Navigation Links
High-altitude climbs may cause corneal swelling, but do not appear to affect vision
Date:2/8/2010

Swelling commonly occurs in the corneas of mountain climbers, but does not appear to affect vision at altitudes of up to 6,300 meters (about 20,670 feet), according to a report in the February issue of Archives of Ophthalmology, one of the JAMA/Archives journals.

"High-altitude mountaineering is a popular recreational sport among healthy lowlanders," the authors write as background information in the article. "As a consequence of the exposure to hypobaric atmospheric conditions with a consecutive decrease in oxygen saturation, high-altitude climbing may lead to acute mountain sickness and the rare but potentially fatal high-altitude cerebral edema." Changes to the cornea, the transparent membrane covering the front of the eye, also occur during high-altitude climbs and may cause potentially hazardous vision loss.

Martina Monika Bosch, M.D., of University Hospital Zurich, Switzerland, and colleagues studied the effects of high-altitude climbing on corneal thickness among 28 healthy volunteers climbing Mount Muztagh Ata in western China. The mountaineers were randomly assigned to two different ascending paths, with one group being allotted a shorter time to acclimate before ascending to 6,265 meters. Corneal thickness, visual acuity and blood oxygen levels were measured in climbers before, during and after their ascent, and symptoms of acute mountain sickness were also assessed.

In groups with both patterns of ascent, corneal thickness increased with increasing altitude and decreased after descent, and the amount of decrease in blood oxygen levels paralleled this increase. The group with the shorter acclimatization time experienced a greater increase in corneal thickness. However, no significant decrease in visual acuity was observed in either group.

When controlling for age and oxygen saturation, there was a correlation between symptoms of mountain sickness and corneal thickness. This was possibly due to these individuals' higher overall susceptibility to inadequate oxygen supplies.

The exact cause of corneal swelling during ascent remains controversial, the authors note. The current findings suggest that the body's delivery of oxygen to the aqueous humorthe fluid inside the eyeball, between the cornea and irismay be more important in corneal oxygen levels than previously thought.

"It seems that visual acuity in healthy corneas is not adversely affected despite the presence of edema at altitudes up to 6,300 meters," the authors conclude. However, it is likely that ascents to more extreme altitudesabove 8,000 meters or about 26,000 feetmay induce greater damage to the cornea and lead to dangerous visual loss.


'/>"/>

Contact: Martina Monika Bosch, M.D.
martina.boesch@usz.ch
JAMA and Archives Journals
Source:Eurekalert

Related medicine news :

1. VivoMetrics LifeShirt Going to South Pole to Uncover Clues to High-Altitude Illness
2. Amilpar - Revenues Increase by 26.5% and Adjusted Net Income Climbs 28.7% in 2008
3. James Chippendale Climbs the Mountain of Life
4. Doctors miss major cause of infertility and obesity
5. Herbal Remedies Can Cause Cardiac Problems
6. No Surprise to David Perecman And Other Personal Injury Attorneys, Vehicles Lead All Causes of Injury at New York Hospital
7. Mental illnesses are second leading cause of time off work in Spain
8. Tobacco Toxin Helps a Protein Cause Lung Cancer
9. How sunlight causes skin cells to turn cancerous
10. Evolving Strains of HIV May Cause Wave of Drug Resistance
11. American Lung Association Report Card: Federal Government Makes Major Strides; Most States Flunk for Neglecting to Prevent Tobacco-Caused Disease
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/28/2017)... (PRWEB) , ... June 28, 2017 , ... ... a one-day corporate governance program for mid-market executives as a kick-off to the ... held Sunday, Sept. 24, 2017 on the University of Pennsylvania campus, followed by ...
(Date:6/28/2017)... (PRWEB) , ... June 28, 2017 , ... ... insurance management and financial planning assistance to clients in southern Montana, is announcing ... offered by Zoo Montana. , The outreach programs offered by Zoo Montana provide ...
(Date:6/27/2017)... ... June 27, 2017 , ... Excel Medical, ... Finnegan to the position of Executive Vice President, Sales and Marketing. Finnegan is ... telehealth and medical device sales leadership. He has received industry recognition for innovations ...
(Date:6/27/2017)... , ... June 27, 2017 , ... ... solution for many of the health care industry’s hospitals and provider groups, has ... financing portal for select customers. Parasail Health is a San Francisco health-finance startup ...
(Date:6/27/2017)... ... 27, 2017 , ... A January 18th article on medGadget reports ... billion by the year 2024 according to a new report. The article also notes ... from titanium. Los Angeles area clinic Beverly Hills Periodontics & Dental Implant Center says ...
Breaking Medicine News(10 mins):
(Date:6/9/2017)... INDIANAPOLIS , June 9, 2017 /PRNewswire/ ... diabetes. In a further effort to help spread lessons ... this condition, the International Diabetes Federation (IDF) and Eli ... come together for the second phase of the Bringing ... (BRIDGES 2), reaffirming their commitment to helping people with ...
(Date:6/8/2017)... Texas , June 8, 2017 /PRNewswire/ ... a leading developer and manufacturer of diagnostic ... announced today that Cressey & Company LP ... firm, has completed a growth-focused investment in ... a majority ownership position from selling shareholder, ...
(Date:6/7/2017)... , June 6, 2017  Diplomat Specialty Infusion Group, a brand ... environment to its Iowa location. ... now features an ISO 7 cleanroom—the standard needed to ... with a low level of pollutants. ... nutrition consumers and better serve our Iowa ...
Breaking Medicine Technology: