scholarly journals Normalization of Spinal Cord Total Cross-Sectional and Gray Matter Areas as Quantified With Radially Sampled Averaged Magnetization Inversion Recovery Acquisitions

2021 ◽  
Vol 12 ◽  
Author(s):  
Eva M. Kesenheimer ◽  
Maria Janina Wendebourg ◽  
Matthias Weigel ◽  
Claudia Weidensteiner ◽  
Tanja Haas ◽  
...  

Background: MR imaging of the spinal cord (SC) gray matter (GM) at the cervical and lumbar enlargements' level may be particularly informative in lower motor neuron disorders, e. g., spinal muscular atrophy, but also in other neurodegenerative or autoimmune diseases affecting the SC. Radially sampled averaged magnetization inversion recovery acquisition (rAMIRA) is a novel approach to perform SC imaging in clinical settings with favorable contrast and is well-suited for SC GM quantitation. However, before applying rAMIRA in clinical studies, it is important to understand (i) the sources of inter-subject variability of total SC cross-sectional areas (TCA) and GM area (GMA) measurements in healthy subjects and (ii) their relation to age and sex to facilitate the detection of pathology-associated changes. In this study, we aimed to develop normalization strategies for rAMIRA-derived SC metrics using skull and spine-based metrics to reduce anatomical variability.Methods: Sixty-one healthy subjects (age range 11–93 years, 37.7% women) were investigated with axial two-dimensional rAMIRA imaging at 3T MRI. Cervical and thoracic levels including the level of the cervical (C4/C5) and lumbar enlargements (Tmax) were examined. SC T2-weighted sagittal images and high-resolution 3D whole-brain T1-weighted images were acquired. TCA and GMAs were quantified. Anatomical variables with associations of |r| > 0.30 in univariate association with SC areas, and age and sex were used to construct normalization models using backward selection with TCAC4/C5 as outcome. The effect of the normalization was assessed by % relative standard deviation (RSD) reductions.Results: Mean inter-individual variability and the SD of the SC area metrics were considerable: TCAC4/5: 8.1%/9.0; TCATmax: 8.9%/6.5; GMAC4/C5: 8.6%/2.2; GMATmax: 12.2%/3.8. Normalization based on sex, brain WM volume, and spinal canal area resulted in RSD reductions of 23.7% for TCAs and 12.0% for GM areas at C4/C5. Normalizations based on the area of spinal canal alone resulted in RSD reductions of 10.2% for TCAs and 9.6% for GM areas at C4/C5, respectively.Discussion: Anatomic inter-individual variability of SC areas is substantial. This study identified effective normalization models for inter-subject variability reduction in TCA and SC GMA in healthy subjects based on rAMIRA imaging.

2020 ◽  
Vol 14 ◽  
Author(s):  
Laura Sander ◽  
Antal Horvath ◽  
Simon Pezold ◽  
Simon Andermatt ◽  
Michael Amann ◽  
...  

Background: Brainstem-mediated functions are impaired in neurodegenerative diseases and aging. Atrophy can be visualized by MRI. This study investigates extrinsic sources of brainstem volume variability, intrinsic sources of anatomical variability, and the influence of age and sex on the brainstem volumes in healthy subjects. We aimed to develop efficient normalization strategies to reduce the effects of intrinsic anatomic variability on brainstem volumetry.Methods: Brainstem segmentation was performed from MPRAGE data using our deep-learning-based brainstem segmentation algorithm MD-GRU. The extrinsic variability of brainstem volume assessments across scanners and protocols was investigated in two groups comprising 11 (median age 33.3 years, 7 women) and 22 healthy subjects (median age 27.6 years, 50% women) scanned twice and compared using Dice scores. Intrinsic anatomical inter-individual variability and age and sex effects on brainstem volumes were assessed in segmentations of 110 healthy subjects (median age 30.9 years, range 18–72 years, 53.6% women) acquired on 1.5T (45%) and 3T (55%) scanners. The association between brainstem volumes and predefined anatomical covariates was studied using Pearson correlations. Anatomical variables with associations of |r| > 0.30 as well as the variables age and sex were used to construct normalization models using backward selection. The effect of the resulting normalization models was assessed by % relative standard deviation reduction and by comparing the inter-individual variability of the normalized brainstem volumes to the non-normalized values using paired t- tests with Bonferroni correction.Results: The extrinsic variability of brainstem volumetry across different field strengths and imaging protocols was low (Dice scores > 0.94). Mean inter-individual variability/SD of total brainstem volumes was 9.8%/7.36. A normalization based on either total intracranial volume (TICV), TICV and age, or v-scale significantly reduced the inter-individual variability of total brainstem volumes compared to non-normalized volumes and similarly reduced the relative standard deviation by about 35%.Conclusion: The extrinsic variability of the novel brainstem segmentation method MD-GRU across different scanners and imaging protocols is very low. Anatomic inter-individual variability of brainstem volumes is substantial. This study presents efficient normalization models for variability reduction in brainstem volumetry in healthy subjects.


2001 ◽  
Vol 1230 ◽  
pp. 1154-1155
Author(s):  
Nobuhiro Tsukamoto ◽  
Hideo Kumagai ◽  
Kiichiro Saitoh ◽  
Masahiko Monma ◽  
Yutaka Ando ◽  
...  

2000 ◽  
Vol 123 (1) ◽  
pp. 71-79 ◽  
Author(s):  
Francis Loth ◽  
M. Atif Yardimci ◽  
Noam Alperin

The fluid that resides within cranial and spinal cavities, cerebrospinal fluid (CSF), moves in a pulsatile fashion to and from the cranial cavity. This motion can be measured by magnetic resonance imaging (MRI) and may be of clinical importance in the diagnosis of several brain and spinal cord disorders such as hydrocephalus, Chiari malformation, and syringomyelia. In the present work, a geometric and hydrodynamic characterization of an anatomically relevant spinal canal model is presented. We found that inertial effects dominate the flow field under normal physiological flow rates. Along the length of the spinal canal, hydraulic diameter was found to vary significantly from 5 to 15 mm. The instantaneous Reynolds number at peak flow rate ranged from 150 to 450, and the Womersley number ranged from 5 to 17. Pulsatile flow calculations are presented for an idealized geometric representation of the spinal cavity. A linearized Navier–Stokes model of the pulsatile CSF flow was constructed based on MRI flow rate measurements taken on a healthy volunteer. The numerical model was employed to investigate effects of cross-sectional geometry and spinal cord motion on unsteady velocity, shear stress, and pressure gradient fields. The velocity field was shown to be blunt, due to the inertial character of the flow, with velocity peaks located near the boundaries of the spinal canal rather than at the midpoint between boundaries. The pressure gradient waveform was found to be almost exclusively dependent on the flow waveform and cross-sectional area. Characterization of the CSF dynamics in normal and diseased states may be important in understanding the pathophysiology of CSF related disorders. Flow models coupled with MRI flow measurements may become a noninvasive tool to explain the abnormal dynamics of CSF in related brain disorders as well as to determine concentration and local distribution of drugs delivered into the CSF space.


Spinal Cord ◽  
2014 ◽  
Vol 52 (8) ◽  
pp. 616-620 ◽  
Author(s):  
C Wang ◽  
R C Tam ◽  
E Mackie ◽  
D K B Li ◽  
A L Traboulsee

2018 ◽  
Vol 60 (5) ◽  
pp. 623-627
Author(s):  
Mingming Miao ◽  
Xiangtao Lin ◽  
Zhonghe Zhang ◽  
Hui Zhao

Background The studies that described the dimensions of the normal fetal thoracic spinal canal and spinal cord on magnetic resonance imaging (MRI) are scarce. Purpose To determine the normal appearance of the fetal spinal canal and spinal cord at T12 across different gestational ages using 3.0-T MRI. Material and Methods The spines of 43 normal human fetuses, aged 15–40 weeks, were scanned by 3.0-T MRI. All specimens were scanned using a GE 3.0-T MRI scanner. Imaging of the T12 vertebrae was performed in the coronal, sagittal, and axial planes. The anterior-posterior (AP) diameter, width, and cross-sectional area of the spinal canal and spinal cord at T12 were measured. The influence of gestational age on these parameters was investigated with a scatter plot and linear regression analysis using Pearson correlation coefficient. Results The normal morphology of the fetal vertebra at T12 can be clearly showed by MRI; the spinal canal appeared circular, while the spinal cord was ellipsoid. Linear regression analysis showed a significant positive correlation between the AP diameter, width, and cross-sectional area of the spinal canal at T12 and gestational age. Conclusion Postmortem MRI is a reliable method for understanding the growth dynamics of the spinal canal and spinal cord at T12. Findings from this study would benefit the prenatal diagnosis of congenital malformations by MRI.


2020 ◽  
Author(s):  
Zhou Run-tian ◽  
Zhao Yi-bo ◽  
Lu Xiang-dong ◽  
Zhao Xiao-feng ◽  
Wang Xiao-nan ◽  
...  

Abstract Backgrounds: Cervical vertebral dome expansion laminoplasty is a new surgical method for the treatment of cervical spondylosis. We analyzed correlations between the selection of microtitanium plates with different specifications for use in a cervical vertebral dome expansion laminoplasty to establish guidance for the selection of suitable microtitanium plates.Methods: Sixteen patients that underwent the new, full lamina posterior spinal canal enlargement with a cervical spinal stenosis angioplasty procedure for treatment of their cervical spinal cords were recruited at our hospital. From February 2017-September 2018, medical records confirmed that all patients underwent cervical CT and MRI tests pre- and postsurgery. The anteroposterior diameter of the spinal canal, changes in the cross-sectional area of the spinal canal, and the pre- and postsurgery distance of the cervical spinal cord after applying microtitanium plates with different lengths were measured by Mimics version 17.0 software. A statistical regression and correlation analysis of relevant specification parameters of the microtitanium plate was then studied.Results: As the size of the microtitanium plate increased, we found that the cross-sectional area of cervical spinal canal and distance between the descendants of the lamina and the distance of cervical spinal cord concordantly increased. The regression equation associated with sagittal diameter, cross-sectional area, and posterior movement distance of the cervical spinal cord was obtained.Conclusions: The use of the corresponding regression equations enabled the prediction of the cervical spinal canal parameters and posterior movement distance of the cervical spinal cord when adopting different specifications of the microtitanium plate for different segments of the cervical vertebrae. This analysis guided the selection of microtitanium plates with appropriate specifications for different cervical vertebrae in a cervical vertebral dome expansion laminoplasty.


PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0247813
Author(s):  
Adrien Goujon ◽  
Sonia Mirafzal ◽  
Kevin Zuber ◽  
Romain Deschamps ◽  
Jean-Claude Sadik ◽  
...  

Background and purpose To compare 3D-Fast Gray Matter Acquisition with Phase Sensitive Inversion Recovery (3D-FGAPSIR) with conventional 3D-Short-Tau Inversion Recovery (3D-STIR) and sagittal T1-and T2-weighted MRI dataset at 3 Tesla when detecting MS spinal cord lesions. Material and methods This prospective single-center study was approved by an institutional review board and enrolled participants from December 2016 to August 2018. Two neuroradiologists blinded to all data, individually analyzed the 3D-FGAPSIR and the conventional datasets separately and in random order. Discrepancies were resolved by consensus by a third neuroradiologist. The primary judgment criterion was the number of MS spinal cord lesions. Secondary judgment criteria included lesion enhancement, lesion delineation, reader-reported confidence and lesion-to-cord-contrast-ratio. A Wilcoxon’s test was used to compare the two datasets. Results 51 participants were included. 3D-FGAPSIR detected significantly more lesions than the conventional dataset (344 versus 171 respectively, p<0.001). Two participants had no detected lesion on the conventional dataset, whereas 3D-FGAPSIR detected at least one lesion. 3/51 participants had a single enhancing lesion detected by both datasets. Lesion delineation and reader-reported confidence were significantly higher with 3D-FGAPSIR: 4.5 (IQR 1) versus 2 (IQR 0.5), p<0.0001 and 4.5 (IQR 1) versus 2.5 (IQR 0.5), p<0.0001. Lesion-to-cord-contrast-ratio was significantly higher using 3D-FGAPSIR as opposed to 3D-STIR and T2: 1.4 (IQR 0,3) versus 0.4 (IQR 0,1) and 0.3 (IQR 0,1)(p = 0.04). Correlations with clinical data and inter- and intra-observer agreements were higher with 3D-FGAPSIR. Conclusion 3D-FGAPSIR improved overall MS spinal cord lesion detection as compared to conventional set and detected all enhancing lesions.


2020 ◽  
Author(s):  
Simon Henmar ◽  
Erik B. Simonsen ◽  
Rune W. Berg

The gray matter of the spinal cord is the seat of somata of various types of neurons devoted to the sensory and motor activities of the limbs and trunk as well as a part of the autonomic nervous system. The volume of the spinal gray matter is an indicator of the local neuronal processing and this can decrease due to atrophy associated with degenerative diseases and injury. Nevertheless, the absolute volume of the human spinal cord has rarely been reported, if ever. Here, we use high–resolution magnetic resonance imaging, with a cross–sectional resolution of 50 × 50μm2 and a voxel size of 0.0005mm3, to estimate the total gray and white matter volume of a post mortem human female spinal cord. Segregation of gray and white matter was accomplished using deep learning image segmentation. Further, we include data from a male spinal cord of a previously published study. The gray and white matter volumes were found to be 2.87 and 11.33 ml, respectively for the female and 3.55 and 19.33 ml, respectively for a male. The gray and white matter profiles along the vertebral axis were found to be strikingly similar and the volumes of the cervical, thoracic and lumbosacral sections were almost equal.NEW AND NOTEWORTHYHere, we combine high field MRI (9.4T) and deep learning for a post-mortem reconstruction of the gray and white matter in human spinal cords. We report a minuscule total gray matter volume of 2.87 ml for a female and 3.55 ml for a male. For comparison, these volumes correspond approximately to the distal digit of the little finger.


Sign in / Sign up

Export Citation Format

Share Document