Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Congenital primary aphakia ?
    ### Response:
    Congenital primary aphakia (CPA) is a rare eye condition that is present at birth in which the lens is missing. In some cases, CPA can be associated with other eye abnormalities including microphthalmia, absence of the iris, anterior segment aplasia, and/or sclerocornea (when the cornea blends with the sclera).
    