Personal and health information for about 315,000 patients is missing, Emory Healthcare announced Wednesday. The hospital system has been unable to find 10 computer discs containing the data. The missing discs held information on all patients who had surgery at Emory University Hospital, Emory University Hospital Midtown and The Emory Clinic Ambulatory Surgery Center between September 1990 and April 2007. The discs were removed sometime between February 7 and February 20, the investigation has determined. The discs contained data files from an obsolete software system that Emory stopped using in 2007.