Mt Whitney Zone Forums General Discussion Eye Problems on Expeditions

This is a UIAA medical commission article on issues involving the eye on expeditions.

Full story at:
http://www.theuiaa.org/upload_area/files/1/United%20Kingdom(Great%20Britain).png

Some specific info of interest:

Ophthalmology is viewed by the general physician with anything from mild boredom
to abject fear. Unfortunately these fears may have to be faced in the expedition setting
and this paper is designed to equip people with the tools required to assess and
treat an eye problem in the wilderness setting

Snow blindness is more common at high altitude because the air is thinner so more
UV light penetrates the atmosphere. On ascent, UV exposure increases by 4% for
every 300 metre climb. In addition, snow reflects 80% of UV light, greatly increasing
the chances of snow blindness (WHO 1992). So it can take just a few minutes of unprotected
exposure to cause debilitating snow blindness on a glacier at altitude.

Porters are just as vulnerable to snow blindness, so don't forget to
give them sunglasses too! The authors applaud initiatives by porter welfare organisations
who are encouraging expedition leaders to provide their porters with eye protection.

4. High altitude retinopathy
High altitude retinopathy (HAR) is a pathological response by the retina to the hypoxia
of altitude and it was first described in 1969 (Singh et al). Flame shaped haemorrhages
are most commonly seen but optic disc swelling, cotton wool spots, dot and
blot, pre-retinal and vitreous haemorrhages have also been reported.
Although HAR is usually asymptomatic, when a haemorrhage occurs over the macula,
vision can be affected. Previous studies have shown an incidence of HAR from
3.8% to 90.5% with an equal preponderance in males and females (Clarke and Duff,
Wiedman and Tabin). However it appears that about one quarter of people ascending
to moderate altitude in the Himalayas are affected by asymptomatic HAR.

On a personal note:

I have retinal vasculitis and had a central retinal occlusion at sea level in 2007 that left me functionally blind in that eye. During the following three years I climbed many mountains up to 29,035 feet and never had any HAR. I know because every time I returned I went straight to my retinal specialist at UCLA's Jules Stein Eye Institute.

I know it happens, just telling my experience.

I had trouble opening that doc. Google has a Quick View link that seems to work:

UIAA: Eye Problems on Expeditions

I probably should pay attention to these studies since I never wear sun glasses when I am hiking. I don't like to wear them because they change the look of the landscape and I prefer to see everything naturally and then I hate dealing with them every time I take a picture since I need to take them off to look through my lens. I also tend to leave them. In 2009 I brought a pair and managed to make it to day 4 and left them on the Tablelands some where. Medical studies kind of make me wish I had submitted myself for medical testing since I spent over 2 months in the mountains and did not wear sunglasses once.

I do burden myself with them just in case I have to cross snow since I have spent too much time on snow slopes with no sun glasses and it's miserable.

Ken, the link's reference #12, and further reading #2
was for Geoff Tabin, eye MD, and a Seven Summits guy.

recommend his book Blind Corners
Blind Corners. Adventures on Everest

and his Himalayan Cataract Project
which helps the fight against cataracts in sun-exposed populations of third world countries:
Cure Blindness

Advice from an Old Dude:
Other than a burn while on snow without wearing them you won't have to worry about much until the cataracts kick in when you're forty or so. Wear good sunglasses when in the sun. Figure out how to keep from losing them.