Measuring centimeters from the nipple (CMFN) is the preferred method for describing the distance from the nipple with ultrasound. When scanning, the technologist measures how far the lesion is from the nipple in centimeters. This measurement can be obtained by using a ruler or knowing the width of your transducer face. Some manufacturers have centimeter lines marked on the probe end to better assist in estimating this.

The current trend favors using CMFN measurements over using zones, as the distance from the nipple in centimeters tends to vary less than the distances from the chest wall and breast periphery, especially with changes from compression or patient positioning. Make note that when annotating, CMFN is measured from the nipple and not the areola.

To better understand how to measure CMFN accurately, please refer to the video titled “Measuring CMFN” under Videos, which can be found by hitting the Quiz me button below.