National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Pars planitis


Other Names:
Intermediate uveitis; Peripheral retinal inflammation; Vitritis
Pars planitis is a disease of the eye that is characterized by inflammation of the narrowed area (pars plana) between the colored part of the eye (iris) and the choroid. This may lead to blurred vision; dark, floating spots in the vision; and progressive vision loss. As the condition advances, cataracts, retinal detachment, or macular edema (fluid within the retina) may develop. Pars planitis most often affects young men and is generally not associated with any other disease or symptoms (idiopathic); however, it can be associated with other autoimmune conditions such as multiple sclerosis and sarcoidosis. Treatment typically includes corticosteroid drugs, immunosuppressive medications, and/or surgery.[1][2][3]
Last updated: 6/23/2015
Pars planitis is characterized by inflammation of the narrowed area (pars plana) between the colored part of the eye (iris) and the choroid. This may lead to blurred vision; dark, floating spots in the vision; and progressive vision loss.[1][2] Approximately 80% of cases are bilateral (affecting both eyes), although one eye is typically more affected than the other. As the condition advances, cataracts, retinal detachment, or macular edema (fluid within the retina) may develop.[3]
Last updated: 6/22/2015
The exact underlying cause of pars planitis is unknown. Scientists suspect that it is an autoimmune condition in which the body's immune system mistakenly attacks healthy tissues (certain parts of the eyes, in this case). This is further supported by the fact that pars planitis is sometimes associated with other autoimmune conditions such as multiple sclerosis and sarcoidosis.[2][1]

Although most cases occur sporadically in people with no family history of the condition, pars planitis can rarely affect more than one family member. In these cases, there may be a genetic component; however, a disease-causing gene and specific inheritance pattern have not been identified.[4]
Last updated: 6/22/2015
Pars planitis is typically diagnosed based on a specialized eye examination. During the exam, the ophthalmologist will typically see clusters of white blood cells trapped within the eyeball that are called snowballs (or "inflammatory exudate"). If these clusters are located on the pars plana, they are known as snowbanks. Snowbanks are considered a "hallmark" sign of pars planitis.[1][2]

It is often recommended that people over age 25 with pars planitis have an MRI of their brain and spine to rule out multiple sclerosis.[5]
Last updated: 6/23/2015
The first approach to treating pars planitis is corticosteroid eye drops or injections near the eye to control inflammation. Non-steroidal anti-inflammatory drugs (NSAIDs, including aspirin) or steroid medications (such as prednisone) can be taken by mouth. If these strategies are not successful, other medications may be given to reduce the body's immune response (medications called immunosuppressants, such as methotrexate).[2][3] 

If medications are not effective, surgery may be considered. Cryotherapy has been performed in affected people to remove eye tissue that has inflammation. Although this surgery has been shown to be effective in restoring clarity of vision, there are concerns that it may cause damage to other parts of the eye. Another surgery, known as vitrectomy, can be done to remove cloudy fluid (vitreous humor) from the eye.[6][2]
Last updated: 6/23/2015

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.

  • Adalimumab (Brand name: Humira) - Manufactured by AbbVie Inc.
    FDA-approved indication: September 2018, adalimumab (Humira) received expanded approval for the treatment of non-infectious intermediate, posterior, and panuveitis to include pediatric patients 2 years of age and older. It was approved for use in adults with non-infectious intermediate, posterior, and panuveitis in June 2016.
    National Library of Medicine Drug Information Portal
    Medline Plus Health Information

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Pars planitis. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Organizations Providing General Support

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Financial Resources

  • Patient Access Network Foundation (PAN Foundation) has Assistance Programs for those with health insurance who reside in the United States. The disease fund status can change over time, so you may need to check back if funds are not currently available. 

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.
  • The American Academy of Ophthalmology provides information about pars planitis. Click on the link to view the information related to this topic.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Pars planitis. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

  • Once an individual with pars planitis loses vision, can they get it back?  And what are the different surgeries that can treat pars planitis? See answer


  1. Pars Planitis. NORD. 2008; http://rarediseases.org/rare-diseases/pars-planitis/.
  2. Robert H Janigian, Jr, MD. Intermediate Uveitis. Medscape Reference. August 2013; http://emedicine.medscape.com/article/1208794-overview.
  3. Michael Tolentino, MD; Reza Dana, MD, MPH, MSc. Retinal vasculitis associated with primary ocular disorders. UpToDate. November 2014; Accessed 6/22/2015.
  4. PARS PLANITIS. OMIM. 2001; http://www.omim.org/entry/606177.
  5. Uveitis. MedlinePlus. September 2014; http://www.nlm.nih.gov/medlineplus/ency/article/001005.htm.
  6. Prieto JF, Dios E, Gutierrez JM, Mayo A, Calonge M, Herreras JM. Pars planitis: epidemiology, treatment, and association with multiple sclerosis. Ocular immunology and inflammation. 2001; 9:93-102. http://www.ncbi.nlm.nih.gov/pubmed/11449325. Accessed 4/3/2012.