Protection Against Radiation

Bone fractures, pneumonia, gallstones or tumors – doctors use radiological methods to look inside the human body for diagnostic purposes or as a treatment. Some of these methods sometimes result in high radiation exposure. The patient cannot avoid it, but doctors and medical staff can protect themselves.

Together with MAVIG GmbH from Munich, a German company that sells high-quality medical products and personal protective equipment, Frank plastic has developed and designed innovative radiation protective glasses. These glasses can be worn, for example, by employees in specialist medical practices and hospitals who use X-rays for diagnostic imaging or as a treatment method.

The new glasses protect against X-rays and are equipped with an integrated attachment for an eye lens dosimeter. They are the world’s first radiation protec­tive glasses with an integrated HP(3) dosimeter. HP(3) is a measurand for radiation exposure to the eye lens. Depending on the version of the glasses, it is possible to integrate up to three dosimeters. A standardized ­dosimeter head enables evaluation facilities to ­easily integrate the respective detector technology into the dosimeter head. “The glasses meet a number of require­ments in terms of their functionality, design and ergonomics,” says Martin Schmid, Product Manager of MAVIG.

Consistent Radiation Protection
Requirements include the glasses being positioned as close to the eye as possible and protection for the temporal region. “This is the only way to ensure continuous frontal and side radiation protection,” emphasizes Patrick Straub, Key Account Manager at FRANK plastic. Despite the heavy lens, they should be as comfortable to wear as possible. The glasses must not restrict or impede the work that has to be carried out. The material needs to be easy to clean and disinfect and needs to be able to support the heavy lenses effectively. Last but not least, it must be possible to replace the dosimeters quickly by hand. The dosimeters are sent to an evaluation facility to ascertain the occupational radiation exposure. This facility analyzes the data and then erases the dosimeters. The dosimeters are then packaged in a new capsule and sent back to the user. The dosimeters can then be reused in the glasses.

The glasses are a joint development of MAVIG and Frank plastic and comprise multiple components that are manufactured from various different plastics. For example, the frame is made of polyamide, the temples are made of a softer thermoplastic elastomer (TPE), and the earpieces are made of glass fiber reinforced polyamide. The glasses are versatile and adaptable as the length and inclination of the temples can be adjusted and flexible nose pads are used. The radiation protection is continuous from the nose to the cheekbones. “We have made the frame as light as possible, but it is still stable, meaning the glasses are durable enough for everyday use in a hospital or medical practice,” explains Straub. When selecting the plastics, alongside the mechanical properties, the main focus was on biocompatibility. This means the plastic is compatible with the human organism and will not trigger any allergies, for example.

A Look Inside the Body

In 1895, Wilhelm Conrad Röntgen discovered X-rays and received the first Nobel Prize in Physics for his discovery. These days, X-rays are a widely used and popular imaging technique. It exploits the fact that body tissue has different densities, meaning the X-rays pass through it with varying degrees of effectiveness.

In computer tomography (CT), also referred to as layer X-rays, a tube in which X-rays are generated rotates around the patient. Once the radiation has passed through the different tissues in the body, a receiver absorbs it again. From this information, computers then calculate a cross-sectional image that the radiologist can view and evaluate on a monitor. This allows three-dimensional images to be generated, which provide much more information than two-dimensional X-ray images.

A magnetic resonance imaging scanner (MRI) generates an image of the inside of the body using a strong magnetic field and radio waves. During this process, the body is not exposed to any radiation, except comparatively low-energy radio waves.

When it comes to assembling the plastic glasses, the main challenge for FRANK plastic is hermetically sealing the outer parts with a lead foil. This is essential to protect the head against radiation. “But the foil also needs to be perfectly adhered due to cleaning. This is the hardest process during assembly,” says Straub. FRANK plastic supplies the fully assembled glasses in cases to MAVIG. The lenses and dosimeters are then inserted. The lenses are made of the highest quality optical radiation shielding glass and are anti-glare. Excellent light transmission and optically flawless transparency, as well as the most precise machining and incorporation into the respective version are guaranteed. The lenses also offer a wide range of vision corrections as required by the respective user.

Those involved are extremely pleased with the success of the project so far. “Our partnership has been exemplary. It has ensured that we have been able to implement our project within the planned time frame,” says Schmid, describing the first project that MAVIG and FRANK plastic have worked on together. During a lively exchange of information, the team worked out what each individual component needed to be able to do and then implemented this in prototype production. “Together with MAVIG, we have developed intelligent, detailed solutions for connecting the individual components and have selected suitable plastics and plastic combinations based on our extensive material expertise,” explains Straub. After all, it is the materials used and the individual production steps that determine the quality and service life of the glasses. Series production is planned to start this year.


Patrick Straub

FRANK plastic AG

Key Account Manager

Phone: +49 7486 181-324

© gerenme —, MAVIG