Ad
related to: what is pigmentation glaucoma disease definition medical dictionary chart
Search results
Results From The WOW.Com Content Network
Pigment dispersion syndrome (PDS) is an eye disorder that can lead to a form of glaucoma known as pigmentary glaucoma. It takes place when pigment cells slough off from the back of the iris and float around in the aqueous humor .
The disease is caused by an increase of melanocytes in the iris, choroid, and surrounding structures. Overproduction of pigment by these cells can block the trabecular meshwork through which fluid drains from the eye. The increased fluid in the eye leads to increased pressure, which can lead to glaucoma.
There is no evidence for changes in the iris pattern other than variations in pigmentation in the first years of life and variations caused by glaucoma treatment. The stability of iris structures is the foundation of the biometric technology which uses iris recognition for identification purposes.
It is associated with old age, a family history of glaucoma, and certain medical conditions or the use of some medications. [6] The word glaucoma comes from the Ancient Greek word γλαυκός (glaukós), meaning 'gleaming, blue-green, gray'. Of the different types of glaucoma, the most common are called open-angle glaucoma and closed-angle ...
Skin pigmentation is frequently caused by sun exposure. To protect itself against UV radiation from the sun, the body makes more melanin. As a result, the skin may become more pigmented to protect it from the sun's rays. [4] The pigmentation of the skin may also be lightened by certain drugs.
Heterochromia is a variation in coloration most often used to describe color differences of the iris, but can also be applied to color variation of hair [1] or skin. Heterochromia is determined by the production, delivery, and concentration of melanin (a pigment). It may be inherited, or caused by genetic mosaicism, chimerism, disease, or ...
Pigmentary changes in the retina – In addition to the pigmented cells in the iris (the colored part of the eye), there are pigmented cells beneath the retina. As these cells break down and release their pigment, dark clumps of released pigment and later, areas that are less pigmented may appear [citation needed]
Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is an acquired inflammatory uveitis that belongs to the heterogenous group of white dot syndromes in which light-coloured (yellowish-white) lesions begin to form in the macular area of the retina.