Patients in Tayside are facing journeys of up to 500 miles for specialist treatment including sex changes, the Tele can reveal.
Information from a freedom of information request shows that almost one patient a week was sent south of the border for treatment not available in Tayside in 2016/17.
Hospitals in the north of England including Newcastle, Liverpool and Manchester, and as far south as Birmingham, Sheffield and London, treated patients referred from Tayside in the previous financial year.
The specialisms involved included cardiology, respiratory medicine, neurosurgery, gender reassignment surgery and paediatric surgery.
Patients are sent to hospitals outwith Scotland by NHS Tayside and health trusts in England then bill the Tayside board to recoup the costs of the treatment.
However, the number of Tayside patients being treated by the NHS in England is the lowest it has been in the past four years — down from 53 last year and 68 in 2014/15, when it was at its highest.
A spokeswoman for NHS Tayside said that patients were only referred outwith the region for “specialist surgical procedures that were not available within NHS Tayside mainstream services”.
The figures emerged as the health board released statistics showing some specialist clinical posts have been lying vacant for more than a year.
There were 10 posts in the past 12 months which took longer than 200 days to fill, and 16 which remained open for more than three months in total.
One vacancy in general psychiatry remained unfilled for 340 days and another in paediatrics remained vacant for just over a year.
The health board spokeswoman said: “Providing clinically safe and effective care is always our priority and we take all steps to ensure that we provide appropriate staffing levels.
“National shortages across some specialities affect all NHS Scotland boards.
“As part of addressing this, NHS Tayside has active and ongoing recruitment campaigns to fill medical and nursing vacancies as they arise, including seeking to attract candidates locally, nationally and internationally.”