Search results for "Organs"
showing 10 items of 2730 documents
Aging Affects the Mental Rotation of Left and Right Hands
2009
BACKGROUND:Normal aging significantly influences motor and cognitive performance. Little is known about age-related changes in action simulation. Here, we investigated the influence of aging on implicit motor imagery. METHODOLOGY/PRINCIPAL FINDINGS:Twenty young (mean age: 23.9+/-2.8 years) and nineteen elderly (mean age: 78.3+/-4.5 years) subjects, all right-handed, were required to determine the laterality of hands presented in various positions. To do so, they mentally rotated their hands to match them with the hand-stimuli. We showed that: (1) elderly subjects were affected in their ability to implicitly simulate movements of the upper limbs, especially those requiring the largest amplit…
Light distortion of soft multifocal contact lenses with different pupil size and shape
2020
Purpose: To study the light distortion effects of soft multifocal contact lenses and the influence of different pupil size and shape.Methods: A total of 14 eyes of 7 healthy contact lens users (mean age 28.6 +/- 8.5 years) were recruited. The "Light Disturbance Analyser" device was employed for light characterization. The selected lenses were the monthly disposable "Biofinity multifocal" (CooperVision, CA, USA), both centre-distance and centre-near designs (addition power + 2.50 D). Two circular pupils of 3 mm and 5 mm of diameter, and an elliptical shape (3 horizontal and 5 vertical mm) were used. Metrics such as the light distortion index (LDI), best-fit circle radius and its irregularity…
A method for determining precise electrical hearing thresholds in cochlear implant users
2018
A psychoacoustic procedure designed for the precise assessment of perceptional threshold (T-level) in cochlear implant (CI) users is presented. The impact of this procedure on speech perception was investigated.Individual T-level measurements were obtained with the proposed procedure and three different speech processor fitting conditions were applied: (1) fitting familiar to the subject, T-levels unchanged, (2) T-level set to thresholds determined with the new procedure, (3) T-level set to thresholds determined with the new procedure, but T-level is decreased by 10 clinical units (CU). The impact of the different fitting conditions was measured by means of categorical loudness scaling (CLS…
An Emerging Method to Assess Tear Film Spread and Dynamics as Possible Tear Film Homeostasis Markers
2021
This study aims to assess the performance of an analysis method to measure in vivo the movement speed of tear film particles post-blink as a measure of tear film spreading. Ocular surface parameter...
Medial Vestibular Nucleus Lesions in Wallenberg's Syndrome Cause Decreased Activity of the Contralateral Vestibular Cortex
2005
Three patients with the clinical diagnosis of Wallenberg's syndrome caused by acute unilateral ischemic infarctions, which included the vestibular nucleus in the medullary brain stem and afferent vestibular pathways, were examined by positron emission tomography (PET) during caloric vestibular stimulation. They all had typical signs of vestibular dysfunction such as transient rotatory vertigo with vomiting at the onset, ipsiversive body and ocular lateropulsion, and a complete ocular tilt reaction with tilts of the subjective visual vertical. Compared with healthy volunteers, who show activation in a network of temporoparietal vestibular areas within both hemispheres, especially in the post…
Optical coherence tomography of macular thickness after biaxial vs coaxial microincision clear corneal cataract surgery
2009
PURPOSE To evaluate macular thickness changes after biaxial microincision versus coaxial small incision cataract surgery using optical coherence tomography (OCT). METHODS This prospective, randomized, marked study comprised 70 patients (70 eyes) undergoing biaxial microincision surgery or conventional coaxial phacoemulsification. Patients were evaluated by Stratus OCT preoperatively and 1 day, 4 weeks, and 8 weeks postoperatively. Best-corrected visual acuity (BCVA), phacoemulsification power, and effective phacoemulsification time (EPT) were evaluated. RESULTS In the biaxial group, median foveal thickness changed from 160 microm preoperatively to 168 microm 8 weeks postoperatively (p=0.018…
Incidence of posterior vitreous detachment after cataract surgery
2009
Purpose To report the incidence of posterior vitreous detachment (PVD) after uneventful state-of-the-art small-incision phacoemulsification with implantation of a posterior chamber intraocular lens (PC IOL). Setting Department of Ophthalmology, Ludwigshafen Hospital, Ludwigshafen, Germany. Methods This prospective study evaluated the vitreous status of eyes by biomicroscopic examination, indirect binocular ophthalmoscopy, and B-scan ultrasonography before planned cataract surgery. Patients with the posterior vitreous attached were included for follow-up and examined 1 week, 1 month, and 1 year after uneventful phacoemulsification with PC IOL implantation. The preoperative prevalence and pos…
Visual cortex hyperexcitability in migraine in response to sound-induced flash illusions
2015
Objective: Sound-induced flash illusions depend on visual cortical excitability. In this study, we explored whether sound-induced flash illusions are perceived differently in migraine, a condition associated with pathologic cortical hyperexcitability. Methods: Sound-induced flash illusions were examined in 59 migraine patients (mean age = 32 ± 16 years; 36 females), 32 without aura and 27 with aura, and in 24 healthy controls (mean age = 42 ± 17 years; 16 females). Patients were studied during attacks and interictally. Visual stimuli (flashes) accompanied by sounds (beeps) were presented in different combinations: a single flash with multiple beeps was given to induce the perception of mult…
Soft tissue pathosis associated with asymptomatic impacted lower third molars
2010
Objective: The aim of this study was to identify the prevalence of pathological changes in the pericoronal tissue of asymptomatic impacted lower third molars and to assess the correlation between pathological changes and patient demographic, radiographic and morphological characteristics. Study Design: Follicles associated with fully impacted lower third molars were submitted for histological examiDesign: Follicles associated with fully impacted lower third molars were submitted for histological examiesign: Follicles associated with fully impacted lower third molars were submitted for histological examination after surgical extraction from 50 patients. The correlation between pathological c…
Cachexia induces head and neck changes in locally advanced oropharyngeal carcinoma during definitive cisplatin and image-guided volumetric-modulated …
2015
Cancer cachexia is a syndrome characterized by weight loss (WL) and sarcopenia. Aim of the study was to assess the impact of cachexia on head and neck changes during definitive cisplatin and image-guided volumetric-modulated arc radiation therapy in a series of locally advanced oropharyngeal cancer.Volume variations of sternocleidomastoid muscle (SCM) were considered as surrogate of muscle changes related to sarcopenia. Two head and neck diameters, encompassing the cranial limits of II and III nodal levels (defined as 'head diameter' and 'neck diameter', respectively), were measured. All parameters were defined retrospectively by means of on-board cone beam computed tomography images at 1-8…