Try to upload the image to an image sharing site and then link it. I'd like to see what you're calling the nerve. You describe more of a "wrist block" than a radial nerve block. Proper radial nerve blocks are done at the axillary level, mid-humeral, or elbow.
From Chan's Textbook of Regional Anesthesia:
"The radial nerve passes along the front of the radial side of the forearm. It arises first from the lateral side of the radial artery and beneath the supinator muscle. About 3 inches above the wrist, it leaves the artery, pierces the deep fascia and divides into two branches."
Radial nerve proper (motor and sensory) at the forearm and wrist is a deep nerve on the dorsum of the wrist. There is a superficial (sensory) branch that runs on the radial side and base of thumb. I doubt these can be visualized on ultrasound.