الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Photoablation is the use of laser light to transform corneal tissue by breaking carbon-to carbon bonds into a gaseous state . These gases are then ejected from the corneal surface. The most striking feature of excimer induced incisions are the sharp definition and absolute parallel appearance of the edges of the ablated areas at 193 nm. LASIK is a promising technique for the correction of low,moderate and high myopia, hyperopia and astigmatism. LASIK is a technique combining the advantage of lamellar corneal surgery (not disturbing bowman’s layer) with the precision of eximer laser surgery. Micro keratome or femto second laser are used to create a large central corneal flap , the excimer laser is used in the bed of the flap to remove a specific amount of stromal tissue, after which the flap is replaced in its original position. Fortunately, loss of best corrected visual acuity (BCVA) is rare, and the incidence of adverse events fall as the surgeon gains experience with the procedure. The development of more reliable microkeratome and improvements in laser technology should improve the future outcome of LASIK. Preoperative patient education and understanding of the advantages and disadvantages, as well as realistic expectation, are a cornerstone to successful management of these refractive surgery patients. Much of the success of LASIK surgery is attributed to the relatively few complications that may occur postoperatively. These complications may range in severity from insignificant as irrigular flap,decentered flap, uneven ablation, pain to catastrophic as corneal perforation , stromal melting, flap destruction. Resulting in irreversible visual loss and/or further surgical intervention; therefore, careful follow-up to ensure early detection is very important in postoperative management of patients undergoing LASIK surgery. Patients should be informed that many times a second operation or enhancement procedure is required. the potential complications of LASIK may be classified in to intraoperative or post operative complications: Intraoperative complications may be Flap related as buttonhole which could be managed by avoiding laser and replace flap pieces as best as you can then place aBSCL then redo laser 2-3months later with athicker plate,corneal perforation which could be managed by turning off suction and terminating the procedure then immediate closure of corneal wound and placing an ocular protective shield. Hinge related complications as Absent hinge(Free cap) in which management depends on its size and centration if as large as the laser treatment zone and centered the laser treatment may be safely performed. laser related complications as decentration which could be managed by trans epithelial ablation opposite to the decentered ablation and customized ablation. Intra operative complications with femto second laser as anterior chamber gas bubbles, opaque bubble layer,epithelial gas breakthrough. Postoperative complications which may be divided into: * Early postoperative complications (24-48 hours) as: Infection which could be managed aggressively by broad spectrum antibiotics , DLK which could be managed by potent DROPs of topical steroids with prophylactic antibiotic cover. * Late postoperative complications as: Epithelial ingrowth which could be managed by surgical debridement and if recurrent could be managed by suturing the flap. Errors in refractive predictability (undercorrection, overcorrection, astigmatism) which could be managed either non surgically by glasses and contact lenses lenses or surgically. Keratectasia in which conservative management by RGPCL is the first line of treatement . Dry eye which could be managed by surface lubricants,punctual plugs and cyclosporine DROPs.