We wrote an introductory piece about this earlier this month and are delighted to now be able to include a short description written by Nacima Kisma a researcher at Moorfields who is helping consultant Mark Westcott with the study. It helps to explain what they hope to achieve from it.
The monitoring of birdshot chorioretinopathy (BCR) cannot be done on a clinical basis only. Clinical signs are usually not immediately detectable when the disease does progress. We therefore need ancillary testing to help us with adjusting and reducing the systemic treatment as quickly as possible.
Electrodiagnosis testing (EDT) is of good value for the monitoring of the disease but does take a long time to perform and is not easy to schedule. Moreover, it can be uncomfortable because of corneal contact lenses, electrodes and flashing lights use.
Visual field testing is much easier to schedule and less uncomfortable than the EDT. The Moorfields Motion Displacement Test (MDT) is a kind of visual field test performed on a laptop. There are 32 lines displayed on a grey background. The lines do move randomly. The patient has to fixate a central spot and to click on the computer mouse when he sees a line moving.
Because it is easy to understand, quick to do (less than 2 minutes) and possible to display on a laptop, we hope that it would be of better use than the other field tests for the monitoring of the disease.
We have decided to look for abnormalities of motion perception in 20 birdshot patients from Moorfields uveitis clinics as a preliminary study. The pilot study is nearing completion and was open to Moorfields patients only.
If this study confirms motion perception losses in BCR, then we postulate that measurement of motion perception losses may be useful in monitoring the disease.
I find this study intriquing as a methodology to measure changes with Birdshot patients. My curiosity is aroused as to whether anyone has tracked whether there is a correlation between Birdshot patients and previous injuries, accidents or disorders that are related to visual perception and movement issues. I sustained a severe whiplash injury, many years ago which left me dizzy for 7 years and impacted on my perception of motion and spacial connectedness to my environment. I have recovered dramatically over a long period of time (17 years), but still have occasional dizzy issues, in addition to the new Birdshot diagnosis.