A second MRI scanner at Limerick University Hospital will be installed and working by the middle of next month.
At the moment there is only one MRI scanner in the public acute hospital serving the mid-west region that has a population of 473,000.
HSE chief operations officer, Anne O'Connor, said the health authority is bringing in an external provider and the scanner will be on-site and operating from about December 11.
Ms O'Connor, who was speaking during an update on the HSE's Winter plan, said the second scanner will have a "very significant impact" on the waiting time for MRIs.
The second scan should also help ease overcrowding at UHL due to a combination of insufficient capacity and high attendances in the emergency department.
Ms O'Connor said patients attending hospital EDs wait there for scans and that clinicians are reluctant to discharge patients until they have had their scan.
Meanwhile, the HSE expects the flu season will start in Ireland over the next two to three weeks.
The HSE's assistant national director of health protection, Dr Kevin Kelleher, said they are just beginning to see an upsurge in reported cases of flu.
“We have had 19 hospital cases last week and already one person with the flu virus has been admitted to intensive care,” said Dr Kelleher.
Dr Kelleher said 30 flu specimens have been laboratory tested and they show that the virus types are mainly A and H3N2 that would predominately affect the elderly but the vaccine should give good protection.
He urged pregnant women to get vaccinated because they could get a really bad dose of the flu and die.
“It can be really catastrophic for one or two pregnant women each year.”