Tustin-based MemorialCare Medical Foundation said today that it entered a joint venture with Phoenix-based SimonMed Imaging to operate five imaging centers in Orange and Los Angeles counties.

The foundation is the medical group arm of the $2 billion MemorialCare Health System, a nonprofit that is moving to Costa Mesa later this year from Fountain Valley.

The joint venture has been established as Wave Imaging LLC.

MemorialCare Medical Foundation owns 51% of the venture, with Simon, which has 53 facilities in four states, holding the remaining 49%.

Wave acquired the assets of five SimonMed centers in Newport Beach, Huntington Beach, Irvine, Laguna Niguel and Long Beach and renamed those MemorialCare Imaging Centers.