Ultrahigh‐frequency ultrasound of fascicles in the median nerve at the wrist

Abstract

Fascicles within the median nerve at the wrist can be readily imaged. Ultrahigh-frequency ultrasound technology may be informative in a variety of disorders affecting the peripheral nervous system. Muscle Nerve 56: 819-822, 2017.

Ultra–high‐frequency ultrasound in patients with spinal muscular atrophy: A retrospective feasibility study

“…In agreement with their findings, the present study has demonstrated the feasibility of UHF ultrasound for visualizing single nerve fascicles in young children with SMA. The counted fascicle numbers of controls in our study were similar to previous descriptions in adults using UHF, histology, or magnetic resonance imaging protocols . Although the mean area of the nerves was about half of that reported in adults, our findings are in line with previous reports of cross‐sectional areas assessed by high‐resolution ultrasonography in children …”

“…Previously, Cartwright et al showed the general feasibility and good interreader reliability of counting fascicles of the median nerve using UHF ultrasound, suggesting the potential of UHF ultrasound as a diagnostic tool or imaging biomarker in several neurological disorders in adults . In agreement with their findings, the present study has demonstrated the feasibility of UHF ultrasound for visualizing single nerve fascicles in young children with SMA.…”

“…Using the contralateral median nerve as an internal control, we found no side differences for fascicle numbers within each participant. Notably, fascicle numbers in the SMA type II patient were similar on both sides, being unaffected by a median artery that was reported to potentially influence both the fascicle count and nerve size/area . The nerve area, however, was smaller on the side where the artery was present (4.420 mm 2 vs 5.976 mm 2 ).…”

“…Ultrasound imaging is well recognized in neuromuscular disorders (NMDs) and holds promise as a diagnostic modality for personalized medicine in rare diseases . Ultra–high‐frequency (UHF) ultrasound enables high‐resolution visualization of peripheral nerves, permitting detection of single nerve fascicles in the median nerves of healthy adults . To investigate the feasibility of UHF ultrasound to display nerve structures in children with NMD, we conducted a retrospective analysis of pediatric patients who presented to our neuropediatric department between May 13 and May 21, 2019.…”

“…The latter were used for further blinded analysis with an open‐source DICOM viewer (Horos version 3.3.5; Nimble Co LLC d/b/a Purview, Annapolis, Maryland). According to Cartwright et al, a cross‐sectional area was drawn within the hyperechoic epineurium and outside of the nerve fascicles. The number of fascicles was counted within the median nerve and fascicle density (number of fascicles/mm 2 ) was calculated.…”