I am guessing that the procedure will be kind of like this:

What is Ultrasound gel for? | Two Views

The tech will hold a wand (with gel sometimes) over the kidneys and take some pictures. You might be asked to turn to your side or the other side and so forth.

They usually use some gel so the wand moves easily over the skin.
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Often, a second person comes in to look at the pictures of the first person.
Some times they ask a few questions but usually do not provide answers.
Of course, it is still good to ask a few questions if you want.

Later the results are sent to your MD.

M