Gabriel Willmann, MD, from the Center for Ophthalmology, University of Tübingen, Germany, and colleagues used fluorescein angiography with a confocal scanning laser to evaluate 14 unacclimatized volunteers at baseline (341 m), after ascent to 4559 m within 24 hours, and more than 14 days after return. Four ophthalmologists blinded to the timing of the photographs graded them for presence and location of leakage. The researchers found that none of the volunteers demonstrated retinal abnormalities at baseline; however, at high altitude, 50% of participants had marked bilateral peripheral retinal vessel leakage. No leakage was noted in the central retina; all changes reversed after descent. To see more details visit, www.medscape.com