Short-Term Changes in Light Distortion in Orthokeratology Subjects

Purpose. Quantifying adaptation to light distortion of subjects undergoing orthokeratology (OK) for myopia during the first month of treatment. Methods. Twenty-nine healthy volunteers (age: 22.34 ± 8.08 years) with mean spherical equivalent refractive error −2.10 ± 0.93D were evaluated at baseline and days 1, 7, 15, and 30 of OK treatment. Light distortion was determined using an experimental prototype. Corneal aberrations were derived from corneal topography for different pupil sizes. Contrast sensitivity function (CSF) was analyzed for frequencies of 1.50, 2.12, 3.00, 4.24, 6.00, 8.49, 12.00, 16.97, and 24.00 cpd under photopic conditions. Results. Average monocular values of all light di…

Corrigendum to “Short-term changes in light distortion in orthokeratology subjects"

Artigo completo publicado na revista "BioMed Research International, (2015), 1-7" e disponível no RepositóriUM em: http://hdl.handle.net/1822/33375

Subjective Satisfaction in Long-term Orthokeratology Patients

Purpose: To AU3 evaluate the subjective satisfaction in visual stability, night vision complains, and light distortion phenomena, and also the number of hours and days per week of lens wear, in patients with myopia undergoing orthokeratology (OK) treatment for at least 1 year. Methods: A visual analog scale (VAS) questionnaire containing 18 items was administered to 44 patients, 29 women and 15 men (mean age, 24.39 6 9.11 years), with a baseline spherical equivalent refractive error of 22.40 6 0.94 diopters and astigmatism up to 20.5 diopters. Average treatment period by the time of data collection was 19 6 7 months. Patients rated their satisfaction with the correction, with complaints of …

Reliability of manual segmentation of cornea, contact lens and tear film using a high-resolution OCT

In this study, we aimed to evaluate the intra/inter-session and intra/inter-observer variability of manual segmentation of thickness of the pre-lens tear film, contact lens (CL), post-lens tear film, epithelium, bowman’s layer, stroma and the whole cornea and CLs with a flat and a steep fit, using a commercial high-resolution spectral domain optical coherence tomographer (OCT). Two different observers obtained three repeated measures in two separate sessions. A high correlation was found between the values obtained by the two different observers, except for the thinner layers, epithelium, and Bowman’s layer. Inter-observer analysis showed a high consistency in the measurements obtained by b…

Visual acuity changes in presbyopic patients fitted with 3 multifocal contact lenses

Technical note: a comparison of central and peripheral intraocular pressure using rebound tonometry

Purpose: To compare central and peripheral intraocular pressure (IOP) readings obtained with rebound tonometry.Methods: Intraocular pressure was measured on the right eye of 153 patients (65 males, 88 females), aged from 21 to 85 years (mean +/- S.D., 55.5 +/- 15.2 years) with the ICare rebound tonometer at centre, and 2 mm from the limbus (in the nasal and temporal regions along the 0-180O corneal meridian).Results: Intraocular pressure values obtained with the ICare were 14.9 +/- 2.8; 14.1 +/- 2.5 and 14.5 +/- 2.7 mmHg at centre, nasal and temporal corneal locations, respectively. On average, nasal and temporal IOP readings were 0.75 and 0.37 mmHg lower than the central reading (p 0.05, r…