Wellington-headquartered imaging software specialist Volpara Health Technologies will go to the market to raise $A55 million to help fund its proposed acquisition of US medical software company MRS Systems and further growth.

The ASX-listed Volpara, which markets clinical applications for breast screening clinics as well as enterprise-wide software, plans to buy MRS Systems for just over $A21 million and will issue shares to raise $45 million from institutional shareholders and $10m from current investors.