Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Leber's Congenital Amaurosis What is Leber's congenital amaurosis? What treatment is available? LCA is an inherited retinal degenerative disease characterized by severe loss of vision at birth. A variety of other eye-related abnormalities including roving eye movements, deepset eyes, and sensitivity to bright light also occur with this disease. LCA is an inherited disorder. It follows the autosomal recessive pattern of inheritance, which means that both parents must have a gene in order for their child to have the disorder. Some LCA types are progressive in that they become more severe with age and some are stationary in that there is little change noted with time. There is no cure for LCA. However, scientists have identified 14 genes with mutations that can each cause LCA. These genes account for approximately 75 percent of all cases of LCA. Researchers at Children's Hospital of Philadelphia and the University of Pennsylvania have treated six young people via gene therapy. Clinical trials of gene replacement therapy for LCA caused by mutations in the RPE65 are now beginning. It is the same therapy that gave vision to 50 dogs, including the world-famous Lancelot, born blind from LCA. Signs and symptoms Individuals with LCA have very reduced vision at birth. Within an infant’s first few months of life, parents usually notice a lack of visual responsiveness and unusual roving eye movements, known as nystagmus (roving eye). By early adolescence, various changes in the retinas of patients with LCA become readily apparent. Symptoms may include lens opacity (cataract), aversion to light (photophobia), hearing impairment and possibly developmental delays, keratoconus (cone shape to the front of the eye) and the oculo-digital reflex (repeated pressing of the eyes with the hands or fists) Diagnosis A key feature of LCA is an abnormally low electrical response of the retina. Retinal blood vessels can become thin and narrow and there can be pigmentary changes that an Ophthalmologist can see within the eye. This can be measured by using a method called Electroretinography. In this procedure, the retina is stimulated by light and the electrical response pattern is recorded on an electroretinogram (ERG) and compared with ERG responses from normal subjects. Sources: 1. http://www.tfrr.org/ 2. http://www.tsbvi.edu/Outreach/ seehear/spring01/lebers.htm 3. http://en.wikipedia.org/wiki/Leb er's_congenital_amaurosis 4. http://www.blindness.org/vision disorders/causes.asp?type=13 5. http://www.healthcentral.com/e ncyclopedia/408/468.html Leber's Congenital Amaurosis