Autonomic Pathways of the Eye Screencast Flashcards
What are some structures of the head and neck that have autonomic supply?
Skin = arterioles, sweat glands, arrector muscles
Eye = smooth muscle of lens and ciliary body
Lacrimal and salivary glands
Where do sympathetic nerves originate?
Originate from autonomic centres in the brain and pass down the spinal cord
Where do sympathetic axons leave the spinal cord?
Leave with spinal nerves at T1-L2 level (thoracolumbar outflow)
Where does the sympathetic chain run?
The full length of the spinal column
Where do sympathetic axons go to once they leave the sympathetic chain?
Pass into all spinal nerves (anterior and posterior rami) and then into splanchnic nerves to supply organs
What is the route of pre-synaptic sympathetic axons going to the head and neck?
Exit spinal cord in T1 spinal nerve, ascend with sympathetic chain, synapse in superior cervical sympathetic ganglion
What structures do the post-synaptic sympathetic axons pass into?
Internal and external carotid nerves = pass onto surface of internal and external carotid arteries via peri-articular plexus
What carries post-synaptic sympathetic axons to the head and neck?
Branches of the internal and external carotid arteries
What artery carries sympathetic axons into the orbit?
Ophthalmic artery
What do all parasympathetic axons leave the CNS via?
Cranial nerves III, VII, IX and X
Sacral spinal nerves (craniosacral outflow)
What do the parasympathetic ganglia of the head supply?
Eyes, lacrimal gland and salivary gland
What parasympathetic ganglion is associated with the eye?
Ciliary ganglion
What structures does the vagus nerve supply with parasympathetic fibres?
Organs of neck, chest and abdomen as far as the midgut
Where do sacral spinal nerves carry parasympathetic axons to?
Hindgut, pelvis and perineum
Where is the ciliary ganglion located?
Just inside the bony orbit = anterior to the optic canal and superior orbital fissure area
