Soft contacts vs. hard contacts for diving

[Daniel Ho]

Hi guys,

next year in March I am going to do my diving courses (open water and advanced open water) for my coral reef conservation internship in Koh Tao, Thailand (wooohoooo, I am so excited!!!). However, as a short sighted person, I can't really see anything without my glasses (-6.00 D), therefore I have been doing a little bit of research on wearing contacts while diving.

So far, it seems like there are 2 options: soft and hard lenses. From what I have read when searching through the threads, most people prefer soft lenses as they are bigger, so when draining (floating?) the mask, you can just close your eye lids a little bit so the lenses won't get washed off. And they are also gas permeable, so the eyes don't feel dry after the dive. However, according to this article (and several others that I found): Can You Scuba Dive With Glasses or Contact Lenses? it is advised against diving with hard or gas permeable contact lenses as they may suction painfully to the eye due to the increased pressure underwater or may cause blurry vision when air bubbles becomes trapped between the lens and the eye. Which confuses me a little bit, so should I get some kind of soft lenses, which are at the same time non-gas permeable?

As someone who has never used contact lenses before (only glasses) and a non-diver, I appreciate any help and recommendation I can get.

Thank you in advance for the answer!

 

[DavBuc]

You're confusing a few terms.

Going back a bit- the first contact lenses used in the general population were called PMMA, and they did not allow any transmission of oxygen through the lens, for all practical purposes, they were nonpermeable, they had to be fit in such a way that the lens moved quite a bit on the cornea, with each blink. That way the needed gas exchange was done around the lens, because it could not happen through the lens.

Then came RGP lenses, which is short for "Rigid Gas Permeable lenses". These lenses looked and felt very similar to PMMA lenses but they flexed a bit when handled because the lens matrix was porous and allowed "some" gas exchange through the lens in addition to around the lens as it moved with the blink. Ironically, many PMMA lens wearers rejected this new lens because it wasn't as wettable and not as comfortable.

Both of those lenses are still fit today but comprise less than 5% of the population, with RGP lenses far outpacing PMMA lenses.

The vast majority of the vision corrected population who wear contact lenses wear soft lenses, and most of these lenses are disposable, with daily replacement lenses rapidly becoming the lens of choice.

Soft lenses of ANY form are much more permeable than RGP lenses and are the best choice for divers because there is little to no chance of a vacuum forming between the posterior surface of the contact lens and the anterior surface of the cornea- and because soft lenses do not fit nearly as loose as RGP or PMMA lenses and are held in place by the upper and lower lids, there is much less chance of loss even with a flooded mask. And in the event of a loss, disposable lenses are cheap and most patients have several extras on hand, whereas RGP lenses are custom made for the patient and cost upwards of $100 per lens.

Your best option is probably daily disposable lenses, which in your Rx will cost less than $25 for a box containing 30 lenses when purchased in volume.

You're welcome.

 

[BRT]

I have used one or the other for scuba for 30 years now. For awhile I wore both, a gas permeable rigid on top of a disposable soft lens. Sometimes my eyes feel dry with the RGP's that I use now and occasionally one pops out into my mask. so I go on with one lens and the ability to see the lost lens inside my mask, I have been REALLY nearsighted. So far in 30 years I have lost exactly one. While trying to put it back in my eye in an open boat the wind blew it away. On occasion I get blurry vision after deeper dives. I believe it is gas bubbles in the lens, but can't prove that. It goes away after awhile. If my mask comes off under water I close my eyes and deal with it. If it ever is not where I can feel it I'll open my eyes and find out if my contacts come out or not.

 

[DavBuc]

I have used one or the other for scuba for 30 years now. For awhile I wore both, a gas permeable rigid on top of a disposable soft lens.

The only reason to wear an RGP on top of a soft contact lens is in the relatively rare situation where a person has a serious corneal disorder, primarily keratoconus.

 

[Dogbowl]

I have worn soft contact lenses, preferably daily disposables, for scuba diving and all water activities for many years. I did not even know that hard contact lenses still existed, except for a very minor population with very special visual needs.

My prescription is very similar to yours, and unless you have special needs that I am not aware of, you’ll do fine with soft daily disposable contact lenses.

 

[northernone]

No issues with soft contacts.

Just a generic warning about eye infection and the need to be careful with getting dirty water in your eyes. Silt can get trapped behind the lens and scratch.

When my mask has water in it, I close my eyes and empty it. No issues.

Cheers,
Cameron

 

[BRT]

The only reason to wear an RGP on top of a soft contact lens is in the relatively rare situation where a person has a serious corneal disorder, primarily keratoconus.

Not recommending it. Just saying it has been done. If you can't get vision correction because of astigmatism without hard lenses and can't wear the hard lenses because they rub the wrong places wearing both can be an option. I had corneal grafts for kerataconus in the mid 80's. The scar tissue from the stitches gave me trouble for a time. Now I occasionally pop in both when I get discomfort.

 

[stepfen]

I used to use RGP for about 20 years including after I started diving 2 years ago. The only problem I had with them while diving was a bit of blur during the final meters of the ascent due to gas being trapped under them (later I was told that a lot of off gassing happens through the eyes!). The blur lasted few minutes and disappeared soon after I was out of the water. Because of this and the fear of loosing them in one diving trip I did last year I choose to use/try daily soft lenses. They were OK (no blur etc) but I didn't like the procedure of wearing and removing them especially in a dirty environment. That was one of the reasons I decided to have eye surgery. I did it and i think it is one of the best things I've done to myself. If you can go that way, do yourself the favour and consider it. Regards

 

[Edward3c]

I’ve been wearing RGP lenses for the last 26 years of diving without issue. The only time they ‘fog up’ is when I surface after mandatory deco stops, however they clear within 10 minutes.

I’ve never lost one demonstrating mask clearing. Lost both when the glass lenses fell out of my mask and I needed to see to complete deco and the ascent. One went walkies when the wind flipped it out of my eye - that could happen anywhere.

 

[RB7]

Been using soft contact lenses daily disposable ones during multiple dive trips. No issues with blurriness etc my diving is limited to 130ft so cant comment on depths below that. I do close my eyes when clearing mask as I feel the lens may come out if my eyes made contact with water.
Works for me