Mammography and GYN imaging Flashcards
Dense breat tissue categories
Mammogram anatomy
Mammogram views
Breast cancer screening recommendations
- They vary for general population:
- Most conservative: Start at age 40, image anually
- USPSTF: Start at age 50, image every two years
-
For patients at high risk:
- Start imaging at age 30 with mammogram and breast MRI
BIRADS
When is BIRADS 0 appropriate?
When a screening mammogram (not diagnostic) finds something of uncertain signfiicance
Diagnostic vs screening mammograms
Screening mammograms show only two views of each breast (CC and MLO)
Diagnostic mammograms have multiple views from different angles and better magnification, enabling much better characterization of a lesion. An ultrasound is often additionally indicated following a diagnostic mammogram, and is performed at the same appointment.
Indications for a diagnostic mammogram
- Callback from a screening mammogram (BIRADS 0)
- Palpable mass on exam
- Patients with short interval followup for abnormal mammograms (BIRADS 3)
- Patients with known breast cancer who require further pretreatment or preoperative workup (BIRADS 6)
Utility of dopplar ultrasound in workup of a breast mass
Can tell you if it is cystic (no flow) or solid (bloodflow)
For biopsy-confirmed breast cancer with clinically suspected stage 1 disease . . .
. . . no further imaging is required before surgery (at least for staging purposes)
Indicatons for breast MRI
- High risk screening
- Intermediate risk screening
- New diagnosis of breast cancer – to evaluate for contralateral malignancy not detected on mammography (note, requires contrast)
- Evaluating for breast implant rupture (does not require contrast)
Does MRI ever replace mammography for screening?
NO
It only ever is used in conjunction with mammography
Some low-grade conditions, like DCIS, are more easily identifiable on mammography than MRI
Handling of axillary lymph nodes
The sentinel lymph node will typically be biopsied for breast cancer surgery.
If positive, the patient will return for an axillary lymph node dissection.
When should a patient with a history of thoracic radiation begin mammography screening?
10 years following radiation
Often contrast MRIs are also indicated for these cases
The classic example is radiotherapy for childhood or young adulthood Hodgkin’s lymphoma
When should a patient with family history of breast cancer begin mammography screening?
If their family member was diagnosed before age 50, 10 years prior to their age of diagnosis
Otherwise, standard screening schedule
What is the only situation in which you don’t use contrast on a breast MRI?
If you are evaluating for ruptured breast implants
BRCA1 and BRCA2
Current recommendations regarding screening for ovarian cancer
Nothing has been shown to be effective! This includes clinical exam, transvaginal ultrasound, and CA-125.
There is no good evidence, even for high-risk groups like Lynch syndrome patients, however sometimes these patients are screened anyway.
What is the normal endometrial thickness in a postmenopausal patient?
< 5 mm if not on hormone therapy
< 8 mm if on hormone therapy
You detect endometrial thickening suspicious for endometrial cancer on ultrasound. What are the next steps?
Either straight to biopsy, or sonohysterogram first if you want to be confident there is no polyp or other structure you may miss with a biopsy alone.
Endometrial hyperplasia on sonohysterogram
Retained products of conception on ultrasound
There will be vascular flow
This is a key finding
Once you have your diagnosis from biopsying endometrial cancer, what is the next step?
Pelvic MRI with and without contrast to stage the cancer
Also, CXR to look for pulmonary metastases.
This will determine whether the patients gets TLH-BSO, or chemo/rad.
1 and #2 most common breast masses in a woman under age 30
1: Fibroadenoma
Initial imaging in the workup of infertility
- Pelvic ultrasound
- Hysterosalpingogram (to evaluate uterine and fallopian tube patency)
Limitation of sonohysterogram in comparison to hysterosalpingogram
Sonohysterogram cannot visualize the fallopian tubes well, while hysterosalpingogram can
Shown is a normal HSG with “fill and spill”
Three main treatment options for fallopian tube obstruction
- IVF
- Laporoscopic lysis of adhesions (if present) in attempt to increase fertility
- Interventional radiology (attempt to achieve patency through tubal catheterization)
Routine workup of new pregnancy
- Transvaginal ultrasound at 6 weeks post-LMP (note, NOT transabdominal)
- Serial beta hCG
At what level of beta hCG should you be able to see an intrauterine pregnancy if it is present?
>1000 mIU/mL
Major limitation of transabdominal ultrasound to visualize GYN anatomy
It often requires the bladder to be full, which cannot be done in the acute setting
Management of a patient with suspected ectopic pregnancy but negative imaging findings apart from no visible intrauterine pregnancy (with beta hCG < 1500)
- Given the beta hCG, this may yet be an intrauterine pregnancy that is still too small to visualize
- In this situation, there should be serial beta hCG and clinical monitoring
- If date of LMP is in question, US should be repeated in 7-10 days
Management of a patient with suspected ectopic pregnancy but negative imaging findings apart from no visible intrauterine pregnancy (with beta hCG > 1500)
- D&C followed by progression to laporoscopy or methotrexate if not present
- Straight to methotrexate
- Straight to laporoscopy (preferred if pain is severe or there are signs of blood loss)
Time by OB ultrasound findings
What is going on in this pregnant woman’s transvaginal ultrasound?
There is a gestational sac with an associated yolk sac and fetal pole
This gestation is 6 weeks along and should also have an observable heartbeat. By the time it is 5 mm long, its heartbeat should be > 100 bpm.
Criteria for methotrexate in suspected ectopic pregnancy
Additionally, no evidence of ruptured ectopic
What gives you the most accurate EDD for a pregnancy?
The first trimester ultrasound crown-rump length
How does a normal fetal Down syndrome screening ultrasound result change the risk of Down syndrome?
It reduces it by half
So by no means does it exclude Down syndrome
Three major markers of Down’s syndrome on fetal ultrasound
- Increased nuchal fold thickness (> 6 mm)
- Major structural abnormality (heart abnormality, omphalocele, etc)
- Shortened or absent nasal bone
There are lots of indications for repeat fetal ultrasound in the 2nd or 3rd trimesters
What are some inappropriate ones?
Parental desire to see
Fetal determination of sex unless medically necessary for some reason
Even in high risk pregnancies, fetal weight should not be checked more frequently than. . .
. . . every 2-3 weeks
What is the best way to estimate fetal weight in the 2nd and 3rd trimesters?
Abdominal circumference
This reflects fetal glycogen stores and is a sensitive marker for placental insufficiency
Diagnosing appendicitis in pregnancy
1st line: Ultrasound
If negative: non-contrast MRI (Gadollinium should not be used in pregnant patients)
While MRI is fine in pregnancy, you should NOT. . .
. . . do a contrast MRI
Gadollinium contrast may be fetotoxic
