Leber's Congenital Amaurosis
How is it diagnosed?
A diagnosis of LCA may be suspected on the basis of the typical clinical history and findings on eye examination but confirmation of the diagnosis relies on electrodiagnostic testing. A specific test, the electroretinogram (ERG) is performed. In this test electrodes are placed on the eyelids close to the eye and the tiny electrical signals generated by the eye in responses to light are recorded. In all forms of LCA the ERG is non–recordable or very poor. The ERG can help distinguish LCA from other retinal dystrophies that cause nystagmus in infancy such as achromatopsia and congenital stationary night blindness.
A minority of babies with the typical symptoms and signs of LCA may have other medical problems in early infancy such as developmental delay (see entry Global developmental delay) and other neurological signs and in such cases other conditions such as the peroxisomal disorders need to be excluded. A few children initially given the diagnostic label of LCA will later have a revised diagnosis if other medical problems develop with time. Features which may lead to a modified diagnosis include: kidney problems (Senior-Loken syndrome and Joubert syndrome see entry), heart problems, diabetes, hearing loss (Alström syndrome see entry), panting breathing pattern in infancy and later head shaking when using vision to track (Joubert syndrome).
LCA is a completely different condition from Leber's Hereditary Optic Neuropathy - the only connection being a description by the same doctor.
What are the causes?
| How is it treated? ![]()