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Congenital nystagmus has traditionally been viewed as non-treatable, but medications have been discovered in recent years that show promise in some patients. In 1980, researchers discovered that a drug called baclofen could effectively stop periodic alternating nystagmus. Subsequently, gabapentin, an anticonvulsant, was found to cause improvement in about half the patients who received it to relieve symptoms of nystagmus. Other drugs found to be effective against nystagmus in some patients include memantine, levetiracetam, 3,4-diaminopyridine (available in the US to eligible patients with downbeat nystagmus at no cost under an expanded access program), 4-aminopyridine, and acetazolamide. Several therapeutic approaches, such as contact lenses, drugs, surgery, and low vision rehabilitation have also been proposed. For example, it has been proposed that mini-telescopic eyeglasses suppress nystagmus.
Surgical treatment of Congenital Nystagmus is aimed at improving the abnormal head posture, simulating artificial divergence or weakening the horizontal recti muscles. Clinical trials of a surgery to treat nystagmus (known as tenotomy) concluded in 2001. Tenotomy is now being performed regularly at numerous centres around the world. The surgery developed by Louis F. Dell'Osso Ph.D. aims to reduce the eye shaking (oscillations), which in turn tends to improve visual acuity.
Acupuncture has conflicting evidence as to having beneficial effects on the symptoms of nystagmus. Benefits have been seen in treatments where acupuncture points of the neck were used, specifically points on the sternocleidomastoid muscle. Benefits of acupuncture for treatment of nystagmus include a reduction in frequency and decreased slow phase velocities which led to an increase in foveation duration periods both during and after treatment. By the standards of evidence-based medicine, the quality of these studies can be considered poor (for example, Ishikawa has a study sample size of just six, is unblinded and without proper control), and given high quality studies showing that acupuncture has no effect beyond placebo, the results of these studies have to be considered clinically irrelevant until higher quality studies are produced.
Physical therapy or Occupational therapy is also used to treat nystagmus. Treatment consist of learning compensatory strategies to take over for the impaired system.
It may be acquired from:
- Diseases. Some of the diseases that present nystagmus as a pathological sign:
- Aniridia
- Toxic or metabolic reasons could be the result of the following:
- Central nervous system (CNS) disorders, such as with a cerebellar problem, the nystagmus can be in any direction "including" horizontal. Purely vertical nystagmus is usually central in origin, but it is also a frequent adverse effect of high phenytoin toxicity. Causes include:
The optokinetic response is a combination of a slow-phase and fast-phase eye movements. It is seen when an individual follows a moving object with their eyes, which then moves out of the field of vision at which point their eye moves back to the position it was in when it first saw the object. The reflex develops at about 6 months of age.
Optokinetic nystagmus (OKN) is nystagmus that occurs in response to a rotation movement. It is present normally. The optokinetic response allows the eye to follow objects in motion when the head remains stationary (e.g., observing individual telephone poles on the side of the road as one travels by them in a car, or observing stationary objects while walking past them).
According to a Cochrane review of 2012, controversies remain regarding type of surgery, non-surgical intervention and age of intervention.
The aims of treatment are as follows:
The elimination of any amblyopia
A cosmetically acceptable ocular alignment
long term stability of eye position
binocular cooperation.
It is essential that a child with strabismus is presented to the ophthalmologist as early as possible for diagnosis and treatment in order to allow best possible monocular and binocular vision to develop. Initially, the patient will have a full eye examination to identify any associated pathology, and any glasses required to optimise acuity will be prescribed – although infantile esotropia is not typically associated with refractive error. Studies have found that approximately 15% of infantile esotropia patients have accommodative esotropia. For these patients, antiaccommodative therapy (with spectacles) is indicated before any surgery as antiaccommodative therapy fully corrects their esotropia in many cases and significantly decreases their deviation angle in others.
Amblyopia will be treated via occlusion treatment (using patching or atropine drops) of the non-squinting eye with the aim of achieving full alternation of fixation. Management thereafter will be surgical. As alternative to surgery, also botulinum toxin therapy has been used in children with infantile esotropia. Furthermore, as accompaniment to ophtalmologic treatment, craniosacral therapy may be performed in order to relieve tension ("see also:" Management of strabismus).
Amaurotic nystagmus is defined as the nystagmus associated with blindness or the central vision defects. It is characterized by the pendular or jerky movements of the eyes in the patients who have visual impairement for a long period of time.
Sedative drugs are often prescribed for vertigo and dizziness, but these usually treat the symptoms rather than the underlying cause. Lorazepam (Ativan) is often used and is a sedative which has no effect on the disease process, but rather helps patients cope with the sensation.
Anti-nauseants, like those prescribed for motion sickness, are also often prescribed but do not affect the prognosis of the disorder.
Specifically for Meniere's disease a medication called Serc (Beta-histine) is available. There is some evidence to support its effectiveness in reducing the frequency of attacks. Also Diuretics, like Diazide (HCTZ/triamterene), are effective in many patients. Finally, ototoxic medications delivered either systemically or through the eardrum can eliminate the vertigo associated with Meniere's in many cases, although there is about a 10% risk of further hearing loss when using ototoxic medications.
Treatment is specific for underlying disorder of balance disorder:
- anticholinergics
- antihistamines
- benzodiazepines
- calcium channel antagonists, specifically Verapamil and Nimodipine
- GABA modulators, specifically gabapentin and baclofen
- Neurotransmitter reuptake inhibitors such as SSRIs, SNRIs and Tricyclics
If an optokinetic drum is available, rotate the drum in front of the patient. Ask the patient to look at the drum as you rotate it slowly. If an optokinetic drum is not available, move a strip of paper with alternating 2-inch black and white strips across the patient's visual field. Pass it in front of the patient's eye at reading distance while instructing the patient to look at it as it rapidly moves by. With normal vision, a nystagmus develops in both adults and infants. The nystagmus consists of initial slow phases in the direction of the stimulus (smooth pursuits), followed by fast, corrective phases (saccade). Presence of nystagmus indicates an intact visual pathway.
Another effective method is to hold a mirror in front of the patient and slowly rotate the mirror to either side of the patient. The patient with an intact visual pathway will maintain eye contact with herself or himself. This compelling optokinetic stimulus forces reflex slow eye movements.
OKN can be used as a crude assessment of the visual system, particularly in infants. When factitious blindness or malingering is suspected, check for optokinetic nystagmus to determine whether there is an intact visual pathway.
Dysequilibrium arising from bilateral loss of vestibular function – such as can occur from ototoxic drugs such as gentamicin – can also be treated with balance retraining exercises (vestibular rehabilitation) although the improvement is not likely to be full recovery.
Bruns nystagmus is an unusual type of bilateral nystagmus most commonly occurring in patients with cerebellopontine angle tumours. It is caused by the combination of slow, large amplitude nystagmus (gaze paretic nystagmus) when looking towards the side of the lesion, and rapid, small amplitude nystagmus (vestibular nystagmus) when looking away from the side of the lesion. It occurs in 11% of patients with vestibular schwannoma, and occurs mainly in patients with larger tumours (67% of patients with tumours over 3.5 cm diameter). Bruns nystagmus is also associated with an increased incidence of balance disturbance in patients with vestibular schwannoma. It may be caused by the compression of both flocculi, the vestibular part of the cerebellum, and improvement in both the nystagmus and balance problems occur commonly after removal of the tumour.
Bruns nystagmus is named for Ludwig Bruns (1858 – 1915).
Alexanders law refers to spontaneous nystagmus that occurs after an acute unilateral vestibular loss. It was first described in 1912 and has three elements to explain how the vestibulo-ocular reflex responds to an acute vestibular insult. The first element says that spontaneous nystagmus after an acute vestibular impairment has the fast phase directed toward the healthy ear. The direction of the nystagmus, by convention, is named for the fast phase, so the spontaneous nystagmus is directed toward the healthy ear. The second element says nystagmus is greatest when gaze is directed toward the healthy ear, is attentuated at central gaze and may be absent when gaze is directed toward the impaired ear. The third element says that spontaneous nystagmus with central gaze is augmented when vision is denied. This became apparent with the implementation of electrographic testing.
Alexander's law states that in individuals with nystagmus, the amplitude of the nystagmus increases when the eye moves in the direction of the fast phase (saccade).
It is manifested during spontaneous nystagmus in a patient with a vestibular lesion. The nystagmus becomes more intense when the patient looks in the quick-phase than in the slow-phase direction.
The law was named after Gustav Alexander who described it in 1912.
A number of maneuvers have been found to be effective including: the Epley maneuver, the Semont maneuver, and to a lesser degree Brandt–Daroff exercises. Both the Epley and the Semont maneuver are equally effective.
Oscillopsia is a visual disturbance in which objects in the visual field appear to oscillate. The severity of the effect may range from a mild blurring to rapid and periodic jumping. Oscillopsia is an incapacitating condition experienced by many patients with neurological disorders. It may be the result of ocular instability occurring after the oculomotor system is affected, no longer holding images steady on the retina. A change in the magnitude of the vestibulo-ocular reflex due to vestibular disease can also lead to oscillopsia during rapid head movements. Oscillopsia may also be caused by involuntary eye movements such as nystagmus, or impaired coordination in the visual cortex (especially due to toxins) and is one of the symptoms of superior canal dehiscence syndrome. Sufferers may experience dizziness and nausea. Oscillopsia can also be used as a quantitative test to document aminoglycoside toxicity. Permanent oscillopsia can arise from an impairment of the ocular system that serves to maintain ocular stability. Paroxysmal oscillopsia can be due to an abnormal hyperactivity in the peripheral ocular or vestibular system.
No known treatment for BPT currently exists. However, the condition it is self-limiting and resolves after about eighteen months.
The Epley maneuver employs gravity to move the calcium crystal build-up that causes the condition. This maneuver can be performed during a clinic visit by health professionals, or taught to patients to practice at home, or both. Postural restriction after the Epley maneuver increases its effect somewhat.
When practiced at home, the Epley maneuver is more effective than the Semont maneuver. The most effective repositioning treatment for posterior canal BPPV is the therapist-performed Epley combined with home-practiced Epley maneuvers. Devices like the DizzyFIX can help users conduct the Epley maneuver at home, and are available for the treatment of BPPV.
The Epley maneuver does not address the actual presence of the particles (otoconia); rather it changes their location. The maneuver aims to move these particles from some locations in the inner ear which cause symptoms such as vertigo, and reposition them to where they do not cause these problems.
Unfortunately, there is no real way to prevent against vertiginous episodes out of the means of managing the disease. As head trauma is a major cause for vertiginous epilepsy, protecting the head from injury is an easy way to avoid possible onset of these seizures. With recent advances in science it is also possible for an individual to receive genetic screening, but this only tells if the subject is predisposed to developing the condition and will not aid in preventing the disease.
There is a range of ways to manage vertiginous epilepsy depending on the severity of the seizures. For simple partial seizures medical treatment is not always necessary. To the comfort of the patient, someone ailed with this disease may be able to lead a relatively normal life with vertiginous seizures. If, however, the seizures become too much to handle, antiepileptic medication can be administered as the first line of treatment. There are several different types of medication on the market to deter epileptic episodes but there is no support to show that one medication is more effective than another. In fact, research has shown that simple partial seizures do not usually respond well to medication, leaving the patient to self-manage their symptoms. A third option for treatment, used only in extreme cases when seizure symptoms disrupt daily life, is surgery wherein the surgeon will remove the epileptic region.
There have been early and consistent strategies for measurement to better understand vertiginous epilepsy including caloric reflex test, posture and gait, or rotational experimentation.
In Japan, Kaga et al prepared a longitudinal study of rotation tests comparing congenital deafness and children with delayed acquisition of motor system skills. They were able to demonstrate the development of post-rotation nystagmus response from the frequency of beat and duration period from birth to six years to compare to adult values. Overall, the study demonstrated that some infants from the deaf population had impaired vestibular responses related to head control and walking age. A side interpretation included the evaluation of the vestibular system in reference to matching data with age.
Research in this area of medicine is limited due to its lacking need for urgent attention. But, the American Hearing Research Foundation (AHRF) conducts studies in which they hope to make new discoveries to help advance treatment of the disease and possibly one day prevent vertiginous seizures altogether.
Benign paroxysmal torticollis disappears in the early years of life with no medical intervention.
However, some cases of benign paroxysmal torticollis cases can evolve into benign paroxysmal vertigo of childhood, migrainous vertigo or typical migraines.
Ocular stability is maintained by three different ocular motor systems
1. The fixation system and its deficit
2. The visuo-vestibular stabilizing systems and their deficits
3. The neural integrator and its deficit
There is generally no treatment to cure achromatopsia. However, dark red or plum colored filters are very helpful in controlling light sensitivity.
Since 2003, there is a cybernetic device called eyeborg that allows people to perceive color through sound waves. Achromatopsic artist Neil Harbisson was the first to use such a device in early 2004, the eyeborg allowed him to start painting in color by memorizing the sound of each color.
Moreover, there is some research on gene therapy for animals with achromatopsia, with positive results on mice and young dogs, but less effectiveness on older dogs. However, no experiments have been made on humans. There are many challenges to conducting gene therapy on humans. See Gene therapy for color blindness for more details about it.
Positional alcohol nystagmus (PAN) is nystagmus (visible jerkiness in eye movement) produced when the head is placed in a sideways position. PAN occurs when the specific gravity of the membrane space of the semicircular canals in the ear differs from the specific gravity of the fluid in the canals because of the presence of alcohol.
The treatment for vestibular neuronitis depends on the cause. However, symptoms of vertigo can be treated in the same way as other vestibular dysfunctions with vestibular rehabilitation.
Zonular cataract and nystagmus, also referred as Nystagmus with congenital zonular cataract is a rare congenital disease associated with Nystagmus and zonular cataract of the eye.
In most cases, between the age of 2 and 4 oculomotor signals are present. Between the age of 2 and 8, telangiectasias appears. Usually by the age of 10 the child needs a wheel chair. Individuals with autosomal recessive cerebellum ataxia usually survive till their 20s; in some cases individuals have survived till their 40s or 50s.
When a person consumes alcohol, the alcohol is carried by the bloodstream and diffused into the water compartments of the body. Normally, the specific gravity of a canal membrane is the same as the specific gravity of the surrounding fluid. Because of this, even though the Earth's gravity is a constant force of acceleration, the semicircular canals do not respond to it. Alcohol has a lighter specific gravity than water. When alcohol enters the canal membrane via capillaries, the specific gravity of the membrane is lower than that of the surrounding fluid. The alcohol does diffuse from the membrane to the fluid, but it does so very slowly. While the specific gravity of the membrane is lower than the specific gravity of the extracellular fluid, the hair cells on the membrane become responsive to the Earth's gravity. This is the condition of PAN I.
PAN I is characterized by a nystagmus to the right when the right side of the head is down. It is typically present during a rising and peak Blood Alcohol Concentration (BAC).