Medical Devices Legislation and Technical Details
Definition and Scope of Medical Devices
Medical devices are products that have no pharmacological or immunological effect, but are used to improve, diagnose, treat or monitor human health. These devices, which interact directly or indirectly with the human body, play a critical role in diagnostic and treatment processes. Examples include surgical instruments, dental implants, in vitro diagnostic devices and pacemakers.
It is essential that medical devices are safe and effective and are designed and manufactured in accordance with certain international standards. In the European Union, these products are regulated under the Medical Device Directive (MDD) 93/42/EEC. Turkey has also adapted this directive to its national legislation.
93/42/EEC Medical Device Directive: General Requirements
Directive 93/42/EEC introduces specific rules and standards to ensure the safety, quality and performance of medical devices. It guarantees that devices bearing the CE marking meet certain health and safety requirements.
Main Goals:
- Device Safety: To ensure the safety of the device for users and patients.
- Performance: To ensure that the device performs in accordance with its intended purpose.
- Clinical Data: Supporting evidence of safety and efficacy with clinical evaluations.
CE Marking: The CE marking, which ensures the free movement of medical devices in the European Economic Area, indicates that the product complies with health, safety and environmental standards. To obtain CE marking, the device must undergo rigorous testing and complete conformity assessment procedures.
Medical Device Classification According to Risk Groups
Medical devices are categorised into four main classes according to their duration of contact with the human body, their degree of invasiveness and their potential risk level. This classification is based on the rules established under Directive 93/42 / EEC.
Class I (Low Risk Devices)
Features: Simple, low risk devices. Designed for temporary or short-term use.
Examples: Sphygmomanometers, wheelchairs, non-sterile gloves.
Conformity Assessment: The manufacturer’s own declaration is sufficient. However, Notified Body approval may be required for devices with sterile or measuring function.
Rules:
- Rule 1: Non-invasive, simple devices fall into this class.
- Rule 2: Devices with a purely mechanical function are also considered in this class.
- Rule 3: Low-risk devices that transfer fluids or drugs into the body.
Class IIa (Moderate Risk Devices)
Characteristics: Short-term invasive devices and active devices are included in this class. It includes devices that come into contact with the human body for longer periods of time.
Examples: Ultrasound devices, dental filling materials, surgical instruments.
Inspection: Must be audited by a notified body.
Rules:
- Rule 4: Short-term invasive devices (used for less than 30 days) are in this group.
- Rule 5: Devices used in sensitive organs such as the eye or ear are also in this class.
Class IIb (High Risk Devices)
Characteristics: Long-term invasive devices or devices that support critical body functions fall into this class.
Examples: Ventilators, dialysis machines, infusion pumps.
Approval Requirements: Requires extensive clinical testing and Notified Body audit.
Guidelines:
- Rule 6: Devices in contact with body tissues for more than 30 days.
- Rule 7: Devices in direct contact with blood, tissues or organs are included in this group.
Class III (Highest Risk Devices)
Characteristics: Devices with the highest level of risk. Devices that are permanently implanted in the body or support the functions of vital organs fall into this group.
Examples: Pacemakers, artificial heart valves, brain stimulation devices.
Evaluation: Clinical studies, independent laboratory tests and Notified Body approvals are required.
Rules:
- Rule 9: Permanently implanted devices.
- Rule 10: Devices acting directly on the blood circulation or vital organs.
Special Medical Device Groups
1. Active Implantable Medical Devices (AIMD)
Definition: Devices that are surgically implanted into the human body and operate by receiving external energy.
Examples: Pacemakers, nerve stimulation devices.
Safety Requirements: Biocompatibility, long-term safety and reliability of the energy source should be assessed.
2. In Vitro Diagnostic Medical Devices (IVD)
Definition: Devices used for analysing samples taken from the human body.
Samples: Blood glucose meters, PCR test kits.
Requirements: Accuracy, precision and performance tests must comply with ISO 13485. Clinical validity must be ensured.
3. Non In Vitro Medical Devices
Definition: Devices used outside the body or without direct contact.
Examples: Medical imaging devices.
Technical Requirements: Calibration and measurement accuracy of the device must be ensured and instructions for use must be clear.
Risk Analysis: ISO 14971 Standard
The ISO 14971 standard is an internationally recognised standard for risk management of medical devices. All medical device manufacturers use this standard to identify potential hazards, assess risks, control and continuously monitor risks.
Risk Management Process:
- Risk Management Plan: Defines the procedures to be implemented throughout the entire life cycle of the device.
- Hazard Identification: Identification of physical, chemical, biological or mechanical hazards.
- Risk Analysis: Evaluation of the potential effects and probabilities of each hazard.
- Risk Control: Implementation and documentation of measures taken to reduce risks.
- Residual Risk Assessment: Examining whether the risks remaining after risk control are acceptable.
- Risk/Benefit Analysis: Assessing whether the benefits of the device outweigh the risks.
- Continuous Surveillance: Monitoring the device even after it is placed on the market and intervening if new risks are detected.
Conformity Assessment Procedures and Technical File
The conformity assessment procedure of the device varies according to the class of the device. The main procedures are:
- EC Type Examination: An independent Notified Body examines the design and technical documentation of the device.
– Obligation: Especially required for Class IIb and III devices. - Full Quality Assurance System: Production processes are continuously audited by a Notified Body. The quality management system must be documented.
– Technical File: It must contain all documents proving the performance, safety and effectiveness of the device.
– Content: Risk analyses, manufacturing processes, quality control methods, clinical data, sterilisation procedures, labelling and instructions for use.
Safety and Performance Requirements
- Biocompatibility Tests: The device must be biocompatible in accordance with TS EN ISO 10993 standard.
- Sterilisation: Sterilisation processes of the devices must be documented to ensure safety.
- Clinical Evaluation: The effectiveness of the device must be supported by clinical data.
Market Surveillance and Compliance Audit
The competent authorities carry out continuous surveillance to ensure the safety of devices placed on the market. When any adverse event is detected, corrective measures are recommended to the manufacturer or the device may be recalled.
- Market Surveillance Plan: A comprehensive monitoring plan should be prepared to minimise risks.
- Reporting: Adverse events must be reported to the competent authorities.
Declaration of Conformity
The manufacturer declares that the device complies with Directive 93/42/EEC and the relevant standards. This declaration entitles the device to CE marking.
Content:
- Manufacturer Information: Name and address of the manufacturer.
- Device Description: Model, serial number, intended use.
- Compliance with Standards: Indication of the appropriate ISO standards (e.g. ISO 13485, ISO 14971).
- Authorised Signature: Must be signed by an authorised representative of the manufacturer.
Standards and Regulations
MDR (Medical Device Regulation):
New regulation aiming to improve the safety of medical devices by replacing Directive 93/42/EEC.
Changes: More stringent clinical evaluation and certification procedures.
ISO 13485:
International standard for the quality management system of medical devices.
Requirements: Continuous improvement of production processes and documentation.
ISO 10993:
Standard for biocompatibility testing of medical devices.
Tests: Cytotoxicity, haemocompatibility, irritation and sensitisation tests.
EN ISO 15223-1:
Labelling and information requirements for medical devices.
Symbol Usage: Internationally valid symbols should be used on labels.