Unit 2 Flashcards
ankylosis of temporohyoid joint causes
temporal bone fracture to occur
what is the cause of fusion of temporohyoid
not clear
what are the clinical signs of fusion of the temporohyoid fusion (ankylosis)
difficulty chewing
pain
facial and/or vestibular nerve dysfunction
what animals does ankylosis of temporohyoid occur in
adult horses (although has been reported in a 1 year old)
in temporohyoid ankylosis, you have marked enlargement of _____
stylohyoid bone
what is the treatment of temporohyoid ankylosis
surgical partial stylohyoidectomy; ceratohyoidectomy
in surgical repair of temporohyoid ankylosis, where is the incision made
ventral throat latch area
what structures are subject to damage during surgical repair of temporohyoid ankylosis
hypoglossal nerve and lingual artery
what are paranasal sinuses
diverticula of nasal cavity
how are paranasal sinuses formed
during development, spaces in bone hollow out the bone; creating inner and outer plates of bone
sinuses continue to develop as skull matures; development is completed _______
postnatally
what are the paranasal sinuses filled with
air; surfaces lined with mucosae
paranasal sinus communication of the horse
all sinuses communicate with nasal cavity either directly or indirectly through the middle nasal meatus
paranasal sinus communication of the ruminant
paransal sinuses communicate with nasal cavity directly or indirectly through the middle nasal meatus or the sinuses communicate with ethomoid meatuses in the caudal nasal cavity
openings into and out of the sinuses
narrow and easily blocked (fluid no longer can pass out of the sinus)
sinuses are susceptible to infection from what sources
from nasal cavity
from alveolar spaces (teeth)
what are the possible functions of the paranasal sinuses
- enlarge skull areas available for muscular attachment and to make room for large teeth without increasing weight of head
- thermal and mechanical protection
- moisten air
- affect resonance of the voice
what paransal sinuses does the dog have
frontal and maxillary
what paranasal sinuses does the horse have
frontal maxillary palatine sphenoid conchal
what paranasal sinuses does the ox have
frontal maxillary lacrimal palatine (large) sphenoid conchal *same in ruminants, but smaller palatine*
where is the frontal sinus located in the horse
between internal and external plates of frontal bone
frontal sinus of the horse is separated into what
right and left sinuses by a bony median septum
what are the rostral extensions of the frontal sinus in the horse
from level of temporomandibular joint to beyond the orbit;
what are the lateral extensions of the frontal sinus in the horse
into zygomatic process of frontal bone
frontal sinus is continous rostromedially with ________
dorsal conchal sinus (together called the conchofrontal sinus)
is there an opening of conchofrontal sinus into nasal cavity
no direct opening into nasal cavity
frontal sinus communicates with the caudal maxillary sinus via the
frontomaxillary opening
where is the frontomaxillary opening in the horse located
between the medial angle of the eye and the median plane
what is the caudal surgical boundary (horse) of the conchofrontal sinus
transverse plan through zygomatic process of frontal bone
what is the rostral surgical boundary (horse) of the conchofrontal sinus
transverse plane midway between rostral margin of the orbit and infraorbital foramen
what is the medial surgical boundary (horse) of the conchofrontal sinus
line 2 cm lateral and parallel to the dorsal midline
what is the lateral surgical boundary of the conchofrontal sinus (horse)
line connecting supraorbital foramen with rostral end of medial limit
what is the largest sinus in the horse
maxillary
maxillary sinus of the horse is divided into what parts
rostral and caudal sinuses (no communication between the two)
caudal maxillary sinus extends caudally to _____
medial side of orbit
rostral and caudal maxillary sinuses are separated by ______
“oblique” osseous septum; located ~5 cm caudal to rostral extend of facial crest
what causes an upward bulge of ventral floor of the maxillary sinus to an extend that varies with age
some cheek teeth
teeth are covered by
thin plate of bone that separates teeth roots from maxillary sinus space
in the foal, the maxillary sinus is largely occupied by the
developing teeth; sinus is located dorsal to facial crest
teeth move ____somewhat with age
rostrally
as the skull matures, the sunus extends _____ as the teeth erupt and the roots move more _____
ventrally; ventrallly
rostral and caudal maxillary sinuses communicate with the middle nasal meatus via the
nasomaxillary opening
rostral maxillary sinus of the horse communicates medially with the
ventral conchal sinus over the infraorbital canal
caudal maxillary sinus is divided by _____ into medial and lateral parts (just call both caudal max. sinus)
infraorbital canal
caudal maxillary sinus communicates with the frontal sinus via the
frontomaxillary opening
caudal maxillary sinus communcates with middle nasal meatus via the
nasomaxillary opening
caudal maxillary sinus also communicates with
sphenopalatine sinus and middle conchal sinus
what is the caudal surgical boundary (horse) of the maxillary sinus
rostral border of the orbit
what is the rostral boundary of the of the maxillary sinus (horse)
line from the rostral end of the facial crest to the infraorbital foramen
what is the ventral boundary of the maxillary sinus in the horse
facial crest
what is the dorsal boundary of the maxillary sinus in the horse
line from infraorbital foramen parallel to the facial crest
when performing surgery on maxillary sinus, avoid damaging the ______
nasolacrimal duct
what is the very large sinus in the ox
frontal sinus
what is the rostral limit of the frontal sinus of ox
transverse plane through rostral margins of orbits
frontal sinus involves most of _____
frontal bone
frontal sinus left and right halves are completely separeted by _____ in the ox
median septum
what are the two compartments of the frontal sinus of the ox
large caudal frontal sinus and 2 or 3 rostral frontal sinuses
each compartment opens separately and directly into the
caudal middle nasal meatus, through an ethmoidal meatus
nuchal diverticulum of ox
in caudal wall of the skull
postorbital diverticulum of ox
caudal to the orbit
cornual diverticulum of ox
within the cornual process
trephination of caudal frontal sinus of ox
place hole at a transverse line through the caudal border of the orbits and approximately 2-3 cm (1.4 inches) away from midline) avoid frontal vein*
trephination of diverticulae of the caudal frontal sinus
nuchal diverticulum
postorbital diverticulum
trephination of diverticulae of the rosral forntal sinus
rosrolateral part
rostromedial part
is the maxillary sinus in the ox divided?
no
maxillary sinus in ox extends rostral to level of
facial tuberosity
what is the caudal extend of the maxillary sinus
lacrimal bulla
what are immediately ventral to the maxillary sinus
3rd or 4th cheek teeth roots are covered by thin plate of bone
maxillary sinus communicates freely with _____ in ox
palatine sinus over the infraorbital canal
communicates with the middle nasal meatus via
large nasomaxillary opening
trephination of maxillary sinus in ox over one year of age
trephine just dorsal and caudal to the facial tuberosity
trephination of maxillary sinus in ox under one year of age
approximately one inch farther dorsally than the previous site; sinus is not extensive
palatine sinus of ox excavation in
hard palate
palatine sinus communicates with the _____ sinus
maxillary sinus over the infraorbital canal
palatine sinus of ox also communcates with
middle nasal meatus
lateral compartment of frontal sinus in sheep and goats
large and more caudal
frontal sinus is more extensive in _____ breeds
horned; may extend into cornual process
medial compartment of frontal sinus in goat and sheep
small (1 or 2 parts)
maxillary sinus in sheep and goat is divided by
infraorbital canal into medial and lateral chambers
which chamber is largeR?
lateral chamber
lateral chamber extends caudally into the
lacrimal bulla
medial chamber of maxillary sinus of sheep and goat is conitnous with
palatine sinus
frontal sinus of pigs surrounds what
cranial cavity (dorsally, laterally, caudally)
brain lies _____ below the skin protected by the two plates of bone
5 cm
pigs cannot be reliably stunned
humane slaughter requires use of electrocution or CO2
Shooting at intersection of diagonal lines connecting eyes with bases of opposite ears; or through occipital bone from behind
