With medical devices, failure is not an option. Reproducible examination and measurement of key components and specified tolerances play a key role in ensuring the reliable and repeatable performance needed for simple, single-use catheters right through to the most advanced drug delivery systems.
In order to avoid the rejection of rogue batches. They also need to be able to verify the quality of bought-in materials prior to release from inventory and provide a complete audit trail for regulatory purposes.
Microscopy is a key tool in the examination of medical devices and components as it provides the means to produce the high contrast images needed to spot small imperfections on and below the surface of samples such as catheters and surgical blades. It can also prove beneficial in examining failures, to assess whether they are due to a manufacturing error or misuse.
Optical metrology provides an accurate means to assess prototypes, check the performance of new injection moulding tools and perform lower volume quality control checks.
Automated non-contact video measuring allows multiple measurements to be reliably made on large numbers of small and complex components at a rate that can keep pace with demanding production schedules. With the correct illumination settings, repeatable and reproducible edge detection, even the edges on dark and clear parts can be correctly refracted, detected and reproducibly measured. Non-contact video measurement can also be used to compare CAD vs. actual data and perform real-time SPC.
Key techniques used in QC of medical devises include: stereomicroscopy; extended depth of field; polarizing microscopy; phase contrast; non-contact z-height measurement; non-contact video measuring systems; twin-ring LED illumination; through-the-lens laser auto-focusing (TTL AF); laser scanning; automated edge detection.
Material researchers are developing bone implants made of titanium foam that offer favorable biocompatibility and superior surface roughness and strength. A number of weeks after implanting these plugs into rabbits, CT investigation visualizes and quantifies the bone ingrowth in the ramified porous implant structure.
For some medical components, such as knee or hip implants and hearing aids, the as-built shape of the component is crucial for fast patient recovery and maximum comfort. By digitizing a patient-specific part using a digital laser scanner, the entire geometry can be evaluated on the basis of graphic color diagrams.