The investigation, fuelled by concerns about locum radiologist Dr James Murray, found two cases of lung cancer and a significant dose of pneumonia were among the conditions missed.

It also revealed there was a delay of more than three months between a GP surgery first raising concerns about X-ray work at the hospital in Oban and action being taken – a time-lag described as “unacceptable”.

However, the report, published by NHS Highland yesterday, found the errors did not affect the ultimate outcome for patients.

Liberal Democrat health spokesman Jamie Stone said: “This report confirms that patient care and safety was jeopardised by this rogue radiologist.

“It’s really important that we learn from this incident.”

Dr Murray, who is believed to be in his seventies and graduated from Edinburgh University in 1957, began work interpreting scan images at the Lorn and Islands Hospital in October 2007 when the existing consultant radiologist took sick leave.

A GP practice raised concern about the accuracy of a small number of scan readings that December but it was March 2008 before the board began to investigate the cases identified.

In May, Dr Murray was named in a newspaper as the consultant at the centre of a problem in the Republic of Ireland which had prompted thousands of chest X-rays to be re-examined. Dr Murray then resigned from Lorn and Islands. In June, following revelations in The Herald, NHS Highland announced they were double checking the hospital’s X-ray results.

Nearly 1700 images were re-examined and 45 cases identified where health problems may have been missed. More than 60 ultrasound scans were also repeated and two cases identified where patients had probably been misdiagnosed. One person may have suffered pain from gallstones for eight to nine months because they were not detected earlier.

Dr Ian Bashford, NHS Highland board medical director, said the number of potential errors fell “within the limits of professional acceptability”. He concluded: “I would like to reassure patients that we take seriously issues such as those that led to this review and we have published the report in full to allow everyone an opportunity to look at the findings.”

The report said when Dr Murray was appointed as locum references were obtained from previous employers in Glasgow and Ireland which did not highlight any competence problems.

Dr Murray was employed by NHS Greater Glasgow for six months until March 2006. Some discrepancies in the style of his reporting of X-rays were raised at that time and a team of consultants reviewed his work, but no serious issues were found.

An official probe which covered Dr Murray’s work in Louth and Meath in Ireland found nine patients had been misdiagnosed.

The doctor has been reported to the General Medical Council and may face a fitness to practice hearing. He does not currently hold a licence to practise.