Skull, Mandible, and Hyoid Apparatus Flashcards
dolichocephalic
whippet/greyhound shape (long nosed dogs)
mesocephalic
medium-nosed dog
brachycephalic
short nosed dog
Skull
complex of bones formed in both membrane and cartilage
cranium
bones that surround the brain
calvaria
roof of the cranium (parietal and frontal bones)
external sagittal crest
median ridge formed by parietal and interparietal bones
Do all breeds have an external sagittal crest?
No - brachycephalic breeds often do not
Temporal line
present in all breeds, most pronounced in brachycephalics; not associated with temporal bone
temporal fossa
External occipital protuberance
where interparietal and occipital bone fuse
Paracondylar process
ventral projections that articulate with tympanic bulla
Occipital condyles
protrusions help outline foramen magnum
Pink?
Green?
Blue?
Pink = External occipital protuberance
Green = Occipital condyles
Blue = Paracondylar process
Foramen Magnum
exit for the medulla of the brainstem to the spinal cord
Hypoglossal canal
exit for hypoglossal nerve (CN12)
What cranial nerves run through the tympano-occipital fissure?
CN9, 10, and 11 (glossopharyngeal, vagus, accessory)
Species with the tympano-occipital fissure
carnivore and ruminant
Structures that are not cranial nerves that go through tympano-occipital fissure
internal jugular vein, sympathetic and parasympathetic postganglionic axons [from the cranial cervical ganglion]
Nuchal crest
the point where you go from dorsal surface to caudal surface of the skull; in the carnivore and equine
Nuchal line
in the ruminant, frontal bone goes to the caudal aspect
Ethmoid foramen
at ventrolateral aspect of the frontal bone and the ethmoid vessels run through it
Is the zygomatic process of the frontal bone present in all three species?
yes
Supraorbital Foramen
palpable formen in the equine frontal bone where the supraorbital VAN triad goes though and is important for nerve blocks