Assessment of psoriatic plaque in vivo with correlation mapping optical coherence tomography

Background/Purpose: Vascular abnormalities play an acute role in the pathogenesis of psoriasis. In order to characterize vascular involvement in psoriasis and its regular clinical assessment in vivo, non-invasive high speed imaging with high resolution and high sensitivity is needed. Methods: The correlation mapping optical coherence tomography (cmOCT) technique was used for in vivo microcirculation imaging of human forearm under normal and psoriatic conditions. The cmOCT technique developed by our group uses dense scanning OCT image acquisition and post-processing software based on correlation statistics. The frequency domain OCT system was used for imaging which acquires a 3D volume of 1024 × 1024 A-scans, each of 512 pixels deep in approximately 70 s. The cmOCT technique processes the resulting OCT volume within 116 s using a 7 × 7 kernel. Results: 3D structural and functional (microcirculation) maps of the healthy tissue and the psoriatic plaque were obtained using the cmOCT technique. The presented results indicate that cmOCT allows not only the identification of the microvessels, but also produces more detailed microvascular networks showing how the blood vessels relate to each other in healthy tissue and within the plaque. The microcirculation pattern within the plaque is totally different from the healthy tissue. The distinct changes are also observed in vessel density, tortuosity, and orientation. Conclusion: The cmOCT provides high sensitivity and imaging speed for in vivo microcirculation imaging within the human skin under normal and diseased conditions.