Anatomy Ii - Head (Equine)

Front 1

What is a Meatus? Name them

Back 1

a natural body opening or canal
(dorsal, middle, ventral)

Front 2

What is a Concha?

Name them

Back 2

Nasal concha (or turbinate) is a long, narrow and curled bone shelf (shaped like an elongated sea-shell) which protrudes into the breathing passage of the nose. Turbinate bone refers to any of the scrolled spongy bones of the nasal passages in vertebrates.

Front 3

which conchae is associated with frontal sinus?

Back 3

dorsal concha

Front 4

Surgical limit of maxillary sinus:
Rostrally? Caudally?

Back 4

Rostrally: a vertical line through the infraorbital foramen.

Caudally: a vertical line through the middle of the eye.

Front 5

Surgical limit of maxillary sinus:
Dorsally? Ventrally?

Back 5

Dorsally: a line from the infraorbital foramen to eye.

Ventrally: border along facial crest

Front 6

Viborg’s triangle: 3 boundaries (clinical significance)
a. rostral border?
b. ventral border?
c. dorsocaudal border?

Back 6

a. Rostral – caudal margin (ramus) of the mandible
b. Ventral – linguofacial vein
c. Dorsocaudal – tendon of insertion of sternocephalicus muscle

* One of the approaches to the guttural pouch for surgical intervention.

Front 7

Site of surgical entry into guttural pouch:

Back 7

Viborg's triangle

Front 8

• Parotidoauricularis muscle covers ?

Back 8

Parotidoauricularis muscle covers the parotid gland (check on this)

(important in operations for drainage of infections of external ear in dog)

Front 9

Pupil of horse is normally

Back 9

transversely oblique in shape

Front 10

The master lymph node of the head of the horse is the :

Back 10

- medial retropharyngeal

Front 11

There is a bony plate that divides the maxillary sinus into medial and lateral parts, what canal is transmitted through this bony plate?

Back 11

transmits the infraorbital canal on its dorsal border

Front 12

A long bony ridge on the lateral part of the head of the horse that is an important practical or clinical landmark is:

Back 12

facial crest

Front 13

In the horse vomit passes through nasal cavity because?
(check on this)

Back 13

- long soft palate separates the oropharynx from the nasopharynx

(but i thought horses can't vomit?)

Front 14

The following muscle is unique to the horse:
oc____ muscle

Back 14

occipitomandibularis muscle
(don't confuse with digastricus m.)

Front 15

Links the frontal sinus directly with the (caudal) maxillary sinus.

Back 15

frontomaxillary opening

Front 16

Which roots of the upper cheek teeth project into maxillary sinus in the horse?

Back 16

- last 2 or 3

Front 17

Name 2 important canals that pass through or close to maxillary sinus of the horse

Back 17

nasolacrimal canal - runs on dorsolateral aspect of maxillary sinus
infraorbital canal -

Front 18

True or False: concerning the maxillary sinus of the horse
- it has 2 main divisions (rostral and caudal)?

Back 18

True

Front 19

The frontal sinus of the horse communicates with the nasal cavity how?

Back 19

- indirectly through the maxillary sinus

Front 20

Main bone which forms roof of the cranium of the horse:

Back 20

parietal

Front 21

Concerning the azygos vein of the horse, what side(s) can it be found on?

Back 21

- it is only present on the right

Front 22

The roof of the equine cranium is formed by the _?

(in ruminant?)

Back 22

The roof of the cranium is formed by the occipital, parietal and interparietal bones, and rostrally, by the frontal bones.

(c.f. ox – the cranium is formed by the frontal bone which displaces the parietal bones, laterally and caudally)

Front 23

from ext. occipital prot. runs cranially , in the midline, diverges to form the temporal line, on either side, before joining the zygomatic process of the frontal bone.

Back 23

external saggital crest

diverges to form the temporal line, on either side, before joining the zygomatic process of the frontal bone.
(not in ruminants)

Front 24

_____ pierces the root of the zygomatic process of the frontal bone

Back 24

supraorbital foramen

pierces the root of the zygomatic process of the frontal bone

Front 25

occipital bone forms most of the caudal part of the skull, and it projects DORSALLY to form the ____?

Back 25

form the nuchal crest

Front 26

Prominent ridge on lateral portion of skull – ______, a major landmark

Back 26

the facial crest

Front 27

_______ lies between the nasal and incisive bones

Back 27

nasoincisive notch lies between the nasal and incisive bones

Front 28

separates cranial cavity (cerebrum) from caudal part (cerebellum)

Back 28

tentorium cerebelli osseum

Front 29

The external nose is supported:
Rostrally?
Laterally?
Dorsally, medially and ventrally?

Back 29

Rostrally, by the median nasal septum,
Laterally, by dorsolateral nasal cartilage
Dorsally, medially and ventrally, by the alar cartilage

Front 30

_____ comprises a dorsal, flat and broad lamina, and a narrow, curved ventral cornu (horn).

Back 30

Alar cartilage

Front 31

T/F Laterally, the nostril has cartilaginous support via dorsolateral nasal cartilage.

Back 31

False: that supports lateral nose, not the nostril itself

Laterally, the nostril has no cartilaginous support.

Front 32

large, oval, opening - in floor of frontal sinus, and situated between the median plane (huh?) and the orbit.

Back 32

frontomaxillary opening

Front 33

Identify

Back 33

see pic

Front 34

essentially and developmentally, invaginations of the nasal mucosa into the bones

Back 34

PARANASAL SINUSES

Front 35

nasal mucosa innervation

Back 35

ophthalmic and maxillary br. of trigeminal n.?

Front 36

bone found only in horse and cat btw 2 parietal bones, rostral to occipital bone.

Back 36

Interparietal bone

Front 37

T/F Bony orbit is complete in ruminants but not horse

Back 37

False complete in horse and ruminant, NOT in carnivores

Front 38

All permanent horse teeth are ?

Back 38

hypsodont

All equine teeth, except canine and P1, are hypsodont (erupt throughout life) and cheek teeth are anisognathous.

Cheek teeth?

Front 39

Duct running from parotid gland to oral cavity?
(if you get this wrong, drop out of vet school!)

Back 39

parotid duct

Front 40

Masseter muscle is dominant in ?

Back 40

in herbivore

origin on maxillary region and zygomatic arch, insert on caudal part of mandible; adapted for chewing and small lateral mov't

Front 41

Temporalis muscle is dominant in ?

Back 41

in carnivore!
higher on head (frontal bone and temporal fossa) than masseter, also covers coronoid process on mandible

therefore better for scissorlike mov't or biting

Front 42

Muscles of mastication (4 and 1 extra)

Back 42

temporalis, MASSETER, pterygoideus medialis/lateralis

~digastricus helps open mouth, it is on ventral portion of mandible, caudal to T/M joint

Front 43

Comparatively, frontal bone what size in equine (in proportion to its skull, etc.)?

Back 43

Frontal is smaller in equine, b/c it is rostral to temporal fossa and temporal line.
Largest in ruminant

Front 44

name for 1st premolars which usually do not develop, but if present are in UPPER archade, and smallish

Back 44

wolf teeth

note: dental formulas P 3/3 shown in next question does not include wolf tooth, but wolf tooth is always PM1; if name specific premolar e.g. premolar after wolf is called PM2 even if wolf not present.

Front 45

Permanent Dental Formula in horse

Back 45

Incisor 3/3
C1/1 (male only, sometimes in female but appear under- developed)
P3/3
M3/3
X 2 (for left and right)= 40 teeth total)

Front 46

* Masticatory / occlusal surface / table is flat, and changes shape with age, from oval, rounded, triangular and back to oval.
* For cropping/cutting of grass

Back 46

Incisors

Front 47

identify

name for masticatory surface?

Back 47

1. External Enamel
2. Central Enamel
3. Cement
4. Dentine
5. Dental Cavity
6. Infundibulum dentis
>masticatory surface known as "occlusal surface"

Front 48

What is the central cleft of incisor teeth?

Back 48

Central cleft – infundibulum, lined by cementum.
(yellow)

Front 49

Where is the site of the pulp cavity, where the darker, secondary dentine has been laid down in the incisors?

Back 49

Dental star

infundibulum gradually filled in by secondary dentine (occludes central cavity)

Front 50

What side of the lower cheek teeth wear faster?

Back 50

Vestibular side wear faster than lingual side

Front 51

What side fo the upper cheek teeth wear faster?

Back 51

Lingual side (inner surface) wear faster than vestibular side in upper teeth

Front 52

sphenopalatine and middle conchal sinuses both drain into the ?

Back 52

sphenopalatine and middle conchal sinuses both drain into the "caudal maxillary sinus"

Front 53

Only the _____ sinuses communicate directly with the nasal cavity

Back 53

Only the communicate directly with the nasal cavity

Front 54

Both (cranial and caudal) maxillary sinuses open into _____ through the ______?

Back 54

Both (cranial and caudal) maxillary sinuses open into:
the nasal cavity (middle nasal meatus) through the common, slit-like nasomaxillary opening,

Front 55

difference betw. frontal sinus and conchofrontal sinus

Back 55

see pic

Front 56

rostral and caudal maxillary sinuses are seperated by ?

direct communication btw. ?

Back 56

oblique septum

therefore no direct communication btw. the two

Front 57

Dr Aires said "rostral part of maxillary sinus incorporates ____?"

Back 57

rostral part of max.sinus incorporates the caudal part of ventral conchae

Front 58

which part of maxillary sinus is larger?

Back 58

caudal part

Front 59

What must be careful of when removing last 3 or 4 cheek teeth which project into maxillary sinus?

Back 59

cutting infraorbital canal (infraorbital nerve), runs parallel to facial crest

Front 60

runs on dorsolateral aspect of maxillary sinus?

Back 60

nasolacrimal

Front 61

Inflammation of nasal mucosa of maxillary sinus can occlude the ____?

Back 61

nasomaxillary opening (narrow slit)

Front 62

why must horse eat with head at ground level?

Back 62

to ensure adequate drainage maxillary sinus

because floor of MS in below nasomaxillary opening

Front 63

innervates occipitomandibulatris m?

origin?
insertion?

Back 63

facial nerve

paracondylar process
caudal border of mandible

Front 64

Which tooth erupts first i1 or i3?

Back 64

generally I1 emerge first, I3 last of incisors to develop

therefore I3 (on bottom) often used for age determination

Front 65

what separates the cranial half of the ventral turbinate from the caudal, sinusal half?

Back 65

Complete, bony septum

Front 66

What does abnormal pigmentation of the tongue in a horse mean?

Back 66

Indicative of a malignant tumor

Front 67

What dorsal, palpable cartilagenous cord is present in the median plane of the horses oral cavity?

Back 67

Dorsal lingual cartilage

Front 68

What forms the clinical root in hypsodont teeth?

Back 68

Reserve crown + true root = clinical root

(Reserve crown is proximal part near socket)

Front 69

Very long crowns of hypsodont teeth
the distal part above gum line =

Back 69

distal part above gum line = clinical crown

Front 70

Enamel forms raised ridges on the cutting surface.

Back 70

(enamel crests)

Front 71

What side of the lower cheek teeth wear faster?

Back 71

Vestibular (outer) side wear faster than lingual side

Front 72

What side fo the upper cheek teeth wear faster?

Back 72

Lingual (inner) side wear faster than vestibular side

Front 73

I1 emerges after?
I2 emerges after?
I3 emerges after?

Back 73

I1 emerges after 2.5 yrs.
I2 emerges after 3.5 yrs.
I3 emerges after 4.5 yrs.

Front 74

1. What 3 bones form the hard palate?

Back 74

The hard palate is formed by the maxillary, palatine, and incisive bones.

Front 75

The frontal sinus communicates with what two sinuses?

Back 75

The frontal sinus communicates with the caudal maxillary sinus and dorsal conchal sinus.

Front 76

What 3 muscles are used to close the jaw?

Back 76

Pterygoid, masseter, and temporalis muscles close the jaw.

Front 77

What age do cups wear down?

Back 77

Mandibular:
* first cup to wear down is mandibular I1 at 6 years.
* I2 cup gone at 7 years
* I3 cup is gone at 8 years.

Front 78

Lower incisors flat after ?

Incisors level after?

Back 78

5 years

7 years

(check these numbers)

Front 79

Guestimate age based on picture

Back 79

on exam always say approximately

Front 80

Dental star presence first appears in upper corner incisor at?

Back 80

7-year hook (upper corner),

(according to colostate.edu says dental star first appears on I1 at 8 yrs. maybe on bottom)

Front 81

Galvayne's groove (on upper corner, etc.) appears at?

Back 81

Galvayne’s groove appears on the third incisor at age 10

Front 82

Galvayne's groove disappears over time; what age is half gone?

what age is groove completely gone?

Back 82

age 15


age 30

Front 83

What is the reason that sharp edges and points develop in cheek teeth?
How is this fixed????

Back 83

Differential wearing of teeth surfaces, fixed by floating

Front 84

Where can a swelling of the guttural pouch be palpated on the horse?

Back 84

In the Viborg's triangle

Front 85

62. What shape is a new tooth? What are the next 3 successive shapes and at what ages?

Back 85

New tooth: oval. 10 years: round. 16 years: triangle. 20 + years: oval

Front 86

63. What causes uneven wear in equine teeth? Where do the sharp points form on the mandibular and maxillary teeth?

Back 86

The lower jaw is narrower than the upper jaw, causing uneven wear. Sharp points form on the lingual side of the mandibular cheek teeth and on the buccal side of the maxillary cheek teeth.

Front 87

What are the possible reasons that the parotid region of the horse may be inflamed?

Back 87

Swollen medial retropharyngeal lymph node
Accumulation of secretory material in guttural pouch
Air

Front 88

intubation are difficult b/c ?


how done?

Back 88

* mouth doesnt open wide, narrow rima oris
(commisure more rostral than dog)
* done blindly
* extend head slightly to align axis

Front 89

23. What is “crib-biting”,

Back 89

Also known as wind-sucking. When bored prone to vices. Flexes neck and tenses caudo-ventral hyoid and sternocephalic muscles.

pharynx dilated and animal swallows air

Front 90

how do you correct this “crib-biting”,?

Back 90

resecting the omohyoid, sternocephalic, and sternothyroid muscles

also have collars can put on horse

Front 91

What structures make contact with the roof of the guttural pouch?

Back 91

Foramen lacerum
Tympanic bulla
Cranial nerves 9-12
Chorda tympani
Cranial cervical ganglion
Internal carotid artery

Front 92

What two spaces does the auditive tube connect?

Back 92

Middle ear
Nasopharynx

Front 93

How fast does air move through the larynx during physical exertion in the horse?

Back 93

180 km/h

Front 94

Where does the duct of the mandibular salivary gland open into?

Back 94

Sublingual caruncle

Front 95

Why is the horse an obligatory nasal breather?

Back 95

Soft palate of horse is long and wraps around base of epiglottis
Can only raise it to swallow

Front 96

What is the ventrocaudal diverticulum/evagination of the auditive tube that is only in the horse?

Back 96

Guttural pouch

Front 97

In the larynx what fills the gap formed by incomplete thryroid cartilage?

Back 97

Cricothyroid membrane

Front 98

What is the name of the laryngeal entrance?

Back 98

Aditus laryngis

Front 99

What is the term for the deep, blind mucosal sac in the lateral wall of the larynx? Where is it's opening?

Back 99

Laryngeal ventricle, opens between the vestibular and vocal folds

Front 100

What is the respiratory rate of a horse at rest?

Back 100

8-12 per minute

Front 101

What is the respiratory rate of a horse during physical exertion?

Back 101

About 150 per minute

Front 102

What processes take place during physical exertion to ensure the horse gets enough air?

Back 102

Nostrils dilate maximally
Vasoconstriction of cavernous tissue
Arytenoid cartilages are maximally abducted
Vestibular and vocal folds are in full abduction

Front 103

how is roaring in horse corrected; like what procedure called?

Back 103

ventriculectomy
- remove laryngeal ventricle to widen lumen

Front 104

What is the function of the granula iridica of the eye in the horse?

Back 104

Produce aqueous humor
Protect eye from bright light (cast shadows on retina)

Front 105

T/F Third eyelid not found in horse?

Back 105

False; being an ungulate third eyelidis well developed.

Front 106

What veins form the linguofacial vein?

This vein feeds INTO what ??????????????

Back 106

Facial veins
Lingual veins

In the horse, both the facial and lingual v. form tributary (linguofacial vein). of the external jugular vein

Front 107

What veins help in assisting venous return from head?

Back 107

Veins running through masseter muscle
1. Transverse facial vein (joins the facial vein, rostrally)
2. Deep facial vein (enlarges to become the deep facial vein sinus)
3. Buccal vein

Front 108

Arises in pterygopalatine fossa, and drains the nasal cavity, palate, periorbita, etc.

Back 108

deep facial vein.

~deep to the masseter muscle.

Front 109

What vein is enlarged below the facial crest to form the transverse facial vein sinus?

Back 109

Transverse facial vein

Front 110

What are the lymph nodes of the horse head?

Back 110

Parotid lymph node
Mandibular lymph node
Lateral and medial retropharyngeal lymph nodes

Front 111

What is relationship between parotid and mandibular and retropharyngeal L.N.?

Back 111

efferents from parotid and mandibular empty into retropharyngeal L.N.

Front 112

What structures does the parotid lymph node drain and where do its efferents go?

Back 112

Drains eye, ear, lips, rostral and dorsal superficial muscles
Efferents go to the retropharyngeal lymph node

Front 113

Relationship between Lateral and medial retropharyngeal lymph nodes

Back 113

lateral R/Ph drains into medial R/Ph

Front 114

What does mandibular drain?

Back 114

Drain all areas NOT drained by the parotid ln.: nostrils, palate, tongue and jaws
Efferents go to retropharyngeal lnn. and cranial deep cervical lnn.

Front 115

How many rows of mandibular L.N are there?

Back 115

2

Front 116

Drain deep parts pf the head

Back 116

Lateral retropharyngeal lnn

Efferents go to medial retropharyngeal lnn, cranial deep cervical and tracheal duct.

Front 117

A chain of lnn. along the external carotid artery on the lateral wall of the guttural pouch, and medial to the occipito-mandibularis muscle

Back 117

Lateral retropharyngeal lnn

Front 118

Efferents on what lymph node anastomose to form the tracheal duct.?

Back 118

Medial retropharyngeal lnn.:

Front 119

What do the two rows of the mandibular lymph node form?

Back 119

V shape

Front 120

What do minor salivary glands secrete?

Back 120

Mucous secretions

Front 121

What do major salivary glands secrete?

Back 121

Serous or serous-mucous secretions

Front 122

What side of the larynx is usually paralyzed in roaring in the horse?

Back 122

Left

Front 123

How do you enter the laryngeal ventricle in a ventriculectomy operation?

Back 123

Through the cricothyroid membrane

Front 124

Where is the most common site of damage for the facial nerve?

Back 124

Over the caudal border of the mandible
Where the buccal branches run over the masseter muscle

Front 125

What are some negative effects of facial nerve paralysis?

Back 125

Nostrils cannot dilate
Blink reflex lost
Eyelids cannot close
Lower lid droops
Ear hangs and pulled back
Prehension of lips impeded
Drinking is impeded

Front 126

What is a consequence of bilateral paralysis of the mandibular nerve?

Back 126

Lower jaw drops

Front 127

What nerve must you block to anesthetize all teeth of the maxilla?

Name for this nerve block?

Back 127

Maxillary nerve (Peterson block)

Front 128

What nerve must you block to anesthetize all teeth of the mandible?

Back 128

Inferior alveolar nerve

Front 129

T/F Sublingual salivary gland is monostomatic.

Back 129

False; Sublingual, a minor sal.gland – has only the minor, polystomatic portion.