BUS, through the joint Fight for Sight/BUS Small Grant Awards 2014, is about to support three interesting pieces of research which have just undergone the grant approval process. As you read on, you will see how some of the proposed research builds on earlier research started through the same grants scheme.
THE STUDIES
- Researchers at St Thomas’ Hospital, London, propose to develop and refine the use of the RETeval hand-held electroretinogram (ERG) device.
- Close analysis of patient data is at the heart of the study planned by researchers at Moorfields Eye Hospital, London. They hope to identify factors which could predict good or poor outcomes from birdshot treatments.
- Birmingham-based researchers want to study a laboratory technique called supercell analysis. This type of analysis might be able to distinguish between birdshot and other inflammatory eye diseases, moving a step nearer to creating a diagnostic test for birdshot.
1. RETeval ERG research
Dr Omar Mahroo and Professor Miles Stanford of St Thomas’ Hospital, London, with colleagues at Moorfields Eye Hospital, London and Australian National University, Canberra, want to investigate the potential use of the RETeval device to predict the response to birdshot treatments. They also want to see how readings obtained from RETeval compare with conventional ERG testing.
What is this study about?
Conventional full field ERG testing is not available in all eye units. Testing takes up extra patient and clinic time, especially if it involves patients having to visit another hospital for an ERG. These problems can also mean that ERGs may not be done as frequently as other birdshot monitoring tests. Having a reliable and quick method of performing ERGs in more eye departments would be a useful addition to assessing birdshot. The study aims to see if ERGs recorded with RETeval could be useful in identifying early birdshot uveitis activity. The researchers also want to test the potential use of RETeval ERGs in monitoring or predicting responses to treatment. Additionally, the study will look at whether ERGs could reliably be done with RETeval without the need for dilating the eyes first.
How will the study be done?
The RETeval will be used to measure the photopic 30Hz flicker implicit time. This is altered in birdshot. Study subjects would have their ERGs recorded with RETeval at the start of their clinic visit, before dilating drops have been used, and then recorded again, with dilated eyes, at the end of the clinic visit. This is to see whether or not the ERG results from undilated eyes are as reliable as those obtained from dilated eyes.
A control group of patients from the long-term Twins UK study, based at St Thomas’ Hospital, will be used to provide conventional ERG recordings. Their results will be compared with the RETeval results to see if any correction factors need to be used when comparing results obtained from RETeval with those from conventional ERGs. The control group will also provide genetic information which may help understand the variation in ERG responses in people with and without birdshot.
Results from this research could potentially improve the care of birdshot patients in many eye departments. The study should also provide data to assist in the use of RETeval ERGs in monitoring of new treatments, like the trial of infra-red light in birdshot which is in progress at Moorfields Eye Hospital, and which was part funded by BUS.
2. Factors in birdshot which result in a good outcome
Mr Mark Westcott and colleagues at Moorfields Eye Hospital, London, plan to conduct an in-depth analysis of the records of their group of birdshot patients.
What is this study about?
From their analysis of their birdshot patient records, the researchers aim to get a better understanding of which early features of birdshot might predict a good or less good outcome from treatment. At present, patients diagnosed with birdshot cannot be told about the likely progression of their uveitis because it varies so much between individuals.
How will the study be done?
Using specialised statistical analysis of patient results and tests, the researchers hope to identify factors present at the diagnosis of birdshot which could predict poor or good outcomes at the end of at least five years of observations. The study’s chosen end-points of visual outcome will be those that mean most to patients in their daily lives, such as whether a person retains vision good enough to continue driving.
The researchers will also look for other factors which might influence the course of an individual’s birdshot, eg, genetic markers. This part of the study links with recent findings that at least one other non-HLA-A29 genetic marker is present in some, but not all, birdshot patients.
As well as hoping in the future to be able to provide accurate and useful information at the time of diagnosis and during the management of birdshot, the researchers believe that the findings of their study will enable future randomised controlled trials of birdshot treatments to be better tailored to the patient’s birdshot.
3. Can supercell analysis diagnose birdshot uveitis?
Dr Graham Wallace and colleagues at the University of Birmingham want to answer this intriguing question.
What is this study about?
Currently, there is no diagnostic test for birdshot. This proposed laboratory research study may lead to the development of a diagnostic test. The study’s technique of flow cytometry analysis is based on the concept of blood samples being assessed as ‘supercells’, where each supercell is obtained from 500 randomly-chosen cells. A machine-learning technique can determine the combination of factors that can indicate a disease, and it can then work out how many of these factors are needed to diagnose a disease.
How will the study be done?
The study will make use of 30 of the blood samples donated to the birdshot biobank which BUS helped to fund.
Supercell analysis has already been shown to be capable of distinguishing between patients with eye disease and healthy controls, and also between patients with uveitis caused by Behçet’s disease and uveitis caused by sarcoidosis.
The study will also seek to link the levels of supercells to birdshot disease activity. In addition, the Birmingham researchers, like those involved in the proposed Moorfields study, want to look more closely at the genetic make-up of the birdshot patient samples, following the finding of other non-HLA-A29 genetic markers in some birdshot patients.
Finally…
It is encouraging to see another three lines of birdshot research going forward. Our fundraising for birdshot research really is beginning to make a difference. Results from these types of investigations will slowly but surely improve birdshot diagnosis, its treatments and its outcomes. We would like to thank everyone who has helped raise the funds to help make this birdshot research a reality.