PURPOSE To determine the distribution of Zernike coefficients and higher order aberrations in a normal population and its relationship with age, gender, biometric components, and spherical equivalent. METHODS During the first phase of the Shahroud cohort study, 6311 people of the 40-64-year-old population of Shahroud city were selected through random cluster sampling. A subsample of participa...

AIM To study the distribution of ocular higher-order aberrations(HOAs) and mesopic pupil size in individuals screened for refractive surgery. METHODS Ocular HOAs and mesopic pupil size were studied in 2 458 eyes of 1 240 patients with myopia, myopic astigmatism and compound myopic astigmatism and 215 eyes of 110 patients with hyperopia, hyperopic astigmatism and compound hyperopic astigmatism...

PURPOSE Corneal biomechanical properties are usually measured by strip extensiometry or inflation methods. We developed a two-dimensional (2D) flap extensiometry technique, combining the advantages of both methods, and applied it to measure the effect of UV-Riboflavin cross-linking (CXL). METHODS Corneal flaps (13 pig/8 rabbit) from the de-epithelialized anterior stroma (96 μm) were mounted o...

PURPOSE To compare the astigmatism, high order aberrations, and optical quality of the cornea after microincision (approximately 1.7 mm) versus small incision approximately 3.2 mm) cataract surgery at Eye Center, Zhejiang University, Hangzhou, China. METHODS This prospective, randomized clinical study included microincision cataract surgery and small incision cataract surgery performed on 60 ...

PURPOSE To analyze results of wavefront-guided laser vision correction retreatments performed either by lifting the original flap or by surface ablation over the flap. SETTING Optical Express, Glasgow, United Kingdom. DESIGN Retrospective case series. METHODS This retrospective study included patients grouped according to whether they had flap lift enhancement or photorefractive keratecto...

PURPOSE To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia. METHODS The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia...

PURPOSE To compare the contributions of single vision (SVCL) and multifocal contact lenses (MFCL) to the relative peripheral refraction (RPR) profiles obtained via an autorefractor and an aberrometer in a pilot study. METHODS Two instruments, Shin-Nippon NVision K5001 (SN) and COAS-HD, were modified to permit open field PR measurements. Two myopic adults (CF, RB) were refracted (cycloplegia) ...

O ptometry has a history of taking the lead in correcting the optical defects of the eye. While the primary definition of optometry has changed as the profession has expanded its scope of practice, the secondary definition of optometry has remained unchanged. The second definition of optometry is the use of an optometer. The definition of optometer is any of several objective or subjective devi...

PURPOSE To evaluate the objective accommodative response, change of aberrations, and depth of focus in eyes implanted with the Crystalens accommodative intraocular lens (IOL) at different accommodative demands. DESIGN Prospective, observational study. METHODS Eleven cataract patients (22 eyes) who underwent implantation of a Crystalens accommodative IOL, and control groups of 9 normal subje...

A NEW upgrade to the Zyoptix wavefrontguided refractive surgery system (Bausch&Lomb) greatly simplifies preoperative examination and calculation of the ablation profile by removing the need for pupil dilatation during aberrometry and automatically incorporating wavefront data in the treatment algorithm, said Erik Mertens MD,Antwerp Eye Center,Antwerp, Belgium. The upgrades include a better comp...