3rd, 4th, 5th, 6th, 7th Nerve Syndromes Flashcards
What are the 6 syndromes of the 6th nerve?
- Brainstem syndrome
- Subarachnoid space syndrome (pseudotumor - tethering in Dorello’s canal)
- Petrous apex syndrome
- Cavernous sinus syndrome
- Orbital syndrome
- isolated 6th nerve palsy
What are the 3 brainstem syndromes of CN6?
- Millard-Gubler syndrome (6,7,contralateral hemiparesis)
- Raymonds syndrome (6+contralateral hemiparesis)
- Foville’s syndrome (5-8 palsy + Ipsilateral Horner’s syndrome)
What are the 3 Petrous Apex Syndrome?
- Gradenigo’s - 6th nerve palsy + ipsilateral decreased hearing, facial pain, facial paralysis)
- Petrous skull fracture - 5-8 CN involvement
- Pseudo-Gradenigo - nasopharyngeal carcinoma or CPA tumor
What innervates the SR muscle?
The CONTRALATERAL 3rd nerve nucleus
What innervates the levator muscle?
Both levators are innervated by ONE subnuclear structure - central caudal nucleus–> there fore a nuclear 3rd requires b/l ptosis
What are the 4 fascicle 3rd nerve syndromes?
- Nothnagel - Ipsilateral 3rd nerve + cerebellar ataxia (lesion in area of the superior cerebellar peduncle)
- Benedikt’s syndrome - lesion of the red nucleus (ipsi 3rd nerve with contralateral hemitremor)
- Weber’s syndrome - (lesion of cerebral peduncle) - ipsi 3rd with contra hemiparesis
- Claude - both benedikt + Nothnagel
Fascicular lesions always ischemic, infiltrative, or rarely inflm
What are the 2 vessels that the 3rd + 4th nerve courses betwn in the midbrain?
- Posterior Cerebral Artery (top)
2. Superior Cerebellar Artery (bottom)
When does abberant regeneration of 3rd nerve occur?
- Tumor
- Trauma
(never to ISCHEMIA)
Whart are the 2 clinical phenomenon of abberant regeneration?
- Lid-Gaze dyskinesis
2. Pupil-gaze dyskinesis
What CN is the only one to exit the dorsal aspect of the brainstem?
CN 4
Which CN has the longest intracranial nerve?
CN 4 (75mm)
The left nerve fascicle innervates what muscle?
R SO
What are the 5 syndromes of CN 4?
- Nuclear-Fascicular syndrome
- Subarachnoid space syndrome
- Cavernous sinus syndrome
- Orbital syndrome
- Isolated CN 5 palsy
In Brown’s syndrome what adaptations occur?
- Chin up position ( affected eye usually hypotropic)
2. Face turn (AWAY from Brown’s eye)
What causes paroxysmal, rapid, vertical, and torsional movements of one eye that are usually small, necessitating slit-lamp exam?
SO myokymia (tx with carbamazepine)
In double maddox rod test which line is one top?
White
Greater than how many degrees of torsion suggestive b/l 4th nerve palsy?
10 degrees (also large V pattern stab >25D)
How do you differentiate 4th nerve palsy from skew deviation?
Skew - increased vertical strabismus on up gaze
4th nerve - increased on down gaze
What type of inflm do you see in Tolosa-Hunt?
Granulomatous
In Botulism what happens with pupils?
Dilated, poorly reactive pupils, ptosis
What is the bulbar variant of Guillain-Barre syndrome?
Miller Fisher syndrome - pupils involved with loss of accomadation.
What are the 2 functions of CN5?
- Ipsilateral sensory
2. Ipsilateral motor - muscles of mastication (masseter, temporalis, pterygoids)
Concentric periporal numbness has the lesion where?
Central (nuclear) origin - ischemic, demylination
What is CN5 nerve distribution pain with ipsilateral Horner’s syndrome?
Raeder’s paratrigeminal neuralgia
- middle aged or elderly males
A supranuclear facial nerve palsy causes what?
Contralateral weakness of the lower 2/3 of the face
The incidence of Bell’s palsy higher in what 3 people?
- Pregnant
- DM
- Fhx of Bell’s
What muscles are affected in Bell’s palsy?
BOTH the upper and lower face muscles unilaterally.
What is the name of the dz that has recurrent, alternating facial palsy with facial swelling, transverly fissured tongue in kids ?`
Melkersson-Rosenthal syndrome
What 7th nerve d/o is due to dysfunction at the basal ganglia?
blepharspasm (b/l)
The 7th CN affect taste where?
Anterior 2/3 of tongue.
Which nerve palsy has aberrant regeneration?
7th (10-20%)»_space;>3rd nerve
7th - blepharospasm, hemifacial spasm
Which 7th nerve palsy causes total unilateral facial droop?
Lower motor neuron (upper motor neuron only causes contralateral lower face droop)
Webers causes what?
3rd nerve fasicle paresis with contraleteral hemiparesis (Weber = WEAK)
Claudes causes what?
3rd nerve fasicular palsy at the superior cerebellar peduncle causes ipsi 3rd with contralteral ataxia (Claude = CLUMPSY)
An eye with a 4th nerve palsy will look like what in primary gaze?
Nasal upshoot - when looking nasal
