PURPOSE To investigate the change in visual acuity (VA) produced by different types of astigmatism (on the basis of the refractive power and position of the principal meridians) on normal accommodating eyes. METHODS The lens induced method was employed to simulate a set of 28 astigmatic blur conditions on different healthy emmetropic eyes. Additionally, 24 values of spherical defocus were als...

PURPOSE In eyes with a preoperative plano refractive cylinder, it would appear that there is no rationale for astigmatic treatment. The aim of this retrospective, cross-sectional data analysis was to determine the amount of topographic astigmatism in refractive plano eyes that results in reduced efficacy after myopic laser in situ keratomileusis (LASIK). METHODS This study included 267 eyes f...

AIM To compare the magnitude of apparent accommodation in pseudophakic eyes with refractive against-the-rule (ATR), with-the-rule (WTR) and minimum astigmatism. Factors associated with apparent accommodation were also examined in each group. METHODS In total, 87 pseudophakic eyes (87 patients) that underwent monofocal intraocular lens (IOL) implantation after uneventful cataract surgery were ...

PURPOSE To evaluate the effect of peripheral limbar relaxing incisions (PLRI) in the reduction of the astigmatism during cataract surgery. METHODS We studied prospectively 103 eyes of 103 patients submitted to PLRI, using the Nichamim nomogram during cataract surgery by phacoemulsification. After the first and sixth month we analized the changes in astigmatism topography, induction of astigma...

PURPOSE This study was conducted to compare post-operative astigmatic outcomes of two groups, with-the-rule (WTR) and against-the-rule (ATR) astigmatism patients, according to the haptic axis of intraocular lenses (IOLs) inserted in cataract surgery. METHODS Seventy-two eyes with WTR astigmatism and 79 eyes with ATR astigmatism had cataract surgery through a clear corneal temporal incision. T...

Acceptance for publication May’ 2011 .................................. Purpose: To compare surgically induced astigmatism between injector and forceps delivery system for intraocular lens implantation in phacoemulsification. Methods: This Quasi experimental study was carried out in Ophthalmology Department, Shaikh Zayed Hospital, Lahore. One hundred consecutive cataract patients were operated ...

To determine whether developing primate eyes are capable of growing in a manner that eliminates astigmatism, we reared infant monkeys with cylindrical spectacle lenses in front of one or both eyes that optically simulated with-the-rule, against-the-rule, or oblique astigmatism (+1.50-3.00x90, x180, x45 or x135). Refractive development was assessed by retinoscopy, keratometry and A-scan ultrason...

Modern cataract and refractive surgery aims not only to improve vision but to provide a good unaided visual acuity. Correcting astigmatic errors and control of surgically induced astigmatism are now an integral part of such operative procedures. Technological innovations and surgical developments in recent times have provided new methods for correction of astigmatism. However, evaluating the ou...

PURPOSE To measure the changes in astigmatism and in the degree of anisometropia when ametropes respond to accommodative stimulation. METHODS The accommodative responses of ametropes were binocularly measured with an improved photorefractometer (PR-1100), which objectively measured binocular refraction in all meridians simultaneously, when a visual fixation target was shown in natural space a...

The authors discussed about the problem of special form in astigmatism classification. This special type of astigmatism is the form of obliquely crossed astigmatism. In which the meridians, major and minor, are not right angles. In this astigmatism is not possible to prescribing for cylindrical (toric) spectacle lens. Authors describe the Thompson formula for oblique crossed cylinder and observ...