This is the sixth edition of the Royal College's clinical radiology referral guidelines, which goes to show how successful it has been. With radiology advancing so rapidly there is plenty of new information contained in this edition.
The guidelines are also available online, which is an excellent way of viewing them.
It is stated that they are intended as a guide for referring clinicians and are not to be used to restrict practice. Even small doses of radiation are not entirely without risk, so we should decide whether the investigation does actually confer clinical benefit.
Radiation risk explained
I was interested in a table showing effective doses of radiation from diagnostic medical exposure. I was unaware that CT scan of the abdomen or pelvis gives a 16-fold increase in radiation risk over plain abdominal X-ray, which is the equivalent to over four years of natural background radiation.
It is estimated that the additional lifetime risk of fatal cancer attributable to abdominal CT examination in an adult of one in 2,000. After reading this I felt grateful that as GPs we do not have access to CT scanning.
There are questions to ask prior to ordering an investigation - has it already been done? Do I need it? Do I need it now? Is this the best investigation? Have I explained the problem? Are all the investigations needed?
I found the section giving a brief discussion on actual imaging techniques, and their risks, benefits and short-comings very useful.
CT scanning, MRI scanning, interventional radiology including angiography and ultrasound are all discussed but I was particularly interested to read about positron-emission tomography co-registered with CT (PET and PET-CT). I have several patients who have had these investigations and I have not fully understood what is involved.
A GP resource
Actual disease areas are covered in table form with short notes on indications for different investigations and their degree of usefulness in each disease.
This would be very useful for junior doctors as a reference. While many of the investigations tabled are not available for us as GPs to order, it is nonetheless interesting.
There is a comprehensive section on the usefulness of different investigations in the diagnosis and staging of different forms of cancer.
I was also interested in the section on investigation of breast disease. Other disease areas covered include chest and cardiovascular systems and interventional radiology, much of which is less relevant to GPs as many of the investigations are specialised and available only to hospital doctors.
This book is packed with useful information. It is not a book to read from cover to cover, but is a great little reference book with excellent advice.
Dr Lewis is a GP in Windsor, Berkshire
Making best use of clinical radiology services
Royal College of Radiologists
1-4 copies: £15 each
5-49 copies: £13 each
For more information see www.rcr.ac.uk or email: MBUR6@rcr.ac.uk.