Supplementary Tests

This test measures how easily your eyes can detect the differences in contrast between objects.

The greatest levels of contrast occur between black and white.

The chart consists of a series of black letters changing to grey and then almost white on a white background. If cataracts develop then the eyes have reduced contrast sensitivity.

 

The central part of the retina at the back of the eye is called the macula.

This is the area of sharp focus. If the macula is oedematous (swollen) the lines on the chart will look distorted.

This can happen with diabetes and age related macula degeneration.

 

8% of men, one in every twelve have red/green colour blindness.

In some people it can be very slight and others more severe.

The Ishihara plates detect red/green colour defects using a series of numbers that you read. Another test called the City Colour vision test detects red, green and blue defects.

 

This appointment costs £28.00

We measure how long your tear film lasts between blinks.

We time it with an instrument called a Tearscope.

The tears in your eyes have three layers. The top layer are lipids (fats), the middle layer is aqueous (water and salt), the bottom layer is mucin (mucous). Deficiency in any of these layers can cause dry eyes. We treat dry eye syndrome by identifying which of the three layers is defective and treating it. One of the treatments are punctal plugs. These plugs block the tears lower drainage channel in the eyelid.

 

We need to measure the pressure of your eye.

The doctor measures your blood pressure and we record your eye pressure.

I will puts some special drops in you eye and use a machine with a blue light to measure the pressure.

 

Sometimes one of the six external eye muscles, in each eye may be weak (paresed).

We need to find out which one is not working properly.

We use red and green goggles, red and green pen torches and the grey chart in the picture, to measure the weakness.

You have to make a cross pattern by putting the red light bar over the green light bar.

 

We can measure how wide an area you can see over, whilst looking straight ahead.

This machine flashes a light and you press a button to tell the machine that you have seen the light.

Our routine screening takes only four minutes for each eye.

We regularly screen patients with a family history of Glaucoma