Ultrasound Flashcards
Is image quality (resolution) directly or inversely related to the frequency of the sound wave in ultrasound?
Directly
Does ultrasound send more pulses to return or listen for more pulses to return?
Ultrasound listens for pulses to return more than it sends them
Which, a hemorrhagic cyst or an endometrioma, is more likely to resolve on its own?
Hemorrhagic cyst
How is a gallstone different from a polyp on ultrasound?
Gallstones move and create shadows
Five most common types of artifacts to occur in ultrasound
- Reverberation
- Shadow
- Enhancement
- Mirror image
- Refraction
Which, a gallstone or gallbladder polyp, is more likely to be found incidentally?
Polyp
(asymptomatic)
How to distinguish appendix from bowel on ultrasound?
Appendix won’t compress under pressure like bowel
A cyst with this type of boundary is more concerning for malignancy
Hypoechoic rim
(also blurred indistinct is worrying and maybe hyperechoic)
Can an ultrasound show heart anatomy?
Yes, with motion!
A string of pearls seen around the periphery of the ovary might suggest this condition
PCOS
Appearance of fluid on ultrasound
Black
Is depth of penetration directly or inversely related to frequency of the ultrasound wave?
Inversely
A cyst with this type of boundary is the least concerning for malignancy
Sharp, distinct border
What happens when any of the six assumptions of imaging systems is incorrect?
Artifacts in the image appear
If an ultrasound transducer is being held in the long position (indicator towards head) will the superior structures be shown on the left or right of the ultrasound screen?
Left
Stones on ultrasound can have this artifact
Twinkle artifact
Is an organ that appears lighter than surrounding tissue on ultrasound considered hyperechoic or hypoechoic?
Hyperechoic
Appearance of a trichobezoar on ultrasound
Air trapped around hair fibers causing the appearance of an echogenic arc with shadowing
Is a lesion that appears darker than surrounding tissue on ultrasound considered hyperechoic or hypoechoic?
Hypoechoic
Which chamber of the heart sits most anterior in the body?
Right ventricle
Most useful ultrasound technique for evaluating the endometrium in a retroflexed uterus
Transvaginal
Is doppler shift a higher or lower frequency than regular ultrasound?
Lower (within range of human hearing)
How long into pregnancy can you reliably see a gestational sac on transvaginal ultrasound?
4.5 to 5 weeks
Which parts of the body attenuate the most in ultrasound as it travels through the body?
Lung and bone
In ovarian pathology, how many papillary structures are needed to classify a tumor as malignant?
At least four
True or false. A healthy post menopausal woman should never have a thick, complex looking endometrium
True
If it looks this way, may be endometrial carcinoma
Do higher frequency waves have longer or shorter wave length?
Shorter
On ultrasound, a patient’s kidneys are seen to be 24cm in size and contain multiple cysts. What diagnosis might run in their family?
ADPKD (autosomal dominant polycystic kidney disease)
Four things required for a cyst to be called simple
“STAR”
- Smooth outer border
- Through transmission
- Anechoic
- Round/oval shape
Complication of pancreatitis that makes ultrasound difficult
Severe epigastric pain/tenderness makes it hard to push deep enough with transducer and move air from stomach out of the way
Ultrasound is above the human range of hearing, at this kHz
Above 20 kHz (20,000 Hz)
In terms of echogenicity, how will a fatty liver appear on ultrasound?
Hyperechoic/echogenic
Which transducer, a 12-5 or a 6-2, will give a sharper image with higher resolution?
12-5
Hepatic duct normal measurement
2 mm
Transvaginal ultrasound is the best technique to visualize a gestational sac within the uterus when hCG is at this level
1000 to 2000
Can an ultrasound show chest/thorax anatomy?
No really, air in lungs makes it difficult
What shape will the display of an L, P, and C transducer be on the ultrasound display?
L = linear, square image
P = pie, conical pie shape, point at top
C = curved, blunted pie shape
Which is typically larger, serous cystadenoma or mucinous cystadenoma?
Mucinous much larger
Which transducer, a 12-5, or a 6-2, will give a deeper image?
6-2
In a FAST scan lung ultrasound, what sign suggests pneumothroax?
Barcode/stratosphere sign, no motion
Six assumptions of imaging systems
- Sound travels in a straight line
- Sound travels directly to a reflector and back
- Sound travels in soft tissues at exactly 1,540 m/sec
- Reflections arise only from structures positioned within the main axis of the beam
- The imaging plane is very thin
- The strength of a reflection is related to the characteristics of the tissue creating reflection
A patient receiving a full bladder ultrasound should be instructed to do this before coming in
Drink lots of fluid, come with full bladder
What is the name for a large gestational sac (>18 mm) with no sign of a yolk sac?
Blighted ovum
Normal AP measurement of the aorta
< 3cm
Why are measurement calipers placed on the outer walls of blood vessels like the aorta when measuring, rather than just measuring the lumen?
To include any potential thrombus
In ovarian pathology a tumor is more likely to be malignant if it is multilocular, solid, and with a largest diameter measuring at least this many centimetres
At least 10 cm
What is the 10x10x10 rule in PCOS?
- Ovaries are enlarged >10 cm
- 10+ follicles in each ovary
- Follicles < 10 mm
Most common cause of uterine enlargement
Uterine leiomyoma
When utilizing contrast enhanced ultrasound to analyze a liver tumor, does a late and weak washout suggest hepatocellular (primary) cancer or metastasis from elsewhere?
Hepatocellular carcinoma
Tumor originated in the liver
Appearance of bone on ultrasound
Reflective, creates a shadow
In Doppler ultrasound, when a wave is bouncing back from an object moving towards the transducer have a higher or lower frequency?
Towards transducer = higher frequency
In hypertrophic pyloric stenosis, pyloric muscle will be this thick and the pyloric canal will be this long
Pyloric muscle thicker than 3 mm
Pyloric canal longer than 15 mm
At what point of the menstrual cycle will the endometrium appear thickest?
Start of menstrual cycle
Why is an anechoic cyst less concerning than an echogenic cyst?
Anechoic suggests fluid filled
Echogenic suggests tissue filled
Three parameters to make a sound wave
- Pressure
- Density
- Distance
What does a black gap seen between the liver and kidney suggest?
Morrison’s pouch
- free fluid in hepatorenal recess
Most common solid, malignant abdominal mass in children
Wilm’s tumor aka nephroblastoma
Which chamber of the heart lies closest to the spine/descending aorta?
Left atrium
When measuring a blood vessel, which view is typically more accurate, transverse or long (sagittal)?
Transverse
(better to look straight down the lumen)
What does isoechoic mean?
Adjacent structures are similar in echotexture (same shade of grey)
What should be present in the ovary in early pregnancy?
Corpus luteum cyst of pregnancy
Are superficial structures like the thyroid better viewed with a 12-5 or 6-2 ultrasound transducer?
12-5
Higher frequency = higher resolution and not much penetration needed for superficial structures
Normal right lobe of liver measurment
< 18 cm
In ovarian pathology, a tumor is more likely to be benign if ascites is absent, and the largest solid component is no larger than this many centimetres
No more than 7 cm
As hemorrhagic cysts resolve they begin to resemble this on ultrasound
Broken glass
Ultrasound method for analyzing degree of liver fibrosis
Elastography
When holding the ultrasound transducer in the transverse position over the aorta, will the vessel appear circular or seen side on?
Circular, looking down the lumen
Right and left kidneys should be the within this measurement of each other
Less than 1 cm difference in size between kidneys
How should a transducer and needle be aligned when doing ultrasound guided biopsy?
Needle should be parallel to the long side of the transducer
Renal cell carcinoma typically affects this area of the kidney whereas transitional cell carcinoma typically affects this area of the kidney
RCC = cortex of the kidney
TCC = collecting system
When utilizing contrast enhanced ultrasound to analyze a liver tumor, does a rapid and marked washout suggest hepatocellular (primary) cancer or metastasis from elsewhere?
Metastasis
Tumor needs lots of blood flow
Size range for normal kidneys on ultrasound
9 to 12 cm
A normal spleen should be this size
13 cm or less
If free fluid seen on ultrasound is not completely black, what might it contain?
Blood
Normal nulliparous uterus size
Up to 8 cm
Appearance of air on ultrasound
Reflective, creates a shadow
Appearance of soft tissue on ultrasound
Grey
When hCG is > 3600 you can see a gestational sac in the uterus on this ultrasound technique
Transabdominal
Normal common bile duct measurements in a normal person and a person who had their gallbladder removed or is older
Normal = 7 mm
GB removed/elderly = 11 mm
What does ALARA stand for?
As Low As Reasonably Achievable
(frequency = how often, not Hz)
Which parts of the body attenuate the least in ultrasound as it travels through the body?
Water and blood
What should a vein do when pressure is applied with a transducer than an artery wouldn’t?
Compress
Ultrasound uses this type of sound waves
Pulsed sound waves
What does a double decidua sign indicate?
Intrauterine pregnancy
Ways to differentiate aorta from IVC on ultrasound
Aorta:
- will pulse
- has branches
- dives posterior to heart
- sits left of midline
IVC
- less motion
- no proximal confluences (branches?)
- cusps the liver as it dumps into right atrium
- sits right of midline
