Test 2: lecture 10

Question 1

what transducer gives you a rectangle field

Answer 1

rectilinear array- used for superficial structures such as tendons

Question 2

what kind of transducer is good for abdominal ultrasound

Answer 2

curvilinear array

Question 3

what transducer is used for echos?

Answer 3

annular array (target pattern)

allows to go through ribs

Question 4

gain

Answer 4

turning up the brightness

general gain- brightness of overall image

Time gain compensation (TGC) - depth dependent brigthness

Question 5

Internal structure of organs
– homogeneous, coarse, mottled…

Answer 5

echostructure

Question 6

echogenicity

Answer 6

brightness of a tissue

hyperechoic

hypoechoic

isoechioic

anechoic - black at all gain (fluid)

Question 7

anechoic

Answer 7

black at all gains- fluid (urine in bladder)

Question 8

Answer 8

A1 is anechoic

A1 is hypoechoic to A2

B1 is isoechoic to B2

C1 is hyperechoic to C2

Question 9

reverberation artifact

Answer 9

when ultrasound is repeatedly reflected between two highly reflective surfaces (pocket of sound bouncing back and forth)

(air filled intestine)

ultrasound not good to look at normal lung

Question 10

what kind of artifact

Answer 10

reverberation artifact

air in intestine causes lines below that are obscuring everything below the bubble

Question 11

Answer 11

comet tail artifact -little bubbles of gas cause artifact

Question 12

acoustic shadowing

Answer 12

structure absorbs waves (stone, bones, foreign body) everything deeper to that object is darker

Question 13

edge shadowing

Answer 13

when wave hits border of curve structure with very different density than what is around it, wave will suddenly change position → darkness

gallbladder

Question 14

distal enchancement

Answer 14

used to find fluid filled structures

deeper portion is stronger because it went through fluid that did not echo the sound → the tissue deeper to a fluid filled structure is lighter then just tissue area

Question 15

This is a longitudinal section of the left adrenal gland in a dog. The caudal pole of the gland is outlined by the calipers. Compared to the area ‘1’, the adrenal gland is:

Answer 15

hypoechoic

Question 16

This is an ultrasound image of the stomach of a dog that has a gastric tumor: the wall is thickened (between calipers) and hypoechoic. Distal to this thickened wall, the type of artifact outlined by the arrows are:

Answer 16

Comet tail artifacts, a particular type of reverberation artifact

Question 17

This is an image of the common bile duct (CBD) in a cat with jaundice. The jaundice was caused by gallstones blocking the CBD. It shows:

Answer 17

Gall‐stones stuck in the CBD associated with acoustic shadowing

Question 18

This is a longitudinal section of an intestinal loop in a dog with diarrhea (between arrow‐heads). A long structures bordered by two hyperechoic lines is seen in the lumen of that intestinal loop. This was a parasitic worm causing the symptoms. What else is contained within the lumen of that intestinal loop?

Answer 18

Some sort of fluid

(fluid is dark/black)