MEDIA RELEASE UNSW FACULTY OF
SCIENCE
Watch how you rub: warning on eye spikes
Normal activities such as wearing swim goggles, sleeping face down or doing a gym
workout may contribute to glaucoma and other pressure-related eye diseases, a
new study has found.
“The fluid pressure inside the eye increases - or spikes - during many everyday
activities," says Adjunct Professor Charles McMonnies, of the UNSW School of
Optometry and Vision Science, in a paper published in the journal Optometry and
Vision Science.
“Eye rubbing, yoga head stands, weightlifting, sleeping face down, playing
instruments like the trumpet and swimming laps are some of the many ways of
causing eye pressure spikes,” Professor McMonnies says.
Any touching of the eye through the eyelids raises pressure: light touch causes a
small increase but firm touch can cause a spike three to five times normal pressure,
he says.
Wiping a watery eye and removing eye make-up both increase eye pressure, partly
because they involve eye closure combined with lid contact.
In the case of eye rubbing, the combined effects of eye closure and rubbing forces
on the eye can raise pressure to very high levels; strong rubbing may raise pressure
to 10 times normal levels.
“Normally these pressure spikes are of little consequence and healthy eyes appear
to be unaffected by them. But eye-pressure spikes that are large, and/or last a long
time, and/or occur frequently, may contribute to the progression of pressure-related
eye diseases.”
These diseases include glaucoma - which affects a large proportion of elderly
people and can lead to blindness - and rapidly increasing myopia, or short-
sightedness. Rarer pressure-related conditions include keratoconus, or conical
cornea.
“Avoiding sleeping with the eyes in contact with a pillow or sleep mask may help to
slow the progression of pressure-sensitive eye diseases,” he says.
“Treating itchy, watery, dry or irritated eyes might be the key to avoiding eye
rubbing-related pressure spikes. If you practice yoga exercises, you might be
advised to avoid head stands.
“People who think they might be at risk in relation to these conditions should ask their
eye care practitioner to advise them regarding the significance of pressure spiking
activities.”
Eye rubbing may cause the highest pressure spike but may be only an occasional
harmless event. However, for some people, especially those with itchy eyes, eye
rubbing can be a frequently repeated habit, with rubbing episodes lasting for
minutes that continue to occur over many years.
Taking a deep breath results in a pressure spike of about 33%. If breathing out is
restricted, the increase in pressure is greater. For example, people playing a high
wind-resistance instrument such as a trumpet, oboe, French horn or bassoon,
especially when they play loud and/or high-pitched notes, can more than double
their eye pressure. Professional musicians have been found to be at slightly higher risk
for loss of vision due to their increased hours of playing over many years. The risk
could be significant for someone with glaucoma or a tendency to develop
glaucoma.
The combination of strenuous muscular effort and breathing that is strained can raise
pressure to high levels. One example is weight lifting, especially when lying on a
bench to do bench presses. Another example is doing sit ups on a slant board,
when the starting head position is well below the feet; or doing push-ups, especially
when they are performed with feet raised.
spikes/
Media contact: Professor McMonnies - 02 9958 3046
c.mcmonnies@unsw.edu.au
UNSW Faculty of Science media liaison: Bob Beale 0411 705 435
bbeale@unsw.edu.au
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