What Is Downbeat Nystagmus?
Nystagmus (nystagmus; NY) is an involuntary, rhythmic, reciprocating eyeball movement. The direction is divided into horizontal type, vertical type, rotating type, etc. The horizontal type is common. The direction of nystagmus is usually expressed by the fast phase direction, and the fast phase is the compensatory restoring gaze movement. Referred to as nystagmus. It is often caused by diseases of the visual system, extraocular muscles, labyrinth of the inner ear and central nervous system. Nystagmus is not an independent disease, but a clinical manifestation of some diseases, so it is necessary to treat the cause.
Basic Information
- English name
- nystagmus
- Visiting department
- Ophthalmology
- Common locations
- eye
- Common causes
- Ocular: Difficulty in the formation of fixation reflex; Vestibular; Central, congenital
- Common symptoms
- Beating: eyeballs move back and forth with significantly different speeds; swing type: eyeballs move like a pendulum
Causes of nystagmus
- Ocular nystagmus
- Refers to visual impairment in the center of the macula, which is a nystagmus caused by difficulty in forming the gaze reflex.
- (1) Physiological fixation nystagmus includes oblique nystagmus, visual dynamic nystagmus, and recessive nystagmus.
- (2) Pathological fixation nystagmus includes blind nystagmus, amblyopia nystagmus, and occupational nystagmus.
- 2. vestibular nystagmus
- 3. Central nystagmus
- 4. Congenital idiopathic nystagmus
Clinical manifestations of nystagmus
- Beating type
- The eyeballs moved back and forth with significantly different speeds. When the eyeballs slowly turned to the other direction to a certain degree, they suddenly returned with a sharp jump motion. This type of tremor has the performance of chronic and fast phase, chronic is physiological phase, fast phase is slow phase corrective movement. The fast direction is the direction of nystagmus. The fast phase is related to the cause.
- 2.Swing type
- The eye movements are like pendulums, without fast and slow phases. Its speed and amplitude are equal. More common in patients with black eyes and amblyopia.
Nystagmus examination
- General inspection
- Ask the patient to look straight ahead and observe the nystagmus as they follow the examiner's fingers in a certain direction. Some need to be covered with a single eye for inspection. For this reason, the following points should be noted during the inspection:
- (1) Whether it is recessive or latent or dominant nystagmus.
- (2) Is nystagmus joint-the movement of the eyeballs on both sides are consistent or separate.
- (3) Type, direction, degree, frequency, and amplitude of nystagmus.
- (4) There are endless eye positions.
- 2. Special inspection
- Nystagmus current map and other equipment inspection.
Nystagmus diagnosis
- Nystagmus refers to involuntary rhythmic back and forth movements of the eyeball that can be diagnosed as nystagmus.
Nystagmus treatment
- 1. First of all, symptomatic treatment for the cause.
- 2. Surgical treatment. For congenital idiopathic nystagmus, surgical treatment can be adopted, and the resting eye is shifted directly forward to improve vision and reduce or suppress the occurrence of nystagmus.