Figure 3.

Visualizing the vasa nervorum. Overlay images of ultrasound (US, gray) and two spectral OA components associated with oxygenated (spectrum 1, red) and deoxygenated (spectrum 2, blue) hemoglobin. The single components in the regions outlined with rectangles are shown in three small panels next to the images with the nerve highlighted in yellow. A,B) Two ulnar nerves with intraneural vessels clearly visible in the OA channels. Arteries (presumably the ulnar collateral arteries) and veins at comparable depths can be spectrally distinguished. C,D) Two ulnar nerves with vessels branching into the nerve. E) A median nerve with visible intraneural vessels. F) A radial nerve with two accompanying vessels of medium size, and a small (presumably epineurial) vessel on top.