Medical Analysis and Features of Medical Devices

Medical Analysis

Medical analyses are one of the fastest-growing areas in healthcare. Medical tests help detect a condition, make a diagnosis, plan treatment, check whether treatment is working, or monitor the condition over time. Healthcare professionals request these tests as part of routine examinations to check for specific diseases and disorders or to monitor human health. A wide range of tests and analyses are performed within this scope, from allergy blood tests and allergy skin tests to antibiotic sensitivity tests, bacterial culture tests, bone density scans, cholesterol levels, lactose tolerance tests, hearing tests for adults and children, blood pressure measurements, obesity screening and stress tests, and medication monitoring for treatment purposes.

After all, medical testing and analysis is a medical process to detect, diagnose and monitor diseases, disease processes, susceptibility, or to determine a course of treatment. Medical analyzes such as physical and visual examinations, diagnostic imaging, genetic testing, chemical and cellular analyzes related to clinical chemistry and molecular diagnostics are typically performed in a medical setting.

Medical analyzes are generally grouped as diagnostic, screening and follow-up analyzes according to their purposes:

• Diagnostic analyzes are analyzes performed to detect or confirm the presence of disease in a person with a complaint, usually following reporting of symptoms or based on other medical test results. For example, nuclear medicine is used to examine a patient suspected of having blood cancer. Blood counts are done for a person with a high fever to determine if a bacterial infection is present. Or electrocardiogram readings are needed to diagnose or identify a heart irregularity.
• Screening analyzes are a set of tests and analyzes applied to detect the presence of disease in individuals at risk within a defined group, such as the population, family, or workforce. Screenings are performed to monitor disease prevalence, manage epidemiology, aid prevention, or for statistical purposes.
• Follow-up analysis, on the other hand, is a process applied to monitor the progress of medical treatment or the patient's response to medical treatment.

Medical analyzes can also be classified into different broad groups. Namely,

• Patient observations that can be photographed or recorded.
• The question asked while taking the patient's medical history.
• Physical examination tests.
• Radiological tests in which x-rays are used to create an image of a particular area of ​​the body.
• In vivo diagnostics tested in the body (for example, manometer, gluten challenge test, contractile stress test, bronchial challenge test, oral food challenge or administration of a diagnostic agent and measurement of body response).
• In vitro diagnostics that tests a tissue or body fluid sample (e.g., liquid biopsy, microbiological culturing that detects the presence or absence of microbes in a sample from the body and often aims to detect pathogenic bacteria, genetic testing, blood glucose level measurement, liver function testing, calcium testing, testing for electrolytes in the blood, such as sodium, potassium, creatinine, and urea).

Electromagnetic Compatibility in Medical Devices

Electromagnetic compatibility is the ability of a medical device to operate safely and effectively in its intended electromagnetic environment, without creating excessive disturbances or causing interference (which may interact with other equipment). In this context, immunity should be defined as the ability of a medical device to withstand the influence of various electromagnetic disturbances, for example radio frequency disturbances, electrostatic discharge, power surges and the like. Electromagnetic compatibility (EMC) considerations are important because in some cases these interferences can affect the normal operation of the medical device and pose a hazard to the health of the patient. Emission limits need to be enforced to minimize interference.

Appropriate requirements are set by the international series of standards for medical devices (IEC 60601 Electrical medical equipment, IEC 60801 Electromagnetic compatibility for industrial process measuring and control equipment, and IEC 60101 Safety requirements for electrical equipment for measurement, control and laboratory use). These standards cover a wide range of hazards, including electrical, mechanical and radiation, among others, and are used in most applications to demonstrate the conformity of the medical device in question with applicable requirements. In addition, these standard groups cover a large number of device-specific standards that include certain types of medical devices. Moreover, some standards regarding active implantable medical devices also address electromagnetic compatibility issues.

Low Voltage in Medical Devices

Low-power electronics used in the medical field include devices such as implantable pacemakers, cardiac defibrillators, implantable neurological stimulators, implantable muscle stimulation devices, hearing aids, bone conduction amplifiers, tinnitus blockers, and cochlear implants. Of these devices, pacemakers and hearing aids are the most widely used types and have the largest market share. Advances in electronic technology in both pacemakers and hearing aids are leading to significant performance improvements.

The IEC 60601-1 standard (Medical electrical equipment - Part 1: General requirements for basic safety and basic performance), published by the International Electrotechnical Commission (IEC), consists of a set of standards and is a widely accepted criterion for electrical medical equipment. Compliance with this standard has become a requirement for the commercialization of electrical medical equipment in many countries.

In terms of low voltage safety, power supplies designed for use with medical equipment must comply with the internationally accepted safety standard IEC 60601-1. This standard specifically covers applications where the patient is physically connected to the equipment. As clinical personnel will operate the connected equipment, they are also covered by the specification. The standard in question covers not only the power supply unit itself, but also the equipment it powers. The requirement applies to the entire system.

Sterility in Medical Devices

Medical devices are sterilized in a wide variety of ways, including moist heat (steam), dry heat, radiation, ethylene oxide gas, evaporated hydrogen peroxide, and other sterilization methods, such as chlorine dioxide gas, evaporated peracetic acid, and nitrogen dioxide. Ethylene oxide sterilization is an important sterilization method that manufacturers commonly use to keep medical devices safe.

For many medical devices, sterilization with ethylene oxide is accepted as the only method that effectively sterilizes the device and does not damage the device during the sterilization process. Medical devices made of certain polymers (plastic or resin), metals or glass, or with multiple layers of packaging or hard-to-reach places are also often sterilized with ethylene oxide. About fifty percent of all sterile medical devices in the United States are sterilized with ethylene oxide. Types of devices sterilized by ethylene oxide range from devices used in general health care practices to more specialized devices used to treat specific parts of the body.

Biocompatibility in In Vitro Medical Devices

Biocompatibility, by definition, is a measurement of how compatible a device or material is with a biological system. In the ISO 10993-1 standard, biocompatibility is defined as the ability of a medical device or material to perform with an appropriate host response in a given application (ISO 10993-1 Biological evaluation of medical devices - Part 1: Evaluation and testing within a risk management process).

This standard includes:

• General principles governing the biological evaluation of medical devices within a risk management process
• General classification of medical devices according to the nature and duration of their contact with the body
• Evaluation of relevant data available from all sources
• Identifying gaps in the existing dataset based on a risk analysis
• Identification of additional datasets required to analyze the biological safety of the medical device
• Evaluation of the biological safety of the medical device

This standard applies to the evaluation of materials and medical devices that are expected to come into direct or indirect contact with:

• The patient's body during the intended use
• The user's body if the medical device is for protection, e.g. surgical gloves, masks and other

This standard applies to the biological evaluation of all types of medical devices, including active, inactive, implantable and non-implantable medical devices. This standard also provides guidelines for the assessment of biohazards arising from:

• Risks such as changes in the medical device over time as part of the overall biological safety assessment
• Fracture of a medical device or medical device component that exposes body tissue to new or new materials

Briefly, in vitro biocompatibility tests have been developed to simulate and predict biological reactions to materials when placed in tissues in the body. Biocompatibility is a general expression that describes the ability of a material to be compatible with living tissue. Biocompatible materials do not induce a toxic or immunological response when exposed to the body or body fluids. Biocompatible materials are of great importance for use in medical implants and prostheses to prevent rejection by body tissue and support compatible biological functioning.

Stability in Medical Devices

The medical device stability test is performed to determine to what extent a device preserves the same properties it had during production, within the specified limits, during its storage and usage period. Similar to pharmaceutical products, there are a number of criteria for evaluating the stability of medical devices. For example,

• Chemical criteria (decay, interaction, device packaging and interaction, radioactive decay, production)
• Physical criteria (physical properties, production process, storage conditions)
• Microbiological criteria (sterility, environmental control, antimicrobial efficacy)
• Therapeutic criteria
• Toxicological criteria
• Biocompatibility test

Medical device stability testing is especially needed to determine the shelf life of the product. This test method is used to identify weak links to a product. The influence of high and low temperature and vibration accelerate failure modes more than normal testing approaches. This test is not a pass/fail test. It creates the ability to learn more about the product's design and material limitations, and provides opportunities for continuous improvement of the design before marketing the product.

Stability tests generally include separate test methods such as high temperature step voltage, low temperature step voltage, vibration step voltage, rapid thermal cycling and combined environment. In general, shelf life is determined using two types of stability tests: real-time stability testing and accelerated stability testing.

Our organization also provides medical analysis services with its trained and expert staff and advanced technological equipment, among the numerous test, measurement, analysis and evaluation studies it provides for businesses in various sectors.