Sinuses and Horn

Question 1

What are paranasal sinuses

Answer 1

Air filled extensions of the nasal cavity that invaginate into bone

Question 2

What are paranasal sinuses innervated by

Answer 2

Opthalmic and maxillary branches of the trigeminal nerve

Question 3

What sinuses do all species have

Answer 3

Frontal and maxillary sinuses

Question 4

What are the functions of sinuses

Answer 4

• Resonating cavities (voice)
• Insulation/ cooling (brain)
• Light weight construction
• Increased insertion surfaces, space for teeth

Question 5

What does the frontal sinus system consist of in all species

Answer 5

One or more spaces within the bones at the border between the nasal and cranial cavities

Question 6

Where does the maxillary sinus system occupy in all species

Answer 6

The caudolateral part of the upper jaw, above the caudal cheek teeth (molars and premolars)

Question 7

Where does the maxillary sinuses drain into in most species? Why is this drainage difficult?

Answer 7

• Into the middle meatus

- Drainage goes against gravity

Question 8

How many compartments is the frontal sinus system made up of in

• Dogs
• Cattle
• Pigs

Answer 8

Dogs= 3
Cattle= 5
Pigs= 1 extensive cavity

Question 9

Where does the frontal sinus drain into in most species

Answer 9

The ethmoidal region

Question 10

How many individual paranasal sinuses are there in horses

Answer 10

7

Question 11

What common structure do all paranasal sinuses drain via in horses

Answer 11

The ostium/ drainage angle

Question 12

What are the groups that the paranasal sinuses in horses are split into

Answer 12

• Caudal paranasal sinuses (5)

- Rostral paranasal sinuses (2)

Question 13

What are the 5 caudal paranasal sinuses in horses

Answer 13

• Caudal maxillary sinus
• Dorsal conchal sinus
• Ethmoidal sinus
• Frontal sinus
• Sphenopalatine sinus

Question 14

What are the 2 rostral paranasal sinuses in horses

Answer 14

• Rostral maxillary sinus

- Ventral conchal sinus

Question 15

Where is the infraorbital sinus located in birds

Answer 15

Under the skin rostroventral to the eye (triangular cavity)

Question 16

Which sinus system does the nasolacrimal duct run through

Answer 16

Maxillary sinus system

Question 17

Why are horses and ruminants more likely to get maxillary sinus infections compared to domestic species

Answer 17

Due to them having continuously erupting teeth

Question 18

Which sinus is located next to the horn in cattle?

Why is this relevant?

Answer 18

• Frontal sinus

- During dehorning in adults the sinus is exposed resulting in predisposition to infection and nasal discharge

Question 19

Where does the majority of the innervation of horns arise from

Answer 19

Trigeminal nerve

Question 20

As well as the trigeminal nerve, what nerve innervates the horn in all animals

Answer 20

Cornual nerve

Question 21

What nerves need to be blocked when dehorning calves

Answer 21

Corneal nerve

Question 22

What nerves need to be blocked when dehorning adult cattle

Answer 22

• Corneal nerve
• corneal branch of infratrochlear nerve
• May also need to block region caudal to horn

Question 23

Why do you need to be careful when dehorning goat kids

Answer 23

Frontal sinus is very small and excess heat can damage the brain

Question 24

What arteries supply the horn in ruminants

Answer 24

• Corneal artery
• Which is a branch of superficial temporal artery
• Which is a branch of maxillary artery

Question 25

What does unilateral nasal discharge usually represent

Answer 25

• Upper respiratory tract infection (bacterial or fungal)
• Nasal disease
• Sinus disease= sinuses drain into nasal cavities

Question 26

What does bilateral nasal discharge usually mean

Answer 26

• bilateral upper airway disease

- lower airway disease- caudal to the pharynx/larynx