Risk of thermal harm from therapeutic and cosmetic energy-based medical devices: Notice to industry

August 21, 2020

On this page

• Purpose and background
• Requirements to mitigate potential thermal damage of energy-based medical devices

Purpose and background

Health Canada requires scientific evidence to demonstrate an acceptable risk-benefit analysis for energy-emitting medical devices:

• used primarily for therapeutic and cosmetic treatments
• where the energy source is key to the claimed mechanism of action

This notice applies to energy-based medical devices for therapeutic or cosmetic indications intended for sale in Canada. These devices include:

• laser
• ultrasound
• radio frequency (RF)
• intense pulsed light (IPL)
• light emitting diode (LED)
• other thermal energy sources

These devices are frequently used in non-medical clinics or beauty salons. The end user applying treatments in these settings may have limited training or knowledge of the risks associated with energy-based medical devices. For this reason, Health Canada is unlikely to consider labeling mitigations alone (for example, requiring constant applicator motion, warning of potential burns, or recommending use only by trained professionals) to be adequate mitigation for products with identified thermal injury risks.

This notice does not apply to surgical systems intended primarily for soft tissue:

• incision
• ablation
• excision
• hemostasis
• vaporization
• photocoagulation

Requirements to mitigate potential thermal damage of energy-based medical devices

Effective immediately, class III and IV medical device licence applications for these types of devices need to include detailed skin temperature testing quantifying induced temperature over time.

This testing must be performed under the system's worst case exposure conditions, for example:

• minimum spot size
• no applicator motion
• maximum power output
• skin contact with the applicator

Testing should represent all Fitzpatrick skin types that the system is indicated to treat for applicable energy sources. Manufacturers of class II medical devices should also ensure similar testing has been conducted and is available on request.

A maximum skin temperature above 45°C without an objective and scientifically sound rationale:

• will be deemed unsafe
• may be grounds for the refusal of the licence application or amendment

Please note:

• temperature measurements must be taken at the surface of the skin and not at the surface of the applicator
• temperature testing data should include the maximum stable skin temperature that can be achieved under worst case exposure conditions

Manufacturers will need to:

• demonstrate in their application that the benefits of their device outweigh all patient risks
• include data which clearly demonstrates that all hazards related to potential thermal damage to the skin have been:
• thoroughly assessed
• removed or sufficiently mitigated by product design

Please note that as safety and effectiveness requirements continue to evolve, a comparison to existing, licensed devices alone will not be sufficient to support a new system's thermal safety. Device-specific testing will be required.

Please direct any questions or comments regarding the content of this Notice to the following:

Medical Devices Directorate
Health Products and Food Branch
11 Holland Avenue, Tower A
2^nd Floor
Address Locator: 3002A
Ottawa, Ontario
K1A 0K9
Email: meddevices-instrumentsmed@hc-sc.gc.ca
Telephone: 613-957-7285

References:

Moritz, A. Re, and F. C. Henriques Jr. "Studies of Thermal Injury: II. The Relative Importance of Time and Surface Temperature in the Causation of Cutaneous Burns*." The American journal of pathology 23.5 (1947): 695.

IEC 60601-1:2012 - Medical electrical equipment - Part 1: General requirements for basic safety and essential performance - Edition 3.1