In Canada the figures are even worse: virtually everyone gets an annual x-ray of some sort.61 (It’s also no cause for complacency in the UK, since British doctors order twice the number of certain types of x-rays – barium meal and enema – as their American counterparts.62) The NRPB has recently announced that overall radiation in the UK could be halved without reducing diagnostic effectiveness.
For instance, doctors routinely x-ray for back pain, when it has never been found to do any good at all.63 Skull x-rays have a poor batting average in detecting bleeding in the brain,64 and even the good old chest x-ray, used to detect tuberculosis, is considered a waste of time by the World Health Organization.65 The prestigious medical journal The Lancet admitted that most chest x-rays routinely performed on patients awaiting surgery other than on their heart or lungs were of so little benefit that over a million pounds’ worth of x-rays would have to be done to end up saving a single life.66
The decision of whether you need an x-ray or not also depends on the whim of the individual doctor. An audit of nearly a million day and in-hospital patients has shown that referrals for x-ray varied by 13-fold in general and up to 25-fold for chest x-rays, depending on which consultant was in charge.67
Because the reproductive organs are susceptible to radiation damage, they should always be protected from exposure during x-ray by a lead shield. Nevertheless, in a Consumers’ Association (Which?) report, in 40 per cent of cases the men surveyed had not had their testes shielded, and women were unprotected two-thirds of the time.68 (In a third of cases, no attempt was made to find out if the women were pregnant.) In another study of children, three-quarters of the time the lead shields used to protect the reproductive organs hadn’t been used or placed properly.69
Obviously there are times when x-rays are invaluable – particularly when limbs are first broken (though many doctors insist on constant new shots to check the progress of healing). However, even if your doctor is responsible about ‘dose constraints’ – the new buzzword among radiologists for the least amount of radiation necessary for individual snapshots – you still could be getting more radiation than necessary, largely from ageing equipment. The NRPB has reported that patients in some hospitals receive doses 20 to 30 times higher than necessary for obtaining diagnosis from machines that were, in some cases, 15 years old.70 Just a few years ago Liz Francis, NRPB information officer, said ‘physicists were saying that old x-ray equipment was giving out doses bigger than Chernobyl’.71
Even dental x-rays can subject you to unnecessary risks, since they are often performed by untrained staff who can’t use the equipment properly and who may either need to repeat the exercise or will set the dosage unnecessarily high. Two dentists in the West Midlands escaped suspension by their professional body for using untrained school-leavers to take their x-rays when it became clear that dentists throughout Britain were doing exactly the same thing.
As with most tests, there is a strong likelihood of human error in interpreting the results. One study of Harvard radiologists found they disagreed on the interpretation of chest x-rays half of the time. There were significant errors in 41 per cent of their reports.72
Myelograms and X-ray Dyes
The other danger with x-rays are the contrast agents often used to highlight soft tissue of the body. These dyes have been associated with anaphylactic shock, cardiac instability, and poisoning of the kidneys, particularly among diabetics. In one study, of 319 patients with abnormal kidney function after being given ‘high osmolality contrast agents’, nearly one in 10 required kidney dialysis.73
Contrast agents like iopamidol, used for urographs and angiographs, have also been linked with pulmonary oedema (fluid in the lungs).74 Barium, used for barium enemas, has been known to remain in the bowel and harden. In a patient with with a weakened bowel from diverticulitis, ulcerative colitis or Crohn’s disease, the impacted material could cause the colon to split open.
Many hundreds of thousands of cases of chronic, debilitating back pain have been caused by spinal x-rays, called myelograms. This diagnostic tool involves the use of a contrast medium or dye injected into the canal space and trickled into and around all the discs and nerve roots in the back, which is then x-rayed. Mounting evidence shows that a number of myelogram patients will develop a condition called arachnoiditis, causing permanent, unrelenting pain and rendering many virtually unable to move.
Arachnoiditis is a little-understood condition in which the middle membrane protecting the spinal cord becomes scarred. Nerves atrophy and become enmeshed in dense scar tissue, which presses constantly on the spine. US orthopaedic surgeon Dr Charles Burton of the Institute for Low Back Care in Minneapolis, Minnesota, one of the few doctors to make a study of lumbar sacral adhesive arachnoiditis (LSAA), estimates that it accounts for 11 per cent of patients with ‘failed back surgery syndrome’– where surgery has left them worse off than before.
Although LSAA results from a number of different causes, in Dr Burton’s view it is mainly caused by the introduction of foreign substances into the human sub-arachnoid space. The foreign body most often identified in victims, he says, is iophendylate (known as Myodil in the UK; Pantopaque in the US), the oil-based dye used for myelograms. In LSAA, he says, iophendylate is often found in a cyst within the scar tissue mass.
An estimated one million people worldwide suffer from arachnoiditis caused by this dye, and even this figure could be conservative. Until the 1980s, nearly half a million myelograms were being performed in the US every year.
This is exactly what happened to Brian from Massachusetts. In 1980, after a staphylococcus blood infection causing paralysis, fever and pain, Brian had to undergo back surgery. Before his operation, a myelogram was performed on him, which left residual dye in Brian’s coccyx.
In 1993, after spraining his back, he developed severe muscle spasticity, which caused pain in his legs and lower back. Each night now, the pain forces him out of bed every one or two hours. An MRI scan and x-ray finally revealed that Brian had arachnoiditis and that the myelogram he’d had left residual dye in his coccyx. ‘Eighteen months, and several doctors later, with muscle relaxants, physical therapy, epidermal injections, chiropractic and even seizure drugs like Dilantin, nothing seems to work,’ he says.
Pantopaque was introduced in the US in 1944 after the medical profession was convinced that it was safe. This was despite animal studies showing that Pantopaque caused arachnoiditis (the Swedes banned the product from use in humans in 1948).75 Even though the product was discontinued by Glaxo with the onset of water-based dyes and imaging techniques, iophendylate continued to be used around the world until supplies ran out, and many back specialists continued to maintain that the dye was safe.
At the time, the US Food and Drug Administration and the British government also made no moves to ban oil-based myelograms. ‘Despite the fact that iophendylate was identified as being causally related to the production of arachnoiditis from the time of
