What type of nystagmus is seen in albinism?
Nystagmus associated with albinism is the result of multifactorial visual impairment. Anatomical findings include abnormal ocular pigmentation, foveal hypoplasia, abnormally increased chiasmal decussation, and high cylindrical refractive errors. Several subtypes have been described.
What is the difference between OCA1 and OCA2?
This type of OCA1 is called OCA1B. In the case of OCA1B, melanin pigment will accumulate with time in the skin, hair and eyes. Oculocutaneous albinism type II (OCA2) is associated with the same vision problems that occur in OCA1.
What is congenital pendular nystagmus?
Pendular nystagmus is a sinusoidal oscillation. The waveform of pendular nystagmus may occur in any direction; it can be torsional, horizontal, vertical, or a combination of these, resulting in circular, oblique, or elliptical trajectories. It may be different in the two eyes, sometimes even monocular.
What is the difference between ocular albinism and oculocutaneous albinism?
Ocular albinism can occur clinically in several forms. If only the eyes are involved, it is termed ocular albinism, which is most frequently inherited as X-linked recessive. If both the skin and the eyes are affected, it is referred to as oculocutaneous albinism (OC albinism).
Do people with albinism have nystagmus?
Several vision problems can occur with ocular albinism including an involuntary movement of eyes back and forth (nystagmus), reduced iris pigment in some individuals, reduced retinal pigment, lack of development of the fovea (foveal hypoplasia) leading to blurred vision, and abnormal connections in the nerves from the …
Why do albino people’s eyes shake?
Nystagmus (the back and forth movement of the eyes) as well as the lack of pigment in the iris and the retina are also contributing factors to our reduced vision, although to a lesser degree. The easiest way to understand how the lack of cones affects the vision of people with albinism is to turn on your television.
How is OCA1 caused?
OCA1 is caused by mutations in the TYR gene, where there is a complete lack of tyrosinase activity.
What does pendular nystagmus look like?
Pendular nystagmus refers to the waveform of an involuntary eye movement. In pendular nystagmus the eye moves in sinusoidal trajectory, similar to that of a pendulum. Pendular nystagmus generally does not have a “fast phase” including a saccade, but is composed entirely of slow eye movements.
Can congenital nystagmus go away?
Congenital nystagmus is present shortly after birth. Acquired nystagmus begins after 6 months of life. Congenital motor nystagmus is the most common type of congenital nystagmus. This usually occurs by itself, is not associated with any other congenital abnormalities, and does not go away but can lessen with time.