Feasibility of Viscosity Imaging and Shear Wave Elastography for Diagnosing Diabetic Peripheral Neuropathy.

OBJECTIVE: To evaluate the diagnostic potential of viscosity (Vi) imaging and shear wave elastography (SWE) of the tibial nerve in diabetic peripheral neuropathy (DPN). MATERIALS AND METHODS: This prospective study enrolled 40 patients with type II diabetes mellitus (T2DM) accompanied by DPN, 40 T2DM patients without DPN, and 40 healthy controls between January 2025 and April 2025. The bilateral tibial nerves were examined using SWE and Vi imaging to measure shear wave speed (Cs, m/s) and Vi (Pa·s). The reference standards for the DPN diagnosis comprised clinical examination, electromyography, and quantitative sensory testing. Diagnostic performance was assessed using receiver operating characteristic curve analysis and by calculating sensitivity and specificity at the optimal cutoff values for Cs and Vi. The areas under the curve (AUCs) were compared using DeLong's test. RESULTS: On the right side, the DPN group exhibited significantly higher Csmean (median: 4.05 m/s [interquartile range: 3.30-4.51] vs. 3.25 m/s [2.95-3.45]; P < 0.05) and Vimean (median: 3.51 Pa·s [2.70-4.58] vs. 2.43 Pa·s [2.20-2.97]; P < 0.05) compared to the non-DPN group, with similar trends observed on the left side. Both Csmean (AUC = 0.826 [95% confidence interval: 0.725-0.902]) and Vimean (AUC = 0.765 [0.657-0.852]) demonstrated favorable diagnostic performance for DPN, without a significant difference (P = 0.144). Combining Csmean and Vimean resulted in a sensitivity of 62.5% (25/40), a specificity of 95.0% (38/40), and an AUC of 0.828 (0.727-0.903), without significant improvement compared to Csmean or Vimean alone (P = 0.573 and 0.148, respectively). CONCLUSION: Vi imaging quantifies nerve Vi in DPN and offers a novel, non-invasive diagnostic approach to distinguish patients with DPN from those without the condition. However, viscoelastic imaging does not provide greater diagnostic value than SWE.