Pars planitis

Uveitis (ocular inflammation) can be present in different parts of the eye. When it affects the inside of the eye, and is located mainly in the peripheral retina and beyond in an area called the pars plana, we refer to this form of ocular inflammation as pars planitis. On examination, we often see “snow banks” (white inflammatory deposits along the pars plana), we also see sometimes abnormal vessels growing along the far retinal periphery, leakage from small retinal vessels, and macular edema.

When diagnosed early, and with appropriate treatment, the course of this form of uveitis is less debilitating than some other forms of uveitis. There is often no known cause, though it is important to rule out infections such as Lyme disease and consider, particularly in young women, the possibility that this is an early manifestation of multiple sclerosis. If a specific cause can be identified, treating the underlying cause leads to a better control of the inflammation than treating only the ocular manifestations.

Pars planitis usually requires medical treatment. However, some patients with severe or long-standing disease, might need a more aggressive intervention such as laser treatment, cryotherapy, or even a vitrectomy.

Symptoms and clinical manifestations

Most patients experience blurred vision and/or floaters and will complain of loss of contrast sensitivity (objects are less well defined and loose their sparkle).

Pain and light sensitivity is rarely present but some patients might perceived a decrease in vision. This is often due to the presence of fluid in the macula area.

What will be done during the eye exam?

An eye exam in uveitis takes time. You should expect on your first visit to stay for one or more hours.

Initially we will review your medical history, so please bring along a good summary of your past medical records or your complete dossier if you have it. Do not forget to bring along any images taken of your eyes in the past. If you wish, these can be sent ahead of time by e-mail, or you can bring them yourself on a CD. Don’t forget also to provide us with the names and dosages of medications, which you have taken in the past (in particular corticosteroids and immunosuppressive agents).

After a complete medical history, your eyes will be examined starting with a careful measurement of your vision, reading vision and possibly contrast sensitivity. After a careful examination of the outside layers of the eye for present and past signs of inflammation, the eyes will be dilated to allow a detailed exam of the inside of your eyes (vitreous and retina).

Other tests are often required in case of ocular inflammation. These include OCT, angiography, autofluorescence among others. The exact type and nature of these ophthalmic exams will be determined and explained to you in detail during your initial visit. Whenever possible, all exams will be completed during this initial visit.

Many uveitis patients also require blood tests, which can be done at a local laboratory. CT scan, MRIs and other radiologic exams are also sometimes required depending of your specific problem and will be discussed with you.

All these tests are necessary to establish a diagnosis, rule out other causes and help determine the best treatment tailored to your needs.


There are several local and systemic drugs available to treat pars planitis. The exact choice depends on the severity of your condition, your response to prior treatment and your specific needs.

Once a treatment plan has been selected, it is important that you follow it carefully and that you tell us how well you are tolerating the treatment or how difficult it is for you to stick to it.

Treating ocular inflammation is a partnership between the patient and the medical team. The more closely we can work together; the better will be the result.

MIOS has an especial interest in ocular inflammation (uveitis). Today we are especially interested in the diagnosis and treatment of patients suffering from this condition. If you wish to be seen or participate in one of our studies, feel free to contact the office or our study coordinator.