Preoperative Needle/Wire (or Seed) Localization

Indications

• Preoperative localization of a nonpalpable, image-detected lesion or biopsy marker clip prior to surgical excision
• Guide excision of a malignancy, high-risk lesion (e.g., ADH), or discordant/uncertain finding
• Bracketing of an extensive area of disease for surgical planning

Patient prep

• Coordinate timing with operating room (wire localization is same-day as surgery)
• Review anticoagulation; informed consent
• Imaging modality chosen to match lesion visibility (mammographic/stereo, US, or MRI guidance)

Contrast

Technique

• Localize target under mammographic/stereotactic, ultrasound, or (rarely) MRI guidance
• Advance localizing needle to lesion; deploy hookwire, or place non-wire localizer (radioactive seed / RFID / magnetic / radar reflector)
• Obtain orthogonal post-placement mammograms (CC and ML) documenting device position relative to the lesion/clip
• Provide images and report to surgeon describing depth and relationship to lesion; specimen radiograph confirms target excised

Series / Sequences

Key points

• Specimen radiograph is mandatory to confirm the targeted lesion/marker and the localizing device are within the excised tissue
• Wire-free localizers (radioactive seed, RFID, magnetic seed, radar reflector) allow decoupling localization from surgery scheduling
• Bracketing with two wires/seeds delineates margins of large/extensive lesions
• Communicate clearly with surgeon regarding entry site, depth, and lesion-to-device relationship

References