Anne-Lise Høg Lejre holds a Bachelor of Science (chemistry) degree from Denmark’s Technical University, furthermore she holds a degree in Marketing from the Copenhagen Business School.

Anne-Lise has been employed at the Danish Technological Institute for 10 years. Her specilaist fields include testing, characterisation and analysis of polymer materials, mechanical and physical testing of polymer materials, surface modification and characterisation, ageing studies and assesment of damages with emphasis on plastics and surfaces for biomedical applications.

She is also a project co-ordibator at an EU funded project in the field of biomaterials and medical devices.

Polymers degrade during service with progressive loss of properties such of appearance, mechanical strength and overall performance. Degradation caused by the service environment, produces chemical reactions or physical changes eventually leading to product failure. Some polymers degrade more rapidly than others. Sources and causes of these degradations and how degradation occurs are described in the presentation.

The manufactures of medical devices shall demonstrate, although the medical device has been subjected to stresses occurred during distribution, storage, handling and ageing, the integrity of the medical device is maintained at least for the claimed service time under conditions specified by the manufacture.

The most valid ageing program is to age the medical device under real-life service conditions for the intended lifetime. Since such testing would be completed prior to market release, this approach would delay, unnecessarily in many cases, the introduction of potential valuable technology to the market with loss of benefit to the patient. Avoiding unnecessary delays in bringing the technology to the market is the reason for utilising accelerated ageing test programs.

Ageing phenomena, such as physical ageing, thermal ageing, chemical ageing, photochemical ageing, biological ageing and combinations of several ageing factors are addressed in the presentation.

Furthermore a design guideline and a test protocol for accelerated thermal ageing is included.