vestibular function - getting the balance right

Question 1

What are the sensory organs of the semicircular canal

Answer 1

Sensory hair cells

Question 2

What are the otolith organs

Answer 2

utricle and saccule

Question 3

What kind of acceleration does the utricle detect

Answer 3

Back/ front tilt and horizontal acceleration

Question 4

What kind of acceleration does the saccule detect

Answer 4

Vertical

Question 5

What kind of acceleration does the semiciruclar canals detect

Answer 5

Rotational acceleration

Question 6

Where are the sensory hair cells located in the vestibular apparatus

Answer 6

Within the ampulla in a gelatinous structure called the cupula

Question 7

How does the rotational acceleration get detected by the semicircular canal

Answer 7

The endolymph snt moved at first when the skull is rotated but the ampulla moves instantly as it is part of the skull - there is a drag produced by the endolymph which bends the cupula and the cilia embedded within it - the endolymph eventually catches up which stops the cycle

Question 8

If there is left flick back of the eye, which direction is the nystagmus and why

Answer 8

The rotation would be to the left which pushes the eye to the right and then the eye would flick back left when it reaches the bony orbit

Question 9

Describe caloric stimulation

Answer 9

Outer ear washed with Warm fluid causes nystagmus to the affected side and cold causes nystagmus to the unaffected side

Question 10

What is vertigo

Answer 10

perception of movement in the absence of movement

Question 11

Describe the presentation of menieres disease

Answer 11

• Vertigo
• Nausea
• Nystagmus
• tinnitus
• Aural fullness