Future reference. Eyes are Eyes being either human or avian. My husband who is a retired eye doctor has told me that when in the eye, you want to smother the lice. You can use either as mentioned, antibiotic ointment or Vaseline. Treat one eye at a time so the bird can see to eat. Clean the treated eye well before you treat the other eye. You may have to retreat if the lice jump between eyes.
Sorry to hear that you have to deal with Marek's disease.

You aren't alone. You may want to read my article about my experiences dealing with the disease when I discovered I had it in my flock. I hope it helps you out a bit.
https://www.backyardchickens.com/ar...-i-learned-to-deal-with-mareks-disease.76944/