I've had dry eyes for many years prior to PMR. I have taken flaxseed oil for many years, which seems to help me. Here is what NIH concluded for the dry eyes in Sjögren's syndrome:
"Conclusions: Therapy with oral flaxseed oil capsules 1 or 2 g/day reduces ocular surface inflammation and ameliorates the symptoms of keratoconjunctivitis sicca in Sjögren's syndrome patients. Long-term studies are needed to confirm the role of this therapy for keratoconjunctivitis sicca in Sjögren's syndrome."
https://pubmed.ncbi.nlm.nih.gov/17906762/
Note: I currently take 1000 mg. of flaxseed oil (contains ALA omega 3's) and 715 mg. of Omega 3 from Nordic Naturals Algae omega (EPA and DHA omega 3's). You can also get DHA and EPA omega 3's from fish oil, but you risk mercury contamination. Fish get their omega 3's from eating algae. The Standard American Diet (SAD) is very low in omega 3 content due to our ultraprocessed diet.
I also use Systane Ultra drops twice daily and massage my lower and upper eyes immediately after placing the drops. I've tried the other Systane products and they tend to irritate my eyes for some reason. BTW, my optometrist stated that my retinas looked great!