MULTIPARAMETRIC MRI OF THE PEDIATRIC SPINAL CORD
MULTIPARAMETRIC MRI OF THE PEDIATRIC SPINAL CORD

Author: Shiva Shahrampour

Publisher:

Published: 2023

Total Pages: 0

ISBN-13:

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Quantitative magnetic resonance imaging (MRI) measurements of the pediatric spinal cord is important for both diagnostic and treatment planning. In recent years several quantitative MRI (qMRI) techniques that have been developed and tested to measure functional and structural information of the spinal cord tissue and microstructure. Several of the existing structural and functional imaging biomarkers (i.e., diffusion tensor imaging (DTI)) have demonstrated potential for providing microstructural information about the spinal cord. However, due to the lack of a standard anatomical template of the pediatric spinal cord, quantification of the spinal cord tissue has been challenging. Therefore, one of the goals of this work is to develop and test tools for quantification as well as the creation of a standard structural template of the typically developing (TD) pediatric spinal cord. This will allow automated measurement of normative values of the spinal cord cross-sectional area (SCCSA) at various levels of the spinal cord. Furthermore, to examine the white matter (WM) microstructure of the pediatric cord we developed a processing pipeline for the atlas-based generation of TD pediatric spinal cord WM tracts. This will facilitate the measurements of normative diffusion values for various WM tracts.A group of 30 TD subjects (age range of 6-17 years old (12.38 ±2.81)), who had no evidence of spinal cord injury or pathology were recruited. We utilized a multiparametric MRI protocol, including high-resolution T2-w structural and diffusion-weighted MRI images to scan the subjects on a 3T MRI scanner. The diffusion data were acquired using a novel iFOV DTI sequence. For quantification, a post-processing pipeline was utilized to generate the structural pediatric template. Next, WM tracts were generated using an atlas-based approach, and diffusion metrics (FA, MD, RD and AD) were quantified in 34 tracts identified in the processing pipeline. Normative SCCSA and DTI diffusion indices were generated for the TD population. Lastly, we demonstrated that DTI indices (i.e. FA) can be a predictive measure of components of the clinical test for spinal cord injury, as well as an indicator of the white matter tracts integrity. Therefore, in the final step of this work, we expanded our quantitative analysis to look at the microstructural and macrostructural changes in 15 children with chronic spinal cord injury (SCI) (AIS A-D, mean age of 12.8 ± 3.1 years). This included measurements of SCCSA, diffusion metrics and T2* WM/GM ratio of various white matter tracts in the patient population. We also examined the relationships between all the metrics and the ISNCSCI clinical scores in SCI subjects. We then compared these measurements between the TD and SCI patients to evaluate the diagnostic utility of these techniques and biomarkers. Statistically significant difference was observed between the two populations in the studied metrics. The results show that the proposed techniques may have the potential to be used as surrogate biomarkers for the quantification of the injured spinal cord. Keywords: diffusion tensor imaging, typically developing, spinal cord injury, spinal cord cross-sectional area, fractional anisotropy, mean diffusivity, axial diffusivity, radial diffusivity.

Pediatric Brain and Spine
Pediatric Brain and Spine

Author: L.M. Ketonen

Publisher: Springer Science & Business Media

Published: 2005-10-28

Total Pages: 505

ISBN-13: 3540264361

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MR Imaging and Spectroscopy of the Developing Brain.- Congenital Malformation of the Brain.- Inherited Neurological Diseases and Disorders of Myelin.- Acquired Toxic and Metabolic Brain Disorders.- Tumors: Paratentorial Neoplasms.- Tumors: Supratentorial Neoplasms.- Brain Damage.- Miscellaneous.- Vascular Abnormalities.- Temporal Bone.- Spine.- Fetal Imaging.

ACQUISITION, PROCESSING, AND ANALYSIS OF DIFFUSION TENSOR IMAGING AND ATROPHY MRI IN THE INJURED PEDIATRIC SPINAL CORD
ACQUISITION, PROCESSING, AND ANALYSIS OF DIFFUSION TENSOR IMAGING AND ATROPHY MRI IN THE INJURED PEDIATRIC SPINAL CORD

Author: Devon Middleton

Publisher:

Published: 2017

Total Pages: 110

ISBN-13:

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Spinal cord injury has the potential to be debilitating, particularly in the pediatric population. Identification of the exact injury level can be difficult from conventional structural Magnetic Resonance Imaging (MRI) scans, and younger children often have difficulty in participating in the clinical examinations that define neurologic damage. Because of limitations of existing clinical examinations and conventional imaging, more advanced quantitative imaging techniques are important for improvement in diagnostic and prognostic evaluation of spinal cord injury. A quantitative characterization of the full spinal cord injury from both a functional and structural perspective has not been performed in pediatric subjects and has potential to provide important diagnostic and prognostic information. Diffusion tensor imaging (DTI) gives a non-invasive quantification of water diffusion in the spinal cord and can provide insight into white matter integrity, while high resolution volumetric imaging can determine cord cross sectional area reflecting atrophy occurring post injury. Multiple challenges exist in analysis of pediatric spinal cord data, including physiological motion, low signal-to-noise, thermal noise and image artifact, and cumbersome measurements of cord morphology. In this work, a complete pipeline for the acquisition and analysis of both functional DTI data and high resolution structural data is designed, tested, and implemented including MR image acquisition, motion correction, diffusion tensor estimation, region of interest analysis, and semi-automated cord cross sectional area measurement. Data for both healthy subjects and subjects with spinal cord injury is collected and significant correlations are shown between DTI and cord morphology metrics. This characterization of the injured spinal cord using both structural and functional data has the potential to offer important new information for examination of spinal cord injury.

Multi Spectral Data Analysis for Diagnostic Enhancement of Pediatric Spinal Cord Injury
Multi Spectral Data Analysis for Diagnostic Enhancement of Pediatric Spinal Cord Injury

Author: Mahdi Alizadeh

Publisher:

Published: 2017

Total Pages: 85

ISBN-13:

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A key challenge in the imaging of spinal cord injury (SCI) patients is the ability to accurately determine structural or functional abnormality as well as level and severity of injury. Over the years a substantial number of studies have addressed this issue, however most of them utilized qualitative analysis of the acquired imaging data. Quantitative analysis of patients with SCI is an important issue in both diagnostic and treatment planning. Hence in this work new multispectral magnetic resonance (MR) image based approaches were developed for high-throughput extraction of quantitative features from pediatric spinal cord MR images and subsequent analysis using decision support algorithms. This may potentially improve diagnostic, prognostic, and predictive accuracy between typically developing (TD) pediatric spinal cord subjects and patients with SCI. The technique extracts information from both axial structural MRI images (such as T2-weighted gradient echo images) and functional MRI images (such as diffusion tensor images). The extracted data contains first order statistics (diffusion tensor tractography and histogram based texture descriptors), second order (co-occurrence indices) and high order (wavelet primitives) statistics. MRI data from total of 43 subjects that includes 23 healthy TD subjects with the age range of 6-16 (11.94±3.26 (mean ±standard deviation)) who had no evidence of SCI or pathology and 20 SCI subjects with the age range of 7-16 (11.28±3.00 (mean ±standard deviation)) were recruited and scanned using 3.0T Siemens Verio MR scanner. Standard 4-channel neck matrix and 8-channel spine array RF coils were used for data collection. After data collection various post processing methods were used to improve the data quality. A novel ghost artifact suppression technique was implemented and tested. Initially, 168 quantitative measures of multi-spectral images (functional and structural) were calculated by using regions of interest (ROIs) manually drawn on the whole cord along the entire spinal cord being anatomically localized by an independent board certified neuroradiologist. These measures were then statistically compared between TD and SCI groups using standard least squared linear regression model based on restricted maximum likelihood (REML) method. Statistically, significant changes have been shown in 44 features: 30 features obtained from functional images and 14 features selected from structural images. Also, it has been shown that the quantitative measures of the spinal cord in DTI and T2W-GRE images above and below injury level were altered significantly. Finally, tractography measures were also obtained on a subset of the patients to demonstrate quantitative analysis of the extracted white matter structures. Overall the results show that the proposed techniques may have potential to be used as surrogate biomarkers for detection of the injured spinal cord. These measures enable us to quantify the functional and structural plasticity in chronic SCI and consequently has the potential to improve our understanding of damage and recovery in diseased states of the spinal cord.

Diffusion Tensor Imaging (DTI) of the Pediatric Spinal Cord
Diffusion Tensor Imaging (DTI) of the Pediatric Spinal Cord

Author: Nadia Barakat

Publisher:

Published: 2012

Total Pages: 134

ISBN-13:

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Diffusion Tensor Imaging (DTI) is a technique for noninvasively examining diffusion of water molecules in each voxel of an image in directions parallel and transverse to the plane of neuronal axons. The quantitative characteristic of DTI allows for the characterization of physical properties of tissues. The unique characteristic architecture of the spinal cord allows DTI to characterize cord white matter, separate white from gray matter and assess structural damage of the cord. While studies on diffusion imaging of the spinal cord in adults, as well as in animal models have been reported, a comprehensive study of the pediatric spinal cord examining the accuracy and reproducibility of DTI measures has not yet been reported. The purpose of this study is to (a) evaluate the accuracy of cervical spinal cord DTI in children using a newly developed inner-Field-of-View (iFoV) sequence with spatially selective 2D RF excitations, (b) investigate reproducibility of the DTI measures and (c) examine correlation of DTI with standardized clinical exams. Twenty-five pediatric control subjects and ten pediatric patients with Spinal Cord Injuries (SCI) were recruited. The iFoV DTI pulse sequence was implemented on a 3 Tesla MRI scanner. The protocol was optimized for imaging the pediatric spinal cord and tested on phantom models, human cadaveric spine and adult subjects. All thirty-five pediatric subjects underwent two DTI scans of the spinal cord. Imaging results were compared between controls and patients with SCI. Statistical analysis was performed to examine reproducibility of DTI parameters and their correlation with standard clinical examinations. Results showed reduced FA and increased diffusivity values (AD, RD and MD) in patients compared to controls. Reproducibility of the different DTI parameters showed moderate to strong agreement between the repeated-measurements scans. Correlations between clinical examinations (ISNCSCI and MRI scores) and DTI values showed that DTI predicts sacral sparing outcomes, motor and MRI levels in the injured spinal cord with good to strong accuracy. Results also revealed that DTI values differ between children with and without cervical SCI and between children with SCI who have incomplete injuries and complete injuries. Finally, the study showed DTI to have relatively low specificity values for AC and DAP, compared with specificity for S4-5 sensation, and that the combination of the three DTI parameters FA, AD and RD was the strongest predictor of both motor level and MRI level of injury. This study was the first to demonstrate the feasibility of pediatric spinal cord DTI and produced accurate and reliable DTI measures.

The Central Nervous System of Vertebrates
The Central Nervous System of Vertebrates

Author: Rudolf Nieuwenhuys

Publisher: Springer Science & Business Media

Published: 1998

Total Pages: 2270

ISBN-13: 9783540560135

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This comprehensive reference is clearly destined to become the definitive anatomical basis for all molecular neuroscience research. The three volumes provide a complete overview and comparison of the structural organisation of all vertebrate groups, ranging from amphioxus and lamprey through fishes, amphibians and birds to mammals. This thus allows a systematic treatment of the concepts and methodology found in modern comparative neuroscience. Neuroscientists, comparative morphologists and anatomists will all benefit from: * 1,200 detailed and standardised neuroanatomical drawings * the illustrations were painstakingly hand-drawn by a team of graphic designers, specially commissioned by the authors, over a period of 25 years * functional correlations of vertebrate brains * concepts and methodology of modern comparative neuroscience * five full-colour posters giving an overview of the central nervous system of the vertebrates, ideal for mounting and display This monumental work is, and will remain, unique; the only source of such brilliant illustrations at both the macroscopic and microscopic levels.

Vertebral Lesions
Vertebral Lesions

Author: Luigi Manfrè

Publisher: Springer

Published: 2017-09-06

Total Pages: 169

ISBN-13: 3319526340

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This easy-to-consult guide describes new minimally invasive procedures for the treatment of vertebral lesions that are accompanied by fewer complications and side-effects, reduce the risks of anesthesia, and lower costs. Clear accounts are provided of CT and X-ray guided techniques for vertebral augmentation in different regions of the spine and for the treatment of vertebral tumors by means of cryoablation, radiofrequency ablation, and embolization. Helpful information is also provided on imaging, biomechanics, biopsy, and biomaterials. Like other books in the Springer series New Procedures in Spinal Interventional Neuroradiology, this practice-oriented volume will fill a significant gap in the literature and meet the need expressed by a large number of specialists (interventional neuroradiologists and radiologists, neurosurgeons, and orthopedists) for a topical and handy guide that specifically illustrates the presently available materials and methods.

Handbook of Neuro-Oncology Neuroimaging
Handbook of Neuro-Oncology Neuroimaging

Author: Herbert B. Newton

Publisher: Academic Press

Published: 2022-08-21

Total Pages: 1022

ISBN-13: 0128229950

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With treatment approaches and the field of neuro-oncology neuroimaging changing rapidly, this third edition of the Handbook of Neuro-Oncology Neuroimaging is very relevant to those in the field, providing a single-source, comprehensive, reference handbook of the most up-to-date clinical and technical information regarding the application of neuroimaging techniques to brain tumor and neuro-oncology patients. This new volume will have updates on all of the material from the second edition, and in addition features several new important chapters covering diverse topics such as imaging for the use of Laser Interstitial Thermal Therapy, advanced imaging techniques in radiation therapy, therapeutic treatment fields, response assessment in clinical trials, surgical planning of neoplastic disease of the spine, and more. Sections first overview neuro-oncological disorders before delving into the physics and basic science of neuroimaging and great focus on CT and MRI. The book then focuses on advances in the neuroimaging of brain tumors and neuroimaging of specific tumor types. There is also discussion of neuroimaging of other neuro-oncological syndromes. This book will serve as a resource of background information to neuroimaging researchers and basic scientists with an interest in brain tumors and neuro-oncology. Summarizes translational research on brain imaging for brain tumors Discusses limitations of neuroimaging for diagnosis and treatment Presents advanced imaging technologies, including CT, MRI, and PET Contains new coverage on Laser Interstitial Thermal Therapy, radiation therapy, clinical trials, and more