The Role of 70-MHz Ultrahigh-Frequency Ultrasound in the Peripheral Nerve Injury

Aim: High-frequency ultrasound with an 18-MHz probe (18 MHz-HFUS) plays a relevant role in the evaluation of peripheral nerve injury (PNI). Ultrahigh-frequency ultrasound with a 70-MHz probe (70 MHz-UHFUS) offers higher spatial resolution and could allow a better detection of PNI. This study aimed to compare the diagnostic performance of HFUS and UHFUS in PNI detection.

Materials and methods: In this retrospective study, were selected, between July 2022 and April 2024, 61 patients underwent HFUS, UHFUS, and nerve conduction study (NCS) for clinical suspicion of traumatic forearm PNI. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy of HFUS and UHFUS in PNI detection were calculated and compared. NCS was used as the reference standard. Nonparametric statistical tests were used. A p value of < 0.05 was considered statistically significant.

Results: Comparing the diagnostic performance in PNI detection, the 70 MHz-UHFUS showed a sensitivity and diagnostic accuracy significantly higher than 18 MHz-HFUS, respectively, 98.0% versus 82.4% (p = 0.0205) and 95.1% versus 82.0% (p = 0.0468). Otherwise, not significantly difference were in specificity, PPV, and NPV.

Conclusions: UHFUS compared to HFUS demonstrated a higher sensitivity and diagnostic accuracy in PNI detection.