Comparison of Confocal Laser Scanning Microscopy and Optical Coherence Tomography

Abstract

This chapter deals with a comparison of two optical techniques to study human skin in vivo. The two methods, Optical Coherence Tomography (OCT) and Confocal Laser Scanning Microscopy (CLSM), deliver different information on the skin structure, mainly due to differences in penetration depth into the skin, resolution and field of view. On the one hand, our OCT system produces images of 2 × 2 mm2 perpendicular to the skin surface, at one frame per second, with 14 μm axial resolution and 1 to 2 mm penetration depth. On the other hand, video rate CLSM with a modified Vivascope 1000 (Lucid Inc., USA) provides images of 0.5 × 0.5 mm2 parallel to the skin surface with 1 × 5 J..lm (lateral x axial) resolution, but with a limited penetration depth into the skin of 0.25 mm. In this chapter, some examples are presented on the application of the OCT and CLSM systems to study changes in skin due to UV irradiation and ageing. The image analysis, applied to the OCT and CLSM data, is described and a comparison of the results obtained by the two measurement techniques and the interpretation of the images is discussed.