Magnetic resonance imaging-guided biopsy of the breast: fundamentals and finer points.

Magnetic resonance (MR) imaging is now an accepted component of standard breast-imaging practice. This article reviews the fundamentals of performing an MR imaging-guided biopsy using a grid localization system, and discusses many of the finer points and nuances of the procedure. Tips and tricks found useful at the authors' institution are included, although multiple variations also exist. Performing effective and efficient MR imaging-guided biopsy depends both on deliberate preparation (of the proceduralist, the patient, and the equipment) and on deliberate positioning (of the patient and the sampling device).