What to do if have chalazion damage meibomian glands..?

Use warm compresses: is best! Every time that a meibomian gland is destroyed, it reduces the availability of those left. You want to avoid dry eyes, as those glands help lubricate the tear film. So take preventive care of them. If you have ocular rosacea, treat that to prevent further problems.

Chalazion treatment: Continue to do hot compress on the eye at least twenty minutes twice daily until the swelling subsides.