Many of us know that prevention is better than cure – and when it comes to eyesight – this rings truer than ever. Find out how the 4D eye health check at Safarian and Simon Opticians could help you avoid sight loss
We are dedicated to providing clinical care at the highest standard possible and we truly believe our latest investment is the future of eye examinations.
The ‘Spectralis’ by Heidelberg Engineering is a state-of-the-art 4D retinal scanner. This exciting piece of equipment, called Optical Coherence Tomography (OCT), has revolutionised the way we examine the eye. It supplies us with highly detailed images of cross sections through the back of the eye and retina. In other words, we can see ‘in between’ the tissues of the retina – a part of the eye that would otherwise be completely invisible.
Why is that so helpful?
The retina plays a hugely important part in the process of seeing – it ‘captures’ the images we look at and sends them off to the brain, via the optic nerve. If the retina wasn’t working properly, it would stop us seeing clearly (even when wearing glasses).
We can see the retina during a sight test but only the front of it from a head-on view. Well, believe it or not, the retina has eleven layers to it – yes, eleven! Many abnormalities aren’t even visible from the front, so you really can’t confirm an eye is healthy until you’ve seen them all.
Once we have assessed these parts of the eye, we can tell you a huge amount more about your eye health. Diseases of the retina are surprisingly common and many are preventable if early signs are detected. If a problem has already occurred, it’s imperative that it’s treated as soon as possible to maximise the chance of maintaining perfect sight. Remember, there are no pain receptors in the retina, so we wouldn’t feel anything if there were a problem. Even vision loss is easily missed because of the way our brains compensate!
During a standard sight test, a problem can be brought to the optician’s attention because of poor sight or a visible abnormality within the eye, but a 4D retinal scan can show a problem months or even years before it would otherwise become apparent. This means that we can treat it, monitor it, or prevent it from getting worse.
The 4D retinal scanner also has advanced integrated software which assesses the images in even further detail. This can alert you to a retina which for example is dangerously thin but appears otherwise healthy.
‘Glaucoma is often thought to be pressure only related-This is no longer the case, eye pressure measurement is an indicator and should not be referred to as the ‘Glaucoma’ test. Glaucoma is more complex and is due to nerve damage on the retina, which can be pressure related but you can also normal pressure Glaucoma and people who had high pressure but no Glaucoma!’
The OCT is a far more accurate way of assessing nerve changes and due to the high repeatability, there is less chance of missing nerve changes.
Is the Heidelberg Spectralis the same as other OCT scanners?
No. The Spectralis really is the most superior of its kind. But don’t just take our word for it; the same model of OCT scanner used in our practice is also used by NASA to assess the eyes of astronauts whilst in space.
It’s their machine of choice for the same two reasons it is ours:
Reason 1. Its unbeatable Image Quality
It has a higher image quality than other OCT scanners (but that doesn’t mean the pictures just look prettier) it is accurate to 1 micron – that’s one thousandth of a millimetre! Other models of OCT are only accurate to 9 microns. That may still seem small, but that actually means you can’t differentiate all of the layers of tissue and are forced to combine up to 3 layers of tissue into one. If the Heidelberg Spectralis detects a problem, we will know its exact location.
Reason 2. Its Unique Laser Tracking Technology
This allows us to monitor the health of your eyes accurately over time. The laser tracker means that after the first scan is performed, the machine will detect the exact same location time and time again. A little bit like a homing missile (without the blowing up part of course), it recognizes the right part and adjusts accordingly. Without this tracking technology, you will undoubtedly catch a different part in the eye because it would be next to impossible to recreate the same head position accurate to one thousandth of a millimetre. This means we will be confident about any ways the eye is changing. We’ll know if a problem area was getting better or worse, and any uncertainty that it looks different just because we captured a slightly different location will be eliminated.
Who benefits from having OCT?
Absolutely every adult can benefit from having OCT. We can view a part of the eye where it’s likely than no one has seen before. If we know everything looks healthy, it’s great peace of mind and we’ll then have a record of exactly what the back of your eye looks like. We can then make sure that it’s not changing in a way that it shouldn’t be, and should you ever have a concern about your vision or eye health, we can look for anything in the retina that wasn’t there before.
We really do recommend it to anyone, but it becomes even more advisable when you’re over the age of 40, since you’re more at risk of diseases such as glaucoma.
‘If a patient reports with an increase in distortion of vision, we can now confidently tell you if it is Dry or Wet macula degeneration’
Is OCT different to retinal/fundus photography?
Yes! Taking a photo of the back of the eye is commonplace in eye examinations today. Some opticians include it in the price of a sight test or you might have paid a small fee to have it done. If you’re diabetic, you’ll have these photographs taken on a regular basis, most likely at your GP surgery. Whilst this is a useful diagnostic tool, it does not show you any more of the eye than in your standard eye test. It is simply a photograph of what the optometrist can already see. OCT however, shows us all the layers of tissue that sit behind what you can see in a photograph.
‘The normal photo flash typically bleached out subtle pigment changes in macula degeneration, the OCT use Infra-red and no flash’
How long does it take?
The scan is usually very quick and is performed in about 1-2 minutes per eye. We recommend you allow around 20 minutes for the scan though, as this will give us time to discuss the results.
Is it uncomfortable?
No, there’s no discomfort at all. There is no contact with the eye, there aren’t any bright flashes or puffs of air, and you don’t need to have any drops put in your eyes. You can also blink normally whilst having the scan. It simply involves you sitting still and focussing on a small blue cross.
How long do I wait for the results?
The results are instant and we usually discuss them with you during your visit, although there might be the odd occasion where we need to get back to you.
Can I have OCT if I have a cataract?
Yes. In fact, if you have a cataract it’s all the more reason to have OCT. Cataracts form when the lens inside the eye loses transparency or becomes ‘cloudy’. This means it’s more difficult to get a good view of the back of the eye during your sight test. In OCT however, the safe light beam does not get obstructed by the cataract, so we can see the back of the eye clearly.
Is it still advisable to have OCT if I’m diabetic?
Definitely. If you’re diabetic you probably have regular screening appointments where they photograph the back of your eye. This is an important assessment which checks for signs of diabetic retinopathy – or put simply, ‘wear and tear’ caused from the diabetes. But remember, the OCT scan shows us more than the photograph and we can pick up on signs of disease at an earlier stage. The chance of any sight loss is reduced for 9 out of 10 people when diabetic retinopathy is found and treated quickly. Just as importantly, if you’re already at risk of problems in the eye from diabetes, you will undoubtedly want to know about any other factors that could be putting your vision at risk.
‘Diabetic Retinopathy is at its worse when the macula is affected, the OCT will detect the earliest changes to the macula than a normal exam or photo every would do’
We do not have access to the records of diabetic screening appointments so if you have an OCT scan, we will know more about your eyes which means it will give us more information about your eyes, so we can give you the best possible advice and allow us to monitor your eye health and give you the very best advice.
How do I book?
The scan is included with our Private Enchanced Eye Examination, or you can have it added onto our Comprehensive Eye Examination or NHS exam- just ask for OCT or the 4D eye health check.