Breast MRI interventions
- Remember! 10% of enhancing lesions disappear on day of biopsy; get f/u MRI in 6 months
 MRI Vacuum Assisted Biopsy
- Stylet, introducer with black washer, oburator, 9G biopsy needle, needle guide.
- Don’t need to add any distance to depth b/c needle and cm markings take that into consideration.
- The obturator is in when do images and the tip of it lines up with the center of the collecting chamber of the needle; be within 2 mm of the lesion b/c collecting chamber is large and with suction will get it.
- POST BIOPSY/CLIP MAMMOGRAM IS ESSENTIAL!
 MRI Needle Localization
- Don’t overshoot b/c of the accordion effect when taken out of compression like in stereo where wire or clip will be in a different location from the biopsy site in the Z direction, usually more deep (medial if using a lateral approach & vice-versa) so with NL go only 5 mm beyond lesion; don’t need needle guide (2 cm) for NL so only need to add 5 mm to depth
 Thin Breasts
- Use least amount of compression necessary
- Roll the breast
- Generous skin wheal of anesthetic
- Smaller probe (petite instead of the grande) has a rounded rather than a sharp tip
- Stereo “reverse compression paddle” technique equivalent: 8 channel with grid on both sides.
- Same as above
- Go posterior to lesion and suction anteriorly only
 Superficial Lesions
- Same as above
- Don’t use needle guide b/c want to make sure that the collecting chamber is completely within breast otherwise won’t get suction
- Put needle guide one box below in grid so that you know how far to go in with the black washer
 Medial Lesions
- Oblique positioning with breast in C/L breast opening but only if pt is agile and not large OR 8 channel coil but limited access to posterior tissues b/c of C/L breast and pad so better for anteromedial tissues otherwise go from lateral.
 Posterior Lesions
- Put needle as posterior as possible and suction posteriorly
- Can go behind grid
 Underestimation with 9G MRVAB: same as with stereo literature even though bigger needle
- ADH : DCIS 40% (Stereo 14 G: ADH DCIS/CA 40-50%)
- DCISCA 20%
- DCIS Inv. CA 17%
- Stereo 11 G: ADH DCIS/CA 20%
- Stereo 11 G: DCISCA 10%
- ~3% MSKCC and cancer in 25% of the discordant lesions
- Important when evaluating dis or concordance to review bx images and
- Post bx mammo images and correlate with prebx MR images- did you get it?
- Get post bx MRI in 1 month if not sure-have a low threshold
- MSKCC Breast Cancer Conference 2006