Search results for "ocular"
showing 10 items of 1219 documents
In vivo definition of parieto-motor connections involved in planning of grasping movements
2010
We combined bifocal transcranial magnetic stimulation (TMS) and diffusion tensor imaging (DTI) tractography to investigate in humans the contribution of connections originating from different parietal areas in planning of different reaching to grasp movements. TMS experiments revealed that in the left hemisphere functional connectivity between the primary motor cortex (M1) and a portion of the angular gyrus (AG) close to the caudal intraparietal sulcus was activated during early preparation of reaching and grasping movements only when the movement was made with a whole hand grasp (WHG) towards objects in contralateral space. In contrast, a different pathway, linking M1 with a part of the su…
Effects of electrical stimulation in vestibular cortex areas in humans.
2010
The case of a patient with focal epilepsy is reported who underwent presurgical evaluation by stereotactic intracranial electroencephalographic (EEG) recording. A subdural semi-grid electrode, consisting of three multi-channel strip electrodes, was implanted over the temporal lobe and temporo-occipital region; one multi-channel depth electrode was applied towards the posterior insular cortex. During electrical stimulation and EEG monitoring eye movements were recorded by 3-D video-oculography. Stimulation of the medial temporal gyrus induced blurring of vision and horizontal nystagmus. Stimulation of the superior temporal gyrus with low intensities also induced blurring of vision and a simi…
Contrast sensitivity after refractive lens exchange with a multifocal diffractive aspheric intraocular lens
2013
Purpose: To evaluate distance and near contrast sensitivity (CS) under photopic and mesopic conditions before and after refractive lens exchange (RLE) and implantation of the aspheric AcrySof ReSTOR (SN6AD3 model) intraocular lens (IOL) Methods: Sixty eyes of 30 consecutive patients after RLE underwent bilateral implantation with the aspheric AcrySof ReSTOR IOL. The patients sample was divided into myopic [n=15, mean spherical equivalent (SE) -6.87± 2.03 diopters (D)] and hyperopic (n=15, mean SE +4.52±1.14 D) groups. Monocular uncorrected visual acuity at distance and near (UCVA and UCNVA, respectively) and monocular best corrected visual acuity at distance and near (BCVA and BCNVA, respec…
Mathematical Model Predicts Clinical Ocular Motor Syndromes
2003
: Clinical ocular motor syndromes were compared with ocular motor syndromes simulated by a mathematical model of the vestibuloocular reflex. The mathematical sensorimotor feedforward model of otolith control of three-dimensional binocular eye position is based on relevant anatomical connections of the vestibuloocular reflex from the utricles to extraocular eye muscles. This is the first attempt to simulate static ocular motor syndromes for unilateral utricular or vestibular nerve failure, lesions of the vestibular nucleus, and lesions of the ascending vestibuloocular reflex pathways. Comparison of the predicted syndromes with those found in patients with unilateral disorders of the vestibul…
Serum autoantibodies to alpha-fodrin are present in glaucoma patients from Germany and the United States.
2006
PURPOSE Glaucoma is characterized by a progressive loss of retinal ganglion cells that results in a characteristic optic neuropathy associated with visual field loss. In previous studies, changes in the antibody profiles have been shown in the sera of patients with glaucoma, and these findings suggest a role for autoimmune involvement in the pathogenesis of glaucoma in some patients. The purpose of this study was to compare the antibody profiles against optic nerve antigens in patients with glaucoma in two different study populations from Germany and the United States. METHODS One hundred twenty patients were included in the study, 60 from Germany and 60 from the United States: a control gr…
Perioperative pupil size in low-energy femtosecond laser-assisted cataract surgery
2020
Purpose To assess potential changes in pupil size during femtosecond laser-assisted cataract surgery (FLACS) using a low-energy laser system. Methods The pupil sizes of eyes undergoing FLACS were measured using the Ziemer LDV Z8 by extracting images from the laser software after each of the following steps: application of suction, lens fragmentation, and capsulotomy. Furthermore, the pupil diameters were measured based on preoperative surgical microscope images and after releasing the suction. Paired t-test and the two one-sided tests (TOST) procedure were used for statistical analyses. The horizontal and vertical pupil diameters were compared in each of the steps with preoperative values.…
Anisometropia of spherical equivalent and astigmatism among myopes: a 23-year follow-up study of prevalence and changes from childhood to adulthood.
2017
Purpose To study anisometropia of spherical equivalent and astigmatism from the onset of myopia at school age to adulthood. Methods A total of 240 myopic schoolchildren (mean age 10.9 years), with no previous spectacles, were recruited during 1983–1984 to a randomized 3-year clinical trial of bifocal treatment of myopia. Examinations with subjective cyclopedic refraction were repeated 3 years later (follow-up 1) for 238 subjects and thereafter at the mean ages of 23.2 (follow-up 2) and 33.9 years (follow-up 3) for 178 and 134 subjects. After exclusions, the 102 subjects who attended all three follow-ups were included in the analyses. Corneal refractive power and astigmatism and anterior cha…
Corneal thickness in children with growth hormone deficiency: The effect of GH treatment.
2014
Abstract OBJECTIVE: The eye represents a target site for GH action, although few data are available in patients with GH deficiency (GHD). Our aim was to evaluate central corneal thickness (CCT) and intraocular pressure (IOP) values in GHD children to assess the role played by GHD or GH treatment on these parameters. DESIGN: In 74 prepubertal GHD children (51M, 23F, aged 10.4±2.4years) we measured CCT and IOP before and after 12months of treatment. A baseline evaluation was also made in 50 healthy children matched for age, gender and body mass index. The study outcome considered CCT and IOP during treatment and their correlations with biochemical and auxological data. RESULTS: No difference …
The Role of Textured Material in Supporting Perceptual-Motor Functions
2013
Simple deformation of the skin surface with textured materials can improve human perceptual-motor performance. The implications of these findings are inexpensive, adaptable and easily integrated clothing, equipment and tools for improving perceptual-motor functionality. However, some clarification is needed because mixed results have been reported in the literature, highlighting positive, absent and/or negative effects of added texture on measures of perceptual-motor performance. Therefore the aim of this study was to evaluate the efficacy of textured materials for enhancing perceptual-motor functionality. The systematic review uncovered two variables suitable for sub-group analysis within …
An electrophysiological study of the ontogenesis of adenosine receptors in the CA1 area of rat hippocampus
1990
Abstract The depressant effect of adenosine (Ad) was studied electrophysiologically in hippocampal slices from 5-, 10-, 15-, 20-, 30- and 120-day-old rats. Ad (10μM) depressed the field EPSP in CA1 to the same extent in all age groups. Caffeine (Caf), an Ad receptor antagonist, enhanced and nitrobenzylthioinosine (NBI), an Ad uptake blocker, depressed the field EPSP. Both these effects were, however, less prominent in slices from younger animals, a finding consistent with lower extracellular levels of endogenous Ad in neonatal rats.