Advice re diagnostic methods for GCA

[Fatsiajaponica]

I have a history of eye issues since being diagnosed with PMR in May last year. Uveitis and detached retina post covid, cured with 60 mgs of pred and now all better. Both eyes now diagnosed with steroid induced glaucoma, now down to 12.5mgs pred. I have been on a steady and careful reduction but have now been diagnosed with micro aneurysms in the other eye. My research has found that GCA can be the culprit when teamed with nasal, left sided face pain( which I have had consistently and put down to sinus issues.) Apparently this all could be related to carotid artery GCA issues.

I am being treated by Moorfields eye hospital and have x 2 appointments in the next 2 weeks. I have questioned them previously re GCA, asking what are the signs to them that it is not GCA in the past. This time I am thinking I need to ask for further investigation so the question is what to request? PET/CT scan? Is this not possible whilst on 12.5 mgs of pred? Biopsy which isn't always helpful? I am due to reduce to 11 mgs next week but reluctant whilst this is going on.

Many Thanks