J Neurosurg Volume 125 • September 2016 603 CliNiCal artiCle J Neurosurg 125:603–614, 2016 S ince its frst description for the assessment of recur- rent laryngeal nerve palsy, 30 ultrasound nerve im- aging has become an established technique for the study of peripheral neuropathies. Several clinical studies have recently demonstrated its high sensitivity and speci- fcity and validated its usefulness in the diagnostic and therapeutic process for focal and generalized peripheral neuropathies. 1,4,7,15,19,29 High-resolution ultrasound is a reliable tool for examin- ing both the extraneural and the intraneural morphology of peripheral nerves. It allows evaluation of nerve continu- ity and shape and detection of nerve enlargements, com- abbreviatioNs CMAP = compound muscle action potential; CSA = cross-sectional area; EMG = electromyography; LSD = least significant difference; MUAP = motor unit action potential; SNAP = sensory nerve action potential. submitted May 1, 2015. aCCepted June 18, 2015. iNClude wheN CitiNg Published online January 22, 2016; DOI: 10.3171/2015.6.JNS151001. * Drs. Toia and A. Gagliardo contributed equally to this work. Preoperative evaluation of peripheral nerve injuries: What is the place for ultrasound? *Francesca toia, md, 1 andrea gagliardo, md, phd, 2 salvatore d’ arpa, md, phd, 1 Cesare gagliardo, md, phd, 3 giuseppe gagliardo, md, 2 and adriana Cordova, md 1 1 Plastic and Reconstructive Surgery, Department of Surgical, Oncological, and Oral Sciences, and 3 Section of Radiological Sciences, Department of Biopathology and Medical Biotechnologies, University of Palermo; and 2 “Clinical Course” Neurophysiology Unit, Palermo, Italy obJeCtive The purpose of this study was to evaluate the usefulness of ultrasound in the preoperative workup of pe- ripheral nerve lesions and illustrate how nerve ultrasonography can be integrated in routine clinical and neurophysiologi- cal evaluation and in the management of focal peripheral nerve injuries. The diagnostic role and therapeutic implications of ultrasonography for different neuropathies are described. methods The authors analyzed the use of ultrasound in 119 entrapment, tumoral, posttraumatic, or postsurgical nerve injuries of limbs evaluated in 108 patients during 2013 and 2014. All patients were candidates for surgery, and in all cases the evaluation included clinical examination, electrodiagnostic studies (nerve conduction study and electromyogra- phy), and ultrasound nerve study. Ultrasound was used to explore the nerve fascicular echo-texture, continuity, and surrounding tissues. The maximum cross-sectional area (CSA) and the presence of epineurial hyperechogenicity or intraneural hyper- or hypoechogenicity, of anatomical anomalies, dynamic nerve dislocations, or compressions were recorded. The concordance rate of neurophysiological and ultrasonographic data was analyzed, classifying ultrasound fndings as confrming, contributive, or nonconfrming with respect to electrodiagnostic data. The correlation between maximum nerve CSA and neurophysiological severity degree in entrapment syndromes was statistically analyzed. results Ultrasonography confrmed electrodiagnostic fndings in 36.1% of cases and showed a contributive role in the diagnosis and surgical planning in 53.8% of all cases; the fndings were negative (“nonconfrming”) in only 10.1% of the patients. In 16% of cases, ultrasound was not only contributive, but had a key diagnostic role in the presence of doubtful electrodiagnostic fndings. The contributive role differed according to etiology, being higher for tumors (100%) and for posttraumatic or postsurgical neuropathies (72.2%) than for entrapment neuropathies (43.8%). CoNClusioNs Ultrasound is a powerful, noninvasive tool for the examination of peripheral nerve injuries, and can guide diagnosis of and surgical strategy for focal peripheral nerve injuries. It allows direct visualization of the cause and extent of nerve lesions and fnds its place between electrodiagnostic tests and exploratory surgery. It can provide invalu- able information, such as the presence and extent of a mass, scar compression, or neuromas. The authors recommend it as a complement to routine clinical and neurophysiological evaluation and as the frst-line imaging modality for masses of suspected nerve origin. http://thejns.org/doi/abs/10.3171/2015.6.JNS151001 Key words ultrasound; peripheral nerve; nerve surgery; nerve imaging; electrodiagnosis ©AANS, 2016 Unauthenticated | Downloaded 05/18/22 01:36 AM UTC