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Sir James Galway is an Irish virtuoso flute player from Belfast, nicknamed "The Man with the Golden Flute". He established an international career as a solo flute player. In 2005, he received the Brit Award for Outstanding Contribution to Music at the Classic Brit Awards.
Achromatopsia, also known as total color blindness, is a medical syndrome that exhibits symptoms relating to at least five conditions. The term may refer to acquired conditions such as cerebral achromatopsia, but it typically refers to an autosomal recessive congenital color vision condition, the inability to perceive color and to achieve satisfactory visual acuity at high light levels, typically exterior daylight. The syndrome is also present in an incomplete form which is more properly defined as dyschromatopsia. It is estimated to affect 1 in 30,000 live births worldwide.
Benign paroxysmal positional vertigo (BPPV) is a disorder arising from a problem in the inner ear. Symptoms are repeated, brief periods of vertigo with movement, characterized by a spinning sensation upon changes in the position of the head. This can occur with turning in bed or changing position. Each episode of vertigo typically lasts less than one minute. Nausea is commonly associated. BPPV is one of the most common causes of vertigo.
Alexander's law refers to gaze-evoked 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 attenuated 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.
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 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.
The flocculonodular lobe (vestibulocerebellum) is a lobe of the cerebellum consisting of the nodule and the flocculus. The two flocculi are connected to the midline structure called the nodulus by thin pedicles. It is placed on the anteroinferior surface of cerebellum.
Vertigo is a condition where a person has the sensation of moving or of surrounding objects moving when they are not. Often it feels like a spinning or swaying movement. This may be associated with nausea, vomiting, sweating, or difficulties walking. It is typically worse when the head is moved. Vertigo is the most common type of dizziness.
Internuclear ophthalmoplegia (INO) is a disorder of conjugate lateral gaze in which the affected eye shows impairment of adduction. When an attempt is made to gaze contralaterally, the affected eye adducts minimally, if at all. The contralateral eye abducts, however with nystagmus. Additionally, the divergence of the eyes leads to horizontal diplopia. That is, if the right eye is affected the patient will "see double" when looking to the left, seeing two images side-by-side. Convergence is generally preserved.
Parinaud's syndrome is an inability to move the eyes up and down. It is caused by compression of the vertical gaze center at the rostral interstitial nucleus of medial longitudinal fasciculus (riMLF). The eyes lose the ability to move upward and down.
In medicine, the caloric reflex test is a test of the vestibulo-ocular reflex that involves irrigating cold or warm water or air into the external auditory canal. This method was developed by Robert Bárány, who won a Nobel prize in 1914 for this discovery.
The Dix–Hallpike test — or Nylén–Bárány test — is a diagnostic maneuver used to identify benign paroxysmal positional vertigo (BPPV).
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.
Tridihexethyl is an anticholinergic, antimuscarinic and antispasmodic drug. It may be used, usually in combination with other drugs, to treat acquired nystagmus or peptic ulcer disease. Many patients discontinue the drug because of unwanted side effects.
The term gaze is frequently used in physiology to describe coordinated motion of the eyes and neck. The lateral gaze is controlled by the paramedian pontine reticular formation (PPRF). The vertical gaze is controlled by the rostral interstitial nucleus of medial longitudinal fasciculus and the interstitial nucleus of Cajal.
Nystagmus is a condition of involuntary eye movement, acquired in infancy or later in life, that in extremely rare cases may result in reduced or limited vision. Due to the involuntary movement of the eye, it has been called "dancing eyes".
Positional alcohol nystagmus (PAN) is nystagmus 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.
Biemond syndrome is a genetic disorder characterised by brachydactyly, nystagmus, strabismus, cerebellar ataxia and intellectual disability.
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 when looking towards the side of the lesion, and rapid, small amplitude 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. 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.
Field sobriety tests (FSTs), also referred to as standardized field sobriety tests (SFSTs), are a battery of tests used by police officers to determine if a person suspected of impaired driving is intoxicated with alcohol or other drugs. FSTs are primarily used in the US, to meet "probable cause for arrest" requirements, necessary to sustain an alcohol-impaired driving conviction based on a chemical blood alcohol test.
Pendular nystagmus is a sinusoidal oscillation, which refers to the waveform of involuntary eye movements that may occur in any direction. It is characterized by the multidimensional slow eye movements of the eyes with an equal velocity in each direction that resembles the trajectory of a pendulum. These pattern of these movements may differ between the two eyes. Depending upon the pattern of movements, pendular nystagmus has been divided into different subtypes such as congenital nystagmus, acquired pendular nystagmus, and amaurotic nystagmus.
References
- ↑ Miller, Maurice H.; Schein, Jerome Daniel (2008). Hearing Disorders Handbook. Plural Publishing. ISBN 9781597568388.
- ↑ "amaurotic nystagmus". Academic Dictionaries and Encyclopedias. Retrieved 2017-12-16.
- ↑ Agarwal, Amar (2015-05-10). Manual of Neuro-ophthalmology. JP Medical Ltd. ISBN 9789351527824.