Purpose: The aim of this study was to compare the elasticity of the median nerve (MN) between hemodialysis (HD) patients without carpal tunnel syndrome (CTS) and with CTS, and to evaluate the diagnostic usefulness of the elasticity of the MN in HD-CTS.
Materials and methods: The MN in 22 HD patients without CTS and 49 HD-CTS patients was studied. The cross-sectional area (CSA) and the elasticity of the MN, which was measured as the subcutaneous fat/median nerve (SF/MN) strain ratio, were evaluated.
Results: The mean SF/MN strain ratio in the groups that had received hemodialysis for 0-5, >5-10, and >10-15 years was 1.4 ± 0.28, 1.7 ± 0.18, and 2.0 ± 0.67, respectively. The mean CSA of the MN in the three groups was 9.9 ± 1.30, 11.6 ± 1.61, and 13.4 ± 2.14 mm2, respectively. The presence of CTS was predicted by means of SF/MN strain ratio and CSA cutoff values of 1.8 and 11 mm2, respectively. Both the SF/MN strain ratio and the CSA in the patients with CTS were higher than those in the patients without CTS (P < 0.05). The sensitivity and specificity of the SF/MN strain ratio and CSA of the MN were 75 and 92 % and 79.2 and 84 %, respectively.
Conclusion: Sonoelastography helps to improve the diagnostic accuracy of the ultrasonographic assessment of CTS.
Keywords: Carpal tunnel syndrome; Hemodialysis; Ultrasound; Ultrasound elastography.