Being short sighted, or myopic, shouldn't impact on the ability to safely enjoy scuba diving. There are a number of ways of improving a diver's vision underwater.

Diving short-sighted is a challenge. Myopia should not stop a scuba diver from enjoying the underwater world. Three solutions can address this problem:

1. no correction;

2. contact lenses;

3. prescription mask.

No correction is dangerous! You won’t see your buddy warning about the great white shark approaching! And you won’t see anything except nudibranchs and Christmas Tree worms.

Scuba with Contact Lenses

With contact lenses, gas builds up in the eye during a dive and if not allowed to escape on ascent can cause corneal abrasions. Soft lenses, that allow oxygen to get to the eye, and gas permeable lenses, will allow some gas to escape. Hard lenses with a tiny hole drilled in the centre will also work.

A soft lens in fresh water will shrink because fresh water has less salt than natural tears. A flooded mask on a fresh water dive could make the lens painful and difficult to remove until it returns to normal shape. The opposite occurs in salt water: the lens swells, maybe even flushing it out.

When using contact lenses in chlorinated pools, a rare organism called acanthamoeba can get into the soft lens causing an ulcer of the cornea.

Prescription Lenses Glued to the Face-Plate

With lenses stuck on the mask, an optometrist will need to make up lenses in your prescription with one side flat. The optometrist will check that your eye is in the centre of the lens and then use special glue to attach the lenses to the face-plate.

Mask with Prescription Lenses Built in

Some manufacturers have prescription lenses built into the mask. If the eye centres don’t line up with the curvature of the lens the eye's muscles work harder to pull the eye towards the centre. After many hours this can lead to headaches and eyestrain. On a dive this shouldn’t be a problem as the mask is worn for a short time with usually many hours between dives.

The correction doesn’t cater for every prescription but should be good enough for the short time the mask is used.

Protect the Mask

Whichever type of correction mask you choose, guard it carefully. Many dive masks get smashed on dive boats. A prescription mask will cost more than a normal mask and if broken on a long dive trip it could ruin the trip. After each dive it should be immediately placed into its solid carry box and tucked out of harm’s way.

Using a Combination

Wearing contact lenses on the boat then a prescription mask for the dive, then back to the contact lenses should be discouraged. Dive boats are usually chaos and not the place to be fiddling with contact lenses. Vanity is one of the first things lost on a dive. Few divers finish a dive looking sartorially elegant. Leave the contacts until the day’s diving is over.

What to Take on a Long Dive Trip

If that expensive prescription mask is broken or lost on a dive trip, the trip can be ruined. If it gets damaged, a pair of soft contact lenses and a normal mask can be used as a last resort. Stay above ten metres and be extra careful about having the mask knocked off. Take the ascent slow and easy and keep the contact lenses clean.

Consult the Experts

Don’t let short-sightedness ruin your opportunity to go scuba diving. Whichever method you choose, consult with your optometrist or dive doctor who will offer specialised advice for your situation.