Fundamentals of Lasers and Light Devices in Dermatology

Abstract

This chapter examines the historical development of the laser and the properties and characteristics of the electromagnetic spectrum and light that make laser and intense light sources (ILS) uniquely suited to a wide range of medical and dermatological interventions. The mechanisms for producing light from different active media are described to underpin the differences between lasers, intense light sources and light emitted diodes (LEDS). Medical laser devices are described in terms of active media, emitted wavelengths and clinical applications, together with the rationale and requirements for different beam delivery techniques and technologies. The terms and definitions for describing the properties of laser and light beams are introduced to lead the reader to a better understanding of the light-tissue interactions that underpin medical laser and light applications and determine system choice for a given presenting condition. Chromophores and light-tissue interactions are examined in the context of beam properties and the theories of selective photothermolysis and extended theory of selective photothermolysis to explain laser and light-based clinical applications. The requirements for safety management of laser and light devices are presented by explaining the current classification system, labelling and associated hazards of laser and intense light sources, supported by methods of safe working within the Laser Controlled Area. The chapter concludes by stipulating the training requirements and expected ‘competencies’ of key personnel working within a laser or intense light facility.