Speckle

Speckle is the characteristic grainy or granular pattern that gives ultrasound images their distinctive textured appearance. It is created by the constructive and destructive interference of ultrasound waves scattered by tiny structures within tissue that are smaller than the wavelength of the ultrasound beam. Speckle is not a direct representation of tissue anatomy — rather, it is an artifact of the imaging process. While speckle can reduce image quality by obscuring fine details, it also carries tissue characterization information that newer techniques exploit. Speckle reduction filters are available on modern ultrasound machines to smooth out the grainy appearance and improve image clarity. Additionally, speckle tracking echocardiography is an advanced technique that analyzes speckle patterns to measure myocardial strain and deformation.