The aim of the study was to determine whether there is a correlation between the increased intraneural flow as measured using Doppler ultrasound (US) and superb microvascular imaging (SMI) methods and the severity of CTS as measured by nerve conduction studies. Moreover, investigators investigated the association of increased intraneural flow with the cross sectional area of the median nerve. The null hypothesis that there is no correlation between increased intraneural flow and the severity of carpal tunnel syndrome.