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

To evaluate the diagnostic potential of viscosity (Vi) imaging and shear wave elastography (SWE) of the tibial nerve in diabetic peripheral neuropathy (DPN).

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.

On the right side, the DPN group exhibited significantly higher Cs_mean (median: 4.05 m/s [interquartile range: 3.30-4.51] vs. 3.25 m/s [2.95-3.45]; P < 0.05) and Vi_mean (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 Cs_mean (AUC = 0.826 [95% confidence interval: 0.725-0.902]) and Vi_mean (AUC = 0.765 [0.657-0.852]) demonstrated favorable diagnostic performance for DPN, without a significant difference (P = 0.144). Combining Cs_mean and Vi_mean 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 Cs_mean or Vi_mean alone (P = 0.573 and 0.148, respectively).

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.