Interactive MR-guided, 14-gauge core-needle biopsy of enhancing lesions in a breast phantom mode.

RATIONALE AND OBJECTIVES

The authors attempted to determine the accuracy of magnetic resonance (MR) imaging-guided core-needle biopsy performed with a titanium biopsy needle in a breast phantom.

MATERIALS AND METHODS

Eight 6-7-mm lesions were created at random positions in a lard breast phantom. Each 0.2-mL lesion contained 0.118 mg of gadopentetate dimeglumine, 0.0025 mL of methylene blue dye, and 23.8 mg of gelatin. Rapid fast spin-echo MR imaging was used to guide placement of a 14-gauge titanium core-biopsy needle. A 1.5-T MR imager was used with an open-platform phased-array breast coil.

RESULTS

Visualization of blue dye in core specimens confirmed successful biopsy in 16 of 16 attempts. One (n = 13) or two (n = 3) passes through the "skin" of the phantom were necessary for biopsy. The needle trajectory was adjusted less than three times for each pass through the "skin" in 15 of 16 biopsies. Cores that contained lesion material were obtained in the first sample in 15 of 16 biopsies. On T1-weighted images, needles cast 7-mm-diameter artifacts.

CONCLUSION

MR imaging can be used accurately to guide core-needle biopsy of 6-7-mm lesions in a breast phantom.