nystagmus

/nis'tægməs/

Thân thiện

A doctor uses a light to check a patient's eyes for nystagmus.

Definition

1. Noun:
   • Involuntary movements of the eyeballs: A medical condition characterized by rapid, uncontrollable, and repetitive movements of the eyes, which may be side-to-side, up and down, or rotary. The presence, type, or absence of nystagmus is used in diagnosing various neurological and visual disorders.

Usage Examples

• Noun:
  • The neurologist observed a horizontal nystagmus when the patient tried to look to the side.
  • Congenital nystagmus is often present from birth and may be associated with reduced vision.
  • The doctor tested for vestibular nystagmus by spinning the patient in a chair.

Advanced Usage

• "Optokinetic nystagmus": A normal reflexive eye movement that occurs when watching a moving object, like looking out of a train window. It is sometimes tested to assess visual tracking.

  • The optometrist used a rotating drum with stripes to elicit optokinetic nystagmus.

• "Gaze-evoked nystagmus": Eye oscillations that appear or worsen when the eyes are held in an eccentric position (looking far to one side).

  • The presence of gaze-evoked nystagmus can indicate a problem with the brainstem or cerebellum.

• "To have nystagmus": The common phrasing to indicate someone is affected by the condition.

  • Some people who have nystagmus may use a head tilt to improve their vision.

Variants and Related Words

• Nystagmic (adj): Relating to or affected by nystagmus.
  • The patient showed nystagmic movements.

Synonyms

• Eye tremor: A less formal, descriptive term for the involuntary shaking of the eyes.
• Dancing eyes: An informal, non-medical term sometimes used to describe the condition.

Related Phrases

• "Nystagmus beat": Refers to the direction of the fast phase of the eye movement in nystagmus, which is used to classify its type (e.g., right-beating nystagmus).

  • The examination revealed a left-beating nystagmus.

• "To elicit nystagmus": A medical phrase meaning to provoke or bring out the eye movements for examination.

  • The caloric test in the ear is used to elicit vestibular nystagmus.

Học thuật

Noun

1. involuntary movements of the eyeballs; its presence or absence is used to diagnose a variety of neurological and visual disorders