Magic Angle - Video Lesson

Hey everybody, and welcome back to our course on MRI artifacts. In this lesson, we will discuss magic angle, which despite its fun sounding name, actually has the power to cause normal structures to appear pathologic. We will discuss what this phenomenon looks like, what causes it, and how to troubleshoot it to avoid magic angle artifacts. Let's get started. First, let's talk about what the magic angle artifact is. The magic angle artifact refers to an artificial increase in signal intensity that occurs in collagen rich tissues when those tissues are oriented at approximately relative to the main magnetic field B0. Under normal circumstances, structures such as tendons and ligaments appear dark on MRI due to their very short T2 relaxation times. When the magic angle condition is met, however, these same structures may appear unexpectedly bright particularly on short echo time sequences such as T1 weighted, proton density, and gradient echo images. This