The delivery of eye care services has undergone many changes in recent years.  In particular, ophthalmic surgeons now perform major procedures in an ambulatory surgery center (ASC) more often than in a hospital outpatient department (HOPD).  Within the Medicare system, eye surgery ranks in the top three groupings of ASC services; the other two popular services are endoscopy and pain management.  For the future, CMS expects an increase in the number of procedures performed in ASCs.