Obesity is playing an increasingly important and problematic role in radiology. The number of obese patients is constantly increasing, which leads to special requirements in diagnostics and therapy. We have looked at the challenges faced by radiographers when examining and treating obese patients and summarised the most important factors for you.

We speak of obesity when a person has a BMI of 30 or more. This is calculated on the basis of age, height and weight and provides an approximate guide as to whether a person is of normal weight, underweight, overweight or already morbidly obese.

In obese patients, one recognises a clear increase in:

• metabolic diseases such as type 2 diabetes or gout.
• Diseases of the cardiovascular system such as atrial fibrillation, high blood pressure, heart attacks or strokes.
• Diseases of the musculoskeletal system, such as osteoarthritis of the knee and hip joints
• Diseases of multiple organs such as the kidneys, liver, gall bladder in men or even infertility
• Lung diseases such as asthma and an increasingly severe course of infectious diseases - we all remember the pandemic.

These more common diseases are therefore present in radiology as they must be diagnosed.

THE X-RAY TABLE

The X-ray table is mechanically limited in terms of what can be placed on it or the weight with which it can be moved. This limit often varies and must be observed depending on the manufacturer and model - obese patients can quickly exceed this load. Ideally, these devices should have a minimum load capacity of 250 kg. This ensures that the device can handle the increased body weight of obese patients without risk and provides a stable base during the examination.

The Detector

The detector has a significantly lower load, especially if the load is applied punctually. For example, an x-ray image of the heel works wonderfully - however, special care must be taken to ensure that the patient does not stand on the detector when standing up, otherwise it will break in an instant.

Centring

The correct centring of the x-ray beam is just as critical. As the anatomical landmarks are often more difficult to identify in obese patients, the centring may have to be adapted to the altered anatomy. Attention must be paid to the correct focussing of the X-ray field - the size of the anatomical structures of obese patients is often comparable "inside" to those of slim patients. The field size should therefore be set correctly in advance to avoid unnecessarily high radiation doses.

Exposure

Another important aspect are the exposure parameters. The thickness of the fatty tissue requires an adjustment of the parameters, in particular the X-ray voltage (kV) and the tube current (mA), to ensure sufficient penetration of the tissue. Caution is required here: Excessively high kV values can overexpose the image and lead to a washed-out, grey image that limits the diagnostic value.

Die Leistungsfähigkeit

Finally, the performance of the X-ray machine is of great importance. Low-performance X-ray machines are often unable to achieve the necessary exposure parameters required for the examination of obese patients. This can lead to inadequate image quality and thus impair diagnostic accuracy. Before purchasing the X-ray machine, this information should be obtained from the manufacturer or from the machine manual - if the performance is inadequate, patients may simply not be able to be examined.

Positioning

When examining patients lying down, the increased body weight makes it particularly challenging to move the patient horizontally on the examination table. It is usually necessary to involve several people to ensure safe and gentle repositioning. If this is not possible, special table mats with a slideable underside can be used. These products, such as the ProFoam Table Mat, enable patients to be positioned on the examination table with ease by just one person. This reduces the physical strain on staff.

 

 

Another problem is the positioning aids used, which can deform under the pressure of body weight. For example, a wedge used to support the back when the patient is positioned laterally at 45 degrees can give way or become deformed. This can change the planned position of the patient and thus impair the image quality. Dimensionally stable wedges that do not deform under pressure provide reliable support and positioning of the patient - the product range called ProFoam from Pearl Technology is helpful in this respect.

 

©Martin Methlow

Further Information

https://adipositas-gesellschaft.de/

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