Health hazard Do not underestimate X-ray

Threatening health risks from X-ray examinations

04/12/2012

According to a recent study by US researchers, who found a higher risk of benign brain tumors from frequent X-ray examinations at the dentist, the discussion about the negative health consequences of X-rays has rekindled.

X-rays are a reliable diagnostic tool for many ailments, but the associated radiation exposure always carries a health risk. Therefore, X-ray examinations should be used sparingly and wisely. However, some doctors also tend to interest from increased interest in increased radiographs. The necessary machines are expensive and eventually have to pay for themselves, so that more frequent use of an X-ray is too much rather than too little.

The US researchers around Elizabeth Claus from Brigham and Women's Hospital in Boston and the University of Yale currently reported in the journal „Cancer“ of a significantly increased risk of benign brain tumors by X-ray examinations at the dentist. The study presented not only shows that patients who have been X-rayed at least once a year or more by the dentist, are three times more likely to suffer from a meningioma (special benign brain tumor), but also that, despite the known health risks, the X-ray examinations are fairly generous , However, according to the US researchers, the risks are by no means to be underestimated. Children under the age of ten are particularly sensitive, which has led to a fivefold higher meningioma risk from the dental X-ray examination, according to Claus and colleagues. Dental x-ray examinations play a key role here as the most frequent sources of radiation exposure for people in modern industrialized countries. The current study results make clear that the X-ray recordings in dentist patients should be limited to an absolutely necessary minimum in the future, write the US researchers and thus indirectly express that so far has been far too generous with the X-ray examinations.

The US scientists investigated the association between the development of benign brain tumors and dental radiographs using 1,433 meningioma patients and 1,350 healthy control subjects. All participants stated how many dental X-ray examinations were performed on them, whereby three different X-ray methods were considered: the so-called oral film images (patients bite on a piece of film), the lateral jaw images and the so-called Panorex images (X-ray gun rotates once around the head). Subsequently, the US scientists evaluated the data to determine possible connections with the formation of brain tumors. All three X-ray methods caused a significantly increased risk of benign brain tumors, according to the result of the US researchers. The strongest effect was the Panorex recordings, which have led to a three to five times higher meningioma risk, write Claus and colleagues. Although the x-rays „can be an important tool of diagnosis, more restraint benefits most patients“, so the conclusion of the US scientists.

Under certain circumstances, this medical advice should be taken to heart by German physicians and, in the future, more restraint should be exercised when taking X-rays. Because statistically, every German is X-rayed at least once a year. The physicians calculate around 100 million x-ray examinations each year in this country, whereby, according to critical experts, not every one of these examinations would be required by a long shot. The German X-ray Society in Berlin comes to the conclusion that the number of X-ray examinations and computerized tomography is also high due to the so-called self-referral. The radiologists of the medical society, founded in 1905, refer to the possibility of different medical specialists to carry out their own X-ray examinations. Professor Norbert Hosten of the German Roentgen Society explained that „For example, specialists in bone disease who may be eligible to X-ray certain parts of the body.“ The specialists are „then sub-area radiologists“, so keep hosting.

In the context of self-referral, physicians can then send patients to their own X-ray department and have them examined there. This is a problem insofar as no second opinion is obtained, so the critics of the experts of the German Roentgen Society. Prof. Hosten explained: „Otherwise, if an X-ray examination is used, there is the four-eye principle“, but in the case of self-referral, control by coordination between doctor and radiologist falls away. The coordination is necessary to ensure that X-raying also enables a goal-oriented diagnosis, emphasized Prof. Hosten. If this is not guaranteed, a radiologist would recommend this in consultation with the doctor and recommend a gentler procedure such as ultrasound, according to the expert. Even consumer advocates urge caution in self-referral, since the need for X-ray examination is not always clear. This is how Kai Vogel referred to the consumer center „World Online“ insisted that private insured persons should be on their guard here, since under certain circumstances the reason for the X-ray examination is a purely financial interest of the doctor. „The device has been purchased, then it should also be used“, describes the consumer advocate the problem.

Patients often underestimate the risks of X-rays and computed tomography (CT), as there are no immediate health consequences from the examination. Because health complaints „Actually only occur at very high radiation doses“, the „not expected in ordinary examinations of the skeleton or the teeth“ are, explained Prof. Hosten. A radiation exposure that can cause skin redness or even the destruction of skin tissue and hair loss is usually only achieved when the radiation is used for therapy. However, even the lower levels of radiation can already lead to tissue changes, as the study of the US researchers currently recalls. The X-rays „can cause cancer, and this is independent of the dose“, emphasized the expert of the German Roentgen Society. Only one hit of an X-ray may be enough to sustainably damage the genome of a body cell. It was tissue with rapidly dividing cells, such as the „Intestinal mucosa, gums or bone marrow, where the white blood cells renew regularly in a short time“, particularly at risk, explains Prof. Hosten. However, the risk of developing a tumor after a simple X-ray examination is relatively low, since the radiation dose of modern equipment is extremely low, according to the X-ray expert.

However, the number of X-ray examinations increases the risk of tissue changes. Therefore, the x-rays must be done wisely and it is „important that examinations are not unnecessarily repeated“, emphasized Professor Gunnar Brix of the Federal Office for Radiation Protection (BfS). Here, those affected are invited to their own initiative, because on the avoidance of duplicate examinations „Patients can also take care of themselves“, the BfS expert continues. Professor Brix is ​​particularly concerned about the growing number of CT screening examinations, as here the organism is sometimes exposed to considerable radiation exposure without demonstrable benefits. This applies in particular to examinations of the heart, in which quite high radiation exposure can occur, explained Prof. Brix and added that besides „in many investigations, often as Manager check offered, the benefit has not been proven“ be. „You should not let something like that happen“, warned the expert of the Federal Office for Radiation Protection. Overall, in view of the current study results of the US researchers, patients and physicians are called upon to take a much more critical look at the X-ray examinations in the future and to forego the X-ray in case of doubt. (Fp)

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Picture: Rainer Sturm