Study of Microvascular Morphology from Optical Image of Nailfold Capillary using Image Processing Techniques

Nail fold capillary angiography (NFC) is a noninvasive imaging technique used to assess the capillary circulation in the nail fold regions. A disease’s diagnosis and prognosis can be improved by characterizing abnormalities in the microvasculature. Capillary angiography is often performed as the primary indication for patients with suspected microcirculatory disorders such as Raynaud’s phenomenon. In the areas of pathology assessment and treatment planning, microscopic findings of capillaries based on microcirculation studies might be beneficial. Capillary angiography of the nail folds provides an important assessment of clinical practice and research. The presented work focuses on video nail fold capillaroscopy and the image processing approach for measuring the capillary dimensions in the nailfold region. Using image processing algorithms the optimum enhancement filters and segmentation methods are identified to segment the nail fold capillaries. The wiener and bilateral filter are used to enhance the image and further morphological operations are employed to identify and segment the boundaries of the capillaries. The dimensions of the capillary such as the length, width, and the distance between the two loops are measured which can be used for further particular disease analysis.