Sympathetic sypply to head and neck L8 Flashcards
what is the origin and relay for the sympathetic sypply to the head and neck?
origin: T1 , T2
relay: superior cervical ganglion (scg)
Enumerate the effects of the sympathetic nervous system on the eye :
- contraction of dilator pupillae ms → mydriasis
- contraction of tarsal ms → widening of palpberal fissure
- contractoin of muller’s ms → exophthalmos
- relaxation of ciliary ms → ↓ convexity of lens → see far objects
- vasoconstriction of blood vessels of lacrimal gland → trophic secretion
what are the characteristics of trohpic secretion?
little, viscous, concentrated, poor in water & rich in enzymes
Enumerate the effects of the sympathetic nervous system on the salivary glands :
- V.C of salivary glands blood vessels.
- trophic secretion
- contraction of myoepithelial cells surrounding the salivary acini → squeezing the salivary secretion outside.
Enumerate the effects of the sympathetic nervous system on the skin:
- V.C & V.D but vasoconstriction is more powerful.
- sweat secretion.
- contraction of piloerector ms → hair erection
what’s the effect of sympathetic NS on cerebral blood vessels?
Mild vasoconstriction
Define horner’s syndrome:
set of signs which result from interruption of sympathetic to head and neck.
what are the causes of horner’s syndrome?
- lesion in T1, T2
- lesion in superior cervical ganallion
Enumerate the signs of horner’s syndrome:
- ptosis
- miosis
- anhydrosis
- vasodilation
- enophthalmos
what happens when paralysis occure in superior tarsal ms?
ptosis (dropping of uper eye lid)
what happens when paralysis occure in dilatorpupillae ms?
miosis (contraction of pupil)
what happens when paralysis occure in muller’s ms?
enophthalmos (sinking of eye ball into orbit)
V.I.P: where does horner’s syndrome occur?
in the same side of the lesion
