There is some reason to believe that a peculiar condition found in the majority of human albinoes, and known as nystagmus, is correlated with the absence of pigment in the central nervous system.
The ocular findings in albinism include nystagmus, decreased visual acuity; hypopigmentation of retinal tissue, and macular hypoplasia.
The presence of optokinetic nystagmus may not exclude loss of vision due to brain injury.
In complete human albinoes, albinism is correlated, in addition to nystagmus, with a peculiar roughness of the skin, making it harsh to the touch.
Aspects of the human condition include exotropia, accommodative esotropia, A and V patterns, dissociated vertical deviation and latent nystagmus.
A pendular nystagmus was present in all fields of gaze.
Nystagmus that appears in the first months of life is called " early onset nystagmus that appears in the first months of life is called " early onset nystagmus " or " congenital nystagmus " .
If spontaneous nystagmus is present, this must be taken into consideration when calculating both canal paresis and directional preponderance.
Symptoms of acute intoxication include unsteady gait, slurred speech and sustained nystagmus.
Glasses will not stop you having nystagmus nor are they a cure.
The condition may also develop later in life when the term " acquired nystagmus " is used.
The most common sign in foals is rapid movement of the eyes (called nystagmus ).
Overdose has resulted in symptoms including nystagmus, ataxia, impaired consciousness and coma.
Over the years, many treatments have been offered to reduce nystagmus.
Topic: Can you get nystagmus later in life?
nystagmus in early childhood may be caused by a defect in the eye or the visual pathway from the eye to the brain.
On the other hand there are many sports which are not particularly affected by nystagmus.
Infants with early-onset nystagmus are not at any special risk for neurological disease later in life.
Insight Insight is a new phone-in service for those people living with or interested in the condition nystagmus.
Causes There are many underlying causes for early- onset nystagmus.
Nystagmus Network Self help group for all those affected by the eye condition nystagmus Network Self help group for all those affected by the eye condition nystagmus.
A condition, nystagmus, which sometimes develops in infancy, causes the eyes to jump, dance, wiggle, or oscillate.
Everyone with oculocutaneous albinism experiences abnormal flickering eye movements (nystagmus) and sensitivity to bright light.
They may have a constant, involuntary movement of the eyeball called nystagmus.
There is no cure for involuntary eye movements (nystagmus), and treatments for focusing problems (surgery or contact lenses) are not effective in all cases.
Other early symptoms include changes in speech, swallowing difficulties, loss of reflexes, and jerky eye movements (nystagmus).
Chiari II malformation: Impaired swallowing and gag reflex, loss of the breathing reflex, facial paralysis, uncontrolled eye movements (nystagmus), impaired balance and gait.
Nystagmus is a condition in which there is involuntary and rhythmic movement or oscillation of the eye.
The eye movements associated with nystagmus are varied.
Nystagmus can be sensory and develop as a result of poor vision, or it can be motor and develop as a result of a neurological problem.
Nystagmus may be congenital, or it may be acquired.
Congenital, or infantile, nystagmus appears within the first few months of life.
Congenital nystagmus is usually binocular and affects both eyes, is horizontal in direction, and does not occur while the child is sleeping.
Most of these cases of nystagmus develop because of poor vision and do not have an underlying neurological cause.
Children with congenital nystagmus usually have a point in their eye movement in which the intensity of the nystagmus is decreased.
Children with nystagmus who have their the null point located at a position in which the eyes are positioned inward may develop an esotropia, a form of strabismus or eye turn.
Usually spasmus nutans appears bilaterally, and the nystagmus is in a horizontal direction.
When the nystagmus of spasmus nutans is vertical or rotary, the child does not have a head tilt.
Downbeat nystagmus is characterized by a nystagmus that is more pronounced when the child looks down, especially when looking to the side, or in lateral gaze.
An accentuated oscillation when looking up is seen in upbeat nystagmus.
Seesaw nystagmus is an unusual type of in which one eye moves in and down and the other out and up.
A periodic alternating nystagmus (PAN) is observed in primary gaze when the patient is looking straight ahead and is characterized by eye movements that continuously change direction and speed.
Peripheral vestibular nystagmus may be accompanied by vertigo, nausea, and tinnitus, or ringing in the ears.
This type of nystagmus is not always apparent but can be seen by a doctor when he or she looks in the back of the eye with a direct ophthalmoscope.
Latent nystagmus appears only when one eye is covered.
This is a congenital nystagmus caused by an ocular motor disturbance rather than visual deprivation.
A child with latent nystagmus will not see well when one eye is covered.
Gaze evoked nystagmus occurs only when one is looking to the side in extreme lateral gaze.
This type of nystagmus can be caused by ethanol and recreational drug use, but is seen in myasthenia gravis and thyroid disease as well.
If one looks at an object in extreme gaze for a long period of time, endpoint nystagmus may be noted.
Optokinetic nystagmus (OKN) is a nystagmus that can be elicited involuntarily when a rapidly moving striped object is passed in front of an individual's eyes.
Congenital nystagmus may be transmitted genetically, either as an autosomal recessive or dominant, or as an X-linked recessive trait.
Congenital nystagmus occurs twice as frequently in males than in females.
The prevalence of nystagmus in the pediatric population is .015 percent.
Eighty percent of nystagmus is congenital, and the remaining 20 percent is acquired.
The eyes of an individual with nystagmus cannot remain still and oscillate in some position of gaze.
Those with nystagmus usually have decreased vision and poor depth perception, although those born with nystagmus, may not realize that their vision is poor.
Those with acquired nystagmus may experience double vision or oscillopsia, or that objects in their visual space appear to move.
An acquired nystagmus may be accompanied by other symptoms such dizziness, difficulty with balance, hearing loss, poor coordination, and numbness.
If an individual with nystagmus experiences oscillopsia, then the nystagmus is acquired.
Other causes of acquired nystagmus are Arnold-Chiari malformations, vitamin deficiencies, syphilis, Wernicke's encephalopathy, Behcet's syndrome, and Meniere's disease.
Since nystagmus can be caused by tumors, stroke, and trauma or neurological disorder, any type of nystagmus must be evaluated by a qualified practitioner.
The nystagmus can be a sign of a serious problem.
Diagnosis of nystagmus is made primarily by patient history as reported by a parent, the age of onset, and observation of any accompanying signs such as a head turn, tilt or tremor, or oscillopsia.
If the onset is acute, then usually the nystagmus is acquired.
The type of nystagmus can accurately be determined by eye movement recordings, which map direction, frequency, null point, and amplitude of the nystagmus.
The treatment for nystagmus, once the etiology is determined and treated, includes optical devices such as contact lenses and glasses, medication, and surgery.
For individuals with nystagmus correction of refractive error with glasses or contact lenses is the first step in treating the condition.
For 85 percent of children with nystagmus, a spectacle prescription improves vision significantly.
For those with congenital nystagmus, prism may be put in glasses to help position the eye at its null point or to help the eyes converge.
Congenital nystagmus, when due to a visual deprivation, is rarely improved by surgery.
But when a head tilt or head turn accompanies nystagmus, surgery to correct a muscle imbalance may improve nystagmus and visual acuity.
When a tumor or stroke has caused an acquired nystagmus, then neurosurgery, if indicated for the underlying cause, may lead to resolution of the nystagmus.
Vestibular nystagmus can be treated by diazepam or scopolamine.
Drugs called GABA agonists, such as baclofen and carbamazepine, are useful in treatment of seesaw nystagmus and PAN, if the nystagmus is acquired and not congenital.
If the nystagmus is due to drug toxicity, then reducing or discontinuing the drug eventually resolves the problem.
Congenital nystagmus is usually a benign condition.
The best corrected vision for most individuals with congenital nystagmus is between 20/40 and 20/70, but correction to 20/20 is possible for some.
Nystagmus associated with spasmus nutans resolves spontaneously before the child reaches school age.
The prognosis for an acquired nystagmus depends on its cause.
If the condition is due to a side effect of a drug, then decreasing or changing the treatment drug eventually resolves the nystagmus.
In general nystagmus cannot be prevented.
Careful monitor of dosage of those drugs with nystagmus as a side effect may prevent the condition.
Because nystagmus can be associated with many medical problems, the child with this condition must undergo a complete ocular and neurological evaluation.
Children with nystagmus are not aware that they may have a visual deficiency and as they get older must be helped with the restrictions that nystagmus places on them.
Every effort must be made to integrate the child with nystagmus into a normal school setting in order to prepare the child for adult life, even if cosmetic concerns may instinctively lead the parent to want to protect the child.
Support for families of those with nystagmus can be found through the American Nystagmus Network.
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"Examination of the Refractive Management of Patients with Nystagmus."
"Nystagmus." Ophthalmology Clinics of North America 14 (March 2001): 205-15.
"Solving the Diagnostic Puzzle of Congenital Nystagmus."
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