MR mammography: influence of menstrual cycle on the dynamic contrast enhancement of fibrocystic disease

Magnetic resonance mammography (MRM) provides data regarding the nature of tumours based on contrast medium dynamics; fibrocystic changes in the breas t, however may lead to false-positive results. This study investigated whet her the contrast medium dynamics of fibrocystic changes are dependent on th e menstrual cycle. Twenty-four patients with palpable lumps but normal mamm ographies and ultrasound studies were examined. The MRM technique was perfo rmed during the first and second part of the menstrual cycle using a FLASH 3D sequence, both native and at 1, 2, 3 and 8 min af.-ter intravenous appli cation of 0.15 mmol/kg body weight of gadodiamide. The calculated time-inte nsity curves were evaluated based on the following criteria: early percenta ge of contrast medium uptake in relation to the native value formation of a plateau phenomenon after the second minute the point of maximal contrast m edium uptake and calculation of the contrast enhancing index. During the se cond half of the menstrual cycle, a generally greater contrast medium uptak e was observed. Nevertheless, when further diagnostic criteria, such as con tinuous contrast medium increase as a function of time, were considered, th ere was no increased rate of false-positive findings. The phase of the mens trual cycle may affect the specificity of the examination, if only the quan titative contrast medium uptake and the percentage of contrast medium uptak e in the first 2 min are considered. A control MRM during the other half of the cycle may then be indicated and additional diagnostic criteria may imp rove specificity.