Random 11 Flashcards
Whenever the fissure for the ligamentum venosum is seen, the portion of the liver seen anteriorly must be the lateral segment / segment II of the left lobe.
Whenever the fissure for the ligamentum venosum is seen, the portion of the liver seen anteriorly must be the lateral segment / segment II of the left lobe.
- CBD
- RIGHT hepatic artery
- portal vein
- IVC
- right renal artery
- right diaphragmatic crus
- cystic duct insertion
- portal vein
- proper hepatic artery
- CBD
Transverse and longitudinal views of
the mediastinum of the testis
- head of epididymis - normally isoechoic to the testis
- body of epididymis - normally hypoechoic to the testis
6 scrotal layers
- skin
- dartos fascia
- external spermatic fascia
- cremasteric muscle
- internal spermatic fascia
- tunica vaginalis
- tunica albuginea - testicular capsule
- infolding of tunica albuginea becomes mediastinum
- left lobe of liver
- pancreas
- porto-splenic confluence
- aorta
- IVC
- SMA
- CBD
- gastroduodenal artery
The CBD travels in the most posterior aspect of the
pancreas. In fact, it often appears immediately anterior
to the IVC. The gastroduodenal artery arises from the
common hepatic artery and descends along the anterior
aspect of the head of the pancreas. These two structures
often appear as two small anechoic dots on transverse
views of the pancreatic head.
- left lobe of liver
- pancreas
- splenic vein
- aorta
- celiac axis
- SMA
- left renal vein
- gastric antrum
Which is closer to the pancreas,
SMV or SMA?
- SMV is immediately adjacent to the head and uncinate process of the pancreas; SMV is to the right
- SMA is separated from the pancreas by a ring of echogenic fibrofatty tissue; SMA is to the left
Grading of hydronephrosis
- Grade 0 - normal sonogram
- Grade 1 - minimal separation of the central echogenic renal sinus
- Grade 2 - obvious distention of the renal collecting system
- Grade 3 - marked distention of the renal collecting system with cortical thinning
- caudate lobe
- segment II/III
- segment IV
- large arrow - ligament teres
- small arrow - ligamentum venosum
DDx for focal decreased echogenicity in a tendon
- tendinitis
- partial tear
- anisotropy
- rotator cuff
- cartilage
- humeral head
- anatomic neck
- greater tuberosity
- subdeltoid bursa
- deltoid muscle
- biceps tendon
The intra-articular portion of the biceps tendon
separates the subscapularis and the supraspinatus.
The caudate lobe drains into the vena cava via
small veins that are separate from the three main
hepatic veins. The caudate veins can function as
collaterals in patients with Budd–Chiari syndrome.
The caudate lobe drains into the vena cava via
small veins that are separate from the three main
hepatic veins. The caudate veins can function as
collaterals in patients with Budd–Chiari syndrome.
- right thyroid lobe
- thyroid isthmus
- carotid
- IJV
- trachea shadow
- strap muscles
- sternocleidomastoid muscle
- longus coli muscle
The thyroid is more echogenic than the overlying strap muscles and the sternocleidomastoid muscles.
- thyroid
- strap muscles
- sternocleidomastoid muscle
- cartilage rings of trachea
Normal parathyroid glands are too small to be seen on US.
What muscles contribute to the Achilles tendon?
In what part of the tendon does rupture normall occur?
- The gastrocnemius and soleus muscles form the Achilles tendon
- Complete Achilles tendon tears usually occur 2-6 cm proximal to its insertion
DDx for testicular hyperemia
- orchitis
- shortly following detorsion
How to clinically differentiate testicular tumor from focal orchitis?
- testicular tumor - non-tender, palpable
- focal orchitis - tender, non-palpable
Location of thyroglossal duct cyst
- tract of the thyroglossal duct extends from foramen cecum (base of the tongue) –> hyoid bone –> thyroid isthmus –> pyramidal lobe
- 15% - at the level of hyoid bone, midline
- 65% - just below the hyoid bone, midline
- 20% - suprahyoid, tend to be off midline
- unlike cysts elsewhere, thyroglossal duct cysts are usually not anechoic
- low-level internal echoes
- due to hemorrhage, infection, crystals, or proteinaceous material
- non-parenchymal structures, such as extremities and bowel
- very narrow and sharply pointed systolic peak, rapid systolic deceleratio into diastole, and little, if any, late diastolic flow
- short phase of diastolic reversal is due to elastic recoild of the artery
- RI = PS-ED/PS close to 1 for high resistance
Ganglion cyst
- most common cause of palpable cysts in the wrist and hand
- most common in young women
- most common location - dorsal wrist, superficial to the scapholunate joint
- less common - volar wrist around flexor carpi radialis tendon or radial artery; along the flexor tendon sheaths of the fingers; arise from IP joint, usually due to degenerative OA
- containing very thick, gelatinous liquid
Acute Appendicitis
DDx for multiple hypoechoic liver lesions
DDx for multiple hypoechoic liver lesions
- metastases
- lymphoma
- multifocal HCC
- FNH, adenomas
- abscesses
- sarcoidosis
Testicular cysts
- when an intratesticular lesion meet criteria for a simple cyst, it requires no further evaluation
- 10% prevalence
- more common in elderly men
- often occur near the mediastinum
- associated with tubular ectasia of the rete testes - both conditions may be caused by outflow obstruction of the seminal fluid
Doppler Aliasing Artifact
- aliasing is due to a basic principle of sampling theory = a periodic phenomenon must be sampled at twice its own frequency to be accurately reproduced
- increase Doppler scale –> decrease aliasing
- decrease probe frequency –> decrease aliasing
- the frequency shift is proportional to the transmitted frequency
- scan at a larger Doppler angle –> decrease aliasing
Post-vasectomy epididymal enlargement
- most frequently visualized in the epididymal body
- causes of obstruction
- vasectomy
- trauma
- infection
Indications for thyroid biopsy
Indications for thyroid biopsy
- nodules > 1.5cm
- solid and hypoechoic
- irregular margins
- thick halo
- microcalcifications
Junctional parenchymal defect
Junctional parenchymal defect
- 20% of patients
- more common on the right
- triangular-shaped defect along the anterior renal surface at the junction of upper and middle third
- communicating with renal sinus fat
Testicular seminoma
- homogeneous, hypoechoic, hypervascular mass - typical for a seminoma
- DDx
- seminoma
- infarct
- contusion
- hematoma
- focal orchitis
- focal atrophy
- sarcoid
- primary tseticular tumors are the most common malignancy in young adults
- most common - germ cell tumors
- most common - seminoma
- most common - germ cell tumors
Kasabach-Merritt Syndrome
Kasabach-Merritt Syndrome
Platelet sequestration and destruction by hemangiomas - extremely rare cause of thrombocytopenia
Hemangiomas can change over time, even during real time scanning!
Hemangiomas will occasionally
change in appearance over time. Typically, they
will convert from hyperechoic to hypoechoic. Rarely,
they will change echogenicity over a matter of minutes
or even seconds. No other hepatic mass has been
observed to have this behavior.
Exact location of a Baker’s cyst
Baker’s cysts occur in the medial aspect of the
posterior knee. The cyst arises from fluid accumulation
in the bursa between the medial head of the
gastrocnemius and the semimembranosus tendon.
Upper limit of normal for peripheral intrahepatic ducts
is 2mm
Upper limit of normal for peripheral intrahepatic ducts
is 2mm
US appearance
gallstones
vs
sludge ball
vs
polyp
- gallstone - echgoenic, mobile, shadowing
- sludge ball - echogenic, mobile, non-shadowing
- polyp - echogenic, non-mobile, non-shadowing
Epididymal cystic lesion
- spermatocele - more common
- epididymal cyst - contains serous fluid
Pathogenesis of alcohol pancreatitis
Alcohol causes precipitation of proteins that obstruct the ducts, and gallstones produce obstruction when they pass through the bile duct and lodge at the ampulla.
Varicocele
Varicoceles are dilated veins of the pampiniform
plexus. They are almost always caused by incompetent
valves within the internal spermatic vein.
Normal peritesticular veins should
be less than 2 or 3 mm in diameter. In my experience,
they seldom exceed 2 mm. On color Doppler scanning,
venous flow in varicoceles is generally too slow to be
detected with the patient at rest. Sometimes, this slow
flow is apparent on gray-scale imaging. With a Valsalva maneuver, there is augmented retrograde flow in the varicocele that is readily detectable on color Doppler imaging. This augmented flow usually lasts longer than 1 second.
Postcatheterization Pseudoaneurysm
Postcatheterization Pseudoaneurysm
- The waveform exhibits pandiastolic flow reversal. The normal triphasic pattern has only a short period of flow reversal in early diastole.
- “To-and-fro” waveform comes from the neck of a pseudoaneurysm and reflects flow into the aneurysm during systole and flow out of the aneurysm during diastole.
- Color Doppler - “yin-yang” appearance
- With grayscale imaging - often possible to see the collection expand during systole and contract during diastole.
- DDx - hematoma, abscess, adenopathy, and hernia.
- Rx - ultrasound-guided thrombin
injection.
Replaced right hepatic artery
- Normally right hepatic artery runs anterior to the portal vein
- If there is an artery runs b/t the PV and IVC, it is most likely to be an anomalous right hepatic artery arising from the SMA
- Incidence of replaced or accessory right hepatic artery = 20%
Column o Bertin
Column of Bertin
Normal portal vein waveform
Normal portal vein waveform
- normal portal vein velocity - 15-30 cm/sec
- Although the liver is very close to the heart, the hepatic parenchyma and its sinusoidal network effectively isolate the portal vein from the pressure fluctuations in the right heart. For this reason, the portal vein waveform is much less pulsatile than other centrally located veins. However, the normal portal vein waveform usually does have some gentle pulsatility related to the cardiac cycle.
- A good rule of thumb is that minimum flow velocities should not drop all the way to the baseline and certainly not below baseline.
DDx for
- porcelain gallbladder - clean shadow
- emphysematous cholecystitis - dirty shadow
- as well as ring down artifact
- only gas can give you ring down artifact! (maybe metal also)
- can be differentiated with AXR or CT
DDx for polypoid nonshadowing lesion in the gallbladder?
- gallbladder polyp
- gallbladder cancer
- tumerfactive sludge
- pus
- blood clots
can use Doppler flow to distinguish
Cholesterol polyps
- usually pedunculated
- most common gallbladder polyp
- enlarged papillary fronds filled with lipid-laden macrophages - a form of gallbladder cholesterolosis
- “ball on the wall” sign
- does not appear to be associated with an increased incidence of cholesterol stones
Mirror artifact
- air in the lung base and air in the trachea acts as an acoustic mirror
Vertebral artery
This abnormality is caused by stenosis of the
subclavian artery prior to the origin of the
vertebral artery.
Morton’s neuroma
Morton’s neuroma
- arise from plantar branch of the digital nerves
- most often located in the 2nd and 3rd webspaces of the foot at the level of the metatarsal heads
- more common in women
- due to perineural fibrosis, likely related to repetitive trauma
- pain and paresthesias with walking and marked tenderness to direct palpation
- hypoechoic masses
Tenosynovitis
An effusion with thickening and increased vascularity
of the tendon sheath around the tendon.
Papillary thyroid cancer
Psammoma bodies (microcalcifications)
Papillary thyroid cancer
Psammoma bodies (microcalcifications)
- Cysts of the tunica albuginea are entities distinct from intratesticular cysts.
- Typically, they are very firm on physical examination and often are first recognized by the patient.
- Since they arise from the tunica albuginea, they are always located at the periphery of the testis.
- Although they occur in a range of sizes, they are most often less than 5 mm in diameter.
Hepatic target lesions
Hyperechoic centrally and hypoechoic peripheral rim
DDx
DDx for hepatic target lesions
Hyperechoic centrally with hypoechoic peripheral rim
DDx
- metastases
- HCC
- lymphoma
- abscess
The hypoechoic rim represents viable tumor. In fact, when performing percutaneous biopsy of these lesions, the highest yield is from the hypoechoic rim.
Ring down artifact causes
Causes of ring down artifact
- gas bubbles - msot common
- metal (cholecystectomy clips)
If a complex fluid collection gives ring down artifact - abscess containg gas locules
If echogenic gallbladder wall gives shadowing and ring down - emphysematous cholecystitis
If ring down in the gallbladder fossa following cholecystectomy - surgical clips
Hepatic abscesses can appear as solid lesions on US
Look for
target lesion appearance and
relative posterior acoustic enhancement
Hepatic abscesses can appear as solid lesions on US
Look for
target lesion appearance and
relative posterior acoustic enhancement
Normal hepatic vein waveform
Normal hepatic vein waveform
During right atrial contraction there is a short period during which the blood flow in the hepatic vein actually reverses and heads back into the liver. This is seen as the short phase of flow above the baseline. As the right atrium relaxes (corresponding to ventricular systole), blood flow rapidly exits the liver and enters the atrium, producing flow below the baseline. As the atrium starts to fill up, the flow out of the liver slows, and the waveform starts to approach the baseline. Then the tricuspid valve opens (at the beginning of ventricular diastole), and the right atrium starts to decompress into the right ventricle. This leads to another period of rapid outflow from the liver into the right atrium, resulting in a second pulse of flow below the baseline. Finally, the right atrium starts to
contract again, and the process repeats itself. The end
result is a triphasic pattern with one retrograde pulse
above the baseline (during atrial contraction) and two
antegrade pulses below the baseline. The first antegrade pulse is usually the largest and occurs during ventricular systole. The second antegrade pulse is usually smaller and occurs during ventricular diastole.
Replaced left hepatic artery
The left hepatic artery occasionally arises from the
left gastric artery. In such cases, it enters the liver
through the fissure for the ligamentum venosum.
Multilocular cystic nephroma
- a benign renal neoplasm.
- consists of multiple cystic spaces that do not communicate with each other or with the renal collecting system. The cysts are epithelium lined and separated by fibrous septations. The lesion is usually well encapsulated.
- demographics:
- young boys (typically 3 months to 4 years of age)
- adult women (older than age 30 years)
- surgical resection due to overlapping appearance with cystic RCC
Significance of this finding?
Spectral broadening
- can be a sign of disordered or turbulent blood flow
- but can be typical of small parenchymal vessels
- This difference is at least
partially related to the relative size of the vessel and the size of the sample volume. In a small vessel, the slow flow at the edge of the vessel wall and the faster flow in the center of the lumen are being sampled simultaneously.
In a larger vessel, only the faster flow in the
center is being sampled. In addition to large sample volumes, high Doppler gain and high power outputs can also produce spectral broadening in normal vessels.
- This difference is at least
What does this indicate?
- in the proper clincial setting, it indicates a proximal arterial stenosis
*
GIST
- 10-30% malignant
- C-KIT positive
- may have cystic necrosis, hemorrhage, calcifications
- the tumors grow in an exophytic fashion and this can make if difficult to determine
where the lesion arises. This growth pattern is particularly true of large lesions. Therefore, it is important to include GIST in the differential diagnosis of large intra-abdominal masses that do not arise from a defined solid organ.
Adenomatoid tumor
- benign
- most common location - epididymis
- homogeneous and small; may be hypo-, iso-, or hyper-echoic to the testis
- DDx
- inflammatory mass
- post-inflammatory scar
- sperm granuloma
Bladder diverticulum
- Which population?
- Complications?
- Further imaging?
Bladder diverticulum
- more common in older male (BPH)
- complicatiosn - stasis, stone, infection, cancer
- further imaging - often associated with bladder outlet obstruction, therefore post void residual is indicated
Thyroid follicular adenoma/carcinoma
- solid, homogeneous
- features: a thin, uniform, hypoechoic halo surrounding the tumor
FNH
- a collection of vessels arranged in a spokewheel configuration.
- Central calcification suggests the diagnosis of fibrolamellar hepatocellular carcinoma and would prompt a more aggressive approach.
- NM study - sulfur colloid scan - Due to the concentration of Kupffer cells, approximately 60% of FNHs are either
more intense or isointense to adjacent liver.
Peyronie’s disease
Peyronie’s disease is fibrosis of the tunica albuginea of
the corpora cavernosa.
