New optical examination procedures for the diagnosis of skin diseases

Abstract

Since the establishment of dermoscopy as aroutine examination procedure in dermatology, the spectrum of noninvasive, optical devices has further expanded. In difficult-to-diagnose clinical cases, these systems may support dermatologists to arrive at acorrect diagnosis without the need for asurgical biopsy. To give an overview about technical background, indications and diagnostic performance regarding four new optical procedures: reflectance confocal microscopy, in vivo multiphoton tomography, dermatofluoroscopy, and systems based on image analysis by artificial intelligence (AI). This article is based on aselective review of the literature, as well as the authors' personal experience from clinical studies relevant for market approval of the devices. In contrast to standard histopathological slides with vertical cross sections, reflectance confocal microscopy and in vivo multiphoton tomography allow for "optical biopsies" with horizontal cross sections. Dermatofluoroscopy and AI-based image analyzers provide anumerical score, which helps to correctly classify askin lesion. The presented new optical procedures may be applied for the diagnosis of skin cancer as well as inflammatory skin diseases. The presented optical procedures provide valuable additional information that supports dermatologists in making the correct diagnosis. However, asurgical biopsy followed by dermatohistopathological examination remains the diagnostic gold standard in dermatology.