European Radiology

, Volume 25, Issue 5, pp 1497–1503 | Cite as

Diagnostic Signs of Motor Neuropathy in MR Neurography: Nerve Lesions and Muscle Denervation

  • Daniel Schwarz
  • Markus Weiler
  • Mirko Pham
  • Sabine Heiland
  • Martin Bendszus
  • Philipp Bäumer



To investigate the diagnostic contribution of T2-w nerve lesions and of muscle denervation in peripheral motor neuropathies by magnetic resonance neurography (MRN).


Fifty-one patients with peripheral motor neuropathies underwent high-resolution MRN by large coverage axial T2-w sequences of the upper arm, elbow, and forearm. Images were evaluated by two blinded readers for T2-w signal alterations of median, ulnar, and radial nerves, and for denervation in respective target muscle groups.


All 51 patients displayed nerve lesions in at least one of three nerves, and 43 out of 51 patients showed denervation in at least one target muscle group of these nerves. In 21 out of 51 patients, the number of affected nerves matched the number of affected target muscle groups. In the remaining 30 patients, T2-w lesions were encountered more frequently than target muscle group denervation. In 153 nerve-muscle pairs, 72 showed denervation, but only one had increased muscle signal without a lesion in the corresponding nerve.


MRN-based diagnosis of peripheral motor neuropathies is more likely by visualization of peripheral nerve lesions than by denervation in corresponding target muscles. Increased muscular T2-w signal without concomitant nerve lesions should raise suspicion of an etiology other than peripheral neuropathy.

Key Points

In peripheral neuropathy, T2-w nerve lesions are more frequent than muscle denervation.

Muscle denervation almost never occurs without detectable lesions in corresponding nerves.

MRN-aided diagnosis of peripheral motor neuropathy should focus primarily on nerve lesions.

Increased muscular T2-w signal intensity without concomitant nerve lesions indicates other aetiology.


MR neurography Polyneuropathy MRI Muscle denervation Nerve lesion 



The scientific guarantor of this publication is Dr. med. Philipp Bäumer, Department of Neuroradiology, Heidelberg University Hospital, Germany. The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article. The authors state that this work has not received any funding. No complex statistical methods were necessary for this paper. Institutional Review Board approval was obtained. Written informed consent was obtained from all subjects (patients) in this study. Methodology: prospective, diagnostic study, performed at one institution.

Supplementary material

330_2014_3498_Fig6_ESM.jpg (4.7 mb)
Supplementary Table 1

Clinical data for all patients. Detailed overview of clinical and demographic data of the patient collective. The functional specification of the symptom is followed by the respective MRC grading in brackets. Symptoms are listed in ascending MRC grading order. Muscles are abbreviated as follows: M. brachioradialis (BR), extensor carpi radialis (longus and brevis) (ECR), extensor digitorum communis (EDC), extensor indicis (EI), extensor carpi ulnaris (ECU), pronator teres (PT), flexor carpi ulnaris (FCU), flexor digitorum profundus (FDP), flexor carpi radialis (FCR), pronator quadratus (PQ), flexor pollicis longus (FPL), flexor pollicis brevis (FPB), abductor pollicis brevis (APB), opponens pollicis (OP), abductor digiti minimi (ADM), interosseous dorsalis (IDM). Electrophysiological abbreviations are: motor unit action potential (MUAP), compound muscle action potential (CMAP), sensory nerve action potential (SNAP), distal motor latency (dml), proximal motor latency (pml), sensory evoked potentials (SEP). The following (sixth) column states the corresponding diagnosis, and the seventh column lists the respective interval of time between onset of clinical symptoms and MR neurography. The penultimate column informs about additional MR sequences performed that were not routinely included in the protocol of the study. The last column shows the assigned group of every patient after evaluation of acquired images. At the bottom, the total numbers of male and female patients, the mean age, and the median and mean time delay between onset of clinical symptoms and MR neurography are given. (JPEG 4850 kb)


  1. 1.
    Briani C, Cacciavillani M, Lucchetta M, Cecchin D, Gasparotti R (2013) MR neurography findings in axonal multifocal motor neuropathy. J Neurol 260:2420–2422CrossRefPubMedGoogle Scholar
  2. 2.
    Kikuchi Y, Nakamura T, Takayama S, Horiuchi Y, Toyama Y (2003) MR imaging in the diagnosis of denervated and reinnervated skeletal muscles: experimental study in rats. Radiology 229:861–867CrossRefPubMedGoogle Scholar
  3. 3.
    Polak JF, Jolesz FA, Adams DF (1988) Magnetic resonance imaging of skeletal muscle. Prolongation of T1 and T2 subsequent to denervation. Invest Radiol 23:365–369CrossRefPubMedGoogle Scholar
  4. 4.
    Kim SJ, Hong SH, Jun WS et al (2011) MR imaging mapping of skeletal muscle denervation in entrapment and compressive neuropathies. Radiographics 31:319–332CrossRefPubMedGoogle Scholar
  5. 5.
    Andreisek G, Crook DW, Burg D, Marincek B, Weishaupt D (2006) Peripheral neuropathies of the median, radial, and ulnar nerves: MR imaging features. Radiographics 26:1267–1287CrossRefPubMedGoogle Scholar
  6. 6.
    Yamabe E, Nakamura T, Oshio K, Kikuchi Y, Ikegami H, Toyama Y (2008) Peripheral nerve injury: diagnosis with MR imaging of denervated skeletal muscle —experimental study in rats. Radiology 247:409–417CrossRefPubMedGoogle Scholar
  7. 7.
    Lisle DA, Johnstone SA (2007) Usefulness of muscle denervation as an MRI sign of peripheral nerve pathology. Australas Radiol 51:516–526CrossRefPubMedGoogle Scholar
  8. 8.
    Thawait SK, Chaudhry V, Thawait GK et al (2011) High-resolution MR neurography of diffuse peripheral nerve lesions. Am J Neuroradiol 32:1365–1372CrossRefPubMedGoogle Scholar
  9. 9.
    Stoll G, Bendszus M, Perez J, Pham M (2009) Magnetic resonance imaging of the peripheral nervous system. J Neurol 256:1043–1051CrossRefPubMedGoogle Scholar
  10. 10.
    Andreisek G, Burg D, Studer A, Weishaupt D (2008) Upper extremity peripheral neuropathies: role and impact of MR imaging on patient management. Eur Radiol 18:1953–1961CrossRefPubMedGoogle Scholar
  11. 11.
    Bendszus M, Stoll G (2005) Technology insight: visualizing peripheral nerve injury using MRI. Nat Clin Pract Neurol 1:45–53CrossRefPubMedGoogle Scholar
  12. 12.
    Koltzenburg M, Bendszus M (2004) Imaging of peripheral nerve lesions. Curr Opin Neurol 17:621–626CrossRefPubMedGoogle Scholar
  13. 13.
    Baumer P, Mautner VF, Baumer T et al (2013) Accumulation of non-compressive fascicular lesions underlies NF2 polyneuropathy. J Neurol 260:38–46CrossRefPubMedGoogle Scholar
  14. 14.
    Bäumer P, Dombert T, Staub F, Kaestel T, Bartsch AJ, Heiland S, Bendszus M, Pham M (2011) Ulnar neuropathy at the elbow MR neurography–nerve T2 signal increase and caliber. Radiology 260Google Scholar
  15. 15.
    Pham M, Oikonomou D, Baumer P et al (2011) Proximal neuropathic lesions in distal symmetric diabetic polyneuropathy: findings of high-resolution magnetic resonance neurography. Diabetes Care 34:721–723CrossRefPubMedCentralPubMedGoogle Scholar
  16. 16.
    Pham M, Baumer P, Meinck HM et al (2014) Anterior interosseous nerve syndrome: fascicular motor lesions of median nerve trunk. Neurology 82:598–606CrossRefPubMedCentralPubMedGoogle Scholar
  17. 17.
    Baumer P, Weiler M, Ruetters M et al (2012) MR neurography in ulnar neuropathy as surrogate parameter for the presence of disseminated neuropathy. PLoS One 7:e49742CrossRefPubMedCentralPubMedGoogle Scholar
  18. 18.
    Vucic S, Black K, Chong PS, Cros D (2007) Multifocal motor neuropathy with conduction block: distribution of demyelination and axonal degeneration. Clin Neurophysiol 118:124–130CrossRefPubMedGoogle Scholar
  19. 19.
    Suarez GA (2005) Chapter 102 - Immune Brachial Plexus Neuropathy. In: Dyck PJ, Thomas PK (eds) Peripheral Neuropathy (Fourth Edition). W.B. Saunders, Philadelphia, pp 2299–2308CrossRefGoogle Scholar
  20. 20.
    Wilbourn AJ, Aminoff MJ (1998) AAEM minimonograph 32: the electrodiagnostic examination in patients with radiculopathies. Muscle Nerve 21:1612–1631CrossRefPubMedGoogle Scholar
  21. 21.
    Aminoff MJ, Goodin DS, Parry GJ, Barbaro NM, Weinstein PR, Rosenblum ML (1985) Electrophysiologic evaluation of lumbosacral radiculopathies: electromyography, late responses and somatosensory evoked potentials. Neurology 35:1514–1518CrossRefPubMedGoogle Scholar
  22. 22.
    McDonald CM, Carter GT, Fritz RC, Anderson MW, Abresch RT, Kilmer DD (2000) Magnetic resonance imaging of denervated muscle: comparison to electromyography. Muscle Nerve 23:1431–1434CrossRefPubMedGoogle Scholar
  23. 23.
    Kastel T, Heiland S, Baumer P, Bartsch AJ, Bendszus M, Pham M (2011) Magic angle effect: a relevant artifact in MR neurography at 3 T? AJNR Am J Neuroradiol 32:821–827CrossRefPubMedGoogle Scholar
  24. 24.
    Ferdinand BD, Rosenberg ZS, Schweitzer ME et al (2006) MR imaging features of radial tunnel syndrome: initial experience. Radiology 240:161–168CrossRefPubMedGoogle Scholar
  25. 25.
    England JD, Asbury AK (2004) Peripheral neuropathy. Lancet 363:2151–2161CrossRefPubMedGoogle Scholar
  26. 26.
    Viddeleer AR, Sijens PE, van Ooyen PM, Kuypers PD, Hovius SE, Oudkerk M (2012) Sequential MR imaging of denervated and reinnervated skeletal muscle as correlated to functional outcome. Radiology 264:522–530CrossRefPubMedGoogle Scholar
  27. 27.
    Deroide N, Bousson V, Daguet E et al (2012) Muscle magnetic resonance imaging sensitivity does not decrease in chronic, mild, or proximal lower limb neuropathies. Muscle Nerve 45:659–667CrossRefPubMedGoogle Scholar
  28. 28.
    Viallon M, Vargas MI, Jlassi H, Lovblad KO, Delavelle J (2008) High-resolution and functional magnetic resonance imaging of the brachial plexus using an isotropic 3D T2 STIR (Short Term Inversion Recovery) SPACE sequence and diffusion tensor imaging. Eur Radiol 18:1018–1023CrossRefPubMedGoogle Scholar

Copyright information

© European Society of Radiology 2014

Authors and Affiliations

  • Daniel Schwarz
    • 1
  • Markus Weiler
    • 2
    • 3
  • Mirko Pham
    • 1
  • Sabine Heiland
    • 4
  • Martin Bendszus
    • 1
  • Philipp Bäumer
    • 1
  1. 1.Department of NeuroradiologyHeidelberg University HospitalHeidelbergGermany
  2. 2.Department of NeurologyHeidelberg University HospitalHeidelbergGermany
  3. 3.Clinical Cooperation Unit NeurooncologyGerman Cancer Research Center (DKFZ)HeidelbergGermany
  4. 4.Section of Experimental Radiology, Department of NeuroradiologyHeidelberg University HospitalHeidelbergGermany

Personalised recommendations