Most insurances will want you to order CT before PET-CT, and in most cases the PET-CT will require a biopsy proven diagnosis before approval because it is for staging, not for hunting for biopsiable tissue.
The limited PET-CT scans are typically of the heart for cardiac sarcoid or heart failure, and of brain for dementias and seizures.
The scenario most likely to get a PET-CT is if you document concern for a cancer of the cranial nerves which are typically not biopsiable, I agree with Dr. Singman lymphoma would be a good condition to document in the differential.
For cervical lymphadenopathy, CT neck w/ contrast is perfectly adequate.
However, highest yield biopsy for orbital inflammation is likely the orbit. Any imaging (and biopsy) while the patient is on steroids and has quiet disease will have markedly reduced yield.
Best,
Drew
Original Message:
Sent: 11/20/2025 2:21:00 PM
From: Deborah Friedman
Subject: RE: CT PET scan ordering question
The only recent imaging that she had was an MRI of the brain and orbits with contrast which I reviewed and were normal.
Deb
Original Message:
Sent: 11/20/2025 1:58:00 PM
From: Eric Singman
Subject: RE: CT PET scan ordering question
What did mri head neck orbit w/wo show?
Original Message:
Sent: 11/20/2025 1:56:00 PM
From: Deborah Friedman
Subject: CT PET scan ordering question
Hi,
I have patient with periorbital pain, edema and erythema that responded immediately to oral steroids but the manifestations returned when they were tapered and discontinued. I'm concerned about sarcoidosis or IgG4 disease. Her bloodwork was negative but I think she has high cervical lymphadenopathy on exam. Her ENT wouldn't do a biopsy the lymph nodes without further imaging.
I ordered a CT PET scan and have gotten pushback from the facility about the diagnosis code (they are looking for a cancer diagnosis - she doesn't have cancer I think that cancer is unlikely) and what part of the body to image (I basically ordered the whole body).
Should I have gotten other imaging first? I thought about it but thought I should just go for the gold rather than waste a bunch of money. Should the PET scan be more focused? – these disorders can manifest anywhere.
How do you code the order in your workup (with a "C code) when the whole purpose is to find out what the etiology is?
Thank you in advance for your help,
Deb
You can reply privately if you prefer DeborahFriedman@tx.rr.com