purpose: to evaluate the safety, efficacy, stability and predictability of posterior chamber collagen copolymer phakic intraocular lens (piol) implantation to correct myopia and myopic astigmatism in keratoconus-affected patients. methods: uncorrected (ucva) and best-corrected (bcva) distance visual acuity, refraction and complications were evaluated in 22 keratoconic eyes of 14 patients who un...

purpose: to compare visual outcomes and surgical complications of three phakic intraocular lenses (piols); artisan, artiflex and the implantable collamer lens (icl) for correction of moderate to high myopia. methods: in this historical cohort study, 112 myopic eyes that were operated between 2005 and 2010 and implanted with one of these three piols were evaluated (artisan 40 eyes, artiflex 36 e...

PURPOSE Some debate surrounds the accommodative mechanism in primates, particularly whether the lens equatorial diameter increases or decreases during accommodation. This study has been undertaken to measure the relationship between changes in lens diameter and refraction during accommodation in rhesus monkeys. METHODS Photorefraction was used to measure accommodation, and goniovideography wa...

purpose: to evaluate visual function in patients with different types of light-filtering intraocular lenses (iols) methods: in this prospective comparative clinical study cataract patients with different types of iols in khatam-al-anbia eye hospital, mashhad were enrolled and followed for three months postoperatively. corrected distance visual acuity (cdva), color discrimination under photopic ...

Mechanical interaction between aqueous humor, iris, and intraocular structures can alter the iris profile from its normal curvature. In particular, significant changes to the iris profile occur during accommodation as the anterior lens movement forces the iris into greater posterior bowing. We extended a previous mathematical model of the anterior segment and investigated the response of this c...

Observation of the naturally-occurring accommodative response of a highly visual teleost species provides the opportunity to study its stimulus-response accuracy. A video recording system, linked to a computer digitizing program, was used to measure accommodative changes in lens position in the oscar, Astronotus ocellatus, in response to known food stimuli. The largest lens deviations occurred ...

It is well known that the crystalline lens (henceforth lens) can oscillate (or 'wobble') relative to the eyeball at the end of saccades. Recent research has proposed that such wobbling of the lens is a source of post-saccadic oscillations (PSOs) seen in data recorded by eye trackers that estimate gaze direction from the location of the pupil. Since the size of the lens wobbles increases with ac...

PURPOSE To evaluate changes in the peripheral refraction (PR), visual quality, and accommodative lag with a novel soft radial refractive gradient (SRRG) experimental contact lens that produces peripheral myopic defocus. METHODS 59 myopic right eyes were fitted with the lens. The PR was measured up to 30° in the nasal and temporal horizontal visual fields and compared with values obtained with...

PURPOSE Our purpose was to evaluate the long-term visual outcomes after bilateral implantation of Crystalens(®) HD (Bausch and Lomb, Inc.) accommodative intraocular lenses. METHODS In this study, 25 patients (50 eyes) who underwent cataract surgery and bilateral Crystalens HD accommodative intraocular lens implantation were included. The Crystalens HD lens was implanted in the bag in both eye...