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.