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 approximately 5 to 6 mm.