Tumoral calcinosis: sonographic sedimentation sign

We present the sonographic findings of tumoral calcinosis in two patients compared with conventional radiography, CT, and MRI. Sonography in both patients demonstrated fluid-sedimentation levels, with more echogenic debris layering dependently. This appearance has been referred to as the "sedimentation sign" on conventional radiography and results from dependent layering of hydroxyapatite crystals within cystic spaces of the lesion. There are only three reported cases in the world literature of sonographic findings in patients with tumoral calcinosis. We describe the first two cases of sonography demonstrating the "sedimentation sign," which may aid in the diagnosis of tumoral calcinosis.