Head/neck (not including brain) Flashcards
What are the 5 classifications for caudal aberrant turbinates in English bull dogs?
Vilaplana, F., et al. “Gender, weight, and age effect on prevalence of caudal aberrant nasal turbinates in clinically healthy english bulldogs” Vet rad 2015 (pre-publish)
- No turbinates in ventral nasal meatus
- Turbinates in VNM, but not nasopharyngeal meatus
- Turbinates in NPM, but not extending into choanae
- Turbinates in choanae but not to the rostral border of the nasopharynx
- Turbinates visible in the nasopharynx
According to the article “Gender, weight, and age effect on prevalence of caudal aberrant nasal turbinates in clinically healthy english bulldogs” - what is prevalence of caudal aberrant nasal turbinates in healthy English bull dogs? What is significance of grades 0-3?
Prevalence is 100% in these healthy dogs (no signs of respiratory disease). These dogs were scored 1-3. No significance of gender, weight, or age. Suggests that severe cases are grade 4 - but more studies needed!
How are the nasal conchae form, and what problem occurs in English bulldogs that lead to caudal aberrant turbinates?
Vilaplana, F., et al. “Gender, weight, and age effect on prevalence of caudal aberrant nasal turbinates in clinically healthy english bulldogs” Vet rad 2015 (pre-publish)
Post-natal development and growth of the nasal conchae is normal in healthy animals - conchae grow until the nasal cavity is occupied. In brachycephalic breeds - mechanisms fail, favourin aberrant extension of conchae (they do not stop growing once they touch each other).
Which imaging characteristics were pathognomonic for carcinoma vs sarcoma vs melanoma of the pharynx?
Carozzi, G., “CT features of pharyngeal neoplasia in 25 dogs.” VRU Pre-publish.
NONE. (shape, margins, mass effect, infiltration, grade/pattern of enhancement, potential distant metastasis, enlargement/shape, enhancement of lymph nodes.”
What characteristics of lymph nodes were consistent with metastatic disease from a pharyngeal neoplasia. What % of lymph nodes with these findings were consistent with metastasis?
Which lymph node was most commonly affected?
Carozzi, G., “CT features of pharyngeal neoplasia in 25 dogs.” VRU Pre-publish.
Enlarged, round, heterogeneous contrast enhancement.
75%
Medial retropharyngeal lymph nodes. Mandibular lymph nodes also were commonly affected, but to lesser degree.
According to the article: Apparent wall thickening in fluid filled vs air filled tympanic bulla in CT - what is ideal protocol and algorithm to view the tympanic bulla?
VRU 34.6
It is best to use a bone algorithm (with a very wide window - between 2 and 4000), with thin slices to prevent volume averaging
What algorithms/windows will make the tympanic bulla appear thicker?
Will fluid or air in the bulla make it look thicker?
Apparent wall thickening in fluid filled vs air filled tympanic bulla in CT. VRU 34.6
Soft tissue algorithm/window, thicker slices, narrow windows,
Fluid will make the bulla look thicker
What are high spatial frequency objects?
Apparent wall thickening in fluid filled vs air filled tympanic bulla in CT. VRU 34.6
Small size, well defined borders, high degree of contrast with surrounding structures.
Examples: Bone, pulmonary vessels, pulmonary nodules
What are low spatial frequency objects?
Apparent wall thickening in fluid filled vs air filled tympanic bulla in CT. VRU 34.6
Large size, poorly defined borders, low contrast with surrounding structures.
Examples: Abdominal viscera and fat.
What happens to the bulla when fluid is added into the tympanic cavity? (relate to the high/low spatial frequency of these objects)
Apparent wall thickening in fluid filled vs air filled tympanic bulla in CT. VRU 34.6
The bulla will appear thicker.
Tympanic bulla is a high spatial frequency structure (thin walled, small, high contrast with air in the cavity). When fluid cavity - there is less contrast and spatial frequency decreases and information is transferred better. (IE - HU # of bulla will be closer when fluid filled than when air filled)
What are indications for evaluation of the nasolacrimal system?
chronic epiphora, orbital trauma, nonresponsive conjunctivitis, proptosis, congenital malformations, neoplasia, factial fractures
What are the components of the nasolacrimal drainage system?
CT anatomy of normal feline nasolacrimal drainage system VRU 47.1
upper and lower lacrimal puncta, lacrimal canaliculi, lacrimal sac, and nasolacrimal duct
What are the osseous structures in vicinity of drainage system of nasolacrimal duct?
CT anatomy of normal feline nasolacrimal drainage system VRU 47.1
lacrimal fossa,
Which part of the lacrimal system is not covered by osseous structures?
CT anatomy of normal feline nasolacrimal drainage system VRU 47.1
the lacrimal sac (approximately 2mm) - between lacrimal and maxillary bones. Approximately 2mm rostral to the maxillary recess
Where is the origin of the nasolacrimal duct at approximately?
CT anatomy of normal feline nasolacrimal drainage system VRU 47.1
At the same level of the infraorbital foramen - at the caudal border of the maxillary 3rd premolar
What surrounds each portion of the nasolacrimal duct? (proximal, middle, distal)
CT anatomy of normal feline nasolacrimal drainage system VRU 47.1
Proximal - maxillary bone
Middle - ventral to basal lamina of the ventral nasal concha. Medial portion covered by respiratory epithelial mucosa
Distal - runs towards midline without osseous protection.
Whole canal is formed by maxilla and the basal lamina of ventral nasal concha
At what level could the lacrimal sac be identified?
CT anatomy of normal feline nasolacrimal drainage system VRU 47.1
At the level of the maxillary foramen (caudal end of infraorbital canal).
What are the 5 types of paragangliomas in the head and neck? (NOT SUBGROUPS)
CT and MR features of carotid body paragangliomas in 16 dogs. VRU 56.4
1) Carotid body tumors - paraganglioma cells at the carotid bifurcation
2) Vagal paragangliomas - arise from paraganglionic tissue within the vagal nerve (near skull in the jugular fossa)
3) Tympanic paraganglioma - tympanic branch of glossopharyngeal nerve (anyhwere aong this nerve)
4) Jugular paraganglimomas within adventitia of jugular bulb
5) Chemodectomas - aortic bodies
Where is the most common form of paragangliomas located at?
CT and MR features of carotid body paragangliomas in 16 dogs. VRU 56.4
aortic bodies - close to heart base, less commonly at bifurcaiton of common carotid vessel
What is typical behavior of paragangliomas?
CT and MR features of carotid body paragangliomas in 16 dogs. VRU 56.4
Slow growing, nonsecreting tumors, 30% of dogs have metastasis at time of diagnosis (lungs, nodes, liver, pancreas, kidneys and vertebrae).
What breed and sex are predisposed to paragangliomas?
CT and MR features of carotid body paragangliomas in 16 dogs. VRU 56.4
Brachycephalics (boston terriers specifically)
Males
What are common characteristics of paragangliomas? (Both CT and MR)
CT and MR features of carotid body paragangliomas in 16 dogs. VRU 56.4
1) Splaying of carotid bifurcation
2) Lateral/ventrolateral displacement of external carotid vessels
3) Entrapment of external carotid artery
4) strongly contrast enhancing (usually homogeneous)
5) similar to musculature on CT, hyperintense on MRI
6) T2* hemorrhage
7) Invasion into adjacent structures 9/16 dogs