Imaging modalities

Question 1

limitations of 2D mammo

Answer 1

-summation artifact/superimposed tissue
-malignancies can be hidden in glandular structure
-false positive/false negative

Question 2

Digital breast tomosynthesis (DBT)

Answer 2

-images are perpendicular to beam
-images are parallel to detector (stacked)
-projections are reconstructed into slices
-slices are dependent on breast thickness

Question 3

sweep of gantry (Arc)

Answer 3

-set by vendor
-hologic and fuji: 15 degree sweep (standard mode)
-GE: 25 degree sweep
-siemens: 50 degree sweep

Question 4

projections

Answer 4

-angles in degrees from the negative to positive side
-these are the images initially taken
-this is where the actual radiation dose to the pt comes from

Question 5

slices

Answer 5

-number of images created from projections to create the 3D mammo
-dependent on how much the breast is compressed in millimeters
-slices created from projections
-1 mm thick slices

Question 6

for CC DBT image set taken from

Answer 6

inferior to superior breast (breast side closest to detector)

Question 7

for MLO DBT image set taken from

Answer 7

lateral to medial breast (breast side closest to detector)

Question 8

DBT radiation dose

Answer 8

-each projection is a small fraction of the total dose
-DBT: 1.81 mGy one view
-MQSA: 3 mGy per view

Question 9

synthesized view (2D synthetic)

Answer 9

-must have an approved form of 2D images to be read with 3D images
-uses only 3D slices to create synthetic 2D images
-no added dose to pt, cut down dose in half, better visual of details

Question 10

2D synthetic view

Answer 10

-images must include a mark to alert users that images are not FFDM images
-hologic: C-view/intelligent 2D
-GE: V-preview
-siemens: insight 2D
-fuji: S-view

Question 11

what are the indications for breast ultrasound?

Answer 11

-screening breast US
-abnormal mammo
-diagnostic exams (callbacks)
-clinical symptoms: palpable, pain, breast changes
-guidance for intervention
-second look after MRI

Question 12

how does glandular dense tissue appear on mammogram and ultrasound?

Answer 12

appears brighter (white)

Question 13

Whole breast ultrasound (WBUS) / Automated whole-breast ultrasound (ABUS)

Answer 13

-adjunct screening exam (for asymptomatic and dense breast tissue)
-automatically scans woman’s breast capturing multiple images
-displays them in 3D for radiologist review
-not operator dependent

Question 14

Malignancies on MRI

Answer 14

-use gadolinium as contrast
-malignancies can have hypervascularity and enhance
-it can also cause benign vascular lesions to enhance (lymph node)

Question 15

breast MRI indications

Answer 15

-new cancer staging
-implants
-nipple discharge
-eval of scarring
-problem solving post surgery
-monitoring of neoadjuvant chemotherapy
-searching for primary tumor
-searching for high risk pt

Question 16

breast MRI pitfalls & precautions

Answer 16

-only effective in 50% of pts w/ DCIS but very effective in pt with dense breasts and implants
-high sensitivity, low specificity
-US re-eval. necessary

Question 17

What is the lymphatic system?

Answer 17

network of lymph nodes to rid the body of toxins, waste, and other unwanted material

Question 18

what does the lymphatic system do?

Answer 18

continually collect excess interstitial fluid and drain it away from the tissue

Question 19

what happens without the lymphatic system?

Answer 19

-lymphedema: tissue swelling from an accumulation of fluid that is unable to drain through the lymph system

Question 20

sentinel node mapping

Answer 20

-check for breast cancer cells spreading (metastasizing)
-the first lymph node that drains lymph from specific area of body (usually axillary chain)
-reduce the number of lymph nodes needing to be removed (axillary dissection; removal of Level 1 & 2 nodes)

Question 21

sentinel node procedure

Answer 21

-radioactive isotopes and/or blue dye is injected at the site of the lesion (2 hrs before surgery)
-gamma detector (in surgery) is used to locate path of drainage from the tumor to the sentinel lymph nodes (1-5 sentinel nodes possible)
-can be testing immediately or after procedure (if neg, no need to remove more. if pos, may need to remove more nodes, which causes lymphadenopathy)