Col. Robert Tyszko, an optometrist with the New Hampshire Medical Detachment, N.H. National Guard, Joint Task Force Jaguar, uses a retinoscope to assess the eyes of a patient at a free medical clinic during Beyond the Horizon in Caluco, El Salvador, April 17, 2013. Beyond the Horizon is a chairman of the Joint Chiefs of Staff-directed, U.S. Southern Command-sponsored joint and combined field training humanitarian exercise. (U.S. Army photo by Sgt. 1st Class Horace Murray/Released)