Nystagmus
Contents
- 1 Nystagmus most commonly occurs when the ———— stimulated while the head is stationary.
- 2 Which of the following is most appropriate? Direction of ocular movement is related to –
- 3 Which is the most common form of nystagmus?
- 4 Most common genetic cause of X-linked congenital nystagmus is a mutation in –
- 5 Horizontal jerks nystagmus results from testing oculomotor movements too far laterally is called as –
- 6 Which of the following nystagmus is characterized by the multidimensional slow eye movements of the eyes with an equal velocity in each direction?
- 7 Extra-Points
- 8 What is “dancing eyes”?
- 9 When we rotate our head how the gaze is fixed on an object as the head moves?
- 10 What is the difference between peripheral vestibular nystagmus and central vestibular nystagmus?
- 11 What is Alexander’s law?
- 12 What is Caloric nystagmus?
- 13 What is ‘Spasmus nutans’ ?
- 14 What are the components of a Nystagmus?
Nystagmus most commonly occurs when the ———— stimulated while the head is stationary.
A. cochlea
B. semi-circular canals
C. auditory nerve
D. spiral ganglion
A. Position of patient
B. Direction of light source
C. Direction of movement
D. Semicircular canal that is being stimulated
Which is the most common form of nystagmus?
A. Congenital nystagmus
B. Multiple sclerosis
C. Alcoholic
D. Ménière’s disease
Most common genetic cause of X-linked congenital nystagmus is a mutation in –
A. IRF4 gene
B. DLX1 gene
C. GJB2 gene
D. FMRD7 gene
Horizontal jerks nystagmus results from testing oculomotor movements too far laterally is called as –
A. Optokinetic nystagmus
B. Pendular nystagmus
C. Physiologic end-point nystagmus
D. Post-rotational nystagmus
Which of the following nystagmus is characterized by the multidimensional slow eye movements of the eyes with an equal velocity in each direction?
A. Pendular nystagmus
B. Per-rotational nystagmus
C. Post-rotational nystagmus
D. End-point nystagmus
Extra-Points
What is “dancing eyes”?
Involuntary movement of the eye IN Nystagmus is called – “dancing eyes”
When we rotate our head how the gaze is fixed on an object as the head moves?
- Once head moves or turns – semicircular canals in the vestibule of the ear sense angular acceleration, and send signals to the nuclei for eye movement in the brain.
- From here, a signal is relayed to the extraocular muscles to allow one’s gaze to fix on an object as the head moves.
What is the difference between peripheral vestibular nystagmus and central vestibular nystagmus?
Unique characteristic of peripheral vestibular nystagmus is the dampening effect on the nystagmus by visual fixation, which is in contrast to central vestibular nystagmus.
What is Alexander’s law?
Alexander’s law – states that nystagmus increases in amplitude and frequency as the patient looks in the direction of the fast phase.
What is Caloric nystagmus?
Caloric nystagmus – elicited by stimulating the tympanic membrane and horizontal semicircular canals with either warm or cold water.
- Cold stimulus – eyes will turn slowly towards the cold water stimulation with rapid nystagmus away. Absence may indicate brain death.
- Warm stimulus- eyes will turn slowly away with rapid nystagmus toward the side of the stimulus. Absence may indicate brain death.
What is ‘Spasmus nutans’ ?
Spasmus nutans is a disorder that includes the clinical triad of
- nystagmus,
- head nodding,
- torticollis
What are the components of a Nystagmus?
- First movement – Starts by a slow movement of the eye away from the visual target.
- Second movement – Brings the eye back to the visual target.
Pendular nystagmus – second movement is slow
Jerk nystagmus – second movement is quick