Vision Disorders
Benign And Malignant Tumors
Benign melanomas produce no symptoms and usually cause no loss of vision. Malignant melanomas of the choroid occur primarily around middle-age, producing symptoms similar to those caused by a detached retina—which can occur secondary to the tumor itself—and may result in spread of cancer to the bloodstream. When localized treatment with radiation therapy is not effective, the removal of the entire eye is recommended. Retinoblastoma usually affects children within the first two years of life, is closely related to astrocytoma—a tumor of the brain—and is the only primary tumor which occurs on the retina. It manifests as a "white pupil" or squint and if treatments with radiation therapy are ineffective, the affected eye is removed.
Additional topics
- Vision Disorders - Other Causes
- Vision Disorders - Fundus Inflammation And Tumors
- Other Free Encyclopedias
Science EncyclopediaScience & Philosophy: Verbena Family (Verbenaceae) - Tropical Hardwoods In The Verbena Family to WelfarismVision Disorders - Refractive Errors, Hyperopia/presbyopia, Other Refractive Errors, Strabismus, Nonparalytic Strabismus, Paralytic Strabismus - Myopia, Astigmatism, Glaucoma, Secondary glaucomas, Degeneration of the macula, Retinal dystrophies