Sometimes after surgery, tiny little cysts occur at the sites where sutures were used. "Unroofing" the milia simply means to decapitate, or cut off the top of the cyst so that the contents can come out and no longer form a cyst. Hope this explanation helps.
The term “unroofed” means that the superficial area of skin is opened which essentially eliminates the roof over the “milia” after eye surgery and allows the expression of the white material.