Orbit Part 2 Flashcards
What are the cervical ganglion
Superior
Middle
Inferior
How does the sympathetic nerve fibres get from the sympathetic chain to the organs of the head and neck
Preganglionic sympathetic fibres from the spinal cord reach the ganglia of the cervical part of the sympathetic chain by
Exiting the spinal cord in T1 spinal nerve
Travels upward on the sympathetic chain
Synapsids in one of the cervical sympathetic ganglia
To surface of carotid arteries to organs and skin etc
What are the postganglionic sympathetic fibres carried into the cranial cavity
On internal carotid artery distributed via branches including Opthalmic artery to orbit
Also deep petrosal nerve
How are the postganglionic sympathetic fibres carried around extra cranially
External carotid artery and its branches
How are parasymp fibres get form cns to organs
Cns –> preganglionic fibres –> parasymp ganglion synapse ACETYLCHOLINE –> postganglionic fibres ACETYLCHOLINE –> organ
What are the parasympathetic cranial nerves
3
7
9
10
How dos blushing arise
Regions - skin face, ears, neck
Symp supply to skin
Symp vasodilator fibres to facial vein and its tributaries
How is focussing established
Symp - open wider, more light in focus far away
Parasymp - orbicularis oculi, less light in, focus near
How does crying arise
Parasymp secretomotor supply to lacrimal gland
Basal tears flow all the time
Reflex parasymp from facial
Emotional tears from emotional centres
Greater petrosal nerve supply preganglionic fibres parasymp secretomotor to lacrimal gland
How is salivating induced
Parasymp reduce water make saliva sticky
Parasymp secretomotor to parotid via facial
How do sympathetic fibres get from the cns to the organs of the head and neck
Cns –> preganglionic fibres –> cervical part of sympathetic chain ganglion ACETYLCHOLINE –> postganglionic fibre –> organ NORADRENALINE
