Second look ultrasound after breast MRI

Patient information factsheet

Why has a "second look" ultrasound been requested?

• A "second look" ultrasound is often done after a breast MRI (Magnetic Resonance Imaging) scan.
• It is used if the MRI shows something unusual, suspicious/unclear.
• This may be something that was not seen, or not clear, on your earlier mammogram or ultrasound.

Reasons why this is done?

1. To match what was found on the MRI with an ultrasound scan

• An MRI is extremely sensitive and can detect very small or subtle issues.
• If the Radiologist finds the same spot on the ultrasound, they can understand it better.
• They can see if it is solid or filled with fluid, and if it looks harmless or needs more checking.

2. To allow easier and faster biopsy

• Most biopsies are easier to do using ultrasound to guide them.
• If the area can be seen on ultrasound, you may not need an MRI-guided biopsy, which:
  • takes longer
  • is less widely available
  • can be less comfortable.

3. To rule out benign (non-harmful) causes that the MRI cannot fully explain.

• MRI scans sometimes show areas that light up, which can turn out to be:
  • benign cysts
  • fibroadenomas (a non-cancerous breast lump)
  • normal glandular (breast) tissue
  • inflammation.
• Ultrasound can often explain this quickly.

4. To check for changes that develop after having an MRI

• If the MRI shows something new or hard to see, the Radiologist will try to check it with an ultrasound scan first.
• This helps them decide what to do next.

5. It helps the Radiologist feel more certain about the diagnosis

• A second look ultrasound helps the Radiologist decide:
  • if the MRI finding is correct
  • if a biopsy is needed
  • or if it's safe to return to routine screening.

Contact our service

Tel.: 020 7288 5888, Monday to Friday 9am to 3pm
Email: whh-tr.ImagingAppointments-WhittHealth@nhs.net