الفهرس | Only 14 pages are availabe for public view |
Abstract With advancing age, the normal function of eye tissues decreases and there is an increased incidence of ocular pathology. Senile changes of the eyelids include: blepharochalasis,relaxation of tarsal ligaments,tarsi and orbital septum may show defects through which orbital fat may prolapse. There are correlations between age and diffuse fibrosis, diffuse atrophy, and periductal fibrosis in the lacrimal gland. Diffuse fibrosis and diffuse atrophy in orbital lobes were more frequently observed in women than in men. There is a relationship between the anteroplacement of the mucocutaneous junction and the conjunctivochalasis with aging. Dry eye or keratoconjunctivitis sicca (KCS), is a chronic and sometimes debilitating condition resulting from tear film dysfunction. Arcus senilis is the most common of all senile changes in the cornea. A condition called crocodile shagreen may appear clinically. Reduction in keratocyte and endothelial cell density with increasing subject age occurs. Interestingly, corneal sub-basal nerve fiber density also significantly decreases with increasing age. Aging is accompanied by three main changes in the lens: nuclear discoloration, increased light scatter mainly in the nucleus and occurrence of cortical opacities. With aging, the human lens exhibits increased aggregation of the lensstructural proteins and an increasing amount of water-insoluble protein upon homogenization. Several laboratories have implicated the formation of advanced glycation endproducts (AGEs) as being responsible for the bulk of these protein modifications. |