[Does breast density have an impact on the indications for MRI?].

MRI indications in breast imaging in breast imaging are now well codified. In diagnostic and screening, MRI in recommended in patients with likely metastatic lymph nodes and in metastasis of unknown cause, and in women with high risk family. In characterisation MRI is recommend in non-calcified subtle findings, non suitable for biopsy. In the staging of a diagnosed breast cancer, MRI has a great impact both for the diagnosis and for the treatment, event if group of women for whom MRI is recommended is still discussed. In follow-up of patients with an history of breast cancer, MRI permits to differentiate recurrence from scarr and to monitor the response to a neo-adjuvant chemotherapy. Dense breast don't constitute a MRI indication by itself, but strengthen recognized MRI indications. Fatty breast easily readable on mammogram don't justify not to perform MRI in the screening of women with high risk family. Conservely in the staging of a breast cancer in an woman or in the monitoring of a neo-adjuvant chemotherapy fatty breast may make US sufficient.