Thursday 18 November 2010

a 66-year-old woman with dizziness

we saw a very nice lady today along with her daughter

the main issue was 'dizziness'

we returned (again) to the confusing terminology and the need to take a detailed history

important categories of explanation were:

vertigo
orthostatic hypotension
cerebellar disorders
weakness
seizures
syncope
other stuff
_ _ _

our lady had an acute disorder affecting her balance with unsteadiness of the visual environment which sounded like vertigo

i recently had the chance to hear an excellent lecture on vertigo by a professor at imperial called adolfo bronstein (he has written a book called dizziness)

this is essentially his approach

the 3 syndromes to be considered are:

- a single episode (most likely to be vestibular neuritis)
- recurrent vertigo (eg BPPV or migraine)
- chronically off balance(eg gentamicin toxicity)

_ _ _

this lady had a single event

the key issue is whether there is a central (brainstem) or peripheral cause (vestibular nerve)

with central lesions abnormalities of other cranial nerves are likely to be found so they need to be tested for carefully

the anterior inferior cerebellar artery which supplies the labyrinth also supplies the cochlea so with a stroke hearing loss is likely

hence a vital question is "have you gone deaf?"

_ _ _

our patient had no hearing loss and had features of a flu-like illness

we examined her cranial nerves and these were intact

importantly she had no nystagmus or cranial nerve palsies

her hearing was normal

we performed a head impulse test (also called head thrust or halmagyi test) showed a slowed response on the right

all of this points to an acute labyrinthitis

_ _ _

we went through cranial nerve examination slowly

again the key is clear instruction!

we thought about which nerves are being tested during which extra-ocular movements

we also thought about simple testing of the quadrants for visual fields

and the need for good visibility when testing palatal movement
_ _ _

bppv causes episodic vertigo and is due to debris in the posterior semi-circular canal



it is made worse when turning to a particular side when lying down

halpikes manoeuvre is used to diagnose this; the semont manoeuvre is used to treat bppv and is successful 80% of the time


menieres syndrome causes hearing loss and is rare