BREAST LESION LOCALIZATION - A FREEHAND, INTERACTIVE MR IMAGING-GUIDED TECHNIQUE

PURPOSE: To evaluate interactive magnetic resonance (MR) imaging-guide d preoperative needle localization and hookwire placement in the nonco mpressed breast in patients in the prone position. MATERIALS AND METHO DS: Nineteen MR imaging-guided breast lesion localization procedures w ere performed in 17 patients aged 38-70 years (mean age, 48 years) by using an open-platform breast coil in either a 1.5-T, closed-bore imag er (n = 14) or a 0.5-T, open-bore imager (n = 5). Rapid imaging (fast spin-echo, water-selective fast spin-echo, or water-specific three-poi nt Dixon gradient-echo) was alternated with freehand manipulation of a n MR-compatible needle to achieve accurate needle placement. RESULTS: Up to three manipulations of the needle were required during an averag e of 9 minutes to reach the target lesion. MR imaging findings confirm ed the final needle position within 9 mm of the target in all cases. T he accuracy of 10 localizations was independently corroborated either at mammography or at ultrasonography. Nine lesions were visible on MR images only. CONCLUSION: Interactive MR imaging-guided, freehand needl e localization is simple, accurate, and requires no special stereotact ic equipment. Lesions throughout the breast, including those in the an terior part of the breast and those near the chest wall, which can be inaccessible with standard grid or compression-plate techniques, can b e localized. A variety of needle trajectories in addition to the horiz ontal path are possible, including circumareolar approaches and tangen tial needle paths designed to avoid puncture of implants.