Tuesday, March 31, 2009


Pathway:
Posterolateral hypothalamus --> 1st order neurone
1st order neuron terminates at ciliospinal center of BUDGE at C8-T2 (T1)
2nd order neuron: from Ciliospinal centre of BUDGE enters cervical sympathetic chain
Terminates at the superior cervical ganglion at the bifurcation of CCA at C3-C4
3rd order neuron (post ganglionic pupillomotor fibres) exit the ganglion and ascends via ICA entering cavernous sinus, briefly joining CN6 before entering orbit via SOF with CNV1 via the long ciliary nerve which innervates the pupillary dilator and Mullers
3rd order neuron (post ganglionic sudomotor and vasomotor) branch off the ganglion and travel along ECA to innervate the face.
Clinical S/S:
- miosis (paralysis of pupillary dilator)
- enopthalmos (loss of tone of the muscles of the floor of orbit
- partial ptosis (loss of tone of superior tarsal muscle of Muellers)
- slight elevation of lower lid (upside down ptosis due to loss of tone of lower tarsal muscles)
Features would be seen in congenital horners: heterochromia
Diagnosis:
2 tests: cocaine 4% or adrenaline 1:1000
These tests help us determine whether it is above or below the superior cervical ganglion
For example, with a lesion distal to the superior cervical ganglion:
addition of cocaine 4% will:
affected eye --> no changes
unaffected eye --> dilates
for a lesion proximal to the superior cervical ganglion:
affected eye --> dilates
unaffected eye --> dilates
Another example with adrenaline 1:1000 eyedrops:
Distal lesion:
affected eye --> dilates
unaffacted eye --> no changes
Proximal lesions:
affected eye: no change
unaffected eye: no change
Thus if a patient presents with unilateral partial ptosis with upside down ptosis: check for vasomotor and sudomotor changes to determine level. If you suspect the patient having a lesion proximal to the superior cervical ganglion: look at the neck. In the local context, most probably due to pancoast tumour. So what you should do:
1. ask about sudomotor and vasomotor symptoms (to confirm suspicion of level)
2. offer to do and actually inspect and examine the lower neck for signs of SVCO and cervical lymphadenopathy
3. offer to examine the upper chest
4. offer confirmatory tests: 4% cocaine and 1:1000 adrenaline, of which the affected eye will dilate with 4% cocaine but will not with 1:1000 adrenaline
ACE I is good for controlling BP in patiens with CCF (probably helps in reducing secondary hyperaldosteronism)

Cardioselective beta blockers: CMM
Carvedilol
Misoprolol
Metoprolol
Bulbar palsy vs Pseudobulbar palsy:
- Bulbar palsy affects CN 9 10 11 12 (forgive me i am lazy to use romans) at the nuclear, fascicular or nerve level
- Pseudobulbar palsy affects the corticobulbar tracts, usually vascular causes affecting the internal capsule

To differentiate the two
Pseudobulbar palsy:
Emotions: labile
Dysarthria: donald duck/hot potato speech
Tongue: spastic, small for size
Jaw Jerk: brisk
Associated findings: bilateral UMNL of limbs

Bulbar palsy:
Emotions: normal
Speech: nasal
Tongue: wasted, fasciculations
Jaw jerk: N
Associated findings: ?