Subungual glomus tumors: evaluation with MR imaging.

Abstract

To determine the magnetic resonance (MR) imaging features of subungual glomus tumors. Thirty-one patients with a clinical suspicion of glomus tumor and 10 control subjects underwent MR imaging at 1.5 T. MR images of normal glomus bodies of a cadaver finger were correlated with histologic slices. With a local surface gradient coil, the pixel size reached 117 microns in one direction. Relaxation times were measured. Gadoterate meglumine was injected in 19 patients. Normal glomus bodies were visualized in the reticular dermis of the nail bed. Twenty-seven of 28 pathologically confirmed glomus tumors were detected with MR imaging. A peripheral capsule was present in most tumors. The nail matrix was compressed in 13 cases. The authors were able to differentiate three subtypes of glomus tumors (vascular, solid, and myxoid) on the basis of relaxation times and enhancement characteristics. Four patients had mucoid cysts or angioma in the nail bed. MR imaging can help accurately define the location and limits of glomus tumors before excision.