Background Carpal tunnel syndrome (CTS) is the most common form of peripheral entrapment neuropathies. Ultrasonography (US) has been used to diagnose CTS with a good sensitivity and specificity.There is no consensus about the role of colour Doppler US in diagnosis of CTS (1).

Objectives To assess the diagnostic role of color Doppler ultrasonography in idiopathic CTS.

Methods This study included 2 groups. The first group included 35females middle aged (32.1±4.8) patients with idiopathic CTS. The second group included 35 healthy middle aged (40.1±7.6) females. The diagnosis of CTS was done clinically and by nerve conduction studies.Ultrasonography of the median nerve was performed to find colour Doppler signals, wrist cross sectional area, forearm cross sectional area, flattening ratio, flexor retinaculum bowing and pronator quadratus ratio by use of high frequency (5–12MHz) linear probe diagnostic ultrasound.

Results There was a statistical highly significant difference between control group and patients with CTS regarding colour Doppler signal (p=0.00).the specificity of CDUS in diagnosis of CTS was excellent (100%) but its sensitivity was poor (22.9%) with an accuracy of 61.4%. As regards the other US parameters, flattening ratio was the most accurate method (86.4%) with a senstivity (88.7%) and a specificity of (83.3%).There was a statistical highly significant positive correlation between nerve conduction study grading and Color Doppler ultrasonography (p=0.005).

Conclusions CDUS is a highly specific test in evaluation of idiopathic CTS. It represents a useful confirmatory tool in diagnosis. Flattening ratio is the most accurate grey scale US parameter and highly correlated with CT severity.

1. Akcar N, et al. (2010).Korean Journal of Radiology; 11 (6): 632–639.

Disclosure of Interest None declared