A radiology department which has already been the subject of three separate inquiries into mismanagement is to be the subject of yet another inquiry, this time into its breast-screening unit.

Hammersmith Hospitals trust's imaging department has been investigated three times after it built up a backlog of thousands of x-rays.

It was criticised for having 'little evidence' of clinical audit, 'poor morale' and 'unsatisfactory arrangements' for magnetic resonance imaging.

The breast-screening unit at Charing Cross Hospital is now to be investigated by the regional quality assurance unit after an error was discovered on one woman's file. The unit was alerted once the error was discovered and a review of case files will be taking place.

A spokesperson for the trust said 'the woman involved was not compromised in any way', but that the error had raised the possibility of further problems and that a review of files would therefore take place. She denied that this latest problem had anything to do with the previous inquiries.

It is understood the inquiry will look at symptomatic and asymptomatic breast screening.

The last government inquiry into the imaging department, led by Professor Ian Cameron, was never published and has led to fears among some staff that its recommendations were never fully acted on.