Intrinsic Cervical Spinal Cord Deformation on MRI

Ahmad, Iftikhar; Rosenbaum, Arthur E.; Yu, Frank Shiwei; Collins, George H.; Collins, Catherine S; Poe, L B

doi:10.1097/00002517-199612000-00006

Cited by 7 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Quantitative MRI studies of the SC (8)(9)(10)(11)(12) have been challenging, partly due to the technical challenges related to the small size of SC, and the presence of cerebral spinal fluid (CSF) pulsation associated with cardiac and respiratory cycles. To date, a variety of quantitative MRI methods (13,14) are available for the study of injured SC (12,(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26) and its recovery in behaving animals (27,28), which are also translatable to human SCI patients (28,29). The uniqueness and power of such an approach have been well demonstrated in our previous study in monkeys using multiparametric MRI (12).…”

Section: Introductionmentioning

confidence: 98%

Longitudinal assessment of spinal cord injuries in nonhuman primates with quantitative magnetization transfer

Wang

Mishra

et al. 2015

Magnetic Resonance in Med

View full text Add to dashboard Cite

Purpose This study aimed to evaluate the reproducibility and specificity of quantitative magnetization transfer (qMT) imaging for monitoring spinal cord injuries (SCIs). Methods MRI scans were performed in anesthetized monkeys at 9.4T, before and serially after a unilateral lesion of the cervical spinal cord. A two-pool fitting model was used to derive qMT parameters. Results qMT measures were reproducible across normal subjects, with an average pool size ratio (PSR) of 0.086 ± 0.003 (Mean ± SD) for gray matter, and 0.120 ± 0.005 for white matter, respectively. Compared to normal gray matter, the PSR of abnormal tissues rostral and caudal to the injury site decreased by 19.5% (p < 0.05), while the PSR of the cyst-like volume decreased drastically weeks after SCI. Strong correlations in cyst-like regions were observed between PSR and other MRI measures including longitudinal relaxation rate (R1), apparent diffusion coefficient (ADC) and fractional anisotropy (FA). Decreased PSR and FA values correlated well with demyelination in abnormal tissues. Conclusion The qMT parameters provide robust and specific information about the molecular and cellular changes produced by SCI. PSR detected demyelination and loss of macromolecules in abnormal tissue regions rostral and caudal to the cyst/lesion sites.

show abstract

Section: Introductionmentioning

confidence: 98%

Longitudinal assessment of spinal cord injuries in nonhuman primates with quantitative magnetization transfer

Wang

Mishra

et al. 2015

Magnetic Resonance in Med

View full text Add to dashboard Cite

show abstract

“…Conventional MRI methods, such as T 1 ‐weighted (T1W), T 2 ‐weighted (T2W), and diffusion‐weighted imaging (DWI), have previously been used to study spinal cord pathology and recovery after injury in animals and humans . In this study, we implemented diffusion tensor imaging (DTI), magnetization transfer (MT), and chemical exchange saturation transfer (CEST) imaging to characterize and quantify dynamic changes of injured spinal tissue.…”

Section: Introductionmentioning

confidence: 99%

Multiparametric MRI reveals dynamic changes in molecular signatures of injured spinal cord in monkeys

Wang

et al. 2014

Magnetic Resonance in Med

View full text Add to dashboard Cite

Purpose To monitor the spontaneous recovery of cervical spinal cord injury (SCI) using longitudinal multi-parametric MRI methods. Methods Quantitative MRI imaging including diffusion tensor imaging (DTI), magnetization transfer (MT), and chemical exchange saturation transfer (CEST) was conducted in anesthetized monkeys at 9.4 T. The structural, cellular and molecular features of the spinal cord were examined before and at different time-points after a dorsal column lesion in each monkey. Results Images with MT contrast enhanced visualization of the grey and white matter boundaries and the lesion, and permitted differentiation of core and rim compartments within an abnormal volume (AV). At early weeks after SCI, both core and rim exhibited low cellular density and low protein content, with high levels of exchanging hydroxyl, amine, and amide protons, as evidenced by increased apparent diffusion coefficient (ADC) value, decreased fractional anisotropy (FA), decreased magnetization transfer ratio (MTR), decreased nuclear Overhauser effect (NOE), and large CEST effects. Over time, while cellular density and fiber density increased, amide, amine, and hydroxyl levels dropped significantly, but at differing rates. Histology confirmed the nature of the AV to be a cyst. Conclusion Multi-parametric MRI offers a novel method to quantify the spontaneous changes in structure and cellular and molecular compositions of SC during spontaneous recovery from injury.

show abstract

“…However, in many in vivo human imaging studies of the spinal cord, the focus has primarily been on maximizing CSF-cord contrast rather than on delineating the internal gray-white structure. For example, in humans in vivo, Ahmad et al (15) have shown that when the cervical spinal cord is deformed through injury or disease, the distortions in the gray-white anatomy can be used as a reference to help determine the extent of damage. Similarly, in vivo longitudinal MRI studies in rats have shown a consistent loss in contrast between gray and white matter two days after traumatic injury, the loss of contrast mainly due to edema accumulated in the white matter (16).…”

mentioning

confidence: 99%

In vivo magnetic resonance imaging of the human cervical spinal cord at 3 Tesla

Korzan

Gorassini

Emery

et al. 2002

Magnetic Resonance Imaging

View full text Add to dashboard Cite

Purpose:To demonstrate the feasibility of obtaining highquality magnetic resonance (MR) images of the human cervical spinal cord in vivo at a magnetic field strength of 3 T and to optimize the signal contrast between gray matter, white matter, and cerebrospinal fluid (CSF) on 2D gradient recalled echo (GRE) images of the cervical spinal cord. Materials and Methods:Using a custom-built, anatomically molded radio frequency (RF) surface coil, the repetition time and flip angle of a 2D GRE sequence were systematically varied in five volunteers to assess tissue contrast in the cervical spinal cord.Results: The 2D GRE parameters for an optimal balance between gray-white matter and CSF-white matter contrast at 3 T were determined to be a time-to-repetition (TR) of 2000 msec and a flip angle of 45°, with the constant short time-to-echo (TE) of 12 msec used in this study. Excellent tissue contrast and visualization of the internal anatomy of the spinal cord was demonstrated reproducibly in eight subjects using these optimal parameters. Conclusion:This study demonstrates that imaging the cervical spinal cord and delineating internal spinal cord structures such as gray and white matter is feasible at 3 T.

show abstract

Intrinsic Cervical Spinal Cord Deformation on MRI

Cited by 7 publications

References 0 publications

Longitudinal assessment of spinal cord injuries in nonhuman primates with quantitative magnetization transfer

Longitudinal assessment of spinal cord injuries in nonhuman primates with quantitative magnetization transfer

Multiparametric MRI reveals dynamic changes in molecular signatures of injured spinal cord in monkeys

In vivo magnetic resonance imaging of the human cervical spinal cord at 3 Tesla

Contact Info

Product

Resources

About