Refraction Artifacts and Slice Thickness - Video Lesson

Hey everybody. Welcome back to our course on ultrasound artifacts. In this lesson, we will be discussing two common artifacts found in sonography, refraction and slice thickness. Let's get started. First, let's discuss refraction. Refraction occurs when an ultrasound wave crosses an interface between two tissues with different propagation speeds at an oblique angle. This change in direction, often described as a bend in the sound wave, is governed by Snell's law and results from differences in sound velocity between two media. Snell's law states that the angle of refraction of a wave passing through the boundary between two media is determined by the ratio of their propagation speeds. When the second medium has a higher propagation speed, the wave bends away from the normal. When it has a lower speed, the wave bends toward the normal. When we refer to the normal, what we mean is that