Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Adult-onset vitelliform macular dystrophy ?
    ### Response:
    Adult-onset vitelliform macular dystrophy (AVMD) is an eye disorder that can cause progressive vision loss. AVMD affects an area of the retina called the macula, which is responsible for sharp central vision. The condition causes a fatty yellow pigment to accumulate in cells underlying the macula, eventually damaging the cells.
    