August 17, 2019
Francesca Bagnato M.D.Ph.DAssistant Professor of Clinical Neurology
TN Valley Health Care System Nashville Campus & Vanderbilt University Medical Center
Imaging Spinal Cord Hidden Pathology
Paralyzed Veterans of AmericaHealthcare Summit 2019
Orlando FL
DISCLOSURESDr. Bagnato’s Research Lab is funded by the National MS Society (PP-1801-29686 and RG-1901-33190) and the National Institutes of Health (1R01-NS109114-01).
Dr. Bagnato acted a PI for Novartis Pharmaceuticals sponsored phase-IVstudy (Novartis VUMC64211).
Dr. Bagnato received honorary compensations for speaking bureau fromEMD Serono.
LEARNING OBJECTIVESObjective #1: To summarize anatomy and mechanismsof spinal cord disease outside lesions;
Objective #2: To recognize the challenges associatedwith spinal cord imaging;
Objective #3: To describe how imaging can untanglenon-lesional “hidden” spinal cord pathology.
SPINAL CORD ANATOMY (1)33 vertebral bones
https://scireproject.com/community/topic/spinal‐cord‐anatomy/
https://nba.uth.tmc.edu/neuroanatomy/L4/Lab04p01_index.html
SPINAL CORD ANATOMY (2)
https://www.orthobullets.com/spine/2008/incomplete‐spinal‐cord‐injuries
SPINAL CORD PATHOLOGY
The neuropathology of (various) diseases in the spinal cord may be dividedin two broad categories:
primary pathology spinal cord lesions
secondary pathology manifesting as retrograde and anterogradedegeneration of the axon and its cell body.
SPINAL CORD PATHOLOGY
The neuropathology of (various) diseases in the spinal cord may be dividedin two broad categories:
primary pathology spinal cord lesions, and
secondary pathology manifesting as retrograde and anterogradedegeneration of the axon and its cell body.
PRIMARY PATHOLOGY
Polio Multiple Sclerosis ALS
http://medicalhealthguides.blogspot.com
ASA occlusion 3ry Syphilis Syringomyelia Vitamin B12 deficiency
http://medicalhealthguides.blogspot.com
PRIMARY PATHOLOGY
From Freund et al. Lancet Neurology 2019
PRIMARY PATHOLOGY
Our virtues and our failings are inseparable, like force and matter. When they separate, man is no more…Nikole Tesla
Interstellar space 10^-10 Tesla 10^-6 Gauss
Earth's magnetic field 0.00005 Tesla 0.5 Gauss
Small bar magnet 0.01 Tesla 100 Gauss
Within a sunspot 0.15 Tesla 1500 Gauss
Big electromagnet 1.5 Tesla 15,000 Gauss
Strong lab magnet 10 Tesla 100,000 Gauss
Surface of neutron star 100,000,000 Tesla 10^12 Gauss
Magstar 100,000,000,000 Tesla 10^15 Gauss
1 Tesla = 65,000 magnetic field lines per square inch 7 Tesla = 70,000 times the earth’s magnetic field
CHALLENGES IN SPINAL CORD IMAGING
1. SMALL
2. CLOSE TO MOVING ORGANS
3. CLOSE TO STRCTURES WIT DIFFERENT CONTRAST
VISUALIZING LESIONS USING MRI
Conventional MRI plays a crucial role in the diagnostic workup of spinalcord pathology as it shows intrinsic lesions and extrinsic compression ofthe spinal cord.
Conventional MRI includes T2-weighted sequences, STIR (short-TIInversion Recovery) and T1-weighted sequences obtained after the injectionof the contrast agent Gadolinium.
Freund et al. Lancet neurology 2019
Modified rom Freund et al. Lancet Neurology 2019
Neurosarcoidosis: Radiological Manifestations (5) FIGURE 4.
NEUROSARCOIDOSIS
MULTIPLE SCLEROSIS AND NMO
From Moccia et al. Ther. Adv Neurol. Disord. 2019
STIR ARTIFACTS
http://mriquestions.com/gibbs‐artifact.html
SPINAL CORD PATHOLOGY
The neuropathology of (various) diseases in the spinal cord may be dividedin two broad categories:
primary pathology spinal cord lesions, and
secondary pathology manifesting as retrograde and anterogradedegeneration of the axon and its cell body.
From Freund et al. Lancet Neurology 2019
Spinal Cord Hidden Pathology
Degeneration
Distal to the injury (Wallerian)
Dying back or retrograde
PRIMARY PATHOLOGY
Polio Multiple Sclerosis ALS
http://medicalhealthguides.blogspot.com
Imaging Spinal Cord Hidden Pathology
Spinal Cord Atrophy (1)Spinal cord atrophy is generally measured as the cross-sectional area atthe cervical level.
Moccia et al. Ther. Adv Neurol. Disord. 2019
Spinal Cord Atrophy Measurements
Weeda et al. Neuroimage Clin 2019
axial slices starting from the most superior point of C1 and ending at a position 30 mm more inferior.
Winston Ann Neurol 2014
Winston Ann Neurol 2014
From Freund et al. Lancet Neurology 2019
Spinal Cord Hidden Pathology
Magnetization transfer imaging SWI Diffusion Tensor Imaging
MTI is a quantitative technique that measures themagnetization exchange between freely mobileprotons and those associated withmacromolecules such as myelin or axonalmembranes MT ratio or MTR
Magnetization Transfer Imaging (MTI)
http://mriquestions.com/magnetization‐transfer1.html
Magnetization Transfer Imaging (MTI)
http://mriquestions.com/magnetization‐transfer1.html
MTR ~0.4
Magnetization Transfer Imaging (MTI)
http://mriquestions.com/magnetization‐transfer1.html
MTR ~0.4
MTR ~0.2
Magnetization Transfer Imaging (MTI)
From Martin et al. PLOS‐one 2018
From Oh J et al. Neurology 2015
Diffusion Tensor Imaging (MTI)
https://mrgranato.wordpress.com/2018/09/28/osmosis-diffusion-homework-article-sept-28/
Diffusion Tensor Imaging (DTI)
http://mriquestions.com/magnetization‐transfer1.html
Diffusion Tensor Imaging (DTI)
http://mriquestions.com/magnetization‐transfer1.html
Radial diffusivity
Axial Diffusivity
Diagonal Diffusivity
(R+A+D)/3 Mean Diffusivity
Diffusion Tensor Imaging (DTI)
http://mriquestions.com/magnetization‐transfer1.html
Diffusion Tensor Imaging (DTI)
http://mriquestions.com/magnetization‐transfer1.html
Water if more free to move in diseased tissue!
Diffusion Tensor Imaging (DTI)
From Oh J et al. Neurology 2013
DTI in Radiologically Isolated Syndrome
From Oh J et al. Neurology 2013
DTI in ALS
From Valsasina J et al. JNNP 2007
DTI in ALS
From Valsasina J et al. JNNP 2007
DTI in Experimental Trauma
From Wang‐Leandro J Trans Med 2018
SUMMARY#1: Both focal as well as diffuse and hidden spinal corddisease may affect patients with both traumatic andneurodegenerative conditions.
Objective #2: Spinal cord MRI is feasible, advancing butchallenging due to distinct anatomical features of thespinal cord.
Objective #3: Advanced quantitative MRI techniques canuncover otherwise hidden spinal cord pathology and candeliver biomarkers of neurodegeneration to be used asproof of concept clinical trials on neuroprotection andrepair.
Thank You for your kind attention
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