Exam 2 Head Flashcards
What nerves provide moor innervation to muscles of lips and nose in the horse?
dorsal and ventral buccal branches of facial nerve
what considerations for the buccal branches do you have to make during anesthesia?
in lateral recumbancy, the buccal branches must be protected from the halter and hard surfaces; damage can result in facial paralysis
what are other branches of the facial nerves
transverse facial and auriculopalpebral
facial motor provides innervation to what in ox
muscles of lips and nose
what run under the ventral border of the mandible in the ox
facial artery, ,facial vein, parotid duct and ventral buccal branch
what runs along the ventral border of the mandible in small ruminants
facial vein (no facial artery in SR)
What artery supplies the face in small ruminants since it lacks a facial artery
transverse facial artery
where do parotid duct and ventral buccal branch run in small ruminants?
ventral border of the massetter
what structures run ventral to mandible in the horse
facial artery, facial vein, and parotid duct
location of cornual nerve in the ox
just ventral to the temporal line (with artery and vein)
cornual nerve supplies sensory innervation to
the horn
where is the cornual nerve blocked in the ox and small ruminant?
midway between the lateral canthus of the eye and base of the horn; just ventral to the temporal line
what nerves supply sensory innervation to the horn in the caprine?
cornual nerve and cornual branch of infratrochlear nerve
where is the cornual nerve blocked?
blocked midway between the medial canthus of the eye and base of the horn
equine nostril lateral side is composed of
skin, muscle, CCT
medial side of equine nostril is composed of
cartilaginous base
medial cartilage is composed of several cartilages including
lamina of alar cartilage and cornu of alar cartilage
lamina of alar cartilage location
dorsal
cornu of alar cartilage location
ventral
what is the alar fold in the equine?
mucous membrane fold continuous rostrally with skin covering lamina of alar cartilage and caudally with ventral nasal concha
what is the nasal diverticulum of the equine
blind pocket dorsal to alar fold
where is the nasolacrimal dct orifice located?
on floor of nasal vestibule
ox nose and nosrils are covered by
planum nasolabiale; highly keratinized region between nostrils and extending to the upper lip
small ruminants nose and nostrils are covered by
planum nasale
what is the philtrum
the grove separating right and left superior labii
what are the parts of the nasal septum
membranous part
cartilaginous part
osseous part
equine dorsal nasal concha
from cribiform plate to first cheek tooth
straight fold
extends from dorsalnasal concha to nostril
ventral nasal concha is composed of what two parts
alar fold and basal fold
alar fold
runs from ventral nasal concha to lamina of alar cartilage
basale fold
extends rostrally from ventral nasal concha
middle nasal/ethmoid concha
located caudodorsal nasal cavity
where are ethmoidal meatuses located
between ethmoturbinates
what is the location of nasomaxillary opening that communicates with the maxillary sinus?
middle nasal meatus
what is the location of the common nasal meatus
between nasal septum and conchae
where is the equine nasopharynx located
between nasal cavity and laryngopharynx
what is the rostral boundary of equine nasopharynx
choana
what is the caudal boundary of the eqine nasopharynx formed by
palatopharyngeal arch and free border of soft palate (intrapharyngeal ostium)
where is the pharyngeal opening of auditory tube
in equine nasopharynx
what is the pharyngeal septum in ruminants
prolongs nasal septum to dorsal wall of nasopharynx
where is the pharyngeal tonsil located in the ruminant
caudal end of pharyngeal septum
ruminants have tonsils where?
in oropharynx and nasopharynx
the auditory tube connects what?
the middle ear cavity to nasopharynx to equalize air pressure on each side of the eardrum
what is the guttural pouch?
the ventral diverticulum of the auditory tube (mucosa that extends ventrally)
auditory tube connects the guttural pouch to the
nasopharynx
auditory tube is supported by
bone caudally and by an incomplete cartilaginous tube rostrally.
guttural pouch is “draped” over the ______ forming ______
stylohyoid bone; medial and lateral compartments
which compartment is larger and more caudal
medial
pharyngeal opening of the auditory tube is open during what
expiration and swallowing
what is the plica salpingopharyngea
the mucosal fold attached to the lateral wall of pharynx and medial wall of auditory tube; located ventrally
ventrally, the medial compartment of the guttural pouch contacts the _______
medial retropharyngeal lns.
medial compartment of the guttural pouch also contacts (more likely to be damaged with guttural pouch pathology)
internal carotid artery glossopharyngeal n. vagus n. accessory n. hypoglossal n. cranial cervical ganglion sympathetic trunk
the lateral compartment of the guttural pouch has the _____ running along its lateral surface
facial nerve
what are the less common structures involved in guttural pouch pathology
facial n.
hypoglossal n
external carotid a.
what are the surgical approaches to the guttural pouch
hyovertebrotomy incision
viborg’s triangle
modified whitehouse incision
whitehouse incision
what are the surgical landmarks for the viborgs triangle?
linguofacial vein (ventral)
sternocephalicus (caudal)
caudle border of mandible (rostral)
functions of guttural pouch?
x
parotid lymph nodes of the horse drain to
lateral and media retropharyngeal lns.
mandibular lns of the horse drain to
cranial deep cervical lns, or medial retropharyngeal lns.
lateral retropharyngeal lns. location in horse
ventral to wing of atlas near caudodorsal border of mandibular salivary gland
lateral retropharyngeal lns contact
lateral wall of guttural pouch
lateral retropharyngeal lns in equine drain to
medial retropharyngeal lns. ventral to guttural pouch
medial retropharyngeal lns. in equine drain to
cranial deep cervical lns.
parotid lns of ruminants drain to
lateral retropharyngeal ln.
mandibular lymph nodes of ruminants drain to
lateral retropharyngeal ln
medial retropharyngeal lns of ruminant drain to
lateral retropharyngeal ln.
what is the major lymph collection center for the head in ruminants
lateral retropharyngeal ln.
lateral retropharyngeal ln. drain to
cranial deep cervical ln.
what is the function of the hyoid apparatus
the root of the tongue, pharynx, and larynx
learn parts of the cartilages
x
where is the aryepiglottic fold
from lateral edge of epiglotic cartilage to the corniculate process of the arytenoid cartilgae
what are the mucous membranes of the larynx of the horse
vocal fold
vestibular fold
laryngeal ventricle
vocal fold
covers vocal ligament and covalis m.
vestibular fold
covers vestibular ligamenta nd part of the ventricularis m.
laryngeal venricle
located between vestibular and vocal folds
what are the mucous membranes of the larynx of the ruminant
only vocal fold is present (no vestibular fold or laryngeal ventricle)
aditus laryngis
entrace to larynx
laryngeal cavity vestibule
between aditus laryngis and glottic cleft (rima glottidis)
laryngeal cavity glottic cleft ventrolateral boundary
vocal folds
laryngeal glottic cleft dorsolateral boundary
vocal processes and medial surfaces of arytenoid cartilages
infraglotic cavity
from glottic cleft to trachea bounded by cricoid cartilage
glottis includes
vocal folds and arytenoid cartilages
cricoarytenoideus dorsalis m. function
enlarges glottic cleft by rotating the arytenoid cartilage so that the vocal process moves laterally (abduction);
aslo pulls muscular process dorsocaudally, rotating the arytenoid so that the vocal process and fold are pulled laterally; opens glottic cleft
cricoarytenoideus dorsalis attachments
arises from lamina and median ridge of the cricoid cartilage; muscular process of the arytenoid cartilage
cricoarytenoideus dorsalis m. is innervated by
caudal laryngeal n.
recurrent laryngeal nerves (terminal end is caudal laryngeal n.)
innervates all intrinsic laryngeal muscles except cricothyroideus m.; sensory to the mucous membrane of the caudal portion of the larynx
cranial laryngeal n. innervates
cricothyroideus m.; sensory to the mucous membrane of the cranial portion of the larynx
recurrent laryngeal nerves and cranial laryngeal nerves are branches of
vagus nerve
normal position of the epiglottis during breathing in the horse
the horse is an obligate nasal breather because the soft palate is tightly opposed to the base of epiglottis; no communication between oropharynx and nasopharynx
dorsal displacement of the soft palate in the horse
causes functional partial obstruction of nasopharynx space; limits performance (most often diagnosed when complaint of exercise intolerance)
epiglottic entrapment in the horse
loose aryepiglottic folds and subepiglottic mucosa displace dorsally above the epiglottis;
what are the complaints of epiglottic entrapment in the horse
exercise intolerance is the main complaint; less commonly coughing, nasal exudate
epiglottic entrapment prevalance in thoroughbreds
0.9%
eppiglotic entrapment can be induced by
epiglottic hypoplasia; aryepiglottic fold inflammation/swelling
chronic cases of epiglottic entrapemnt in the horse
thickened fibrous tissue; 45% have ulceration present
does the horse have binocular vision
no
equine eye
has a ramp retina; ciliary m. of eye poorly developed; horse changes head position to focus
iridic granules/corpus nigrum found in
hores and ruminants (ox, sheep and goats)
what nerves do you block for enucleation of eye
oculomotor, trochlear, and abducens
ophthalmic and maxillary nerve of trigeminal nerve
zygomatic branch of auriculopalpebral n. of facial nerve
enucleation is a common procedure in
bovine
peterson eye block for enucleation of the bovine eye
anesthetizes nerves exiting foramen orbitorotundum; insert needle into depression just caudal to the angle formed by frontal and temporal processes of zygomatic bone; advance needle rostrally off coronoid process of mandible
peterson eye block you also need to anesthetize
zygomatic branch of the auriculopalpebral n. of facial nerve
