HUDSON, Ohio and NASHVILLE, Tenn., April 7, 2015 /PRNewswire/ -- Airis Radiology, a leading national radiology practice, today announced it has acquired Optimal Radiology, a Tennessee-based provider of professional radiology services to hospitals nationwide. The deal brings together two of the country's largest radiology groups, creating a national practice with more than 160 board-certified radiologists who provide radiology services to over 130 healthcare organizations and interpret an estimated 1.5 million exams annually.