Cranial Nerve Pathologies Flashcards
Trigeminal neuralgia
- pathophysiology, presentation
- causes (primary, secondary)
- investigations
- management
Primary - idiopathic
Secondary
-something pushing on the nerve - tumour, pulsation of artery => stimulates and demyelinates nerve
-MS
-inflammation of nerve - herpes zoster opthalmicus (PHN, Hutchinsons sign, corneal blisters)
Neuropathic pain
- Sudden, short, severe, electric, sharp, shooting dermatomal pain
- Regular short frequent attacks
- can be triggered by light touch
- 5678 involved => acoustic neuroma?
CPA MRI
Carbemazipine - pain
Manage underlying cause
-surgery => risk of stroke, hearing loss
Facial palsy
- presentation and signs
- how does this differ from a stroke
Tear hear taste face
Stroke
- Cortex =(nerves bilateral innervation nerve)=> facial nucleus
- no forehead involvement
Facial nerve palsy - LMN
- cannot close eye
- Bells phenomena
- hyperacusis
- change in taste
Ramsey Hunt, herpes zoster oticus
Self limiting
- recovery speed up if CS given within 3 days
- add aciclovir for RHS
- tape eye closed at night to prevent it drying out
Vestibular nerve issues
- presentation
- differentiating between brainstem and vestibular nerve issues
Vestibular nerve - vertigo (feel they are spinning/room is spinning around them)
Bilateral vestibular input needed
- difficulty walking straight
- nystagmus - eye drifts laterally and jerks back to midline
Head impulse test
- how would you do this
- when would you do this
Ask patient to focus on your nose
Ask patient if they have neck pain
Hold head from side, gently move it from side to side whilst asking patient to keep their eyes locked on your nose
Vestibular nerve damage - eyes unlock from nose and lock back on (saccade)
Brainstem damage - pure vertical nystagmus or nystagmus that changes direction with no ext stimulus
Differentiate between peripheral nystagmus and central nystagmus
-central nystagmus can be caused by a stroke
Glossopharyngeal, vagus involvement
Swallowing
Post 1/3 tongue taste - difficult to test
Gag reflex - only tested in ICU comatose patients
-can be tested with tongue depressor
Dysphonia => ENT referral
-potential hilar tumour
Bulbar palsy
- presentation
- causes
LMN issue affecting 9-12
- tongue wasting => deviation to affected side
- dysarthria, dysphagia, dysphonia
Causes
- medullary infarction
- ALS, GBS
- malignancy
Pseudobulbar palsy
- presentation
- causes
UMN issue - stroke
- slow tongue mv
- stroke-like facial involvement
- jaw hyperreflexia
- incongruent mood - due to loss of UMN disinhibition
Wallenburg Syndrome
- what is it
- common causes
- presentation
- diagnosis
- management
PICA or vertebral artery blocked => ischemia of lateral medulla
Contralateral trunk, limbs -loss pain, temp Ipsilateral face -loss pain, temp -9, 10 => dysphagia, hoarse, no gag Ipsilateral cerebellar signs Loss of SNS => ipsilateral Horners, bradycardia -tracts that innervate sympathetic chain pass through medulla Vestibular nuclei => dizzy ataxia
Most common cause - stroke
- CT , MRI head with contrast
- stroke unit
- ischemic - aspirin, thrombolysis if U4.5, thrombectomy if U6
- haemorrhagic - BP control and neurosurgery
Prognosis generally good but depends on severity
Lateral pontine syndrome
- what is it
- common causes
- presentation
AICA blockage => ischemia of lateral pons
Contralateral trunk and limb -loss pain, temp Ipsilateral face -V loss of all sensory modalitites -VI hearing and loss of vestibular function (nystagmus, N+V, vertigo) -VII non forehead sparing LMN, no lacrimation, salivation, corneal reflex, 2/3 ant taste Ipsilateral cerebellar Ipsilateral SNS loss => Horners
Cerebellar pathologies
- presentation
- common causes of damage
- when should you be concerned
Ipsilateral DANISH
Midline damage - disruption of whole body mv
Lateral damage - disrupt fine mv of hands, limbs
Dizziness
Common causes of damage
- stroke, hemorrhage, trauma
- tumours
- alcohol
Dizziness +
sudden limb sensory/motor loss
CV symptoms, falls, seizures
