Excimer laser correction of hyperopia, hyperopic and mixed astigmatism: past, present, and future.

The broad acceptance of "spot scanning" or "flying spot" excimer lasers in the last decade has enabled the domination of corneal ablative laser surgery over other refractive surgical procedures for the correction of hyperopia, hyperopic and mixed astigmatism. This review outlines the most important reasons why the ablative laser correction of hyperopia, hyperopic and mixed astigmatism for many years lagged behind that of myopia. Most of today's scanning laser systems, used in the LASIK and PRK procedures, can safely and effectively perform low, moderate and high hyperopic and hyperopic astigmatic corrections. The introduction of these laser platforms has also significantly improved the long term refractive stability of hyperopic treatments. In the future, further improvements in femtosecond and nanosecond technology, eye-tracker systems, and the development of new customized algorithms, such as the ray-tracing method, could additionally increase the upper limit for the safe and predictable corneal ablative laser correction ofhyperopia, hyperopic and mixed astigmatism.

Sunshine on holidays--eye risks.

Ultraviolet (UV) light is the most common cause of radiation injury to the eye which in acute exposure causes photokeratitis and photoconjunctivitis. After a whole day exposure to the sun on the Mediteranian coast patient presented with mixed conjunctival injection, chemosis, edematous corneal epithelium with superficially present fluoresceine positive small pinpoint defects. Epithelial bullous changes, circular stromal infiltration in the middle stromal perifery and reduction of corneal transparency were more pronounced on the left eye. After treatment moderate conjunctival injection remained together with circular stromal infiltration in the middle perifery, corneas were transparent, epithelialised and fluorescein negative. Anterior chambers and lenses were clear. One month after patient regained bilateral visual acuity of 1.0. To our kownledge, this case shows for the first time connection between acute ultraviolet radiation exposure and persistent circular stromal infiltration in the middle corneal perifery in humans.

Blue light filtering intraocular lenses in phacoemulsification cataract surgery.

Blue light can damage retina and cause age related macular degeneration. After cataract surgery and lens removal retina stays unprotected. Blue light filtering intraocular lenses (IOL) increase protection of the retina. In our prospective study we investigated clinical results after bilateral implantation of Acrysof Natural IOL to 30 patients (N = 60 eyes). In a control group (N = 60 eyes, 30 patients), standard acrysof IOL was implanted bilaterally. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA) and Nd YAG laser capsulotomy rate were measured and compared with control group. Subjective patient's satisfaction and subjective colour perception were also investigated. There was no significant difference in UCVA, BCVA and Nd YAG laser capsulotomy rate between the two groups. High patient's satisfaction was noticed (96.7% of patients would implant Acrysof Natural IOL again). Acrysof Natural IOL enables good visual acuity VA, low rate of Nd YAG laser capsulotomy and high patient's satisfaction without colour perception disturbances.