Cranial Nerve V (Trigeminal)

Pharmacology / Cardio & Renal / Heart Failure Drugs

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The trigeminal nerve or cranial nerve V has three branches: the ophthalmic nerve (V1, pure sensory), maxillary nerve (V2, pure sensory), and mandibular nerve (V3, motor + sensory). The ophthalmic nerve (V1) and maxillary nerve (V2) pass through the cavernous sinus, with V1 exiting the cranium via the superior orbital fissure and V2 via the foramen rotundum. The ophthalmic nerve covers the upper 1/3 of the face, including the anterior scalp, forehead, upper eyelid, frontal/ethmoid sinus, cornea, lacrimal gland, and superior part of the nose, while the maxillary nerve covers the midface, such as the lower eyelid, cheek, nasopharynx, upper lip/teeth/gums, and palate.

The mandibular nerve (V3) exits the cranium via the foramen ovale and has both motor and sensory components. V3 is responsible for the sensory innervation of the lower 1/3 of the face, including the lower lip, lower teeth/gums, chin, anterior 2/3 of the tongue, and the external auditory canal. It also innervates the muscles of mastication (masseter, temporalis, medial and lateral pterygoids), anterior belly of digastric, mylohyoid, tensor veli palatini, and tensor tympani, which dampens loud noises. The trigeminal ganglion is the sensory ganglion of cranial nerve V.

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1. V shield - Cranial nerve V = trigeminal nerve
2. Terrifying tri-gem serpent - Cranial nerve V = trigeminal nerve
3. Serpent’s body - Trigeminal ganglion is a sensory ganglion of CN V
4. 1 eye + feathers - First branch of CN V = ophthalmic nerve (V1, pure sensory)
5. Cavern - V1 and V2 pass through the cavernous sinus
6. Cracked gem above 1 eye - V1 exits cranium via superior orbital fissure
7. Red face paint - V1 covers the upper 1/3 of face (e.g. anterior scalp, forehead, upper eyelid, frontal/ethmoid sinus, cornea, lacrimal gland, and superior part of nose)
8. Nose hairs extending into 1-eye - Nasociliary branch of V1 → afferent limb of corneal reflex
9. 2 upper fangs + feathers - Second branch of CN V = maxillary nerve (V2, pure sensory)
10. Rotund head - V2 exits cranium via foramen rotundum
11. Green gem + green face paint - V2 covers the midface (e.g. lower eyelid, cheek, nasopharynx, upper lip/teeth/gums, palate)
12. 3 bottom fangs - Third branch of CN V = mandibular nerve (V3, motor + sensory)
13. Chariot - V3 has both motor and sensory components
14. Feathers - V3 has both motor and sensory components
15. Oval scales - V3 exits cranium via foramen ovale
16. Forked tongue - V3 = anterior 2/3 of tongue (pain/sensory)
17. Yellow gem + yellow face paint - V3 covers the lower 1/3 face (e.g. lower lip, lower teeth/gums, and chin)
18. Ear hole - V3 = anterior, inferior and superior regions of external auditory canal (sensory)
19. Serpent munching on Viking - V3 = muscles of mastication (e.g masseter, temporalis, medial and lateral pterygoids), anterior belly of digastric, mylohyoid, and tensor veli palatini (motor)
20. War timpani - V3 = tensor tympani → dampens loud noises (motor)