%0 Journal Article %T Resonancia magn¨¦tica mamaria preoperatoria: la gran pol¨¦mica %A Horvath %A Eleonora %A Galleguillos P %A Mar¨ªa C %A Maldonado S %A Paulina %A Fern¨¢ndez G %A Monserrat %A Sa£¿udo G %A Mercedes %A Tiscornia A %A Paula %A Baz¨¢n F %A Juan %A Silva F-A %A Claudio %A Pinochet T %A Miguel A %A G¨¢lvez T %A Joceliyn %A Soza G %A Iv¨¢n %A Uchida S %A Marcela %A Wenzel K %A Heriberto %A Soto N %A Eduardo %A Gonz¨¢lez M %A Paulina %A R¨ªos C %A Chyla %A Dur¨¢n C %A Mar¨ªa Paz %J Revista chilena de radiolog¨ªa %D 2011 %I Scientific Electronic Library Online %R 10.4067/S0717-93082011000400005 %X preoperative examination intended to detect multifocality, multicentricity and bilaterality-once considered the strongest indication of breast magnetic resonance imaging (mri)-is currently being strongly questioned in medical literature. this paper aims at evaluating, based on our experience at cl¨ªnica alemana, santiago, chile, breast mri ability to improve preoperative radiological tumour staging by conventional methods, as well as to determine the proportion of patients in which this diagnostic procedure generated changes in the surgical management. we retrospectively reviewed preoperative mri studies carried out between january 2009 and june 2010. classification: group 1: mri provided no new information. group 2: by detecting additional lesions, mri improved radiological staging without changing the type of surgery planned. group 3: mri showed new benign lesions and caused unnecessary surgery. group 4: mri successfully changed the type of surgery planned based on conventional studies. a total of 419 breast mri scans were performed during a 18-month period; 39% of them were carried out preoperatively. for the analysis, 128 patients were enrolled and distributed in the following categories: group 1 (66%), group 2 (20%), group 3 (2%) and group 4 (12%). in 95.3% of the patients, a single surgery with clear margins was performed. this work demonstrated the usefulness of preoperative mri in our practice, i.e., it allowed for a better radiological staging in one third of the patients and even successfully changed the surgical approach in 12% of cases. %K breast cancer %K breast conserving surgery %K mastectomy %K preoperative breast mri %K radiological staging. %U http://www.scielo.cl/scielo.php?script=sci_abstract&pid=S0717-93082011000400005&lng=en&nrm=iso&tlng=en