CFR > Title 42 - Public Health > CHAPTER IV—CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES > SUBCHAPTER B—MEDICARE PROGRAM (parts 405 to 426) > PART 406—HOSPITAL INSURANCE ELIGIBILITY AND ENTITLEMENT > SUBPART D—Special Circumstances That Affect Entitlement to Hospital Insurance (§406.50 to §406.52)