Anatomy: Intro to Cranial Nerves Flashcards
CN I
- Olfactory Nerve
- sensory- sense of smell
- Runs from the nasal mucosa (roof of nasal cavity along medial side of superior nasal concha
- Olfactory Organ - collection of epithelium
- Coalesce into filia olfactoria (olfactory fibers; these are the actual CN I)- these pass through cirbiform foramina
- Synapse on mitral cells in the bulb, project to forebrain via olfactory tract
Olfactory bulb and tract are part of what?
The brain, they are not actually the cranial nerve. The filia olfactoria are the nerves, which pass through the cribiform foramina and converge on bulb.
Olfactory tract projects where?
Forebrain, particualry limbic system- emotions, memory, visceral reflexes
Link between smells and memories/emotions
anosmia
- loss of smell
- commonly arises from nasal infections and ethmoid fractures
CN II
- Function- sensory for vision, various reflexes
- Course- ganglion cell fibers from retina join to form optic nerve, through optic canals and meet at optic chiasma, medial fibers dessucate, then to **Lateral Geniculate Nucleus of Thalamus **
CN IV
- Trochlear Nerve
- innervates Superior Oblique Muscle
- Passes through **Superior Orbital Fissure **
- Projects from Midbrain (pons) posteriorly and wraps around
CN V
- **Trigeminal Nerve **
- Projects from Pons (oversimplified)
- Trigeminal Ganglion- sensory ganglion on anterior surface of petrous part of temporal bone
Three Divisions
1. Opthalmic (CN V 1)
2. Maxillary (CN V2)
3. Mandibular (CN V3)
- From trigeminal ganglion (sensory ganglion)
Opthalmic Nerve
- CN V1
- sensory to face, orbital contents, scalp, sinues, dura
- through superior oribital fissure
Maxillary Nerve
- CN V2
- sensory to face, nasal cavities, palate, maxillary teeth and sinus, dura
- passes through foramen rotundum and pterygopalatine fossa
Mandibular Nerve
- CN V3
- Passes through Foramen Ovale to infratemporal Region
- Sensory to face, temporomandibular joint, mandibular teeth, tongue (ant 2/3), mouth, dura
- motor to muscles of mastication (also others)
Standing Room Only
S. Superior Orbital Fissue (opthalmic)
R. Foramen Rotundum (Maxillary)
O. Forarmen Ovale (Mandible)
Trigeminal Ganglion
sensory ganglion located on anterior surface of petrous part of
temporal bone in the trigeminal cave
Facial Nerve
Opthalmic Nerve
CN V 1
sensory from orbital, parts of face, scalp, nasal cavity, sinuses, dura
passes through superior orbital fissure
standing room only
Maxillary nerve
Sensory to parts of face, nasal cavities, palate, maxillary teeth, mxillary sinus, and dura
passes through foramen rotundum and pterygopalatine fossa
standing room only (Foramen Rotunda)