Lecture 20 - Ungulate URT 1

Question 1

nostrils

Answer 1

entrance to the nasal cavity

Question 2

philtrum

Answer 2

medial deviation ventral to nose

Question 3

choanae

Answer 3

transition from the nasal cavity into the nasopharynx

Question 4

what nasal structure is unique to the horse? what is the function?

Answer 4

nasal diverticulum; acts as a “scoop” to draw air in during exercise by expanding the opening

Question 5

where does the nasolacrimal duct open in horses and donkeys

Answer 5

horse = floor of vestibule
donkey = dorsolateral vestibule wall

Question 6

atheroma

Answer 6

epidermal inclusion cyst of the diverticulum

“golf ball”

Question 7

the conchae function to

Answer 7

warm and cleanse-inspired air

Question 8

what is the largest pathway for a nasogastric tube?

Answer 8

ventral nasal meatus

Question 9

what is the function of paranasal sinuses

Answer 9

1. protection (“crumple zone”)
2. immunity
3. reduce weight of head

Question 10

describe the sinuses in the horse

Answer 10

1. frontal + dorsal conchal = conchofrontal sinus
2. maxillary divided into rostral and caudal components
3. sphenopalatine
4. ventral, middle, ethmoidal conchal

Question 11

T/F: as the horse ages, teeth mature and recede from maxillary sinus space

Answer 11

TRUE

Question 12

T/F: all sinuses drain to the ventral sinus

Answer 12

FALSE - drain to rostral or caudal maxillary sinus

Question 13

what has a large communication with the caudal maxillary sinus

Answer 13

conchofrontal sinus

Question 14

what is the pathway in the paranasal sinus for horses

Answer 14

1. conchofrontal
2. frontomaxillary
3. rostral and caudal maxillary
4. nasomaxillary
5. nasal cavity

Question 15

where is the conchofrontal trephination site

Answer 15

5cm from the midline on the line of the medial canthus

Question 16

where is the caudal maxillary sinus trephination

Answer 16

2cm rostral from the rim of the orbit and 2cm ventral to the line of the medial canthus

Question 17

what are the 3 reasons we trephine

Answer 17

1. inspect
2. biopsy
3. treat

Question 18

what are the clinical applications of paranasal sinuses

Answer 18

performing a standing sinusotomy to appreciate the space

Question 19

describe the ox paranasal sinuses

Answer 19

1. frontal - divided into caudal (containing post-orbital, nuchal, and cornual diverticula) and rostral
2. maxillary w/ lacrimal bulla
3. palatine
4. sphenoid

Question 20

where does sinus drainage end in the ox?

Answer 20

nasal cavity

Question 21

what occurs when horn tipping is done too short

Answer 21

leaves cornual diverticulum open for infection

Question 22

what is the function of the guttural pouch

Answer 22

cool blood going to the brain and regulate intracranial pressure

Question 23

why divides the guttural pouch

Answer 23

stylohyoid bone

Question 24

what is found in the guttural pouch

Answer 24

• CN 9-12
• sympathetic trunk and cranial cervical ganglion
• internal carotid, external carotid, and maxillary a.
• retropharyngeal ln

Question 25

how do strangles impact the guttural pouch

Answer 25

infects and results in lymphadenomegaly which may compress the upper airway

ln abscess, rupture, and drain into guttural pouch

Question 26

T/F: diseases affecting the guttural pouch will result in clinical signs consistent with affected structures in the area

Answer 26

TRUE

Question 27

what are the reasons for severe epistaxis in equines

Answer 27

1. compromised artery (guttural pouch mycosis)
2. torn muscles (ruptured capitis mm.)