BACKGROUND AND PURPOSE: DTI data of the normal healthy spinal cord in children are limited compared with adults and are typically focused on the cervical spinal cord. The purpose of this study was the following: to investigate the feasibility of obtaining repeatable DTI parameters along the entire cervical and thoracic spinal cord as a function of age in typically developing pediatric subjects; to analyze the DTI parameters among different transverse levels of the cervical and thoracic spinal cord; and to examine the sex differences in DTI parameters along the cervical and thoracic spinal cord. MATERIALS AND METHODS: Twenty-two subjects underwent 2 identical scans by using a 3T MR imaging scanner. Axial diffusion tensor images were acquired by using 2 overlapping slabs to cover the cervical and thoracic spinal cord. After postprocessing, DTI parameters were calculated by using ROIs drawn on the whole cord along the entire spinal cord for both scans. RESULTS: An increase in fractional anisotropy and a decrease in mean diffusivity, axial diffusivity, and radial diffusivity were observed with age along the entire spinal cord. Significantly lower fractional anisotropy and higher mean diffusivity values were observed in the lower cervical cord compared with the upper cervical cord. Axial diffusivity values in the cervical cord were higher compared with the thoracic cord. No statistically significant sex differences were observed for all DTI parameters. There was a moderate-to-strong repeatability for all DTI parameters. CONCLUSIONS: This study provides an initial understanding of DTI values of the spinal cord relevant to age and sex and shows that obtaining repeatable DTI values of the entire cord in children is feasible.
Magnetic resonance based diffusion imaging has been gaining more utility and clinical relevance over the past decade. Using conventional echo planar techniques, it is possible to acquire and characterize water diffusion within the central nervous system (CNS); namely in the form of Diffusion Weighted Imaging (DWI) and Diffusion Tensor Imaging (DTI). While each modality provides valuable clinical information in terms of the presence of diffusion and its directionality, both techniques are limited to assuming an ideal Gaussian distribution for water displacement with no intermolecular interactions. This assumption neglects pathological processes that are not Gaussian therefore reducing the amount of potentially clinically relevant information. Additions to the Gaussian distribution measured by the excess kurtosis, or peakedness, of the probabilistic model provide a better understanding of the underlying cellular structure. The objective of this work is to provide mathematical and experimental evidence that Diffusion Kurtosis Imaging (DKI) can offer additional information about the micromolecular environment of the pediatric spinal cord. This is accomplished by a more thorough characterization of the nature of random water displacement within the cord. A novel DKI imaging sequence based on a tilted 2D spatially selective radio frequency pulse providing reduced field of view (FOV) imaging was developed, implemented, and optimized on a 3 Tesla MRI scanner, and tested on pediatric subjects (healthy subjects: 15; patients with spinal cord injury (SCI):5). Software was developed and validated for post processing of the DKI images and estimation of the tensor parameters. The results show statistically significant differences in mean kurtosis (p < 0.01) and radial kurtosis (p < 0.01) between healthy subjects and subjects with SCI. DKI provides incremental and novel information over conventional diffusion acquisitions when coupled with higher order estimation algorithms.
29 July 2021 in American Journal of Neuroradiology
In the update of selegiline (27 November 1989, page 95) we concluded that the drug had not been proven to delay the progression of Parkinson’s disease. Interim results from the large DATATOP trial now provides strong evidence that selegiline 10mg/day delays the untreated disease (The Parkinson Study Group. N Engl J. Med 1989; 321: 1364–71). The report appeared after we had gone to press.
Traumatic Brain and Spinal Cord Injury comprehensively covers the medical and pathological issues related to neurotrauma and its often devastating consequences. Written by globally renowned experts in the field, both clinicians and researchers will find this book invaluable to update their knowledge. This volume is divided into two sections, one covering the brain, the other the spinal cord. Each section discusses the following topics: • The demographic in the developed and developing world where neurotrauma is witnessing a massive expansion • Major clinical issues including advanced semi-experimental monitoring techniques utilized by neurosurgeons and intensivists and the potential use of identifying markers of tissue injury • Overview of major pathophysiological changes • The development of animal models; successes and limitations • Past, current and future therapeutic strategies including rehabilitative opportunities. Presenting the most up-to-date clinical and experimental research in neurotrauma, this volume is essential reading for neurologists, neurosurgeons, intensive care physicians and rehabilitative physicians.
1 March 2016 in Topics in Spinal Cord Injury Rehabilitation
Background: The restoration of walking ability in the spinal cord injury (SCI) population is an increasingly important goal in physical therapy. Locomotor training (LT) is often implemented with the aim to restore ambulation. At this point, there are no guidelines for LT in the pediatric SCI population. Objectives: The aim of this review is to further narrow the effects of LT to the pediatric SCI population and develop recommendations for pediatric LT. Methods: A thorough search was performed using the following databases: Scopus, CINAHL, PubMed, and Ovid. Studies were selected based on the following inclusion criteria: pediatric SCI population, articles published within last 10 years, human subjects, and LT. Studies looking at other neurological disorders and subjects who were not previously ambulatory were excluded. Five students and one Faculty Research Advisor from the university's Doctor of Physical Therapy Program evaluated the inclusion criteria, conducted a risk of bias assessment using the Downs and Black checklist, and extracted the results. Results: Six studies were selected for this review. They showed gains in distance, gait speed, walking independence, and participation. There were variations in results when comparing gains in injury level based on the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI). Conclusions: Currently there is insufficient evidence to determine the best clinical practice guidelines for rehabilitation using LT within the pediatric SCI population.