Ophthalmic issues with high O2 exposure? And contact lenses?

[DevonDiver]

Are there any known ophthalmic issues with high %O2 and/or high PPO2 exposure to the eyes? Also with contact lens use?

I ask because my eyes sometimes feel 'blurry', more fatigued and 'sticky' after decompression dives. Whilst I haven't kept an accurate diary to track this, it is a correlation that has occurred to me.

During the decompression phases, I might clear my mask - thus creating a high % (and high PPO2) environment in the mask.

I also wear disposable contact lenses on those dives. I don't believe I notice the same degree of eye fatigue/blur/congestion on diving days where I am not doing decompression; the length of time wearing the lenses are identical (6am to ~10pm).

Thoughts?

 

[BRT]

My wife and I both notice blurry eyes at times after dives. We both wear rigid gas permeable contacts. I believe it is worse after dives closer to NDL's. Stands to reason that anything gas permeable, and this certainly includes soft lenses, would tend to soak up nitrogen and then off gas it and I believe this is what is happening. The blurry look is from gas bubbles in the lenses.

Brian

 

[DevonDiver]

Brian - I don't suffer that effect from dives where I'm not using rich oxygen for decompression. At least, not to the same effect (no more noticeable than any other long day wearing lenses and being on a boat/in sunshine etc).

Also, having the mask full of a rich O2 mixture (exhaled 100% O2) would likely do a very thorough job in desaturating the contact lenses of nitrogen. Or, at least, I would assume so given when I understand of the gas laws.

I'm wondering if that gas exchange to O2 might cause a problem with the lenses... or whether the exposure to O2 causes an issue with the eye. Something more akin to pulmonary O2 effects, but with shorter exposure times due to the fragility of the eye?.

 

[Duke Dive Medicine]

Andy,

There are ophthalmic side effects to repeated exposure to hyperbaric O2 but not at the levels you're using.

Best regards,
DDM

 

[tracydr]

I noticed blurry eyes when I had a chamber ride for 5 hours, 60 feet. It wasn't terrible but the eyes were definitely blurred.
My worst symptoms, though, were cold symptoms. Cough,scratchy throat and runny nose.

 

[uncfnp]

Are there any known ophthalmic issues with high %O2 and/or high PPO2 exposure to the eyes? Also with contact lens use?

I ask because my eyes sometimes feel 'blurry', more fatigued and 'sticky' after decompression dives. Whilst I haven't kept an accurate diary to track this, it is a correlation that has occurred to me.

During the decompression phases, I might clear my mask - thus creating a high % (and high PPO2) environment in the mask.

I also wear disposable contact lenses on those dives. I don't believe I notice the same degree of eye fatigue/blur/congestion on diving days where I am not doing decompression; the length of time wearing the lenses are identical (6am to ~10pm).

Thoughts?

Are you also asking if the high O2 content in the expired air when you equalize your mask could physically change the contact causing decreased focus/blurred vision? That's an interesting question. I would think the dryness of the air alone could cause changes to the contact and at least temporarily interfere with vision correction. Don't know what changes if any the PPO2 would do to the structure of the lens.

 

[BRT]

Brian - I don't suffer that effect from dives where I'm not using rich oxygen for decompression. At least, not to the same effect (no more noticeable than any other long day wearing lenses and being on a boat/in sunshine etc).

Also, having the mask full of a rich O2 mixture (exhaled 100% O2) would likely do a very thorough job in desaturating the contact lenses of nitrogen. Or, at least, I would assume so given when I understand of the gas laws.

I'm wondering if that gas exchange to O2 might cause a problem with the lenses... or whether the exposure to O2 causes an issue with the eye. Something more akin to pulmonary O2 effects, but with shorter exposure times due to the fragility of the eye?.

We noticed it on air years and now notice it on 32%. I've never dove richer than 32%, and never dove without contacts, either Acuvue soft or gas permeable rigids or both together..yes I typed that correctly. I am really convinced that the effect is from tiny gas bubbles in the lenses but maybe the question is if people get the blurry vision who don't wear contacts?

Brian

---------- Post added July 27th, 2013 at 09:07 PM ----------

Are you also asking if the high O2 content in the expired air when you equalize your mask could physically change the contact causing decreased focus/blurred vision? That's an interesting question. I would think the dryness of the air alone could cause changes to the contact and at least temporarily interfere with vision correction. Don't know what changes if any the PPO2 would do to the structure of the lens.

I've never noticed it while underwater but maybe I couldn't tell. It seems to happen after a few minutes back on the surface. Eye drops don't seem to help so I don't think it is dry eyes. And dry eyes don't give the same effect normally.

Brian