Medicare payment for part of Ga PSMA PET/CT scan?

I recently enrolled in a clinical study evaluating a Gallium tracer in a PET/CT scan. I knew in advance that Medicare would not cover the cost of the scan nor the cost of the Gallium compound, both of which I have agreed to pay. The clinical trial cost was not free. But I plan to appeal to Medicare regardless in the hope that perhaps they would pay for the PET/CT scan portion (not the Gallium which is not an approved drug). Has anyone had any success in doing this?

I am thinking the scan itself is an approved diagnostic approach so perhaps this is possible. If you were successful, I would like to know the approach you took (eg letter from doctor, rationale for why the scan was medically necessary etc). In my case recurrent prostate cancer and I have had prior (free) psma scan and axumin scan.

Thanks in advance

Howard,
Yes I had axumin and that is Medicare approved.
Teddy