--%>

Description of presbyopia and astigmatism

Give a brief description of presbyopia and astigmatism?

E

Expert

Verified

Presbyopia is visual impairment in which there is loss of cililary muscle strength thus reducing the ability of crystalline lens to adjust images of near objects on retina. In presbyopia the near point of vision becomes more distant. The disease generally takes place in old people.

Astigmatism is caused by the irregular shape of refractive structures, mainly cornea. In astigmatism a single object-point might create more than one image on retina and so the vision becomes distorted.

   Related Questions in Biology

  • Q : Actions of antibodies against bacteria

    Explain about the different actions of antibodies against the bacteria and against virus? Why the cellular immune response is activated in case of the chronic viral infection?

  • Q : Taenia solium and Taenia saginata

    Concerning their respective intermediate hosts how different are Taenia solium and Taenia saginata?

  • Q : Hydrophobic interactions in

    Elucidate in concise about hydrophobic interactions in the antigen-antibody interaction.

  • Q : Approaches of Knowledge Management -

    Knowledge management as acquiring and storing information: treating knowledge as a tangible asset, this approach to KM mainly employs technology, specifically information technology, to acquire and store information to be drawn upon by management decision makers and o

  • Q : Peripheral nervous system What do you

    What do you mean by peripheral nervous system (or PNS)? Answer: Peripheral nervous system comprehends the ganglia and nerves of the body.

  • Q : Backlash - Barriers to Diversity -

    Negative reaction to the gaining of power and influence by members of previously underrepresented groups, leading to fear, resentment, and reverse discrimination.  

  • Q : State American Disabilities Act or ADA

    American Disabilities Act (ADA): The legislation passed in the year 1990 which prohibits discrimination against people with disabilities. Below this Act, discrimination against a disabled person is unlawful in transportation, employment, public accomm

  • Q : Kind of immunoglobulin level Which kind

    Which kind of immunoglobulin level will rise whenever an individual is depicted to a parasite? Answer: Serum IgE levels will raise and remain till the parasite is wa

  • Q : Categorization of acquired immunity

    Into how many kinds acquired immunity is categorized. Name them.

  • Q : Osseous and the cartilaginous tissue

    List out the type of tissue which are osseous and the cartilaginous tissue?