Median Nerve Strain and Shear Wave Elastography in Hypothyroid Patients With Carpal Tunnel Syndrome Symptoms

Objective: This study aimed to evaluate median nerve elasticity using stress elastography (SE) and shear wave elastography (SWE) in hypothyroid patients presenting with symptoms related to carpal tunnel syndrome (CTS). Methods: Twenty-seven hypothyroid patients (54 wrists) with CTS and 28 healthy controls (56 wrists) were prospectively studied. The median nerve cross-sectional area (MCSA) was measured by ultrasonography (US), and nerve stiffness was assessed with SE and SWE. Receiver operating characteristic (ROC) analysis was performed to determine optimal diagnostic cut-off values. Results: MCSA was significantly higher in hypothyroid patients (right: 0.10 ± 0.02 cm²; left: 0.09 ± 0.02 cm²) than in controls (P < 0.001). Type II and III SE elasticity patterns predominated in patients, whereas Type IV was most common in controls. SWE values were higher in the patient group (right/axial: 69.19 ± 36.73 kPa; left/axial: 52.93 ± 26.73 kPa; right/longitudinal: 69.51 ± 32.29 kPa; left/longitudinal: 56.20 ± 23.38 kPa), with significant differences between groups (P < 0.001). ROC analysis identified an optimal MCSA cut-off value of 0.07 cm² for both sides, demonstrating high diagnostic accuracy (right AUC = 0.976; left AUC = 0.960). SWE cut-off values were 33.21 kPa on the right and 29.41 kPa on the left, yielding sensitivities of 92.6% and 85.2% and specificities of 96.4% and 92.9%, respectively. Conclusion: Sonoelastography is a reproducible, noninvasive, and accessible method to assess median nerve biomechanical changes in hypothyroid patients with CTS symptoms.