MUC5AC and Keratoconjunctivitis sicca: Dry eye symptoms may be newly developed after LASIK [42], and the loss of corneal innervation caused by flap making has been suggested as the major cause, affecting the corneal-lacrimal gland, corneal-blinking, and blinking meibomian gland reflexes, resulting in decreased aqueous and lipid tear secretion and mucin expression.