Prelim TQs Flashcards
(605 cards)
What are the normal size for adrenal glands on U/S for dogs based on weight (< 10kg, 10-30kg, > 30kg)?
< 10 kg = 0.54cm
10-30kg = 0.68cm
> 30 kg = 0.80cm
Which cells of exocrine pancreas produce glucagon?
A) Alpha cells
B) Beta cells
C) D cells
D) F cells
Answer = A
Alpha = glucagon
Beta = insulin
D cells = somatostatin
F cells = pancreatic polypeptide
In U/S of the thyroid gland, you encounter a hypoechoic nodule within the parenchyma which you suspect may be a normal parathyroid gland. What is the PPV that this is true on histopathology? What is an alternative DDX for this structure?
74% that the nodule is truly a parathyroid gland (74% PPV)
A small percentage of these nodules will actually be LOBULAR THYROID TISSUE/THYROID LOBULES
A dog presents for a cervical U/S. Bloodwork shows elevated ionized calcium. rDVM PTHrP is positive. What finding do you expect to see associated with the parathyroid glands?
A) Bilaterally enlarged parathyroid glands
B) Unilateral enlargement of the parathyroid glands
C) All parathyroid glands will be inconspicuous or absent
D) A mixture of big and small parathyroid glands
Answer = C
With hypercalcemia of malignancy ALL parathyroid glands will be small.
Where does the neurohypophysis originate from?
The floor of the hypothalamus
What are the 7 hormones released by the hypothalamus?
1) Corticotrophin releasing hormone
2) Thyroid releasing hormone
3) Gonad releasing releasing
4) Prolactin releasing hormone
5) Prolactin inhibitory hormone
6) Growth releasing hormone
7) Growth hormone inhibitory hormone
The inner dural/meningeal layer of the hypophysis (pituitary gland) forms what?
Diaphragma sellae
Which lobe is the posterior lobe of the hypophysis?
A) Adenohypophysis
B) Neurohypophysis
B) Neurophypophysis
What 2 hormones are produced by the neurohypophysis?
1) Oxytocin -> uterine and udder smooth muscle contraction
2) Vasopressin/antidiuretic hormone -> vasoconstriction & fluid resorption by kidneys
What structure arises from the roof the mouth (Rathke’s pouch)?
Adenohypophysis
T or F, the adenohypophysis has NO direct vascular connection to the hypothalamus?
FALSE
Adenohypophysis has DIRECT vascular connection to hypothalamus
What signal intensity is the pituitary gland on T1 images?
HYPERintense due to vasopressin granules
Using dynamic CT for assessment of pituitary-dependent Cushing’s, what is the expected attenuation of the gland with a microadenoma?
Microadenoma often ISOattenuating to rest of pituitary parenchyma
Using dynamic contrast enhanced CT for pituitary adenomas, what is the characteristic feature?
A) Microadenomas are either hypo- or hyperattenuating to rest of gland
B) Displacement of pituitary flush
C) Marked early enhancement of the mass
D) None of the above
Answer = B
Some masses have diffusely abnormal enhancement.
Pituitary flush is STRONGER in normal glands. With adenomatous hyperplasia or mass formation, the flush will be displaced, distorted, smaller, or absent
What is the NORMAL brain to pituitary ratio?
A) Less than or equal to 0.31
B) Greater than or equal to 0.31
C) Less than or equal to 0.52
D) Greater than or equal to 0.52
Answer = A
Ratio MAY BE INCREASED if mass present
Which portion of the pituitary gland enhances first following contrast administration?
Neurohypophysis in the CENTER enhances first followed by peripheral adenohypophysis
Describe the pattern and type of enhancement (homogeneous versus heterogeneous) of the NORMAL feline hypophysis?
Homogeneous enhancement
2 patterns: central then peripheral (seen in 4 cats) or dorsal/peripheral then central (seen in 4 cats)
What is the optimal window width and window level for evaluation of the pituitary gland at the brain:pituitary edge and pituitary:bone edge, respectively?
A) WW/WL 80/250 & 240/250
B) WW/WL 240/250 & 80/250
C) WW/WL 250/240 & 250/80
D) WW/WL 250/80 and 250/240
Answer = D
WW 250 WL 240 for bone pituitary edge
WW 250 WL 80 for brain pituitary edge
Overall BEST window is WW 250 WL 80
What is the correct pattern indicative of restricted diffusion on DWI/ADC?
A) DWI hypo/ADC hyper
B) DWI hyper/ADC hypo
C) DWI hyper/ADC normal
D) none of the above
Answer = B
Restricted diffusion on DWi/ADC maps usually indicates what kind of edema and is associated with what disease process?
Cytotoxic edema
Associated with acute ischemic infarcts
Describe the appearance of unrestricted diffusion on DWI/ADC maps, what kind of edema is it associated with, and what disease process does it indicate?
Unrestricted diffusion = DWI hypo, ADC hyper
Associated with VASOGENIC edema & indicates tissue cavitation in chronic infarcts
Describe DWI/ADC “pseudonormalization”….Additionally, What kind of edema and disease process is it associated with?
DWI hyper, ADC NORMAL
Corresponds to concomitant cytotoxic & vasogenic edema in SUBACUTE infarcts
Which of the following cranial nerves is NOT involved in the oropharyngeal phase of deglutition?
A) CrN 5
B) CrN 9
C) CrN 11
D) CrN 12
Answer = C
CrN 5,7,9, 10, & 12 are associated with deglutition
What 2 muscles make up the cranial esophageal sphincter?
Cricopharyngeus & Thyropharygeus