--%>

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 : 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 : Define antigensity Define antigensity?

    Define antigensity? Answer: The capability of an antigen to join particularly with the final products of immune response is termed as antigensity.   <

  • Q : Gliding joint What do you mean by

    What do you mean by Gliding joint?

  • Q : Preventive measures for Influenza What

    What preventive measures must be taken for Influenza?

  • Q : Regarding thickness of walls how

    Regarding the thickness of their walls how dissimilar are the heart chambers?

  • Q : Elucidate the word polyembryony

    Elucidate the word polyembryony?

  • Q : Define Diplomatic Protocol Diplomatic

    Diplomatic Protocol: The task of diplomacy is to pursue, promote and sustain international relations, to remove and settle misunderstandings and troubles that have arisen in relations among subjects of international law and international relations in

  • Q : Describe peristaltic movements Describe

    Describe peristaltic movements? Describe their role in the human digestion?

  • Q : Views of Conflict - Organizational

    1)     Traditional view: the early approach to conflict assumed that all conflict was bad. Conflict was viewed negatively, and it was used synonymously with such terms as violence, destruction, and irrationality to reinforce its negative connotation. Conflict,

  • Q : Scheduling for Effective Resource

    Scheduling for Effective Resource Utilisation:A) It is invariably ineffective to always start activities at their ES time: causes peaks and troughs in resource usage (people, materials, equipment and working capital).