Trigeminal Nerve Flashcards
What are the 3 divisions of the trigeminal nerve
Opthalmic nerve - Va
Maxillary nerve - Vb
Mandibular nerve - Vc
What are the exit points of each division of the trigeminal nerve
Va - supra-orbital notch (foramen)
Vb - intra-orbital foramen
VF - Mental foramen
What bones compose the hard palate
Maxilla
Palatine
Where does the trigeminal pass through the soft palate
Incisive foramen
Greater palatine foramen (paired)
Lesser palatine foramen (paired)
What are the processes of the mandible
Coronoid process
Condylar process
Where does the trigeminal nerve emerge from the brain
The pons
How many roots does the trigeminal nerve have
2 - sensory and motor
Describe the information coming from the motor nucleus of the trigeminal and where does it go
Special visceral efferent information to the muscles of mastication
Describe the information going to the sensory nuclei of the trigeminal nerve
General somatic afferent
What are the different sensory nuclei of the trigeminal nerve and where in the brainstem are they found
Mesencephalic nucleus in the midbrain
Chief sensory nucleus in the pons
Spinal nucleus in the medulla
What is the function of the mesencephalic nucleus
Proprioception
What is the function of the chief sensory nucleus
Discriminative touch
What is the function of the spinal nucleus
Pain and temperature for structures supplied by the trigeminal as well as general conscious sensation for the viscera supplied by the glossopharyngeal and vagus nerves
Where do the trigeminal nerve roots travel
Emerge from the mid-pons and pass forwards onto the apex of the patrols temporal bone where the trigeminal ganglion lies in a cave of dura mater (Meckel’s cave)
What is Meckel’s cave
A cave in the dura mater where the trigeminal ganglion is found
Where does CN Va pass from the trigeminal ganglion
Anteriorly in the lateral wall of the cavernous sinus to reach the superior orbital fissure
Where does CN Vb pass from the trigeminal ganglion
Anteriorly in the lateral wall of the cavernous sinus to reach the pterygopalatine fossa via the foramen rotundum
Where does CN Vc pass from the trigeminal ganglion
Through the foramen ovale
If all 3 divisions of the trigeminal nerve are affected by a lesion, where must it be
In the pons - stroke
At the cranial base - trauma or tumour
Which other nerves are commonly affected if there is a problem in the trigeminal nerve
CN III and CN IV
What are the main branches of the opthalmic division of the trigeminal
Frontal
Lacrimal
Nasociliary
Describe the path of the frontal nerve and what it supplies
Divides into the supraorbital and supratrochlear nerves which supply the skin of the vertex and upper eyelid and forehead
What does the lacrimal nerve supply
The lacrimal gland, skin of the upper eyelid and forehead
What does the nasociliary nerve branch into and what does this supply
Gives off long ciliary nerves - anterior and posterior ethmoidal nerves, before continuing as the infratrochlear nerve which supplies the skin of the medial upper eyelid and root of the nose
Anterior ethmoidal nerve continues into the external nasal nerve