Thursday, 29 October 2015

Children's eye health

Testing children can be a fun, exciting and at times frustrating experience. However it is one of the few occasions, other than emergencies, when you can make a real difference to an individuals sight and life. The reason for this is that children under the age of 8 or so (although some papers argue up to 12) are still in the plastic period where they can form new connections in the brain. This means that if a child has poor vision in one or both eyes, correcting it can mean extra connections in the brain and the child having equal vision.

At times the best option is to just prescribe glasses for full time wear . Fully correcting a child's refractive error can often stop a child developing amblyopia (a lazy eye) and can correct some types of squint. If the optometrist is monitoring the child then the child may well be recalled frequently to check their vision and how they are getting on with their glasses.

In other cases the optometrist may have to put drops into the eyes to dilate pupils and allow the eye muscles to relax. These drops do sting (quite a bit) so we suddenly become very unpopular after we have put the first drop in. However it does allow us to get the full prescription and can make all the difference between monitoring in practice with glasses or referring to be treated under the hospital eye service where drops are put in on almost every visit. Children are usually referred to the hospital if the vision stays uneven between the eyes or if there is a turn that they may be able to treat.

However it is not all doom, gloom, horrible patches and stinging eye drops. Correct a child's sight and they will be grateful and at times you can really make a difference to both their future and their now.

I tested a 4 year old whose mother had a lazy eye and was worried about her son developing a similar problem because of how it had affected her. Initial investigation showed a moderately high hypermetropic prescription which put the child at risk of developing a lazy eye or a turn, this meant we had to put drops in. I went from being quite nice to being horrible in one fell swoop as far as the child was concerned. After the drops had taken effect a bit more plus came out for overall refractive error of about +9.00 with -2.00 cyls. However after he had had time to adapt to wearing the trial frame he grew to appreciate the clarity he was seeing with compared to the without, so by the time he had chosen his glasses he was happy and I got a high five on the way out! I didn't get a chance to do the collection sadly but I can only hope it was similar to the viral video of Piper, the 10 month old.

Sunday, 4 October 2015

Eye health week

So last week was national eye health week which saw a blaze of promotion about the health of eyes from the College of Optometrists (which you can read about here). However an eye test doesn't just check the health of the eyes and prescription; it can also indicate a number of general health conditions and eyesight can have a profound impact on people's daily lives.

Take for example Mrs A who I saw a few weeks ago. She had previously been referred for cataracts 6 months ago, but had recently been told that there was still another 12 months or so to wait before she could have the operation. Although her vision was still reasonably good (6/9ish) she was having terrible trouble with glare and had recently had a couple of falls. To young, healthy people this may not seem that serious but to an elderly lady it can have a profound effect on their mobility, confidence and health with hip fractures having a 30 day mortality rate of over 9%. As it is up to the hospital who they see and when, we couldn't promise that she would be moved up the list but wrote a letter to the hospital explaining the effect it was having on her life.

As the eye is the an extension of the brain and has some fine (and relatively easily visible) blood vessels, it can highlight a lot of systemic conditions. For example a small haemorrhage in the retina may be an early indicator of high blood pressure or diabetes, so in the cases I have seen one I have referred them off to the GP to have their blood pressure and blood glucose checked.

Just because a condition is controlled with medication it doesn't mean it won't cause any problems. Unfortunately medication used to control systemic conditions can also cause problems. Steroids for example are used as anti-inflammatories in conditions such as ezcema or asthma, but long term use can lead to early development of cataracts. It can be a delicate balance between controlling a condition and the ocular side effects. Vigabatrin is used to treat epilepsy to control seizures, however it can cause irreversible visual field loss. Therefore patients on Vigabatrin need to have frequent visual field screening to ensure they don't develop any field defects.

An eye test is not just a simple cause of determining whether someone needs glasses it is also a chance to examine how a patient's eyes are affecting their life and how the patient's life is affecting their eyes.