الفهرس 
Anatomy and Embryology of the CorneaOnly 14 pages are availabe for public view
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Abstract
T
he corea is a transparent avascular highly sensitive structure, which covers the anterior 1/6 of the outer coat of the human eye.
Its development starts very early in pregnancy. It reaches the adult strucyure and dimensions in a full-term baby.
Anatomically, it’s elliptical in shape thinner in the center than the periphery.
Microscopically, it’s formed of 6 layers.The epithelium is formed by 3 types of cells, which are undergoing mitosis.The surface layer contains microvilli covered by glycocalyx that interact with mucin layer of the tear film to keep a smooth regular optical surface. Bowman’s and descment’s membranes are both acellular, non-regenerating basement membranes.
The stroma constitutes 80% of the corneal structure. Dua layer is the lastest discovered tough strong layer. The endothelium is the inner important layer, which maintain the corneal hydration and transparency by its main vital barrier function. This is achieved with number of channels and pumps by the help of co-transporters across the strong cell junctions.
Cataract is a cloudy area in the eye lens. Most cataract surgeries are done using topical anesthesia. Phacoemulsification is the most common surgery used nowadays due to its better results in healing and post-operative vision quality.
IP is a newer technique than traditional longitudinal phaco. It reduses the risk of post-occlusion surge due to lens material reposition and more effective in harder cataracts.
Pre-operative corneal endothelium assessment is important to judge the extent of damage occurs, as it is a common complication. TASS occurs due to loss of endothelial barrier function and hence, corneal decompensation.
Long phaco time in hard cataracts in old aged patients lead to usage of higher energy, fuch’s dystrophy, pseudoexfoliation, and post-operative increase of IOP due to retention of the OVDs in the anterior champer are the most common causes of endothelial damage.
In the future, cataract surgeries will achieve more progress by using laser instead of ultrasound to lessen endothelial exposure to high energy and damage. This also will make the incision needed for IOL implantation smaller than 0.7 mm, which gurantee better post-operative vision quality than nowadays.