Pacinian corpuscles: an explanation for subcutaneous palmar nodules routinely encountered on MR examinations.

Pacinian corpuscles, the main touch receptors to pressure and vibration, are ubiquitous in the deep dermis and hypodermis of the fingers and palms. Nevertheless, their existence is largely unknown to most radiologists. We frequently noted hyperintense nodules in the palms of patients on water-sensitive MRI sequences, but were unable to explain their etiology. We recently encountered two patients who had Pacinian corpuscles identified at surgical exploration and pathological analysis. Pre-operative MRI examinations in these patients showed T2 hyperintense subcutaneous palmar nodules corresponding to these corpuscles in a pattern identical to those seen incidentally in other patients. Descriptions from the dermatopathological and orthopedic literature closely correspond to our MRI observations. Based on these data, we hypothesize that the MRI finding that we previously noted represents normal Pacinian corpuscles.