Skull Flashcards
Joint where the skull joins the spine?
Atlantocippital
Dogs have 3 types of skulls, cats have 1. What are the 3 types and what determines the catagories?
Doliocephalic, Mesaticephalic, Brachycephalic
Nasal cavity vs. cranium length (14 bones, 4 paired, 6 unpaired)
frontal, parietal, occipital, temporal, sphenoid, basioccipital, and cribiform plate of the ethmoid bone
Bones of the skull, lateral , dorsal, ventral?
Normal cat skull (lateral)
dorsoventral
The temporomandibular joint is a _____ jt. which articulates b/t the condylar process of the mandible and the mandibular fossa of the ____ bone.
synovial
temporal
TMJ is bounded caudally by the _______ process of the temporal bone and rostrodorsally by articular eminence ( a raised area located on the articulated surface of the temporal bone, in conjunction with the condyle of the mandible it allows for the opening and closing)
Cats have a tighter TMJ than dogs due to their large _______ process.
retroarticular ( a prominence or projection, as from a bone.)
retroarticular
Mandibular symphysis is a cartilage joint that permits the mandibular rami to move independently and allows the TMJ to _____ w/o fracturing.
luxate
Skull measurements.
A. Dorsal view:
- Skull length, 2. Facial length, 3. Upper neurocranium length, 4. Cranial length, 5. Viscerocranial length, 6. Greatest length of the nasals, 7. Snout length, 8. Least breadth between the orbits, 9. Frontal breadth, 10. Least breadth of skull, 11. Maximum width of neurocranium, 12. Maximum zygomatic width, Ak. Akrokranion, E. Euryon, Ect. Ectorbitale, Ent. Entorbitale, N. Nasion, P. Prosthion, Z. Zygion.
Skull measurements- ventral view
- Condylobasal length, 2. Basal length, 3. Median palatal length, 4. Length of the horizontal part of the palatine, 5. Length of the horizontal part of the palatine-1, 6. Palatal length, 7. Greatest breadth of the palatine (P4 level), 8. Least palatal breadth, 9. Breadth at the canine alveoli, 10. Length of the premolar row, 11. Length of the molar row, 12. Length of the cheektooth row, 13. Greatest diameter of the auditory bulla, 14. Breadth dorsal to the external auditory meatus, Ba. Basion, P. Prosthion, Po. Palatinoorale, St. Stayphylion.
Skull measurements continued.
A. Left-Lateral view:
- Greatest inner height of orbit, 2. Neurocranium length, 3. Braincase length, 4. Skull height, Ba. Basion, Cp. Cribriform plate, N. Nasion
Occipital view:
- Height of the occipital triangle, 2. Height of the foramen magnum, 3. Maximum width of the foramen magnum, 4. Maximum width of occipital condyles, 5. Greatest breadth of the bases of the jugular process, 6. Greatest mastoid breadth, Ba .Basion, O. Opisthion, Ot. Otion.
What is the name of this bone and what does it do?
cribiform plate- seperates the nasal cavity from the brain
The horse breathes through nares (nostrils) which expand during exercise. The nasal passages have two turbinates on either side which increase the surface area to which air is exposed. Name them.
1 : Concha nasalis dorsalis 2 : Concha nasalis media 3 : Concha nasalis ventralis
Maxillary turbinates are ____ and ethmoid turbinates are ____.
cranial
caudal
What is the difference between alveolar crest and the neck of the tooth?
Neck= area b/t crown and root of tooth
Alveolar crest= surface bone b/t teeth
Describe the difference b/t the larynx, nasopharynx, oropharynx and pharynx?
Pharynx- extends from level of orbit to C1-2 and is associated with both respiratory and digestive systmes
Nasopharynx is a space caudal to the hard palate and dorsal to the soft palate
oropharynx- is ventral to soft palate, b/t tongue, tonsils, and larynx.
Larynx- the hollow muscular organ forming an air passage to the lungs and holding the vocal cords in humans and other mammals; the voice box.
The _______ are those curly cue bones that do the rolly thing and the nasal septum is what’s grooving down the middle.
turbinates
What is the name of the tissue that would cover the turbinates?
conchae
The ______ is the “oral” pharynx, so that’s how you can remember it. And the _______ is the “nasal” pharynx that we use to breathe! And you can see the hard palate really easily in most dogs and cats, it’s just the roof of the mouth. The soft palate is that thing in pugs that makes them make the snorty noise.
oropharynx
nasopharynx
Then we got the larynx. The larynx is actually the assortment of the _____, _____ ____, and the _____.
epiglottis, arytenoid cartilage and vocal fold.
What bone?
Then we got the hyoid bone, which is easiest to be seen on an x-ray.
Name the hyoid bones.
SECBT
Styelohyoid
epihyoid
ceratohyoid
basihyoid
thyrohyoid
Look at rad
Retrophyangeal space…what is it?
Potential space b/t the pharynx and spine and normally is uniform ST opacity. Dorsoventral dimension of retropharyngeal space should not exceed length of C3 on a properly positioned lateral rad.
What is alveolar bone?
What else is compact bone known as? How many layers does it have?
What are it’s functions of the cortical bone layers?
What is the purpose of Spongy Bone?
Where is Craniomandibular osteopathy usually present itself?
Near the angular process. Extensive, irregular periosteal new bone production is present along the mandible (arrow)
What do you call it whena stiffness of a joint due to abnormal adhesion and rigidity of the bones of the joint, which may be the result of injury or disease. The rigidity may be complete or partial and may be due to inflammation of the tendinous or muscular structures outside the joint or of the tissues of the joint itself?
Ankylosis or anchylosis
How can you identify a crainal vault fracture?
CNS and neural issues from fracture displacement, subdural hemorrhage, extradural hemorrhage, brain contusion (a region of injured tissue or skin in which blood capillaries have been ruptured; a bruise.)
Sub cutaneous emphysema,
Where is the grey and white mater in the brain vs. the spinal cord?
How much prefrontal cortex does a human, dog, cat have and what does that mean
Brain= grey outer, white inner
SC= Grey inner, white outer
Human= 30%, Dog= 7%, Cat= 1% (can’t tell the difference b/t moral right and wrong)
What do you call an abnormal excessive accumulation of fluid in the ventricular system of the brain?
Hydrocehalus- diagnosis is generally straightforward and is based on signalment, clinical signs, physical exam findings, and confirmation of ventriculomegaly. It must be understood that enlargement of the ventricles and the presence of an open fontanelle are not necessarily of any clinical significance. The patient must demonstrate signs of a brain disorder in the absence of any concurrent, active causal disease that may be responsible (e.g. encephalitis, metabolic encephalopathy). In patients with a patent fontanelle, the diagnosis may be confirmed with ultrasonography. Advanced imaging (CT, MRI) is the preferred method for imaging and confirming the diagnosis and for ruling out any concurrent disorders. MRI (Figure 4) will reveal dilation in the ventricular system and loss of the adjacent parenchyma. Treatment is aimed at reducing CSF volume and production. Prednisone or carbonic anhydrase inhibitors have been used with variable success. Surgical intervention is the treatment of choice and is aimed to divert CSF away from the ventricular system to the peritoneal cavity, pleural space, or right atrium. Ventriculoperitoneal shunting is the most common, technically feasible procedure done in domestic animals and can be done even on very small patients, such a Chihuahua’s. Prognosis is highly variable and depends on the degree of pre-operative neurologic dysfunction, chronicity, and avoidance of complications (infection, occlusion) associated with the shunt. Success rates as high as 90% have been reported with ventriculoperitoneal shunts, but owners must be advised that long-term prognosis for full return to function is guarded.
What is a tumor consists of multiple small compact osteocartilaginous lobules usually arising in the canine skull?
multilobular tumor
A type of metastatic neoplasia that can affect the skull where it forms multicentric lytic lesions that have a characteristic radiographic appearance of a “punched-out” lesion without a sclerotic margin. What is it?
multiple myeloma
Crainial Vault Tumor (CVT)- Causes ill-defined periosteal response involve rostral aspect of frontal bone w/ adjacent ST swelling is what ?
Osteosarcoma of the skull
CVT- A smooth boardered-osteosclerotic thickening involves the frontal bone with little soft tissue sweeling is what?
Osteoma of the skull
CVT- What causes an invasive lobulated lytic lesion with diffuse amorphous calcification of the frontal and parietal regions?
Multilobular osteoma/chondromal of the skull
CVT- What causes a severe soft tissue swelling and maxillar yosteolysis (arrow) with ill-defined bony margins?
Soft tissue infiltrating maxilla
CVT- What causes severe osteolytic lesions (“punched out areas”) which are present in bones of the cranium?
Multiple myeloma
CVT- What causes thickening and increased opacity (hyperosteosis) of calvarium (arrow)?
Meningioma
What is a chronic progressive disease in which longitudinal cavities form in the cervical region of the spinal cord. This characteristically results in wasting of the muscles in the hands and a loss of sensation?
Syringomyelia
An enlarged, dorsally projecting, foramen magnum characteristic of?
Occipital Dysplasia
Meningiomas are a diverse set of tumors arising from the meninges. (which are?)
They arise from the arachnoid “cap” cells of the arachnoid villi in the meninges. These tumors usually are benign in nature; however, a small percentage are cancerous
the membranous layers surrounding the central nervous system
What is is a malignant neoplasm derived from ceruminous glands of the external auditory canal called?
Ceruminous adenocarcinoma
This tumor only affects the outer 1/3 to 1/2 of the external auditory canal as a primary site. If this area is not involved, the diagnosis should be questioned. The most common tumor type is ceruminous adenoid cystic carcinoma and ceruminous adenocarcinoma, NOS
extrathoracic sounds vs. intrathoracic sounds?
Extra- Stertor- snoring like noise in the naso or oropharynx. Sometimes supraglottic. Caused by obstruction
Stridor- harsh vibratory turbulent airflow thru a narrowed airway.
Intra-
Wheeze- expiratory flow limitation of intrathoracic airways. The airway walls flutter at the site of obstruction. If severe, there can be an inspiratory component. Or its really bad news if the wheeze disappears (no air passing thru).
• Wheezes can be monophonic (one central airway blocked) or polyphonic (several peripheral airways blocked) Intrathoracic obstruction is most severe during expiration and is relieved during inspiration. Extrathoracic obstruction is increased during inspiration because of the effect of atmospheric pressure to compress the trachea below the site of obstruction.
Inflammation and infection of nasal cavity- Fungal rhinitis causes osteolysis of nasal turbinates in the ____ ____ of a nasal cavity and increased ST opacity in the _____ ____ with the ethmoid turbinates.
rostral portion
Caudal portion
(open mouth ventrodorsal rad)
Inflammation and infection of nasal cavity- Chronic rhinitis gives an increased opacity in both nasal passages w/o evidence of ____ _____.
bone distruction
Nasal neoplasia causes an increased ST opacity throughout affected cavity with _____ of the inner nasal septum (mid-vomer bone) and indistinct turbinate margins. A mass in the nasal cavity causing ______ and lateral deviation of the internasal septum.
osteolysis
osteolysis
(open mouth ventrodorsal rad)
Temporomandibular joint dysplasia causes what process to be abnormally shaped?
Retroarticular
What is the most common luxation of the TMJ?
Rostral- mandibular condyle is displaced rostally
Which process is abnormal in shape with a fracture luxation of the TMJ?
Retroarticular process
(this is a caudal subluxation and a lateral oblique rad)
What is this?
Peri-apical cemento-ossious dysplasia
