BI-RADS US: Microcalcifications situated in fat or fibroglandular tissue are less conspicuous than when calcifications are present in a mass. Small echogenic flecks grouped in tissue may sometimes be identified because they have patterns different from those of acoustic speckle or transversely sectioned Cooper's ligaments. Because they occupy too small a portion of the acoustic beam, microcalcifcations will not shadow. If calcifications are numerous enough for a pattern to be discerned, they may be perceived as scattered or grouped in the area of tissue being examined with ultrasound.