Ultrasound Flashcards
First trimester bleeding
Gestational Trophoblastic Neoplasm (Complete Mole)
typical appearance of a cystic endometrial mass w/ “swiss cheese endometrium,” is seen in this case. nce of increased vascularity within and surrounding the mass is also typical of gestational trophoblastic neoplasia (GTN). Complete mole is the most common type of GTN.
—> Pseudomole can look similar with hydropic changes/sonolucencies in the uterus but shouldn’t have internal flow
—> perigestational hemorrhage should also have a normal gestational sac
12 weeks pregnant w/bleeding
IUP and this
Perigestational Hemorrhage
internal echoes within the fluid collection seen best on the transvaginal images.
The amnion has not yet fused with the chorion and the fluid collection lies between the chorion and the uterine wall.
PGH often lenticular and extends from the placental edge
—> Chorioamniotic separation appears as anechoic fluid between the amnion and chorion (our case hasn’t fused yet)
—> pseudogestational sac (seen w/ectopic sometimes) is round or tear-drop shaped and is a single fluid collx in the uterus. NO normal IUP/gestational sac
at what crown rump length can an embryo without heartbeat be called “not viable”
7mm
if it is smaller, need f/u to determine
First trimester bleeding
Cervical Ectopic
Assess for an “hourglass” shape of the uterus (the body of the uterus is the superior bulge; the cervix, distended by the ectopic pregnancy, creates the inferior bulge). The internal os is closed.
W/spontaneous abortion, sac will be central in the cervical canal, not implanted in the wall. W/c sx scar, will be implanted anteriorly in the low uterus and there will be no space between gestational sac and the bladder
Tubal Ectopic
echogenic adnexal ring (calipers) is highly suspicious for tubal ectopic pregnancy. A small amount of fluid but no gestational sac is seen within the uterine cavity.
“pregnancy of unknown location” only used when there is a positive pregnancy test but no evidence of an intra- or extrauterine gestation on vaginal ultrasound The right ovary is normal without evidence of a hemorrhagic cyst.
first trimester bleeding
Interstitial (cornual) ectopic
On the transvaginal transverse ultrasound of the uterus, the nondistended endometrium can be followed to the gestation in the cornua of the uterus (the interstitial line sign). Very thin, if any, myometrium is present on the other side of this sac .
marked vascularity also
Elevated HCG and bleeding
Invasive Mole: GTN
Gestational trophoblastic neoplasms may be 1 of the following subtypes: complete hydatidiform mole, invasive mole, choriocarcinoma, and partial mole. Complete hydatidiform moles may progress to invasive moles where the myometrium is invaded, or to choriocarcinoma, which is a malignant form of molar pregnancies with metastases commonly seen to lung and liver. Patients are treated with suction evacuation of the mass and with methotrexate or other chemotherapy
Complete moles Diploid, partial are Triploïd and have some fetus (all dad, all bad, etc)
34F with LLQ pain
Paraovarian Cyst
Simple unilocular cyst adjacent to the ovary which doesn’t change with time
—> can cause torsion of the broad ligament which presents similar to ovarian torsion and is managed surgically
—Serous cystadenoma can look similar but would arise from the ovary/may distort ovary
POD 1 with dropping hematocrit
large perinephric hematoma
Dilated ureter and finding
what are common artifacts seen with this condition?
Uretovesicular junction stone
—> posterior shadowing is most specific
—> twinkle artifact is also common
—> note absent right jet
No vascular flow on Doppler, patient p/w painless jaundice and acholic stool
Biliary Ductal Dilatation
US signs in Renal Vein thrombosis?
Enlarged, hypoechoic/edematous kidney
absence of flow in MRV and thrombus in vein are most specific
obstruction of venous outflow can lead to reversal of arterial diastolic flow
^RI
*tardus parvus is seen in renal arterial stenosis, upstream
Things that increase RI in kidney?
Decrease?
Increased seen in cases where it is harder for blood to get into the kidney :
ATN/AKI
hypoperfusion
Decreased seen with :
Renal artery stenosis
Tardus parvus –
what is each part and what does it tell you
Phenomenon observed downstream to sites of arterial stenosis
Useful for renal artery stenosis (will also get lower RI)
due to reduced magnitude of blood flow through narrowed vessel during systole
tardus: prolonged systolic acceleration (i.e. slow upstroke)
parvus: small systolic amplitude and rounding of systolic peak
Normal flow velocity Portal Veins?
Waveforms?
normal 20-40
10 or below PH
Also waveforms:
biphasic (if it dips below baseline, or if it is reversed (hepatofugal flow)
little bit of pulsation is normal
What aspects of cysts would make them less likely to show posterior acoustic enhancment?
Small cysts (<5mm)
Deep cysts (>3cm)
what determines acoustic impedance in a tissue?
Sound velocity in and density of tissue
defined as the product of the density (in kg/m^3) and speed of sound (in m/s) in the tissue
4 yo girl with fever and flank pain
Pyelonephritis
edematous kidney with decreased flow esp at the poles
(DMSA scanning is the classic test used to diagnose pyelonephritis)
imaging usually only done if not responding to tx and concern for complication
in the groin
pseudoaneurysm
arising from the common femoral artery, with the classic “yin-yang” sign within. This “yin-yang” appearance indicates that there is bidirectional flow due to swirling of blood within the pseudoaneurysm.
Distance-measurement calipers are seen on the neck of the pseudoaneurysm.
An arteriovenous fistula will have forward flow, not to-and-fro flow, at the site of the fistula
38F diabetic
Focal Fatty infiltration
echogenicity, elongated configuration, lack of mass effect, and a characteristic location (posterior aspect of medial segment) are characteristic features of steatosis at ultrasound
Ddx:
Hepatic cavernous hemangioma; also echogenic, but typically round and exert mass effect. Chemical shift MR can help distinguish between this entity and focal fat in problematic cases
Hepatocellular carcinomas may be echogenic (and may mimic hemangiomas), but the normal appearance of background liver, the lack of mass effect, and the linear border seen here argue against it
Hepatic adenomas may be slightly echogenic, but they also exert mass effect and are typically round
What is the artifact and what causes it
Reverberation artifact
caused by back and forth reflection of US beam by two closely spaced interfaces
echoes appear as multiple equally spaced lines
often caused by highly reflective interfaces such as calcification or metallic objects
