 There's a 61-year-old right-handed female who presents with a left-hand mass that has been present for 15 years, slowly enlarging. There's additional clinical information that you'll receive, including past medical history, past surgical history, her medications, et cetera. You'll also receive information about her overall physical examination and then get to see the actual lesion on visual inspection. The radiograph from this patient shows dense, intense calcification in the palm of the hand. In the center on the axial, short axis, T2-weighted MR, our foci of hypointensity, bulky and mass-like surrounded by high signal intensity, which perhaps is a little more easily seen in the sagittal or lateral projection and also visible in the coronal projection. This surrounding high signal area represents an adventitial bursal reaction to the mass. So what is this mass and what is the differential diagnosis? This will be a subject of intense discussion and review, but here's a few teaching points that come out of the study guide that you may or may not know. This condition occurs in children and young adults. It has a propensity for African-Americans. The primary type is familial in 33 percent of patients. It's associated with CPPD and pseudo-Xanthoma elasticum. The secondary type is associated with abnormalities of calcium, phosphorus, vitamin D, and even renal insufficiency. It has a propensity for the extensor surfaces, even though this one is on the palmar surface. Radiographically, it likes the areas of the hip, the elbow, the shoulder, the foot and the wrist. It's extremely hot on bone scintigraphy, which you'll be shown. It may exhibit a sedimentation sign where calcium sediments in a dependent gravitational milieu. A chicken wire sign, namely septa that are hyper intense representing the interdigitating bursa surrounding and moving within these foci of calcification or osvacation, is typical of this entity in contrast to myositis ossificans, which demonstrates the zonal phenomenon. Calcification or osvacation from the outside end know this lesion ossifies or calcifies from the inside out, a key diagnostic feature on MR and radiographically. These patients may have dental abnormalities. Multifocality is not uncommon. In fact, the average number of lesions per patient is three. This diagnosis is tumoral calcinosis. Stay tuned for more cases and more intense education with multi-modality imaging focusing on MR throughout the musculoskeletal and neural axis.