Predictors of progression in glaucoma - ‘POP study’
Research type
Research Study
Full title
A longitudinal observational study of patients whose glaucoma treatment is initially successful and people with no glaucoma to explore whether the water drinking test, day phasing, or aqueous dynamics data (outflow facility) best predicts progression of glaucoma two years later.
IRAS ID
351334
Contact name
K Sheng Lim
Contact email
Sponsor organisation
Guy's and St Thomas' NHS Foundation Trust
Duration of Study in the UK
4 years, 0 months, 1 days
Research summary
In glaucoma the pressure in the eye is too high. Left untreated this can cause gradual vision loss. We want to know if tests we can do now might predict whether someone’s glaucoma will get worse over time. This could help us choose the best treatment. Usually we only do surgery if medication is not controlling a patient’s glaucoma, but patients at more risk of worsening could have surgery earlier.
We usually take one eye pressure measurement at the clinic. Other tests take more time but may give more information. Firstly, phasing is taking measurements every two hours over the day is more sensitive as the pressure varies, but the patient has to stay at the clinic all day and staff have to repeat tests when they could be treating other patients. A second quicker test involves measuring the eye pressure then asking the patient to drink a litre of water. This causes the pressure to go up. How much it goes up tells us how well the pressure in the eye is being controlled. A third test measures how fluid flows through and out of the eye. These tests have been used for years. They are not new or experimental.
We will ask glaucoma patients who join the study to come to the clinic to have these three tests. Two years later we will review their medical records to see if their glaucoma has worsened. This way we can see whether any of the tests we do now (including the usual one-off pressure check) can identify patients whose glaucoma progress. We will also compare the tests to see which is the most sensitive measure of how well the eye pressure is being controlled. For comparison we will do the tests on a group of people who do not have glaucoma.
REC name
Wales REC 6
REC reference
25/WA/0347
Date of REC Opinion
27 Nov 2025
REC opinion
Favourable Opinion