INTERACTIVE MR-GUIDED, 14-GAUGE CORE-NEEDLE BIOPSY OF ENHANCING LESIONS IN A BREAST PHANTOM MODEL

Rationale and Objectives. The authors attempted to determine the accur acy of magnetic resonance (MR) imaging-guided core-needle biopsy perfo rmed with a titanium biopsy needle in a breast phantom. Materials and Methods. Eight 6-7-mm lesions were created at random positions in a la rd breast phantom. Each 0.2-mL lesion contained 0.118 mg of gadopentet ate dimeglumine, 0.0025 mL of methylene blue dye, and 23.8 mg of gelat in. Rapid fast spin-echo MR imaging was used to guide placement of a 1 4-gauge titanium core-biopsy needle. A 1.5-T MR imager was used with a n open-platform phased-array breast coil. Results. Visualization of bl ue dye in core specimens confirmed successful biopsy in 16 of 16 attem pts. One (n = 13) or two (n = 3) passes through the ''skin'' of the ph antom were necessary for biopsy. The needle trajectory was adjusted le ss than three times for each pass through the ''skin'' in 15 of 16 bio psies. Cores that contained lesion material were obtained in the first sample in 15 of 16 biopsies. On Tl-weighted images, needles cast 7-mm diameter artifacts.Conclusion. MR imaging can be used accurately to g uide core-needle biopsy of 6-7-mm lesions in a breast phantom.