Precise MR-guided preoperative marking of breast lesions with an embolization coil

Purpose: To develop and test a new technique for MR-guided localisation of breast lesions. Materials and methods: The examinations were performed on a 1.01 imager in prone position, using a sagittally oriented oval spine coil. The localization device consisted of a perforated lateral plate which can be angulated. The plate contained an "M" shaped tube filled with oil. This enabled exact localization of the lesion in relation to the bore holes on the MR images. After needle placement through a sterile bushing, the 5 mm marking coil was placed through the needle adjacent to the lesion. Then a suspension of charcoal, Cd-DTPA, and water was injected. Suspicious lesions that could be visualised only by MR were localised preoperatively and marked in 6 patients. Results: The lesion size ranged from 0.5 to 3.5 cm (median 1.2 cm). Three benign lesions (intraductal hyperplasia twice, radial scar once) and three malignant lesions (ductal invasive cancer twice, DCIS once) were found. Angulation of the plate was beneficial in three cases. Conclusion: With the new marking technique, exact MR-guided localization of breast lesions using an add-on device is feasible. Construction of an additional MR coil is not necessary. Excision of the lesion is proven by the concomitant excision of the marking coil.