NHS Scotland is spending nearly £4 million sending X-rays, CT and MRI scans to radiologists as far afield as India and Australia amid a major recruitment crisis.

The health service paid £3.8 between April 2017 and February 2018 sub-contracting radiologist services to commercial imaging companies in the UK and overseas in a bid to clear the backlog and speed up diagnoses.

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The figure is up from £2.8m in 2016/17, an increase of more than 35 per cent year-on-year, according to data obtained under freedom of information.

In 2017, more than £200,000 was spent on "overseas reporting" - when scans are sent abroad for review.

It comes after the latest Scottish workforce statistics revealed that vacancies for consultant radiologists were higher than any other medical speciality, with 14 per cents of posts empty at the end of 2017.

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Catherine Sudlow, head of The Centre of Medical Informatics at the Usher Institute and leader of Health Data Research UK in Scotland, said radiologists are in “massively short supply”.

She added: “The NHS, throughout the UK, is sub-contracting work to imaging companies - either based in the UK or overseas, in India or Australia - to get day to day radiology x-rays looked at and read by experts.

“We know that this is not a sustainable way of operating, particularly with increased demand on health care with our ageing population."

Ms Sudlow said that there are often “massive backlogs” of work.

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The shortages are contributing to failing cancer waiting times as radiologists play a vital role in reviewing CT and MRI to diagnose the disease.

NHS Scotland sub-contracts radiology work to three UK-based companies: Medica Reporting Ltd, 4 Ways Healthcare Ltd and Radiology Reporting Online (Everlight).

In 2017/2018, NHS Ayrshire and Arran spent more than any other health board at over £0.73m.

John Scott, Conservative MSP for Ayr, said this spending is “draining away scarce NHS funds.”

Mr Scott added: “While this lack of staff availability should have been addressed before now, the lack of staff in radiology at NHS Ayrshire & Arran is part of the wider problem that health boards across Scotland face in recruiting staff out with the Central Belt - which adds significantly to the cost of health service provision in places such as Ayrshire."

Scott said more needs to be done by the Scottish Government to bring staff to areas outside of the Central Belt and reduce future costs.

NHS Greater Glasgow and Clyde and NHS Highland also spent some of the highest amounts outsourcing radiology service in 2017/2018 – at over £0.7m and £0.69m respectively.

NHS Forth Valley saw the biggest year-on-year increase in spending, from £0 spent in 2016/2017 to £0.19m in 2017/2018.

NHS Lothian, Shetland and Borders did not spend any money on sub-contracted radiology services last year.

Jill Vickerman, BMA Scotland’s national director, said: "The ongoing difficulties in recruiting and retaining doctors of all grades to work in Scotland's NHS is creating significant pressures across the country and is felt particularly severely in certain specialties, including radiology and psychiatry.

"Every vacant post only increases the severe pressure faced by remaining staff and often leads to boards pursuing costly alternative arrangements, so much more needs to be done to make Scotland a more attractive place to work and train if these persistent vacancies are to be filled."

HDR UK is researching automated X-ray reading, carried out by computers. However, Catherine Sudlow said developing these “automated systems” will take a long time.

A Scottish Government spokesman said: “We are working with the Royal College of Radiologists to increase training places and improve recruitment.

“Following a successful global advertising campaign, health boards are currently shortlisting candidates for consultant grade radiology posts across the country and plan to appoint successful candidates as soon as possible.

“We are also investing around £4m in a Radiology Transformation Programme.

“This will significantly improve diagnostic imaging capacity across Scotland and supports our commitment to delivering some of the best radiology services in the world.”