Ultrasound Flashcards
RFs for gallbladder carcinoma
Chronic cholecystitis (gallstones seen in most cases)
Underlying conditions: PSC, IBD (UC>Crohns)
Ethnicity (native americans)
FHx
Obesity, diabetes
Most common GB met
Melanoma
DDx. diffuse GB wall thickening
- Fluid overload: CHF, cirrhosis, hypoproteinemia (malnutrition), renal disease
- Inflammatory/infectious: Cholecystitis (acute and chronic), hepatitis, pancreatitis, etc.
- Infiltrative neoplastic disease: GB carcinoma, mets
- Post-prandial state
Risk factors for cholangiocarcinoma
- PSC (major risk factor in NA)
- RPC (asians)
- Choledocholithiasis
- Asian liver flukes
- Caroli disease/choledochal cysts
- Viral hepatitis
- Toxins
Most common US finding in viral hepatitis
Normal!!
Other findings: starry sky (echogenic portal triads), diffuse GB wall thickening
Ddx for hyperechoic mass in liver
- Hemangioma
- Hepatoma
- Mets (CC - 50%, RCC, breast, NETs, chorioCa)
- Fat containing HCC
US appearance of FNH versus adenoma
FNH - “stealth” lesion - difficult to detect, may have spoke-wheel configuration of vessels in central scar
Adenoma - can look like anything, hypo->hyperechoic (due to presence of fat), hypoechoic halo often seen
Ddx calcified liver mets
Colon Ca (esp mucinous subtype) Gastric adeno
Ddx cystic mets in liver
Ovarian Colorectal NET - classically have fluid fluid level Pancreatic adenoCa Melanoma
Which malignancy gives the pseudo-cirrhosis appearance of the liver
Treated breast Ca
Cause of increased and decreased hepatic vein pulsatility
Increased: Tricuspid regurgitation (accentuated A wave, reduced S wave), right-sided HF (accentuated A wave, normal S wave)
Decreased: Cirrhosis, Budd-Chiari (hepatic vein thrombosis), hepatic veno-occlusive disease (bone marrow transplant, chemo causing fibrosis of sinusoids)
Causes of pulsatile waveform in PV
Anything that causes transmitted pulsations
- TR, right sided HF
- AV shunt (cirrhosis), AV fistula (HHT)
Doppler findings in portal HTN
Low PV velocity (<16 cm/s)
Dilated main PV >14 mm
Hepatofugal flow
Portosystemic shunts
DDx: hypoechoic splenic lesions
Sarcoid Mets Lymphoma Abscess Infarct
US findings RVT post-transplant
Reversal of diastolic flow in RA (but can also be seen with allograft torsion, rejection, ATN)
Upper limit velocities in renal transplant
PSV 340-400 cm/sec at anastomosis
Other signs: delayed/blunted systolic upstroke downstream (tardus-parvus waveform), reduced RIs
List the values for grading carotid stenosis
Normal
<50%: visible plaque, but PSV<125 cm/s; ICA/CC PSV <2; end diastolic ICA<40 cm/s
50-69%: visible plaque, PSV125-230 cm/s; ICA/CC 2-4; end diastolic ICA 40-100 cm/s
>70% (but no near occlusion: PSV>230 cm/s; ICA/CC >4; end diastolic ICA >100 cm/s
Appearance in near occlusion of ICA in carotid stenosis?
- markedly narrow lumen on color and power Doppler
- slow and dampened (pseudovenous) flow velocity
- systolic spikes with absent or reversed diastolic flow (distal stenosis and occlusion can also have this appearance)
Doppler velocity cannot be relied upon to identify near-occlusion, especially with only partial collapse, where the peak systolic velocity may be misleadingly normal or elevated
Causes of renal artery stenosis
Atherosclerosis - most common FMD - second most common - younger, distal RA Vasculitis - PAN, takayasu NF1 - usually at the osmium Aorta - coarctation/dissection
Causes of elevated RIs in the kidney
Native kidney:
- medical renal disease
- obstruction
Transplant kidney:
- ATN
- Acute or chronic rejection
- Renal vein thrombosis
- Obstruction
- Drug toxicity
*Decreased RI seen in RAS (downstream from stenosis the velocities are decreased)
PSV for diagnosis of RAS
> 200 cm/s (or renal artery to aorta velocity ratio >3.5)
Key consideration for cystic node in neck on US
Papillary thyroid carcinoma versus SCC
Most common type of uterine malformation
Septate - also most likely to have miscarriage
Most common renal anomalies associated with MDA
Renal agenesis (most common)
Crossed fused renal ectopia
Duplex kidney
List the subtypes of Mullerian duct abnormalities
Uterine agenesis/hypoplasia
Unicornuate (+/- horn)
Didelphys (separate uterus/cervix) - 75% vaginal septum
Bicornuate (partial - 1 cervix, complete - 2 cervix)
Septate (partial or complete) - convex fundus
Arcuate (small inpouching at fundus)
DES (T-shaped) - associated with clear cell vaginal ca
US cut-off for endometrial thickness
Pre-menopausal: up to 16 mm in secretory phase
Post-menopausal: bleeding <5mm, not bleeding can be 8-11 mm (controversial, can follow or refer to gyn)
** Cut off still 5 mm if on tamoxifen
DDx theca-lutein cysts
Elevated bHCG - molar pregnancy, multiple gestations, infertility drugs (clomiphene)
F/u of simple cysts in asymptomatic pre and post-menopausal women (on ultrasound)
Pre-menopausal
<3 cm, ignore
3-5 cm, report
>5 cm, follow (can use >7 cm if well visualized)
Post-menopausal
<1 cm, ignore
1-3 cm, report
>3 cm, follow (can use >5 cm if well visualized)
**only applies to simple, f/u in 1 year
if any complexity, shorter follow up (2-6 months)
F/u of hemorrhagic cysts (if typical appearance)
In pre-menopausal:
<5 cm report, no f/u
>5 cm, short interval f/u
In peri-menopausal, any size need f/u
In post-menopausal, surgical referral
Recommend f/u in 8 weeks (i.e. 2 cycles)
Criteria for diagnosing PCOS
If >8 years post-menarche:
>20 follicles, volume >10 cc
String of pearls, echogenic/hyperemic stroma
(if only in single ovary, still dx. of PCOS)
Risk of malignant transformation of dermoid
1-2%, usu SCC (from epithelial elements)
Inc risk in older pt (post-menopause) and large size
Types of primary ovarian malignancy
Epithelial stromal tumours (serous, mucinous, endometroid, clear cell, Brenner) - 60-70%
Germ cell (teratoma - mature, immature, struma ovarii; yolk sac; dysgerminoma; chorioCa) - 20%
Sex cord-stomal (fibrothecoma, sertoli-leydig, granulosa cell tumours - estrogen secreting) - 8-10%
Commonest malignant ovarian tumour
Serous cystadenocarcinoma
Commonest malignant sex cord tumour
Granulosa cell tumour of ovary
Most common tumours to metastasize to ovaries
Gastric/colon (Krukenberg) and breast**
Findings in Meigs syndrome
Ovarian fibroma, ascites, and right pleural effusion
Differentiating features between serous and mucinous ovarian tumours
Serous - unilocular, smaller, calcs, often bilateral, peritoneal mets
Mucinous - multilocular/honeycomb, large size, no calcs, usually unilateral, high T1 signs, may have pseudomyxoma peritonei
Distinguishing features in endometroid ca
Synchronous endometrial hyperplasia or carcinoma
Signs of endometriosis, bilateral in up to 40% of cases
Ddx for solid ovarian tumour
Fibroma - hypoechoic/low T2
Fibrothecoma - areas of high T2 and enhancement
Brenner - hypoechoic, most have associated calcs
Other: pedunculated/exophytic fibroid, met
Follow-up gallbladder polyps
<6 mm: no follow-up required
7-9 mm: high-risk patients (patient age >50 years, PSC, Indian ethnicity, sessile, and single polyps) should be performed at 6 months, 12 months, then yearly if the patient is a surgical candidate
> 1 cm: surgical referral
