Center for Diagnostic Imaging (CDI), the nation’s leading provider of comprehensive radiology services, announced today the appointment of Kim Tzoumakas as Chief Executive Officer to lead the company’s next phase of growth. Tzoumakas succeeds Rick Long, who successfully led the company for the past six years and developed the company’s network of diagnostic imaging clinics and radiologist partnerships across the country.

Tzoumakas most recently served as CEO of 21st Century Oncology (21CO), one of the largest integrated cancer care networks in the world with 347 locations in the U.S. and several Latin American countries. At 21CO, Ms. Tzoumakas successfully partnered with more than 1,000 physicians and more than 3,000 team members to accelerate growth through a focus on clinical delivery and patient satisfaction.

“I am thrilled to be the CEO of CDI,” said Tzoumakas. “It gives me the opportunity to partner with physicians on best in class patient care, lead a strong team with solid partnerships, and further expand CDI’s radiology services across the country. Trends toward more cost effective, high quality care in outpatient settings have positioned CDI for great success over the next several years and I am excited to be part of this next phase of growth for the company.”

“Kim has a proven track record of building an organization with a strong commitment to patient care and clinical quality,” said Long. “This competency paired with her background in developing strong partnerships with physicians and other providers will ensure her success in taking CDI to its next level of success.”

“The success we saw Kim achieve at 21CO as a result of her drive, strategic focus, and ability to forge strong relationships was key to our decision to appoint her to succeed Rick Long,” said Alex Carles, Managing Partner of Wellspring and CDI Board Member.

“My vision for CDI is to be the leading radiology provider across the country while partnering with the highest caliber physicians, strategic partners and team members,” said Tzoumakas. “The strength of the Wellspring and CDI partnership will allow us to expand our radiology services and grow our network across the country. Radiologists and patients alike will benefit from the investments we will make in our people, technology and service.” 

About Center for Diagnostic Imaging (CDI)

Founded in 1981 and headquartered in Minneapolis, Minnesota, CDI is one of the nation’s leading providers of high-quality diagnostic imaging and interventional radiology services through its network of imaging centers, ambulatory surgery centers, and mobile imaging solutions. The organization, with nearly 2,000 associates nationally, is committed to delivering clinical excellence in communities across the U.S. driven by its affiliated subspecialized radiologist network, compassionate, safe and cost-efficient care, and superior service to referring providers and patients. CDI has been owned by Wellspring Capital Management since March 2019. For additional information, please visit 

About Wellspring Capital Management

Wellspring Capital Management is a leading private equity firm headquartered in New York. Since its founding in 1995, Wellspring has raised over $4.5 billion of initial capital commitments through six private equity funds. Over the past 25 years, Wellspring has invested in over 45 platform investments across various segments of the U.S. and global economies. Wellspring’s objective is to bring partnership, experience and value creation to each investment. By teaming up with strong management, Wellspring seeks to unlock underlying value and pursue new growth opportunities through strategic initiatives, operating improvements and addon acquisitions. The firm functions as a strategic partner, providing management teams with topline support, M&A experience, financial expertise and access to resources. For additional information, please visit