pdf

MR Neurography Unplugged A Pictorial Essay
Poster No.:
C-0233
Congress:
ECR 2011
Type:
Educational Exhibit
Authors:
R. M. S. V. Vadapalli, M. AK; Hyderabad, AP/IN
Keywords:
Inflammation, Edema, Imaging sequences, Education, MR,
Neuroradiology peripheral nerve
DOI:
10.1594/ecr2011/C-0233
Any information contained in this pdf file is automatically generated from digital material
submitted to EPOS by third parties in the form of scientific presentations. References
to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in
any way constitute or imply ECR's endorsement, sponsorship or recommendation of the
third party, information, product or service. ECR is not responsible for the content of
these pages and does not make any representations regarding the content or accuracy
of material in this file.
As per copyright regulations, any unauthorised use of the material or parts thereof as
well as commercial reproduction or multiple distribution by any traditional or electronically
based reproduction/publication method ist strictly prohibited.
You agree to defend, indemnify, and hold ECR harmless from and against any and all
claims, damages, costs, and expenses, including attorneys' fees, arising from or related
to your use of these pages.
Please note: Links to movies, ppt slideshows and any other multimedia files are not
available in the pdf version of presentations.
www.myESR.org
Page 1 of 54
Learning objectives
1. To high light the MR Imaging prerequisites for peripheral nerve visualization
2. To briefly discuss various established ,cutting edge and new MR neurographic
techniques
3. Role of MRN in Brachial plexus Imaging
4. To discuss the use of MR neurography in Pelvis and high light use of Whole body
Diffusion MR Neurography
5. To illustrate with clinical examples various types of MR neurography in clinical practice
6. To show case various Biomarkers of nerve injury and their use in clinical practice in
extra spinal sciatica, entrapment syndromes,Neoplasms
Background
Types of MR Neurographic techniques
1.Conventional MRI
2.STIR Neurography and Plexography
3.Proset Neurography and Plexography
T.DWIBS MR Neurography (Diffusion Weighted Imaging with background Suppression)
7.DTI fiber tracking
MR Image Finding categories:
-Regions of nerve Hyper Intensity
-Distortions of Normal Nerve course
- Abnormal Nerve contours
-Abnormal Nerve Caliber
Page 2 of 54
Types of brachial Plexus entrapment in thoracic out let syndrome:
1.Linear orientation of plexus with impingement at the lateral border of Scalene triangle
2.Restrictive fibrosis and Plexopathy at the lateral border of Scalene triangle
3.Short, Long ,multifocal areas of nerve hyper intensity edema with Plexopathy
4.C5 Nerve impingement Just proximal to Scalene triangle
5.Fibrous band causing sharp downward distortion of mid and lower trunk proximal
to scalene triangle, with second sharp upward distortion of lower trunk near scalene
insertion at the first rib.
6. Moderate restrictive impingement of the plexus at scalene triangle with short segment
of focal intra substance hyper intensity.
7.Multiple brachial plexus element impingement points with distortion with edema and
hyper intensity(Prof Aaron G.Filler et al)
MR Neurography Visualization:
Long axis and nerve Perpendicular Images
3D MPR/3D MIP
3D Volume rendered Images
Post contrast fat sat T1 coronal
DTI fiber tracking with feactional anisotropy Maps
Diffusion Neurography with ADC maps
MR Neurography in pelvis:
Lower extremity radiculopathies
Impingements at spinal foramina
Page 3 of 54
Distal foramen and extra foraminal Impingements my lateral marginal osteophytes
Lumbo sacral Plexus
Medial aspect of pyriformis muscle
At the ischial margin
At the tendon of obturator internus
At distal ischial tunnel at lateral aspect of ischial tuberosity
Biomarkers of nerve injury:
Morphology
Nerve edema
ADC values
Fractional anisotropy values
Imaging findings OR Procedure details
Page 4 of 54
Fig.: CIDP Brachial Plexo neuropathy
References: R. M. S. V. Vadapalli; chippendale apts- 1-7-12 near Golconda cross
roads, flat 202, Hyderabad, INDIA
MR neurography pre requisites are discussed -STIR Neurography, PROSET
neurography, DWIBS(diffusion Neurography),DTI and fibertracking techniques will be
high lighted -Role of MRN in Pelvis and Brachial plexus is discussed (MR Plexography) Biomarkers like ADC, FA and their calculation in normal and abnormal nerves is illustrated
-Fusion MR neurography with MR PET+DWIBS is show cased -The concept of Whole
body neuro graphy is discussed -True nerve Imaging protocol is Emphasized
Auto Immune Poly neuropathies
CIDP(chronic inflammatory demyelinating polyneuropathy)
The symptoms and signs of CIDP may be asymmetrical
initially and have ascending involvements.
progresses slowly to symmetric weakness, loss of deep
Page 5 of 54
tendon reflex, and impaired sensation in hands and
feet.
Antecedent infections can be identified far less
regularly in patients with CIDP than those with acute
inflammatory demyelinating polyneuropathy (AIDP).
Elevated concentration of CSF protein and evidence of
demyelination on electrodiagnostic examination are
found in most patients with CIDP. The pathophysiology
of CIDP is still unclear, but an autoimmune mechanism
is proposed due to the likely responsiveness of
immune modulating treatments of CIDP.The
efficacy of corticosteroids plasma exchange and IVIg
MMN (multifocal motor neuropathy)
In contrast to CIDP, multifocal motor neuropathy
(MMN) shows an asymmetrical weakness and muscle
atrophy, typically in the distribution of individual peripheral
nerves without sensory involvement.
MMN
with a clinical picture of mononeuritis multiplex and
electrophysiologic evidence of persistent motor conduction
block (MCB) is considered an acquired
immune-mediated demyelinating motor polyneuropathy.
The diagnosis of MMN usually relies on the
presence of MCBs. High titers of anti-GM1 antibodies
are often detected in the serum of patients with
Page 6 of 54
MMN.IVIg and cyclophosphamide are
effective treatment for the majority of patients with
MMN.
The major features that separate MADSAM neuropathy from
typical CIDP are the electrophysiological findings and
favorable responses to plasma exchange, prednisone, or
IVIg. Similar to CIDP, CSF protein content is increased
in 60-80% of patients with MADSAM neuropathy.
On the other hand, polyclonal IgM antibodies against
GM1 may be detected in 40-80% of MMN patients, but
difficult to detect in CIDP and MADSAM neuropathy
MADSAM Neuropathy
Multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy is
characterized
by an asymmetric multifocal pattern of motor and sensory loss, and conduction block and
other features of
demyelination in nerve conduction studies. MADSAM neuropathy needs to be
differentiated from chronic
inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy
(MMN).
In classic CIDP, there are symmetric proximal and distal weakness, sensory deficit in both
upper and lower extremities and reduced deep tendon reflex(2). In MMN, limb weakness
without sensory loss is asymmetric in the distribution of individual peripheral nerves
and the weakness typically begins in the distal upper extremities. It is very important to
distinguish between CIDP, MADSAM neuropathy, and MMN by clinical, laboratory, and
histological features because of different effective therapeutic strategies.
EMNG findings of CIDP,MMN,MADSAM
Page 7 of 54
In MADSAM neuropathy, MMN, and CIDP, the
nerve conduction studies show features of demyelination,
such as conduction block, temporal dispersion, prolonged
distal latencies, slow conduction velocities, and
absent or prolonged F-wave latencies in one or more
motor nerves .MADSAM neuropathy is different from
MMN due to sensory nerves are involved and different
from CIDP due to conspicuous asymmetric multiple
nerves involvement.
Images for this section:
Page 8 of 54
Fig. 1: Prerequisites of an Optimal MR Neurography
Fig. 2: Nerve Imaging Techniques
Page 9 of 54
Fig. 3: Pyriformis and Sciatic Nerve Topographic Anatomy
Page 10 of 54
Fig. 4: carcinoma of cervix with Post Radiation Lumbosacral plexopathy with Sciatic
nerve entrapment
Page 11 of 54
Fig. 5: Lumbosacral trunk: Normal and in Neurofibromatosis(Plexiform)
Page 12 of 54
Fig. 6: Metastatic Adenocarcinoma(Pancreatic) infiltrating the lumbosacral plexus on left
Page 13 of 54
Fig. 7: Extra Pelvic Sciatic neuritis with Nerve Edema
Page 14 of 54
Fig. 8: Pyriformis Syndrome
Page 15 of 54
Fig. 9: Sacro Iliac Tuberculosis with exudate compressing the lumbosacral plexus
Page 16 of 54
Fig. 10: Pelvic dermoid with extrinsic compression on Lumbo Sacral trunk on right
Page 17 of 54
Fig. 11: PROSET MR neurography
Page 18 of 54
Fig. 12: Invasive left Ovarian Tumor at greater Sciatic Notch with mass effect on Sciatic
Nerve
Page 19 of 54
Fig. 13: Neurofibromas of Lumbo Sacral Plexus
Page 20 of 54
Fig. 14: Neurofibromatosis: Multiple neurogenic tumors involving lumbo Sacral Plexus
Page 21 of 54
Fig. 15: Endometriosis with hemorrhagic cysts with mass effect on right lumbosacral
trunk at greater sciatic Foramen
Page 22 of 54
Fig. 16: Right Ovarian Lymphoma B cell with mass effect and entrapment of sciatic nerve
at greater sciatic foramen
Page 23 of 54
Fig. 17: DWIBS MR Neurography
Page 24 of 54
Fig. 18: Fiber tracking of LS plexus
Page 25 of 54
Fig. 19: FA MAps
Page 26 of 54
Fig. 20: Fibertrracking of Sciatic nerve
Page 27 of 54
Fig. 21: Tumor nerve interfaces
Page 28 of 54
Fig. 22: Aggressive GCT invading sacral Plexus
Page 29 of 54
Fig. 23: DTI Fibertracking of Sciatic nerve:Pyriformis segment
Page 30 of 54
Fig. 24: Fiber tracking by DTI in Lumbosacral Plexus
Page 31 of 54
Fig. 25: Thoracic Outlet SYndrome
Page 32 of 54
Fig. 26: STIR Brachial Plexography
Page 33 of 54
Fig. 27: Fiber tracking of LS plexus
Page 34 of 54
Fig. 28: Conclusion
Page 35 of 54
Fig. 29: Brachial plexo and poly neuropathy: Sarcoid
Page 36 of 54
Fig. 30: Right sided brachial plexopathy : sarcoid (inflammatory)
Page 37 of 54
Fig. 31: Right sided brachial plexopathy : sarcoid (inflammatory)
Page 38 of 54
Fig. 32: Lumbar plexopathy :Sarcoid
Page 39 of 54
Fig. 33: Lumbar plexo and poly neuropathy: Sarcoid
Page 40 of 54
Fig. 34: Sarcoid :Inflammatory Plexo Poly Neuropathy Significant Enhancement of nerve
roots on post contrast fat sat T1
Page 41 of 54
Fig. 35: Sarcoid :Inflammatory Plexo Poly Neuropathy Significant Enhancement of nerve
roots on post contrast fat sat T1
Page 42 of 54
Fig. 36: Sarcoid :Inflammatory Plexo Poly Neuropathy
Page 43 of 54
Fig. 37: Multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy
is characterized by an asymmetric multifocal pattern of motor and sensory loss, and
conduction block and other features of demyelination in nerve conduction studies.
MADSAM neuropathy needs to be differentiated from chronic inflammatory demyelinating
polyneuropathy (CIDP) and multifocal motor neuropathy (MMN).
Page 44 of 54
Fig. 38: Multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy
is characterized by an asymmetric multifocal pattern of motor and sensory loss, and
conduction block and other features of demyelination in nerve conduction studies.
MADSAM neuropathy needs to be differentiated from chronic inflammatory demyelinating
polyneuropathy (CIDP) and multifocal motor neuropathy (MMN).
Page 45 of 54
Fig. 39: Multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy
is characterized by an asymmetric multifocal pattern of motor and sensory loss, and
conduction block and other features of demyelination in nerve conduction studies.
MADSAM neuropathy needs to be differentiated from chronic inflammatory demyelinating
polyneuropathy (CIDP) and multifocal motor neuropathy (MMN).
Page 46 of 54
Fig. 40: Multifocal acquired demyelinating sensory and motor (MADSAM) neuropathy
is characterized by an asymmetric multifocal pattern of motor and sensory loss, and
conduction block and other features of demyelination in nerve conduction studies.
MADSAM neuropathy needs to be differentiated from chronic inflammatory demyelinating
polyneuropathy (CIDP) and multifocal motor neuropathy (MMN).
Page 47 of 54
Fig. 41: CIDP Brachial Plexo neuropathy
Page 48 of 54
Fig. 42: 3D MIP of MR neurography of Lumbar plexus in CIDP Note the zsymmetric
thickening of Pre and Post ganglionic segments of the Spial nerves
Page 49 of 54
Fig. 43: CIDP MR Neuro plexography
Page 50 of 54
Fig. 44: CIDP
Page 51 of 54
Fig. 45: CIDP :Lumbosacral plexopathy with L5/S1 nerve root Neuropathy with sciatic
neuritis
Page 52 of 54
Conclusion
MR neurography is a rapidly evolving Technique for peripheral nerve visualization
with Anatomical , functional Imaging capabilities and disease characterization with
Biomarkers to evaluate the therapy response
Personal Information
Rammohan Vadapalli
MD
Consultant radiologist
Vijaya Diagnostics and research
Hyderabad
Andhra pradesh
India
References
1.Filler AG, Kliot M, Howe FA, et al. Application of magnetic resonance neurography
in the evaluation of patients with peripheral nerve pathology. J Neurosurg
1996;85:299-309[Medline]
2.Maravilla K, Aagaard B, Kliot M. MR neurography: MR imaging of peripheral nerves.
Magn Reson Imaging Clin N Am 1998;6:179-194[Medline]
Filler AG, Howe FA, Hayes CE, et al. Magnetic resonance neurography. Lancet
1993;341:659-661[Medline]
3.Kuntz C IV, Blake L, Britz G, et al. Magnetic resonance neurography of peripheral nerve
lesions in the lower extremity. Neurosurgery 1996;39:750-757[Medline]
Page 53 of 54
4.Grant GA, Goodkin R, Kliot M. Evaluation and surgical management of peripheral nerve
problems. Neurosurgery 1999;44:825-840[Medline]
5.Maravilla KR, Bowen BC. Imaging of the peripheral nervous system:
evaluation of peripheral neuropathy and plexopathy. AJNR Am J Neuroradiol
1998;19:1011-6.1023[Medline]
6.Pick T, Howden R, eds. Anatomy, Descriptive and Surgical (Gray's Anatomy)..
Philadelphia: Running Press 1974;781-793
7. Diffusion-weighted MR Neurography of the Brachial Plexus: Feasibility Study1
Taro Takahara, MD, PhD, Jeroen Hendrikse, MD, PhD (Radiology 2008;249:653.)
8. Diffusion-weighted whole-body MR imaging with background body signal suppression:
a feasibility study at 3.0 Tesla
Petra Mürtz, Carsten Krautmacher, Frank Träber, Jürgen Gieseke, Hans Schild, Winfried
Willinek
European Radiology, Vol. 17, No. 12. (15 December 2007), pp. 3031-3037.
9.Quencer RM. The next frontier in neuroradiology: imaging the peripheral nervous
system. AJNR Am J Neuroradiol 1998;19:1001-1001.
10.Maravilla KR, Bowen BC. Imaging of the peripheral nervous system: evaluation of
peripheral neuropathy and plexopathy. AJNR Am J Neuroradiol 1998;19:1011-1023.
[Web of Science][Medline]
11.Lewis RA. Chronic inflammatory demyelinating polyneuropathy. Neurol Clin
2007;25:71-87. [CrossRef][Web of Science][Medline]
12.Takahara T, Imai Y, Yamashita T, Yasuda S, Nasu S, Van Cauteren M. Diffusion
weighted whole body imaging with background body signal suppression (DWIBS):
technical improvement using free breathing, STIR and high resolution 3D display. Radiat
Med 2004;22:275-282. [Medline]
Page 54 of 54