الفهرس | Only 14 pages are availabe for public view |
Abstract Many patients, especially those with lower to moderate levels of myopia, are candidates for either LASIK or PRK procedures. Although patients of LASIK group clearly benefit from a more rapid recovery of functional visual acuity, they also must incur the risk of flap complications that could have long term implications for visual performance. It is important to provide objective information regarding the difference in visual recovery between the two procedures because this is one of the primary criteria that patients use in making an informed decision. These two procedures are safe, predictable and present high rates of satisfaction. However, 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 directly impact on visual outcomes of keratorefricative procedures and may cause myopic regression as a result. The overall positive benefits of laser refractive procedures heavily outweigh the negative associations with visual regression. For example, younger patients with mild to moderate myopic errors may never experience regression significant enough to warrant enhancement. Nevertheless, regression after refractive surgery remains a limiting factor to the long term effectiveness of these procedures, especially in patients with large refractive errors or hyperopia. For most patients in developed countries, the prospect of a re-enhancement procedure or possibly returning to glasses generally does not prevent undergoing LASIK, PRK. Currently, there are no modalities or pharmacological agents that can effectively prevent refractive regression in all patients. Ultimately, refractive regression is a multifactorial process that can vary between individuals, and future efforts towards its prevention should be directed at developing a more complete view of the risk factors and mechanisms of the said regression. |