Magnetic Resonance Neurography of Peripheral Nerve Lesions in the Lower Extremity

Object Treatment of spinal and peripheral nerve lesions relies on localization of the pathology by the use of neurological examination, spinal MR imaging and electromyography (EMG)/nerve conduction studies (NCSs). Magnetic resonance neurography (MRN) is a novel imaging technique recently developed for direct imaging of spinal and peripheral nerves. In this study, the authors analyzed the role of MRN in the evaluation of spinal and peripheral nerve lesions. Methods Imaging studies, medical records, and EMG/NCS results were analyzed retrospectively in a consecutive series of 191 patients who underwent MRN for spinal and peripheral nerve disorders at the University of California, San Francisco between March 1999 and February 2005. Ninety-one (47.6%) of these patients also underwent EMG/NCS studies. Results In those who underwent both MRN and EMG/NCS, MRN provided the same or additional diagnostic information 32 and 45% of patients, respectively. Magnetic resonance neurograms were obtained at a median of 12 months after the onset of symptoms. The utility of MRN correlated with the interval between the onset of symptoms to MRN. Twelve patients underwent repeated MRN for serial evaluation. The decrease in abnormal signal detected on subsequent MRN correlated with time from onset of symptoms and the time interval between MRN, but not with resolution of symptoms. Twenty-one patients underwent MRN postoperatively to assess persistent, recurrent, or new symptoms; of these 3 (14.3%) required a subsequent surgery. Conclusions Magnetic resonance neurography is a valuable adjunct to conventional MR imaging and EMG/NCS in the evaluation and localization of nerve root, brachial plexus, and peripheral nerve lesions. The authors found that MRN is indicated in patients: 1) in whom EMG and traditional MR imaging are inconclusive; 2) who present with brachial plexopathy who have previously received radiation therapy to the brachial plexus region; 3) who present with brachial plexopathy and have systemic tumors; and 4) in patients under consideration for surgery for peripheral nerve lesions or after trauma. Magnetic resonance neurography is limited by the size of the nerve trunk imaged and the timing of the study.

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Fascicular Ratio Pilot Study: High-Resolution Neurosonography—A Possible Tool for Quantitative Assessment of Traumatic Peripheral Nerve Lesions Before and After Nerve Surgery

Neurosurgery ◽

10.1093/neuros/nyy355 ◽

2018 ◽

Vol 85 (3) ◽

pp. 415-422 ◽

Cited By ~ 5

Author(s):

Christian Heinen ◽

Patrick Dömer ◽

Thomas Schmidt ◽

Bettina Kewitz ◽

Ulrike Janssen-Bienhold ◽

...

Keyword(s):

High Resolution ◽

Peripheral Nerve ◽

Quantitative Assessment ◽

Control Group ◽

Structural Reorganization ◽

Magnetic Resonance Neurography ◽

Nerve Lesions ◽

Peripheral Nerve Lesions ◽

Significant Difference ◽

Nerve Surgery

Abstract BACKGROUND Clinical and electrophysiological assessments prevail in evaluation of traumatic nerve lesions and their regeneration following nerve surgery in humans. Recently, high-resolution neurosonography (HRNS) and magnetic resonance neurography have gained significant importance in peripheral nerve imaging. The use of the grey-scale-based “fascicular ratio” (FR) was established using both modalities allowing for quantitative assessment. OBJECTIVE To find out whether FR using HRNS can assess nerve trauma and structural reorganization in correlation to postoperative clinical development. METHODS Retrospectively, 16 patients with operated traumatic peripheral nerve lesions were included. The control group consisted of 6 healthy volunteers. All imaging was performed with a 15 to 6 MHz ultrasound probe (SonoSite X-Porte; Fujifilm, Tokyo, Japan). FR was calculated using Fiji (兠) on 8-bit-images (“MaxEntropy” using “Auto-Threshold” plug-in). RESULTS Thirteen of 16 patients required autologous nerve grafting and 3 of 16 extra-intraneural neurolysis. There was no statistical difference between the FR of nonaffected patients’ nerve portion with 43.48% and controls with FR 48.12%. The neuromatous nerve portion in grafted patients differed significantly with 85.05%. Postoperatively, FR values returned to normal with a mean of 39.33%. In the neurolyzed patients, FR in the affected portion was 78.54%. After neurolysis, FR returned to healthy values (50.79%). Ten of 16 patients showed clinical reinnervation. CONCLUSION To our best knowledge, this is the first description of FR using HRNS for quantitative assessment of nerve damage and postoperative structural reorganization. Our results show a significant difference in healthy vs lesioned nerves and a change in recovering nerve portions towards a more “physiological” ratio. Further evaluation in larger patient groups is required.

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Peripheral Nerve Lesions Secondary to Varicose Vein Surgery of the Lower Extremity: Review of the Literature

Damar Cerrahi Dergisi ◽

10.9739/uvcd.2012-32117 ◽

2012 ◽

Vol 21 (3) ◽

pp. 276-284

Author(s):

HÜSEYİN İLKER İPEKDAL

Keyword(s):

Lower Extremity ◽

Peripheral Nerve ◽

Varicose Vein ◽

Review Of The Literature ◽

Varicose Vein Surgery ◽

Nerve Lesions ◽

Peripheral Nerve Lesions

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Peripheral nervous system alterations in infant and adult neurofibromatosis type 2

Neurology ◽

10.1212/wnl.0000000000007898 ◽

2019 ◽

Vol 93 (6) ◽

pp. e590-e598 ◽

Cited By ~ 2

Author(s):

Tim Godel ◽

Philipp Bäumer ◽

Said Farschtschi ◽

Isabel Gugel ◽

Moritz Kronlage ◽

...

Keyword(s):

Peripheral Nerve ◽

Dorsal Root Ganglia ◽

Dorsal Root ◽

Neurofibromatosis Type ◽

Neurofibromatosis Type 2 ◽

Healthy Controls ◽

Magnetic Resonance Neurography ◽

Nerve Lesions ◽

Peripheral Nerve Lesions

ObjectiveTo examine the involvement of dorsal root ganglia and peripheral nerves in children with neurofibromatosis type 2 compared to healthy controls and symptomatic adults by in vivo high-resolution magnetic resonance neurography.MethodsIn this prospective multicenter study, the lumbosacral dorsal root ganglia and sciatic, tibial, and peroneal nerves were examined in 9 polyneuropathy-negative children diagnosed with neurofibromatosis type 2 by a standardized magnetic resonance neurography protocol at 3T. Volumes of dorsal root ganglia L3 to S2 and peripheral nerve lesions were assessed and compared to those of 29 healthy children. Moreover, dorsal root ganglia volumes and peripheral nerve lesions were compared to those of 14 adults with neurofibromatosis type 2.ResultsCompared to healthy controls, dorsal root ganglia hypertrophy was a consistent finding in children with neurofibromatosis type 2 (L3 +255%, L4 +289%, L5 +250%, S1 +257%, and S2 +218%, p < 0.001) with an excellent diagnostic accuracy. Moreover, peripheral nerve lesions occurred with a high frequency in those children compared to healthy controls (18.89 ± 11.11 vs 0.90 ± 1.08, p < 0.001). Children and adults with neurofibromatosis type 2 showed nonsignificant differences in relative dorsal root ganglia hypertrophy rates (p = 0.85) and peripheral nerve lesions (p = 0.28).ConclusionsAlterations of peripheral nerve segments occur early in the course of neurofibromatosis type 2 and are evident even in children not clinically affected by peripheral polyneuropathy. While those early alterations show similar characteristics compared to adults with neurofibromatosis type 2, the findings of this study suggest that secondary processes might be responsible for the development and severity of associated polyneuropathy.

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Magnetic resonance neurography of the brachial plexus

Indian Journal of Plastic Surgery ◽

10.4103/0970-0358.163045 ◽

2015 ◽

Vol 48 (02) ◽

pp. 129-137 ◽

Cited By ~ 1

Author(s):

Vaishali Upadhyaya ◽

Divya Narain Upadhyaya ◽

Adarsh Kumar ◽

Ashok Kumar Pandey ◽

Ratni Gujral ◽

...

Keyword(s):

Magnetic Resonance ◽

Brachial Plexus ◽

Peripheral Nerves ◽

Imaging Modality ◽

Nerve Tissue ◽

Magnetic Resonance Neurography ◽

Nerve Lesions ◽

Peripheral Nerve Lesions ◽

Magnetic Resonance Imaging Mri

ABSTRACTMagnetic Resonance Imaging (MRI) is being increasingly recognised all over the world as the imaging modality of choice for brachial plexus and peripheral nerve lesions. Recent refinements in MRI protocols have helped in imaging nerve tissue with greater clarity thereby helping in the identification, localisation and classification of nerve lesions with greater confidence than was possible till now. This article on Magnetic Resonance Neurography (MRN) is based on the authors’ experience of imaging the brachial plexus and peripheral nerves using these protocols over the last several years.

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High-resolution ultrasonography in the diagnosis and intraoperative management of peripheral nerve lesions

Journal of Neurosurgery ◽

10.3171/2010.2.jns091324 ◽

2011 ◽

Vol 114 (1) ◽

pp. 206-211 ◽

Cited By ~ 49

Author(s):

Franklin C. Lee ◽

Harminder Singh ◽

Levon N. Nazarian ◽

John K. Ratliff

Keyword(s):

High Resolution ◽

Peripheral Nerve ◽

Imaging Modality ◽

Correct Diagnosis ◽

Clinical History ◽

Magnetic Resonance Neurography ◽

Nerve Lesions ◽

Peripheral Nerve Lesions ◽

Intraoperative Management ◽

High Resolution Ultrasonography

Object The diagnosis of peripheral nerve lesions relies on clinical history, physical examination, electrodiagnostic studies, and radiography. Magnetic resonance neurography offers high-resolution visualization of structural peripheral nerve lesions. The availability of MR neurography may be limited, and the costs can be significant. By comparison, ultrasonography is a portable, dynamic, and economic technology. The authors explored the clinical applicability of high-resolution ultrasonography in the preoperative and intraoperative management of peripheral nerve lesions. Methods The authors completed a retrospective analysis of 13 patients undergoing ultrasonographic evaluation and surgical treatment of nerve lesions at their institution (nerve entrapment [5], trauma [6], and tumor [2]). Ultrasonography was used for diagnostic (12 of 13 cases) and intraoperative management (6 of 13 cases). The authors examine the initial impact of ultrasonography on clinical management. Results Ultrasonography was an effective imaging modality that augmented electrophysiological and other neuroimaging studies. The modality provided immediate visualization of a sutured peroneal nerve after a basal cell excision, prompting urgent surgical exploration. Ultrasonography was used intraoperatively in 2 cases to identify postoperative neuromas after mastectomy, facilitating focused excision. Ultrasonography correctly diagnosed an inflamed lymph node in a patient in whom MR imaging studies had detected a schwannoma, and the modality correctly diagnosed a tendinopathy in another patient referred for ulnar neuropathy. Ultrasonography was used in 6 patients to guide the surgical approach and to aid in intraoperative localization; it was invaluable in localizing the proximal segment of a radial nerve sectioned by a humerus fracture. In all cases, ultrasonography demonstrated the correct lesion diagnosis and location (100%); in 7 (58%) of 12 cases, ultrasonography provided the correct diagnosis when other imaging and electrophysiological studies were inconclusive or inadequate. Conclusions High-resolution ultrasonography may provide an economical and accurate imaging modality with utility in diagnosis and management of peripheral nerve lesions. Further research is required to assess the role of ultrasonography in evaluation of peripheral nerve pathology.

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