Fianna Fáil say a Diagnostics Fund needs to be set up to cut down on a backlog of people waiting for scans.
Almost 200,000 people were waiting for CT or MRI scans at the end of March, with fears the list may have got longer due to Covid-19.
The party believes the National Treatment Purchase Fund needs to be extended to allow people be covered for scans.
The party's health spokesperson Stephen Donnelly says the problem needs to be fixed quickly:
“The high number of people waiting for procedures such as CTs, MRIs and ultrasounds is especially concerning given that they are diagnostic tests and are used to either confirm or rule out a condition," he said.
"If these tests are being delayed by months and in one in three cases over a year, it could have grave consequences for patient outcomes."
Mr Donnelly said "key information" in the health officials records was missing and if further "information was available we would have a diagnostic waiting list of more than 200,000".