Pars planitis (peripheral uveitis) is a disease of the eye in which there is inflammation of the pars plana, a small area of tissue next to the iris that is responsible for making aqueous humor (the fluid in the eye that nourishes the lens and cornea). Pars planitis is often referred to as intermediate uveitis because the pars plana is a part of the uvea. This condition most often affects young men and is generally not associated with any other disease or symptoms (idiopathic). However, there have been a few case reports of an association with autoimmune disease such as Crohn’s disease. Some experts also suggest a possible association with multiple sclerosis, sarcoidosis, cat scratch or Lyme disease.