Nicole my son has had an MRI of the pituitary with and without contrast.  This was because he had high ACTH levels and 17 OHP.  He also had a CT of his adrenals - they do look carefully but it is very rare to find any of these spots as they call them.  Good luck, I am sure it will all go well. Even though high doses of dex did not suppress the 17 OHP, my sons scans came back clear and his levels had been high for over a year!  Is there a chance you could try x4 a day dosing?