Vascular Features of Nail Psoriasis Using Dynamic Optical Coherence Tomography

Background: Nail psoriasis is a painful and disfiguring nail disease that often leads to invasive biopsies. Dermoscopy of the hyponychium can be useful in the diagnosis showing twisted coiled vessels. Structural features of nail psoriasis have been described with optical coherence tomography (OCT). Objectives: To investigate vascular features of nail psoriasis using dynamic OCT. Methods: This was an observational, prospective, controlled study in which psoriasis patients with psoriatic nail changes and healthy control patients underwent OCT imaging of the distal nail plate and proximal nail fold. Vertical and horizontal OCT images were analyzed to describe structural and vascular features and to quantify blood flow at depth. Results: Sixteen psoriatic nails and 16 control nails were included. Psoriatic nails had significantly increased blood flow in the proximal nail fold at depths of 0.72 mm (p = 0.035) and 0.76 mm (p = 0.027). Nail thickness was significantly greater in psoriatic nails compared to control nails (p = 0.0016). Compared to control nails, psoriatic nails had dilated, disorganized blood vessels superficially in the proximal nail fold. Limitations: The main limitation of our study is the relatively small sample size. Conclusions: OCT can identify structural and vascular features specific to nail psoriasis.