Utility of shear wave elastography and high-definition color for diagnosing carpal tunnel syndrome.

• Shear wave elastography (SWE) and high-definition (HD) color provide useful supportive information for the evaluation of carpal tunnel syndrome (CTS). • SWE discriminated CTS severity, and detected CTS patients with normal nerve conduction study results. • 50.12-kPa for median nerve (MN) stiffness at the wrist and 1.91 for the MN stiffness ratio are cutoff values for CTS diagnosis. The diagnostic values of measuring median nerve (MN) stiffness and vascularity with shear wave elastography (SWE) and high-definition (HD) color were investigated in carpal tunnel syndrome (CTS). Seventy patients (123 wrists) with CTS and thirty-five healthy volunteers (70 wrists) were enrolled. Based on nerve conduction studies (NCS), the patients were subdivided into NCS-negative, mild-to-moderate, and severe CTS groups. MN and abductor pollicis brevis (APB) SWE and MN HD color were performed on a longitudinal plane. The mild-to-moderate and severe CTS groups showed increased MN stiffness at the wrist and MN stiffness ratio (wrist-to forearm) compared with the control (p < 0.001). The NCS-negative CTS group showed increased MN stiffness at the wrist (p = 0.022) and MN stiffness ratio (p = 0.032) compared with the control. The severe CTS group showed increased MN stiffness at the wrist compared with the mild-to-moderate CTS group (p = 0.034). The cutoff-values in diagnosing NCS-confirmed CTS were 50.12 kPa for MN stiffness at the wrist, 1.91 for MN stiffness ratio, and grade 1 for HD color. SWE and HD color are good supportive tools in diagnosing and assessing severity in CTS. SWE and HD color demonstrated that MN in CTS was associated with increased stiffness and hypervascularity. [ABSTRACT FROM AUTHOR]