Lecture 20 - Ungulate URT 1 Flashcards
nostrils
entrance to the nasal cavity
philtrum
medial deviation ventral to nose
choanae
transition from the nasal cavity into the nasopharynx
what nasal structure is unique to the horse? what is the function?
nasal diverticulum; acts as a “scoop” to draw air in during exercise by expanding the opening
where does the nasolacrimal duct open in horses and donkeys
horse = floor of vestibule
donkey = dorsolateral vestibule wall
atheroma
epidermal inclusion cyst of the diverticulum
“golf ball”
the conchae function to
warm and cleanse-inspired air
what is the largest pathway for a nasogastric tube?
ventral nasal meatus
what is the function of paranasal sinuses
- protection (“crumple zone”)
- immunity
- reduce weight of head
describe the sinuses in the horse
- frontal + dorsal conchal = conchofrontal sinus
- maxillary divided into rostral and caudal components
- sphenopalatine
- ventral, middle, ethmoidal conchal
T/F: as the horse ages, teeth mature and recede from maxillary sinus space
TRUE
T/F: all sinuses drain to the ventral sinus
FALSE - drain to rostral or caudal maxillary sinus
what has a large communication with the caudal maxillary sinus
conchofrontal sinus
what is the pathway in the paranasal sinus for horses
- conchofrontal
- frontomaxillary
- rostral and caudal maxillary
- nasomaxillary
- nasal cavity
where is the conchofrontal trephination site
5cm from the midline on the line of the medial canthus
where is the caudal maxillary sinus trephination
2cm rostral from the rim of the orbit and 2cm ventral to the line of the medial canthus
what are the 3 reasons we trephine
- inspect
- biopsy
- treat
what are the clinical applications of paranasal sinuses
performing a standing sinusotomy to appreciate the space
describe the ox paranasal sinuses
- frontal - divided into caudal (containing post-orbital, nuchal, and cornual diverticula) and rostral
- maxillary w/ lacrimal bulla
- palatine
- sphenoid
where does sinus drainage end in the ox?
nasal cavity
what occurs when horn tipping is done too short
leaves cornual diverticulum open for infection
what is the function of the guttural pouch
cool blood going to the brain and regulate intracranial pressure
why divides the guttural pouch
stylohyoid bone
what is found in the guttural pouch
- CN 9-12
- sympathetic trunk and cranial cervical ganglion
- internal carotid, external carotid, and maxillary a.
- retropharyngeal ln
how do strangles impact the guttural pouch
infects and results in lymphadenomegaly which may compress the upper airway
ln abscess, rupture, and drain into guttural pouch
T/F: diseases affecting the guttural pouch will result in clinical signs consistent with affected structures in the area
TRUE
what are the reasons for severe epistaxis in equines
- compromised artery (guttural pouch mycosis)
- torn muscles (ruptured capitis mm.)
