As federal prosecutors gear up to tackle more Medicare fraud as part of a nationwide initiative, the U.S. attorney in Tennessee has been tackling a few Medicare cases of his own. U.S. Attorney Edward Yarbrough's office filed a lawsuit in U.S. District Court in Middle Tennessee, alleging wrongdoing by a Georgia diagnostic imaging company with three clinics. The lawsuit was the second local Medicare fraud case filed in a matter of days by federal prosecutors in Tennessee.