Posttraumatic Subepineural Hematoma of the Median Nerve Diagnosed With Ultrasound Imaging.

This case report demonstrates the utility of ultrasound (US) in the diagnosis, characterization, and follow-up of an intraneural median nerve hematoma following peripherally inserted central catheter (PICC) placement. A patient presenting with neuropathy in the median nerve distribution was evaluated in the US clinic. US successfully identified an intraneural hematoma of the median nerve, characterized it as subepineural, and detected its incomplete resolution during follow-up imaging. This case highlights the value of the US as a first-line modality for the evaluation of median nerve hematoma in patients exhibiting neuropathy following PICC placement. On US, a subepineural intraneural hematoma will cause eccentric displacement of and mass effect on nerve fascicles, with both the hematoma and fascicles encased within the epineurium.