Figure 1.

Representative photographs depicting upper (a) and lower (b) eyelids of various grades in pterygium patients. (a0, b0) Grade 0, no loss of meibomian glands; (a1, b1) Grade 1, meibomian gland area loss less than one-third; (a2, b2) Grade 2, meibomian gland area loss was greater than one-third and less than two-thirds; (a3, b3) Grade 3, meibomian gland area loss was greater than two-thirds