Re: value of power Doppler and gray-scale US in the diagnosis of carpal tunnel syndrome: contribution of cross-sectional area just before the tunnel inlet as compared with the cross-sectional area at the tunnel.

Dear Editor:

I recently read your published article entitled "Value of Power Doppler and Gray-Scale US in the Diagnosis of Carpal Tunnel Syndrome: Contribution of Cross-Sectional Area just before the Tunnel Inlet as Compared with the Cross-Sectional Area at the Tunnel" with interest (1). Dr. Akcar's article (1) is very informative in that it described the axial images of the median nerve at three levels: just proximal to the tunnel inlet, at the level of the pisiform bone, and at the level of the hamate bone. Measurements of the cross-sectional area of the median nerves at the different levels have been used as indicators in the diagnosis of carpal tunnel syndrome. Another diagnostic indicator is the increased cross-sectional area at the level of the pisiform bone compared to the level of the distal radius (2).

The measurements of the median nerves and tendons may have been crossed. To avoid this, I would respectfully suggest after placing the probe perpendicular the nerve moving the 2nd and 3rd fingers. This movement is helpful to distinguish the 2nd and 3rd flexor tendons from the nerve (3).