Flashcards in Q&A Head Deck (376)
What is the groove in the upper lip and between the nostrils?
What is everything rostral to the eye?
Muzzle / "snout"
What structures surround the opening of the mouth?
What are the flews?
fleshy, hanging lateral part of the upper lip, especially pendulous in some breeds: bloodhound.
What is the stop?
Angle of the nose bridge between the eyes; it varies in degree from breed to breed.
What are the names for the 2 eyelids?
Upper or superior palpebra, lower or inferior palpebra
What is the highest point or summit of the head?
Describe the external ear canal.
Vertical part and then horizontal part to the ear drum.
What is the show term for the back part of the head or skull (i.e., the external occipital protuberance)?
What is the show term for the cranial portion of the neck?
What is the show term for the top line of the neck?
What does the occipital bone form?
Caudal cranial cavity and caudal skull
What forms the lateral face, part of the hard palate and holds the upper cheek teeth?
Maxillary bone or maxilla
What bone forms the rostral wall of the cranial cavity?
How does the spinal cord enter the cranial cavity?
Foramen magnum (occipital bone)
The facial part of the skull houses what 2 cavities?
nasal and oral
What are the 3 types of canine skulls?
Mesaticephalic (average), Dolicephalic (long face), and Brachycephalic (short face)
What suspends the larynx and tongue from the skull?
What unpaired hyoid bone is palpable and prominent in lateral radiographs?
What bony arch forms the lateral side of the bony orbit?
What is the name of the bony socket that holds the eye?
What hard structure is formed by the horizontal parts of the incisive, palatine, and maxillary bones?
What foramen is located on the maxillary part of the skull?
What is the rostral opening of the mandibular part of the skull?
WHat is the smooth bulbous enlargement on the ventral surface of the temporal bone housing the middle ear?
Tympanic bulla/ middle ear
What scrolls of bone fill the nasal cavity?
What is the large opening caudal to the zygomatic arch where the external ear attaches?
External acoustic meatus
What cavity contains the brain, its meninges, and blood vessels?
Cranial cavity/vault, neurocranium, calvarium
What is the median protuberance of the caudal skull?
External Occipital Protuberance
What extends rostrally from the external occipital protuberance?
External Sagittal Crest
Where do the right and left halves of the mandible meet?
The articular (condylar) process of the mandible articulates with the mandibular fossa of the temporal bone to form what joint?
What structure of the skull articulate with the 1st cervical vertebra?
List the 4 major salivary glands in the dog.
Parotid, mandibular, sublingual, zygomatic
What is the course of the parotid duct?
Crosses the masseter in groove, pierces cheek across from upper PM4 (carnassial tooth)
How are the sublingual and mandibular glands related?
They share a capsule
What separates the respiratory and digestive passages in the head?
Hard and Soft Palates
What are the large papillae with a mote around them on the caudal part of the tongue?
Name 4 substance found in teeth from the outside in.
Enamel (superficial on crown)
Cementum (superficial on root)
What is the hardest substance in the body?
Name the 4 types of permanent teeth and give their abbreviations.
Incisors (I), Canine (C), Premolars (PM), Molars (M)
The premolars and the molars make up the ___________ teeth
Name the 2 sets of teeth
Deciduous and Permanent
Name the 3 parts of low-crowned (brachydont) teeth of carnivores.
Crown, neck, and root
What are the shorthand representations of the number of teeth?
What forms the bulk of the tooth and surrounds the pulp cavity?
Where are the nerves found in the teeth?
What is the socket the teeth sit in?
What holds the teeth in the alveoli? What does it connect?
Periodontal membrane, connects cementum on root with alveolar wall.
Write the permanent dental formula of the dog.
2(I 3/3, C1/1, P 4/4, M2/3)= 42
Is the dental formula constant in dogs? Why?
No, brachycephalic breeds may be missing teeth.
What is the permanent dental formula for the cat?
2(I2/3, C1/1, P3/2, M1/1)= 30
What is a furcation?
Where 2 roots separate from the body or the tooth in multi-rooted teeth
What are the deciduous formulas for the dog and cat?
Dog: 2(Id 3/3, Cd1/1, Pmd 3/3) = 28
Cat: 2(Id 3/3, Cd1/1, Pmd3/2) = 26
What is the common passageway for the digestive and respiratory systems?
What openings connect the pharynx to the middle ear?
Pharyngeal openings of auditory tubes
What are the 3 divisions of the pharynx?
Oro-, Naso-, & Laryngopharynx
Name the 2 openings from the nasal cavity into the nasopharynx.
Caudal nares/ choanae
Where in the pharynx is the palatine tonsil located?
Lateral wall of the oropharynx
The palatine tonsil sits in a ______ and is covered on its ______ side by the __________ _____________.
Sinus, medial, tonsilar fold
What groove in the upper lip and middle of the nose separates the nostrils?
What divides the nasal cavity sagittally into equal halves?
(Median) Nasal Septum
What opens at the junction between the skin and mucous membrane, at base of alar fold just inside the nostril (nasal vestibule)>
What are the bony scrolls covered by nasal mucosa that fill each half of the nasal cavity?
What passages are formed by the nasal conchae and nasal septum?
What is the largest meatus located between the ventral nasal concha and the hard palate?
Ventral nasal meatus
What is the largest laryngeal cartilage that is opened dorsally?
What is the signet ring-shaped, laryngeal cartilage?
List 3 processes of the arytenoid cartilage in the dog.
Vocal, muscular, corniculate
What does the pull of the cricoarytenoideus dorsalis m.?
Recurrent laryngeal (specifically: caudal laryngeal nerve)
What is the narrowest part of the laryngeal cavity?
What is the anatomical term for the eyelids?
List the parts of the conjunctiva?
Palpebral and bulbar conjunctiva separated by the conjunctival fornix
What is the 3rd eyelid?
Fold covering a "T"-shaped cartilage in the medial commissure
What happens when eyeball is retracted?
3rd eyelid crosses the eye to protect it
What is the gland of the 3rd eyelid?
Accessory lacrimal gland surrounding the cartilage of the 3rd eyelid
What are the 3 tunics of the eyeball from outside to inside?
Fibrous, vascular, nervous tunics
What are the 2 compartments of the fibrous tunic?
Corneal and sclera (white)
What is the connection between the cornea and the sclera?
Corneascleral junction (limbus)
What are the 3 compartments of the uvea (vascular tunic)?
Iris, ciliary body, and choroid
How is the size of the pupil controlled?
Dilator and sphincter mm. of the iris
What is the specialized area of the choroid which relfects light back?
Tapetal area (tapetum lucidum)
What is the blind spot of the eye?
Optic disc (where the optic nerve fibers leave the eye
Where is the tapetum lucidum located?
Superiolateral to optic disc
Excluding the optic nerve, which nerve is sensory from the eyeball?
Opthalmic branch (trigeminal n. )
What are the 3 spaces of the eyeball and their locations?
Anterior chamber- between cornea and iris
Posterior Chamber- between iris and lens
Vitreous chamber - behind lens
What moves the eyeball?
Extrinsic muscles of the eyeball
What innervates teh lateral rectus m. and thus abducts the eye?
Abducens, Cranial Nerve 6
What is the formula for the innervation of the extrinsic eye m.?
What innervated the orbicularis oculi m.?
What are the portions of the ear, the organ of hearing and balance?
Outer, middle, and inner
What are names for the flap of skin and cartilage forming the visible external ear?
Pinna, auricle, or "ear"
What is the skin pocket on the distolateral edge of the external ear?
Cutaneous marginal sac
What makes up the pinna?
Auricular cartilage covered on both sides with skin.
What is the tragus?
Initial part of the lateral wall of the ear canal lying opposite the anthelix
What is the passageway from the pinna to the ear drum?
External acoustic (auditory) meatus or ear canal
What are the parts of the external acoustic (auditory) meatus/canal?
Vertical and horizontal parts
What houses the middle ear?
What is contained in the middle ear?
Auditory ossicles and air
What is the auditory tube?
Connects the middle ear and nasopharynx
What are the auditory ossicles?
3 ear bones across the middle ear
Where is the bony labyrinth divided?
Vestibule, cochlea, and semicircular canals
WHat is the cochlea of the inner ear?
Snail shell-like part, associated with hearing
What is the spiral organ of Corti?
Organ of hearing
WIth what is static equilibrium detected by the maculae of the utricle and saccule concerned?
"Body (head) position" relative to gravity
What are the semicircular canals?
3 bony canals arranged at approximately right angles to each other
What is the function of the semicircular canals?
Detecting angular (rotational) acceleration or deceleration of the head (dynamic equilibrium)
When does normal physiological nystagmus always occur automatically?
When semicircular canals stimulated (pinning).
Involuntary rhythmic movement of the eyes in either a rotary, vertical, or horizontal direction, slow component in one direction with a quick return.
Where is the lacrimal gland located?
Dorsolateral to eyeball
What are the tiny holes in the upper and lower eyelids near the medial canthi?
What does the auriculopalpebral nerve (branch of CrN7) innervate?
Eyelids and ear muscles
What is the 8th cranial nerve? WIth what does it deal?
vestibulocochlear nerve, hearing, and balance/motion
What is the easiest way to think about the glossopharyngeal nerve?
Lump with vagus (X)
What cranial nerve carries autonomic nerve fibers between the brain and the viscera of the thorax and abdomen?
What is the recurrent laryngeal nerve?
Branch of the vagus n., arises in the thorax and extends back to larynx to end in ca. laryngeal nerve.
What does the recurrent laryngeal nerve (CrN12) innervate?
Motor to tongue muscles
What 3 cranial nerves are completely sensory, bringing impulses of special senses to the brain? What are those sense?
Olfactory (1): smell
Optic (2): sight
Vestibulocochlear (8): hearing/balance
Parasympathetic fibers are carried over what four cranial nerves?
What do ANS fibers to the head innervate?
Smooth muscle and glands of head (no heart muscle present).
How do sympathetic and parasympathetic fibers reach the head?
Para: over a few cranial nerves Sympathetic : from cranial cervical ganglion through middle ear and over cranial nerves.
What are the most clinically important ANS fibers in the head?
CrN7 to lacrimal gland and sympathetic to eye (Horner's syndrome)
Outline the pathway of the sympathetic innervation to the head
Nerves from the hypothalamus (UMN) down the cervical cord to the lateral (intermediolateral) gray column of the thoracic segments 1-4, preganglionic axons over the communicating branches and up the sympathetic trunk to the cranial cervical ganglion; postganglionic axons pass through the middle ear, cranial cavity and orbit over cranial nerves.
Through what head structures do sympathetic fibers to the eye pass?
Middle ear and orbit
What is the primary blood supply to the head?
Common carotid arteries
What artery winds around the ventral border of the mandible to reach and supply the face?
What is the vein on the ventral surface of the tongue?
What are the channels for venous blood between the 2 layers of the dura mater?
Where are the major lymph nodes of the head located?
Parotid: rostral to parotid gland
Mandibular: angle of the jaw
Med. Retropharyngeal: dorsal to pharynx
What lymph nodes of the head are palpable?
Lat. Retropharyngeal- if present
Med. Retropharyngeal- Not Palpable
How is the brain divided functionally?
Which parts of the brain are mainly concerned with movement?
Which with posture?
Which with coordinating movement?
Cerebrum, basal nuclei (ganglia),
How are motor neurons divided by location?
Upper motor neurons (UMN), Lower Motor Neurons (LMN)
What is the proprioceptive pathway?
Peripheral n., spinal cord, brain stem, cerebrum, or cerebellum
What body muscles does each cerebral hemisphere control?
What does the contralateral and ipsilateral mean?
Contralateral: opposite side
Ipsilateral: same side
How does the hypothalmus regulate the viscera?
controlling and integrating the autonomic nervous system (ANS)
What is the function of the thalamus?
Central relay and integrative center for sensory impulses to the cerebral cortex
What is responsible for consciousness and arousal?
Reticular activation system (RAS)
List three clinically significant parts of the brainstem.
Cranial nerves 3-12, gait centers and reticular activation system
Where are the walking/gait centers located?
In brainstem caudal to the midbrain
Where do descending motor tracts (UMN) from higher centers (cerebrum) that initiate motion cross over?
What is the function of the cerebellum?
Coordinate movements (not initiate), maintain equilibrium and maintain posture
What information does the cerebellum evaluate to carry out its functions?
Proprioception (sensing body position)
What is the function of the vestibular system?
Maintain posture with respect to gravity and coordinating eye and head movements.
Where is the vestibular system located?
In inner ear (peripheral part) and brain stem (central part)
What are the interconnected cavities of the brain containing CSF?
What substances don't pass the blood brain barrier?
Large proteins and most antibiotics
How do cat skulls differ form the dog?
Greater doming of the frontal and nasal bones, smaller frontal sinuses (may be absent in Persians), more complete bony orbits and wider skulls (zygomatic arches)
For what are DV skull projection viewed?
View for symmetry by comparing one side to the other
What are the delicate multiple longitudinal lines seen in the nasal cavity of skull radiographs?
Conchal detail (bony scrolls of ethmoid and ventral nasal conchae)
Why can soft plate (soft tissue density) seen radiographically in a lateral skull radiograph where it is overlapped by bone densities?
Soft tissue density contrasted by the air in the pharynx
How is the nasal cavity evaluated in the DV/VD and the open mouth VD views?
Compare the right and left half for opacity or lucency
What should be done if there is a radiographic difference in the density of one half of the nasal cavity (heminasum) compared with the other?
Look for the fine detail (nasal conchae)
What does conchal detail tell you if there is heminasum (density difference between halves of nasal cavity)?
a) If present on both sides:
b)Missing from one side:
A)Densest side is diseased (exidate, blood, tumor)
B)Diseased side regardless of whether it is dense (exudate, blood, tumor) or lucent (usually fungal rhinitis)
What is the #1 clinical radiographic finding of the hyoid bones?
What radiographic view separates the teeth of the opposite jaws?
Open mouth, lateral oblique projections
What is the lamina dura seen in head radiographs?
Side of the tooth socket (alveolus)
What is the purpose of an open mouth ventrodorsal (VD) view?
Unobstructed view of the nasal cavity, frontal sinuses, and/or upper dental arcade
What projection isolates the upper or lower jaw, respectively, from the other jaw?
DV and VD occlusal (intraoral) projections
How do you differentiated an DV and VD occlusal (intraoral) projections from a VD/DV or open mouthed VD views?
Caudal skull or mandible is cut off by the edge of the film obliquely
What radiographic projection separates the TM joints, tympanic bullae, or frontal sinuses so they are not superimposed?
Lateral oblique TMJ, lateral oblique tympanic bullae, or lateral oblique frontal sinus view.
How is the rostrocaudal frontal and foramen magnum views recognized?
R.Ca. frontal: frontal sinus highlighted
Rcr foramen magnum: cranial vault and foramen magnum highlighted
What view highlights the tympanic bullae and dens (odontoid process) of the axis?
Open-mouth rostrocaudal (RCa) view
What does erosion or missing lamina dura indicates in a radiograph?
A problem with the tooth
What is the most common dental disease causing resorption of the lamina dura?
What radiographic view shows enlargement of the foramen magnum?
Open-mouth rostrocaudal view
When is surgery performed for skull fractures?
Depression fractures of the frontal sinus and into the brain
What surgical procedure can be used to treat middle ear infections?
Open tympanic bulla via mouth for drainage
What must be done for fractures of maxilla and mandible?
Restore normal anatomical alignment (dental occlusion)
How are mandibular symphyseal fractures treated?
Cerclage wire stabilization (hypodermic needle guide for wire through the skin).
What is the term for encircling of a part with a wire?
What is a cleft palate, hare lip?
Defect in the hard and soft palate and lip
What bone may be broken in small dogs due to choke chains
Fracture of the hyoid apparatus (usu. epihyoid bone)
How is TMJ/mandibular luxation treated?
Replace mandible via closed reduction: anesthetized in dorsal recumbency, pencil or dowel across last molars, close mouth over pencil and move jaw back in place
Why are lymph nodes cut and checked during meat (cow not dog!) inspection and necropsy?
Checked for changes in color and consistency indicting pathogenic processes
How are the dog's mandibular lymph nodes and salivary gland palpated?
Grasp skin and deep structures at jaw angle. Let them slip through fingers and feel a big lump (mandibular gland) and a few small lumps (lymph nodes)
What is an accumulation of saliva causing a swelling called?
Salivary mucocele, sialocele, or ranula (under tongue)
How can keratoconjunctivitis sicca (dry eye) be treated surgically?
Transposition of parotid duct to fornix of the conjunctiva
At what level do the parotid and zygomatic ducts open into the buccal vestibule?
P: upper carnassial
Z: last upper molar
What is a ranula?
Mucocele under the tongue due to rupture of the sublingual (#1) or mandibular duct
What is also removed if the monostomatic sublingual gland is removed? Why?
Mandibular gland, same capsule
Protrusion of the eye (exophthalmos) due to inflammation of the zygomatic salivary gland must be differentiated from what?
Abscess; abscess more common
The mandibular lymph nodes can be palpated in a _____ ______ _____ lateral to the immovable mandibular salivary gland.
fold of skin
What is inflammation of the mouth, gums, and tongue?
Stomatitis, gingivitis, and glossitis
What is a defect in hard palate?
What is chronic lip fold dermatitis?
Long term moist dermatitis in breeds with pendulous lips (ex. St. Bernards)
How much of the dogs tongue can be amputated without problems?
Up to 1/3rd of tongue missing ok
What is an elongated jaw (mandible)?
"Overshot" (prognathia), sow mouth, monkey mouth [mesioclusion-underbite?]
What is a shortened jaw (mandible)?
"Undershot" (brachygnathia), parrot mouth, distoclusion- overbite
What results in swelling or draining (pus) below the carnivore's eye?
Carnassial tooth abscess (upper P4)
How is the carnassial tooth (upper P4) removed?
Split first because has 3 roots - dogs and cats
Why should upper P4 be split before it is removed?
3 roots diverge, a root or jaw may break if not split
How is aging of dog by their teeth used practically in dogs?
Baby teeth in by 6 weeks - vaccination,
Adult in by 6 months - time to spay
How are cats aged by their teeth?
Like dogs, baby by 6 weeks, adult by 6 months
Which dog teeth have 3 roots?
Last 3 on top
Which cat permanent tooth has 3 roots?
Upper P4 (carnassial)
In the dog, how many teeth should there be between the canines and the carnassial teeth in the upper and lower jaw?
Upper: 3 between C and P4
Lower: 4 between C and M1
How are teeth fractures divided into 2 groups?
Complicated and uncomplicated, depending on if pulp exposed or not, respectively
What can you say about a discolored tooth?
What can cause discoloration of enamel of puppy teeth?
High temperature when developing )ex: distemper) or tetracycline antibiotics ised.
What is the #1 disease of teeth in dogs?
What 2 teeth most commonly have plaque build up?
#1 carnassial teeth, then canines
What is the #1 canines of pulpitis/endodontic disease?
Tooth fractures with pulp exposure
What is polydontia?
Supernumeracy teeth: too many teeth
How should supernumeracy teeth be treated?
If crowd other teeth, remove
What are deciduous teeth present along with their permanent counterpart?
Retained deciduous teeth
What is a malocclusion?
Malposition of teeth resulting in the faulty meeting of the teeth or jaws
What point is used to measure the recession of the gums?
What is the clinical significance of furcations?
Common site for attachment loss and periodontal disease
What should be done if a furcation is exposed (attachment loss)?
Degree of exposure should be measured and recorded
A staphylectomy/uvulectomy is the removal of the ______________, to reduce respiratory distress in some brachycephalic dogs.
Caudal free edge of the soft palate
Where may bones become lodged and shut off the laryngeal opening of the airway in the dog?
Describe how a pharyngostomy tube is placed in a dog?
Press the pyriform recess laterally with a hemostat and incise, grasp the tube and pull it through the incision and out the mouth. Reverse the tube down the esophagus into the stomach and suture it to the neck.
What and when is a tonsillectomy performed?
Removal of tonsils rarely done in carnivores, but it provides permanent relief
Dysphagia is a clinical sign not a disease, what should always be R/O (rule out) first if dysphagia is present?
Rabies in all dysphagia
Where are common locations of esophageal foreign bodies?
Where passage is constricted: thoracic inlet, over base of heart, in front of diaphragm
How are esophageal foreign bodies removed?
Cervical: esophascope and alligator forceps, if fails, do a gastrotomy and pull the object into the stomach
Are esophageal surgeries simples procedures with few complications?
No, avoided if possible
The esophagus is accessible to surgery in the ______ half of the neck region on the ________ side.
How are stenotic nares treated surgically?
Wedge restriction: surgically increasing the nasal openings
Where must a nasogastric tube be passed?
Through the ventral nasal meatus
What is inflammation of the nasal cavity?
What is difficult breathing?
What is epistaxis?
Bleeding from the nose
What is the term for bleeding from the nose?
What is the term for difficult breathing?
What is trephination?
Removing a circular disk of bone with a crown saw, chiefly from the skull
What is a rhinotomy with a bone flap?
Opening nasal cavity by cutting a flap of bone
List 3 anatomical characterisitcs of the brachycephalic syndrome?
1. Stenotic nares
2. Elongated soft palate
3. Everted laryngeal saccules
What is surgically amputating the saccule/laryngeal ventricle?
A laryngotomy to open larynx goes through what paired muscle to expose the larynx?
Sternohyoid muscles, middle "strap muscle"
What surgical landmark indicates the ventral midline of the larynx?
Cricothyroideus or bow tie muscle
How is laryngotomy performed?
Through paired sternohyoid muscles, (middle "strap muscles"), then cricothyroid ligament
Paralysis of what muscle results in laryngeal paralysis in dogs and "roarers" (laryngeal hemiplegia) in horses?
Cricoarytenoideus dorsalis muscle
What is done after the endotracheal tube is placed into trachea?
Inflate endotracheal tube cuff and tie tube around upper jaw with gauze (so not swallowed or spit out)
Describe laryngeal collapse.
Processes of the arytenoid cartilage (corniculate and cuneiform) overlap, causing collapse
Describe laryngeal spasm.
Shutting of a cat's larynx when intubation attempted
What is the injection and aspiration of material into and from the trachea for lab work?
Transtracheal wash (TTW)
Where is a good place for a tracheotomy/tracheostomy and why?
Cranial neck, trachea covered only by strap muscles
What tracheal disease causes respiratory distress in obese small dogs?
Collapse of the trachea
What is inflammation of the conjunctiva?
Conjunctivitis, red eye
Where may foreign bodies lodge in the adnexa of the eye?
Conjunctival fornix or sac, or behind the 3rd eyelid
What is a misplaced eyelash that rubs against the cornea?
What is the inversion and eversion of the margins of the eyelids? Which is worse clinically?
Entropion (inward rolling)
Ectropion (outward rolling)
What is the term for tonic blinking/spasmodic winking?
What does a weak to absent palpebral reflex indicate during surgery?
What does a weak to absent palpebral reflex indicate during surgery?
What is the purpose of a conjunctival flap surgery?
Protect and help heal corneal ulcer
What is hypertrophy and prolapse of the superficial gland of the 3rd eyelid?
Cherry eye or Haws
What is a 3rd eyelid flap or temporary tarsorrhaphy?
3rd eyelid pulled over cornea and sutured
What is the overflow of the eyelids by tears?
What is treatment for "weeping dog syndrome", dacryocystitis, nasolacrimal obstruction?
Flushing by cannulating the lacrimal puncta or nasolacrimal duct
What is a cosmetic sequele to epiphora?
What is the term for dry eye?
KCS, keratoconjunctivitis sicca
How does facial nerve paralysis affect the eye?
Lacrimal gland and orbicularis oculi muscle (can't close eye) causes dry eye
What are treatments for keratoconjunctivitis sicca?
Artificial tears or transposition of the parotid duct are treatments
How is the amount of tear flow checked?
Schirmer's tear test
What is the term for recession of eyeball into orbit?
What is abnormal protrusion of the eye?
What is an accumulation of pus behind the globe in the orbit?
What is the approach to drain a retrobulbar abscess?
Incision behind last upper molar
What is proptosis?
Prolapse of the globe rostrally
What is inflammation of the cornea?
What is the first thing to think when you see a corneal ucler?
No steroid as slows healing, predisposes to perforation
How do you check for corneal ulcers?
Fluorescein dye retention = hallmark of corneal ulceration - bright green
What is a descemetocele?
Herniation of Decimate's membrane, usually through a corneal wound or deep ulceration
What is inflammation of the iris and ciliary body?
Anterior uveitis, iritis, iridocyclitis
What is the condition in which the pupils are of different size?
What is the term for a dilated pupil?
Mydriasis (aka pupil)
What is the separation of the neural retina from the retinal pigmented epithelium?
What is the spectrum of posterior malformation of the eye seen in 80% of purebred collies?
What condition is caused by increased intraocular pressure (IOP)?
What is any opacity in the lens?
What is required to do an extraction of a cataract?
A functional retina
How are auricular/aural hematoma treated?
Drain, suturing ear to close dead space and maintain pressure while healing
Describe how an otoscopic exam is performed?
Otoscope vertically into the vertical part of the ear canal, at bottom turn the otoscope medially and advance it into the horizontal part to see the ear drum
What is inflammation of the external ear canal?
Describe a Zepp operation/lateral ear resection?
Cut lateral wall of the vertical canal and sutured down to make a "drain board"
How can you equalize pressure differences on either side of the tympanic membrane during an airplane flight?
Open pharyngeal opening of the auditory tube allows air into the middle ear (chewing gum and yawning)
What nerve problems can otitis media cause?
Dry eye, facial palsy &/or Horner's syndrome
What can sequele to otitis interna related to balance?
What pets are predisposed to deafness?
White cats with blue irises and more that 20 breeds of dogs
Where can CSF be obtained from an animal?
Cisterna magna (cerebellomedullary cistern) and lumbar subarachnoid space (lumbar cistern)
Describe the procedure of a CSF tap done in the cisterna magna
Insert needle where cranial wing of atlas cross line between external occipital protuberance and spine of the axis. "Pop" through atlanto-occipital membrane into cisternal magna. Remove stylet to see CSF (collect CSF); if not, replace stylet, advance and repeat
What is critical when placing the spinal needle for a cisterna magna tap?
Critical to stay on midline
What are clinical signs of meningitis?
Cervical rigidity (due to pain [hyperesthesia]), fever and lameness
What is meningitis associated with inflammation of the underlying brain?
What vessel in carnivores is an alternative site for venipuncture, the 2nd choice after the cephalic vein?
External jugular vein
What is a possible site for venipuncture during surgery if other vessels are inaccessible?
Lingual vein: on ventral surface of the tongue
What is a problem of using the lingual vein for venipuncture? Why?
Hematoma because of loose tissue surrounding it
What large vein must be avoided when doing orbital surgery?
Angularis oculi vein: near medial canthus
How can the transverse facial artery be clinically used in horses?
To take a pulse
How can infection spread from the face to the cranial cavity?
Connections between facial veins and the cranial venous sinuses
Why can infection or neoplasia spread to the vertebral column instead of the expected lungs?
Valve less ventral internal vertebral venous plexuses that allows blood to pass in either direction
Why are mental attitude/consciousness, behavior, seizures, stance and head position, gait and weakness and proprioceptive positioning observed?
To screen for neurological problems
What evaluates the entire nervous system?
Gait and strength observation, proprioception
What do gait abnormalities indicate?
Nervous system problem (cerebrum, cerebellum, brain stem, spinal cord, peripheral nerves, or vestibular lesions)
What screening test indicates a nervous problem somewhere other than the cerebellum (or peripheral vestibular system)?
What is the only part of the nervous system that will not result in weakness?
Cerebellum (& peripheral vestibular system)
How is proprioceptive positioning (knuckling) used for?
Sensitive screen for neurological problems not localization
Where does loss of proprioception tell you clinically?
Sensitive indication of a neurological problem somewhere in peripheral n., spinal cord, brain stem, cerebrum, or cerebellum
What is done once screening indicates a neurological problem?
Other procedures done to localize the lesion to a specific part of the nervous system: head, spinal cord, periphery, neuromuscular junction, or muscles
What signs would rule in a disorder above the foramen magnum?
What signs would R/O (rule out) a disorder above the foramen magnum?
NO "head signs" (normal mental attitude, consciousness, head position, cranial nerves)
What spinal reflexes are tested to evaluate the spinal cord?
Flexor reflex (rear limb)
Withdrawal reflex (all limbs)
List 5 head signs of a neurology problem above the foramen magnum.
Changes in mental attitude, mentation, consciousness and behavior, seizures; head tilt; head tremors; circling; cranial nerves deficits
Where is the lesion of an animal with head signs depending on its gait and strength?
a. Head sings + normal gait
b. Head signs + gait deficits, paresis/paralysis (4 or 2 ipsilateral limbs)
c. Head signs + gait deficits (incoordination or dysmetria), no weakness
d. Head Signs + leaning, circling, no weakness
e. Head Signs + leaning, circling, weakness
a. Rostral to midbrain (cerebrum or diencephalon)
b. Brain stem
d. Peripheral vestibular
e. Central vestibular
Where does gait deficits without head signs localize the lesion?
To the spinal cord, peripheral nerves, neuromuscular junction, or diffuse muscular lesion
How is an animal with normal mental state described?
BAR (bright, alert, and responsive)
List 3 primary deficits that may be seen with lesions to the forebrain (cerebrum/diencephalon)?
Seizures, Alteration of behavior and mentation, consciousness, abnormal posture (proprioception) with normal gait, blind with normal pupillary reflexes, compulsive pacing, head pressing
What are signs of hypothalamic dysfunction?
Polyuria, polydipsia, hyperphagia, poor temperature regulation, altered sleep patterns
How is brain stem disease characterized?
Abnormal gait + abnormal posture, Cranial nerve deficits, decreased consciousness, weakness (paresis)/paralysis
What is the range of decreased levels of consciousness due to brainstem lesions?
Depression, stupor to coma
What is the best evidence of brainstem lesions?
Dysfunction of cranial nerves
How does a cerebellar lesion present?
Uncoordinated without paresis (no weakness)
To what are all signs of cerebellar disease related?
Alteration in coordination
What characterizes cerebellar ataxia?
Wide based stance, dysmetria, and intention tremors
How do kittens with cerebellar hypoplasia present?
Incoordination, intention tremors and dysmetria
What is occipital dysplasia?
Congenital enlargement of the foramen magnum in toy breeds (poms and yorkies)
List (short) the common signs of both central and peripheral vestibular disease.
Head tilt, circling towards lesion, nystagmus, ataxia, strabismus, vomitting
How is the vestibular system tested?
Observe gait, nystagmus, alter body position, positional nystagmus, righting reflexes
What is the primary diagnostic concern with vestibular disease?
Differentiating peripheral from central vestibular disease
What is nystagmus?
Involuntary rhythmic of both eyeballs in unison (slow and quick components)
What are the most common causes of nystagmus?
Cerebellar or vestibular apparatus lesions
Describe the slow phase of vestibular nystagmus
Slow phase toward the lesion
How does central and peripheral vestibular disease present?
Central: vestibular signs + weakness and postural deficits + common vestibular signs
How is peripheral vestibular different from central vestibular disease?
No weakness or postural deficits
Why is central vestibular disease different from peripheral disease?
Central: has brain stem signs (paresis and postural deficits)
Uncoordinated gait (staggering and irregular muscular movements, tendency to cross limbs, exaggerated or hypermetric movements)
List three types of ataxia?
Propprioceptive ataxia (spinal cord, brain stem, cerebrum); cerebellar, and vestibular ataxia
How are the types of ataxia localized?
Asymmetry: yes in vestibular, no in others usually; Postural reactions: abnormal: proprioceptive ataxia and central vestibular, not cerebellar
Describe the pathophysiology of the neurological aspect of tentorial herniation?
Squeezing the cerebrum into cerebellar compartment past the tentorial partition between cerebrum and cerebellum due to increasing intracranial pressure (edema, bleeding)
What is a common cause of slow, insidious progressive neurological signs?
Define myoclonus ("corea")
Rhythmic twitching of muscles, pathognomonic for distemper
Which nerves deal with eye movement? How are they tested?
III, IV, VI: CrN 3, 4, 6; visualizing eye position
What results from dysfunction of the optic nerve (CrN 2)?
How is the optic nerve tested?
Menace response and pupillary light reflex
Describe the pupillary light reflex
Shining a light in the eyes, not the pupil constricting in that eye (direct response) and the other eye (indirect response)
What does the pupillary light reflex check?
Both the optic (sensory) and oculomotor (motor) nerves
What is the menace response?
Blinking in response to potentially harmful objects advancing toward the eye = sight
Describe performing a menace response.
Make a threatening gesture toward the eye without windpuffs or noise (throw a cotton ball).
How is a menace response checked?
Threaten eye with hand or cotton ball.
What cranial nerves are checked by observing eye position, movements and pupil size?
Cranial nerves - 4, 6, 3 sympathetic
What cranial nerves are checked with pupillary light reflexes test?
CrN 2 and 3 (optic and oculomotor)
What clinical signs may develop from injury to trigeminal nerve?
Sensory deficit of face and drooped jaw
What nerves of the face can be palpated and blocked where?
Infraorbital and mental nerves emerging from the infraorbital and mental foramina
Why is paralysis of the orbicularis oculi and loss of lacrimation the most vital results of facial nerve paralysis?
Drying of eye, animals not vain (facial paralysis), glossopharyngeal nerve also has taste fibers
Why isn't the auriculopalpebral nerve blocked in small animals?
General anesthesia easier and more convenient
Describe a palpebral reflex when there is a proper level of anesthesia for most procedures.
Weak to absent palpebral reflex.
What cranial nerves are associated with the following complaints?
9a. Anisocoria (unequal sized pupil)
9b. Strabismus (uncontrolled deviation of eye)
9c. Dropped jaw and head atrophy
9d. Increase or decrease facial sensation
9e. Facial paralysis
9f. Dysphagia (difficult swallowing)
9h. Laryngeal Paralysis
9i. Paralysis of tongue
9a. Sympathetic, parasympathetic (3).
9b. Oculomotor(3), Trochlear(4), Abducent (6)
9c. Trigeminal (5)
9d. Trigeminal (5)
9e. Facial (7)
9f.Glossopharyngeal (9), Vagus (10)
9g. Vagus (10)
9h. Vagus (10): recurrent laryngeal
9i. Hypoglossal (12)
How is the facial/trigeminal reflex arc checked?
Prick face, pulling away indicates intact trigeminal nerve, twitch of face muscles indicated intact facial nerve
List three clinical signs of cranial nerve dysfunction that you should rule out rabies first.
List three clinical signs of cranial nerve dysfunction that you should rule out rabies first.
What is tested by putting your finger down a dog's throat?
Gag reflex- CrN 10, 9 (vagus, glossopharyngeal)
List the cardinal signs of Horner's syndrome
Miosis, enophthalmos, ptosis (drooping eyelid), protrusion of 3rd eyelid.
What is required to diagnose Horner's syndrome?
Presence of at least 3 or 4 cardinal signs
List the pathway along which a lesion can cause Horner's syndrome.
Spinal Cord (hypothalmus) to brachial plexus, up neck (vagosympathetic trunk) through middle ear and orbit
What is miosis?
Constriction of pupil; small word- small pupil
What is anisocoria?
Unequal sized pupils
What is a sac of deprivation of blood results in permanent damage to brain cells?
What is a thrombus?
A fibrin clot of a blood vessel of heart chamber
What is an embolus?
Clot, air bubble, or debri transported in the bloodstream. It may block a smaller vessel
What is a thromboembolus?
Thrombotic material transported in the bloodstream as an embolus to another site usually pluggin a vessel
What is the most important component of the blood brain barrier?
Nonfenstrated capillaries (continuity of endothelial cells)
What is hydrocephalus?
Pathological accumulation of CSF in ventricular sustem or subarachnoid space/
What is external (communicating) hydrocephalus?
Interference with drainage of CSF into dural sinuses
What is an accumulation of cerebrospinal fluid in the ventricles of the brain?
Internal (noncommunicating) hydrocephalus
What does internal noncommunicating hydrocephalus cause?
Where is the highest incidence of blockage of the ventricular system?
Mesencephalic (cerebral) aqueduct
What clinical problem involving the third eyelid particularly in field and hunting dogs?
Grass seeds or foxtails can become trapped behind the third eyelid
How can grass seeds or foxtails that have become trapped behind the third eyelid be seen?
Anaesthetize the eye topically, grasp the 3rd eyelid, pull it out and look between it and the eye
What head vessel may be a convenient place to give an injection in the dog unexpectedly waking up from anesthesia?
To what can eye and coat color (blue eyed/white coat) can be related to clinically?
Describe how capillary refill time (CRT) is taken
Press firmly on the gums for a second, count the time it takes for the color to return
What is a normal capillary refill time (CRT)?
1-2 seconds, any longer indicates a problem
Give to clinical problems of the external ear canal.
Otitis externa and ear mites