Seborrhoeic keratosis imaging in high-definition optical coherence tomography, with dermoscopic and reflectance confocal microscopic correlation

Although it is one of the most common skin tumours seen by dermatologists, seborrhoeic keratosis (SK) may show a wide variety of clinical and dermoscopic presentations.1, 2 Therefore, its differentiation from other skin tumours, including melanoma, can sometimes prove challenging.3 Several non‐invasive skin imaging techniques have emerged in recent years aiming for a higher accuracy in in vivo diagnosis. These include dermoscopy, reflectance confocal microscopy (RCM) and high‐definition optical coherence tomography (HD‐OCT).4, 5 HD‐OCT (slice and en face modes) provides a fast morphological imaging with cellular resolution and a penetration depth into the skin that allows discrimination of architectural patterns and cytological features in the epidermis and both the papillary and reticular dermis.6-10 Herein, the aim of our study was to describe HD‐OCT features of SK with variable clinical appearances, with dermoscopic and RCM correlation.