Why do opticians blow air in your eyes?

Why do opticians blow air in your eyes?

Most adults have come to expect to have their eyes ‘puffed’ when they go to the opticians. The machine that blows or puffs in your eyes does so to measure the pressure in the eye. This is of interest, as excessive pressure in the eye is not healthy. It can damage the sensitive nerve fibres that send signals to the brain affecting the picture we see of the outside world.

A bit like blood pressure, there is a normal range for eye pressure. People with eye pressure higher than normal are more likely to get a condition called glaucoma (I must stress that you can also get glaucoma with normal pressure). Glaucoma is a range of conditions where nerve fibres in the eye are damaged affecting the signal the brain receives.

Unfortunately, it has got into the public psyche that the ‘puff test’ is the definitive test for having glaucoma which is not true. In reality, a combination of measures and factors are taken into account. Plus, in the early stages, glaucoma can be difficult to rule in or rule out. That is why repeat measurement of certain tests is required.

A substantial number of people don’t like air blowing in their eyes. If you really don’t like ‘the puff’, there are other ways to check the eye pressure. Depending on your optician, you may be able to have different measurements taken, say with a blue light, but most high street opticians only offer the puff test.