Many animals rely on path integration for navigation and desert ants are the champions. On leaving the nest, ants continuously integrate their distance and direction of travel so that they always know their current distance and direction from the nest and can take a direct path to home. Distance information originates from a step-counter and directional information is based on a celestial compa...

purpose : to assess the visual and refractive outcomes after implantation of toric implantable collamer lens (t-icl) in compound myopic astigmatism methods : in this prospective study, 28 eyes with manifest refraction spherical equivalent (mrse) errors of -10.94±4.09 diopter (d) and mean cylindrical errors of -3.47±1.39 d underwent t-icl implantation. six months after surgery, best corrected an...

Two triangulation methods for measuring perceived egocentric distance were examined. In the triangulation-by-pointing procedure, the observer views a target at some distance and, with eyes closed, attempts to point continuously at the target while traversing a path that passes by it. In the triangulation-by-walking procedure, the observer views a target and, with eyes closed, traverses a path t...

PURPOSE To measure the MRD (margin reflex distance) in rigid contact lens wearers and controls by a new method, based on computerized image processing. METHOD The patients were selected from the Contact Lens Sector of the Ophthalmology Service at the "Complexo Hospitalar Santa Casa de Porto Alegre", and they were divided into two groups: the first was formed of rigid contact lens wearers (63 ...

The goal of the study was to test the quality of binocular coordination of saccades in children and adults, and its dependency upon the viewing distance. Fourteen normal children (4.5-12 years old) and 10 normal adults (22-44 years old) participated. Two distances were studied: far (150 cm) and close (20 cm). Horizontal saccades from both eyes were recorded simultaneously by a photoelectric dev...

PURPOSE To evaluate the relative effectiveness and safety of LASIK using the Femto LDV (Ziemer Ophthalmic Systems AG) and IntraLase FS 60 (Abbott Medical Optics Inc) femtosecond lasers in patients with corneal opacity. METHODS Patients with corneal opacity were retrospectively selected between March and July 2009. For this study, 205 eyes with 90-μm corneal flaps created using the Femto LDV (...

PURPOSE To compare the visual acuity and contrast sensitivity in eyes with the AcrySof ReSTOR multifocal intraocular lens (IOL) (Alcon) and eyes with the monofocal AcrySof SA60AT IOL. SETTING Policlinico Umberto I, Department of Ophthalmology, Rome, and private clinical practice, Rome, Italy. METHODS One hundred eyes had phacoemulsification cataract extraction and implantation of a ReSTOR m...

Purpose: To evaluate the safety, efficacy, predictability and stability for a cohort of myopic eyes treated by Femtosecond-LASIK procedure. Methods: 60 eyes (36 patients) with different degrees of myopia that underwent refractive surgery by using the Femtosecond-LASIK technique were prospectively evaluated for 12 months. The mean preoperative spherical equivalent value was -3.827 ± 1.410 diopte...

We prospectively compared visual and refractive outcomes in patients with high myopia and myopic astigmatism after small-incision lenticule extraction (SMILE) and photorefractive keratetctomy (PRK) with mitomycin C. Sixty-six eyes of 33 patients (mean age, 29.7 ± 5.6 years) were included (SMILE: 34 eyes, PRK 32 eyes). Preoperatively, no significant difference was noted in manifest spherical equ...