What makes the EYE a great way to measure blood glucose?
Updated: Nov 22, 2021
Measuring blood glucose levels is an essential daily routine for most of the millions of people who live with diabetes. The well-known finger-stick test is one of the most common methods used to sample blood glucose. The drawback to finger-stick tests is that they require a sample of blood that can only be obtained by piercing the skin. They are, therefore, amongst other things, invasive and can be painful. Whilst the devices used to perform finger prick testing have improved over the years they have been in use; the core technology remains the same.
At Occuity, we believe that a simple, pain-free scan of the eye will soon be able to provide a better solution.
Connected to the brain via the optic nerve, most people assume that the eye is simply used for seeing the world around us. But in truth, it is so much more. Whilst we are all aware of the need to visit an optician annually to have the health and performance of our eyes checked, we are less aware that during that procedure the eye can also be used as a window on the health of the body. Similarly, at Occuity we are using the power of the eye to provide a better solution for glucose monitoring.
There are many things that make the eye a wonderful solution to measuring blood glucose.
Firstly, the eye is the only part of the body that is transparent. It, therefore, presents a metaphorical "window" that we can use to "see" inside the body without the need to actually touch the body at all.
The eye also represents a relatively stable organ to analyse as it doesn’t change particularly rapidly over time. Many companies have sought to tackle the challenge of non-invasive glucose testing by looking at the skin for an answer. There are many drawbacks to using the skin as it can vary a lot and vary in a short space of time. Aspects such as temperature, hydration, level of suntan and even the pressure of the meter on the skin can alter the results obtained.
By comparison, the eye represents a very stable medium to measure and test. It does not change much over time. Indeed, if you need glasses you don’t need to change them every week or month; it is a much more gradual variation.
A key characteristic of the eye is that the aqueous humour is very similar to blood plasma. In fact, the aqueous humour is effectively an ultra-filtrate of blood i.e. blood with the red and white cells taken out. This important fact means that the levels of glucose found in the eye correlate very well with those in the blood in our veins. More importantly, we have been able to demonstrate that the level of glucose in the eye changes rapidly in line with changes in the blood glucose level:
Last but not least, many chronic diseases, including diabetes and Alzheimer’s Disease, leave markers in the eye that can be used to determine whether a person has that particular condition. This allows us to monitor the status of the disease and is a crucial factor in our development of a glucose screening device which, in the UK for example, we hope will enable us to help identify “the missing million”. These are people who have diabetes, but don’t know it and are therefore at risk of the many side effects going untreated.