• News   Bundling tasks creates greater quality

Bundling tasks creates greater quality

Shorter development times and, as a result, more product innovations are well within the reach of smaller medical technology companies – especially when the quality strategy is right. Product safety necessitates a thorough understanding of the function and system structures right up to the process level, and ideally, a perfect balance between labour, outcome and the costs incurred.
Many medtech companies proudly display a gold-edged certificate documenting ISO 13485 accreditation in their reception areas – because there is no doubt that the systematic satisfaction of regulatory requirements plays a crucial role in quality management in the medtech industry. Regulatory Affairs underpin the safety of medical care and apply just as much to the treatment workflow in the operating theatre as to the analysis of individual appliances in micro medical technology.
Medtech developers aim for products which are generally more patient-compatible and efficient than the preceding versions. In many cases, these properties are evident just by inspecting their surface finishes. Therefore the call for metrology specialists who have the equipment to examine crucial nominal values, such as the roughness, geometry, 3D topography or film thickness of the finished article. In this connection, quality assurance delivers optimal patient-compatibility.
Against this background, medtech parts made of metal or plastic – such as stents, catheter balloons, artificial joints or intraocular lenses – need to be measured and characterised in different ways. Even the slightest discrepancies in the surface properties of these parts alter their efficiency. Without a seamless quality control system, invasive catheters or prosthetic body part replacements could turn into hazardous time bombs.
Measuring and testing are labour-intensive activities that necessarily have an impact on production costs. Manufacturers address this cost driver by regularly subjecting their quality management to fine-toothed comb investigations. As a rule, a sample will have several characteristics to be measured, often in different measurement areas and using different procedures. This process implies high costs; however, these can be undercut by using multisensor surface measurement devices. The secret is to combine several measurement procedures in one device.

The key application is 3D metrology

Fries Research & Technology is one of the technology leaders in this market. There is already a variety of instrument configurations and multisensor techniques  for medicinal applications. This manufacturer has practical experience with instruments for blood sugar test strips, blood pump impellers, plastic micropumps with double actuator, stents and catheter balloons, artificial hip and knee joints, as well as dental implantology, dental filling materials, eye implant surgery and production tool control.
The key application as regards quality assurance is 3D metrology, which delivers precise height values and reproducible statements on 3D parameters such as roughness, contour and topography. The current generation of devices encompasses a range of measurement recorders, such as chromatic distance sensors, interferometric thickness sensors, white light interferometers, confocal area sensors, spectrometers and atomic force microscopes, with resolutions into the sub-nanometre range.

In the multisensor measurement device, all the sensors are linked by a closed circuit with the sample carrier or bench. This enables the samples to be positioned with pinpoint accuracy and be accessible to all the required sensors. Combining a chromatic distance sensor with an atomic force microscope delivers a rapid 3D overview measurement at micrometre resolution level, which can then be followed up with other metrology steps entailing sub-nanometre precision. Measurements here range between 300 micrometres and ten millimetres with height resolutions of three millimetres to 100 nanometres. Films and coatings are measured with white and infrared light sources.

High-tech measurement techniques are indispensable for quality assurance to DIN and FDA standards or compliance with the directive for the restriction on th e use of certain hazardous substances (RoHS). Destruction-free, optical techniques are especially geared to product safety. In all areas where two and three dimensional surface parameters need to be ascertained and reproduced precisely to the micrometre or nanometre, contactless optical measurement is forging ahead as the alternative to tactile measurement. The greatest potential for this measurement technique is its use with soft materials and surfaces with differentiated structural features or low reflectivity.

There are also ways of achieving greater handling safety, for example in blood transfusion technology. Fresenius does more than merely focus on comprehensive fault and damage analysis in order to increase the functionality and quality of medical devices. Its subsidiary, Fresenius Kapi, enhances the efficiency of its automatic blood component separators with new features. At the heart of the Compoflow concept, which can collect exact quantities from a blood flow for preparation, is an opening and closure mechanism for the reliable separation of blood components. The valve is integrated in a blood bag developed in house, and prevents the possibility of application errors that may occur in the manual opening of standard valves.

Documentation is a key ingredient
A key ingredient in quality systems is documentation, and the recording of measurement values and functional parameters is becoming increasingly important in the control of clinical processes. Doctors require documentation of surgical interventions in heart, vascular and transplant surgery for the quality control of clinical operations. Modern ultrasound equipment for flow measurement in blood vessels, such as the SonoTT FlowLab from em-tec, are fitted with a variety of operating modes and measurement probes and provide a detailed record of such parameters as blood flow and pulsatility index while surgery is in progress. The device can also be used to obtain information on extracorporeal circulations, for example in a heart-lung machine. The data stored from each interface can be printed out or reused in other computer programmes. Andreas Beuthner  

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German Summary
Kürzere Entwicklungszeiten und damit mehr Produktinnovationen sind für kleinere Medtech-Unternehmen kein Ausschlusskriterium. Vor allem, wenn die Qualitätsstrategie stimmt. Produktsicherheit bedeutet nachvollziehbare Erkenntnisse über die Funktions- und Systemstrukturen bis zur Prozessebene. Der Idealfall: Ein ausgewogenes Verhältnis von Aufwand, Ergebnis und verursachten Kosten. Der deutschsprachige Beitrag ist nachzulesen auf www.meditec-international.com/medi0611qs