A computerized system of nail-fold capillaroscopy for dry eye disease diagnosis

Nail-fold Capillaroscopy is a convenient and non-invasive tool to evaluate peripheral circulation. Rheumatic diseases such as Raynaud's disease and systemic sclerosis are investigated mostly by nail-fold capillaroscopy. However, it has not been used popularly due to the lack of golden standard in both measurement procedure and objective quantity analysis. This study proposes a computerized system of nail-fold capillaroscopy (CNC). CNC includes standard measurement procedures and three criterions of microcirculation which are capillary density, capillary width and blood flow velocity. CNC is applied to the images of 36 normal subjects and seven patients of dry eye disease (DED). We found density and width of afferent capillary were the better parameters to identify DED (p < 0.05). CNC could be a good auxiliary diagnostic tool for DED.