MRI-guided vacuum-assisted breast biopsy: A phantom and patient evaluation of targeting accuracy

Purpose: To determine the spatial localization errors of magnetic resonance imaging (MRI)-guided core biopsy for breast lesions using the handheld vacuum-assisted core biopsy device in phantoms and patients. Materials and Methods: Biopsies were done using a 10-gauge handheld vacuum-assisted core biopsy system (Vacora, Bard, AZ, USA) on a 1.5T MRI scanner (Philips Achieva, Best, The Netherlands). A standardized biopsy localization protocol was followed by trained operators for multiplanar planning of the biopsy on a separate workstation. Biopsy localization errors were determined as the distance from needle tip to center of the target in three dimensions. Results: Twenty MRI-guided biopsies of phantoms were performed by three different operators. The biopsy target mean size was 6.8 ± 0.6 mm. The overall mean three-dimensional (3D) biopsy targeting error was 4.4 ± 2.9 mm. Thirty-two MRI breast biopsies performed in 22 patients were reviewed. The lesion mean size was 10.5 ± 9.4 mm. The overall mean 3D localization error was 5.7 ± 3.0 mm. No significant differences between phantom and patients biopsy errors were found (P ± 0.5). Conclusion: MRI-guided handheld vacuum-assisted core biopsy device shows good targeting accuracy and should allow localization of lesions to within ∼5 to 6 mm. © 2009 Wiley-Liss, Inc.