulation. Distal waves amplitude and pathological waves percentage were measured, after swallowing water boli, for ten subsequent times. Last, a 24h pH-bilimetry was done to diagnose non-erosive reflux disease (NERD) or functional heartb…
Is somatosensory amplification a risk factor for an increased report of side effects? Reference data from the German general population
2015
Abstract Objective The study investigates the association between somatosensory amplification and the reporting of side effects. It establishes a German version of the Somatosensory Amplification Scale and examines its psychometric properties in a representative sample of the German population. Methods Sample size was 2.469, with 51% taking any medication. Participants answered the Somatosensory Amplification Scale, Generic Assessment of Side Effects Scale, and indicated whether they were taking any medication and the type of medication. Correlational analysis and binary logistic regression were performed. Results When examining a subsample reporting both medication intake and general bodil…