The purpose of this thesis is to describe the development of an anatomically based, young adult eye model, which includes a crystalline lens with a gradient refractive index (GRIN). This model will then be used to investigate the effect of laser refractive surgery. The first step in this process involved developing a symmetrical eye model that was found to be a better predictor of empirical lon...

PURPOSE To compare the astigmatic power of toric intraocular lenses (IOLs) obtained from the AcrySof, TECNIS, and iTrace toric calculator in patients with preoperative with-the-rule (WTR) or against-the-rule (ATR) corneal astigmatism. MATERIALS AND METHODS Fifty eyes with cataract and corneal astigmatism greater than 0.75 diopters were enrolled in each group (WTR and ATR). Keratometric values...

We read with interest the article by Tonn et al. on corneal astigmatism. At the beginning of the article, the authors indicated that: ‘‘Scheimpflug tomographers provide a map of the anterior chamber and therefore a more accurate model of the cornea, its thickness, and posterior surface.’’ Since the anterior chamber is really a space, and not a structure, it is probably clearer to say that Schei...

THiE problem of correcting the refractive error of an aphakic eye other than by prescribing the cumbersome cataract lenses still remains open, in spite of the excellent work done in this field by Ridley, and all its modifications. In search of a method which might combine greater safety for the patient with a simpler operative technique, an operation has been devised which consists in implantin...

BACKGROUND To determine the relationship between central corneal thickness (CCT), refractive error, corneal curvature, anterior chamber depth and axial length in normal Taiwanese Chinese adults. METHODS Five hundred normal Taiwanese Chinese patients aged 40-80 years were recruited for the study. Measurement procedures included CCT, refractive error, corneal curvature, anterior chamber depth a...

OCTOBER 2011 CATARACT & REFRACTIVE SURGERY TODAY EUROPE 31 A classic problem in cataract surgery is the a priori determination of the ideal power of the IOL to be implanted. After a long history of efforts by many practitioners and enthusiasts, current IOL power calculation methods provide reasonably good average accuracy. However, the price for this progress is an increasing number of formulas...

Corneal refractive surgery procedures are widely performed to permanently correct refractive errors. Overall, refractive surgeries are safe, predictable and present high rates of satisfaction. Nevertheless, the induced epithelial, stromal and nerve damage alters corneal integrity and function, triggering a regenerative response. Complications that arise from corneal wound healing process might ...