الفهرس 
Chapter 1: Human CorneaOnly 14 pages are availabe for public view
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Abstract
Keratoconus is an ectatic corneal disorder characterized by a progressive corneal thinning that results in corneal protrusion, irregular astigmatism, and decreased vision.
Despite the good results of PK in keratoconus, there are reported complications such as allograft rejection, irregular astigmatism, side effects caused by long-term use of topical corticosteroids
Intrastromal corneal ring segments (ICRS) have been proposed as an additive surgical procedure for keratoconus by flattening the central cornea via an “arc‑shortening” effect on the corneal lamellae.
Implantation of a MyoRing through a corneal pocket is an alternative technique, has been described for use in the correction of keratoconus especially advanced cases. Channel creation for ICR can be done either by a manual technique or using a femtosecond laser.
Intrastromal implantation of KeraRing and MyoRing significantly improved UCVA and BCVA in patients with keratoconus and significantly decreased SE and keratometric values (Kmax) with early visual rehabilitation.
The visual and refractive results of femtosecond-assisted tunnel creation are comparable to those of manual tunnel creation. However, the femtosecond method is faster, easier, and more comfortable for both patient and surgeon.
Corneal collagen cross linking (CXL) can be combined after ICR implantation for stabilization of ectasia after regularization of the corneal surface.