Earlier experiments suggest that the perception of relative and absolute distance in binocular space is affected by the convergence angle to the stimulus. The question is how? A hypothesis was proposed in which the obtained effects are accounted for in terms of convergence differences. The hypothesis states that binocular stimuli are related to the rest convergence of the eyes which is assumed ...

PURPOSE To describe the incidence, timing, visual significance, and management of posterior segment complications after Boston type I keratoprosthesis implantation. METHODS A retrospective chart review was conducted of all consecutive Boston type I keratoprostheses implanted by a single surgeon at a single institution over a 6-year period. Preoperative demographics, postoperative complication...

PURPOSE To determine the effect of axis orientation on visual performance in astigmatic eyes. SETTING Department of Ophthalmology, Kitasato University, Kanagawa, Japan. DESIGN Investigational simulation. METHODS Healthy volunteers with no ophthalmic disease other than refractive errors were enrolled. After cycloplegic refraction was fully corrected with a 3.0 mm artificial pupil, with-the...

Roadsides are preferential migration corridors for invasive plant species and can act as starting points for plant invasions into adjacent habitats. Rapid spread and interrupted distribution patterns of introduced plant species indicate long-distance dispersal along roads. The extent to which this process is due to species' migration along linear habitats or, alternatively, to seed transport by...

Stereopsis is the ability to estimate distance based on the different views seen in the two eyes [1-5]. It is an important model perceptual system in neuroscience and a major area of machine vision. Mammalian, avian, and almost all machine stereo algorithms look for similarities between the luminance-defined images in the two eyes, using a series of computations to produce a map showing how dep...

-------------------------------------------------------------------ABSTRACT--------------------------------------------------------------Glaucoma is a disease associated with human eyes and second conducting movementofblindness across the globe if eyes are not treated at preliminary stage. Glaucoma normally occurs with increased intra-ocular pressure (IOP) in eyes and gradually damagesthe visio...

PURPOSE To study the evolution of visual and refractive outcomes through the first year after simultaneous topography-guided photorefractive keratectomy (t-PRK) and corneal collagen cross-linking (CXL) in keratoconus. METHODS This retrospective case series included 85 eyes of 66 patients with a mean age of 26.3 ± 5.7 years, which underwent simultaneous t-PRK with accelerated CXL. Patients wer...

As we move through the world, our eyes acquire a sequence of images. The information from this sequence is sufficient to determine the structure of a three-dimensional scene, up to a scale factor determined by the distance that the eyes have moved. Previous evidence shows that the human visual system accounts for the distance the observer has walked and the separation of the eyes when judging t...

Most of the time, the human visual system computes perceived size by scaling the size of an object on the retina with its perceived distance. There are instances, however, in which size-distance scaling is not based on visual inputs but on extraretinal cues. In the Taylor illusion, the perceived afterimage that is projected on an observer's hand will change in size depending on how far the limb...

Purpose: The objective of this study was to evaluate the outcome of Acrysof Toric intraocular lenses (IOLs) implantation in cataract surgery for the correction of regular corneal astigmatism. Methods: Twenty eyes of 16 patients with cataract and regular corneal astigmatism of 1.00-4.00 diopter (D) underwent surgery. Depending on the amount of corneal astigmatism, an Acrysof Toric IOL of type SN...