Capt. Christy Barton performs a cataract test on a Ghanaian woman. U.S. Air Force Capt. Christy Barton performs a cataract test on a Ghanaian woman in Tamale, Ghana, during Exercise Med Flag 2006 on Sept. 12, 2006. Med Flag is a medical-training exercise in which medical personnel from U.S. Air Forces in Europe are treating residents and training local health care workers. Barton is an optometrist assigned to the 52nd Medical Group. SHARE: Download: Full Size (0.1 MB) Credit: VIRIN: 812098-E-VWN40-582.jpg Photo Gallery