الفهرس 
Anatomy of the corneaOnly 14 pages are availabe for public view
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Abstract
LASIK done under topical anaesthesia and require proper preoperative instrument setup then performing the keratectomy, laser ablation then reposition the flap.
Incisional wound healing start with the formation of fibrin plug in the wound cleft which is replaced in a few days by invaginating epithelial cells. Some stromal nerve within the flap show degenerative changes , but circumferentially located regenerative nerves are formed at the flap margins. The epithelial innervation is restorted several months after LASIK.
LASIK affect the tear film leading to dry eye syndrome, fluctuating vision and mild to severe punctuate erosion with decreased tear secretion and stability . Dry eye after LASIK due to corneal denervation caused by the cutting of the corneal nerve. Altered corneal contour may leads to this problem .It is still somewhat unclear if there is long –term reduction in tear production in all patients who undergo LASIK.
Epithelial defect is an operative complication in LASIK. The squelae of such defects lead to achievement of the desired visual acuity, may lead to recurrent erosion syndrome, diffuse lamellar keratitis, microbial keratitis and epithelial ingrowth.
The epithelium showes a tendency towards the hyperplasia starting from the first day reaching the maximum thickness between the 1st , 3rd month after LASIK leading to regression of the refractive effect.
Ectopic epithelial growing within the LASIK lamellar interface can produce significant morbidity, leads to forign body sensation, decreased best-corrected visual acuity, astigmatism, night glare.
Keratectasia occurs in patients who are predisposed to this due to abnormal topography or excessively thin corneas, or in patients in whom inadequate posterior corneal tissue is preserved.
Further work is required to understand which types of patients are predisposed to developing keratectasia, but this clearly is an achievable goal.
Microbial keratitis occurs because of intraoperative introduction of organisms into the lamellar interface. Introduction of laser devices to make lamellar flaps will reduce the amount of instrumentation that is required and should minimize this risk. If technology permits the development of intrastromal keratomileusis, then tissue can be ablated without the creation of a lamellar flap, which should completely eliminate the risk of microbial keratitis
LASIK is currently essential tool for the correction of a wide range of refractive errors. New advances offer the promise of improved safety, enhanced postoperatively quality of vision and the opportunity for life long adjustment of refractive errors and ocular aberrations.
Most of the corneal changes after LASIK can be avoided by perfect maneuvre, skilful surgeon and good selection of the patients to whom the LASIK surgery is performed.