Metabolic profile of complete spinal cord injury in pons and cerebellum: A 3T 1H MRS study.

The aim of this exploratory study was the assessment of the metabolic profiles of persons with complete spinal cord injury (SCI) in three region-of-interests (pons, cerebellar vermis, and cerebellar hemisphere), with magnetic resonance spectroscopy, and their correlations to clinical scores. Group differences and association between metabolic and clinical scores were examined. Fifteen people with chronic SCI (cSCI), five people with subacute SCI (sSCI) and fourteen healthy controls were included. Group comparison between cSCI and HC showed lower total N-acetyl-aspartate (tNAA) in the pons (p = 0.04) and higher glutathione (GSH) in the cerebellar vermis (p = 0.02). Choline levels in the cerebellar hemisphere were different between cSCI and HC (p = 0.02) and sSCI and HC (p = 0.02). A correlation was reported for choline containing compounds (tCho) to clinical scores in the pons (rho = - 0.55, p = 0.01). tNAA to total creatine (tNAA/tCr ratio) correlated to clinical scores in the cerebellar vermis (rho = 0.61, p = 0.004) and GSH correlated to the independence score in the cerebellar hemisphere (rho = 0.56, p = 0.01). The correlation of tNAA, tCr, tCho and GSH to clinical scores might be indicators on how well the CNS copes with the post-traumatic remodeling and might be further examined as outcome markers.

Functional connectivity and amplitude of low-frequency fluctuations changes in people with complete subacute and chronic spinal cord injury.

After spinal cord injury (SCI), reorganization processes and changes in brain connectivity occur. Besides the sensorimotor cortex, the subcortical areas are strongly involved in motion and executive control. This exploratory study focusses on the cerebellum and vermis. Resting-state functional magnetic resonance imaging (fMRI) was performed. Between-group differences were computed using analysis of covariance and post-hoc tests for the seed-based connectivity measure with vermis and cerebellum as regions of interest. Twenty participants with complete SCI (five subacute SCI, 15 with chronic SCI) and 14 healthy controls (HC) were included. Functional connectivity (FC) was lower in all subjects with SCI compared with HC in vermis IX, right superior frontal gyrus (pFDR = 0.008) and right lateral occipital cortex (pFDR = 0.036). In addition, functional connectivity was lower in participants with chronic SCI compared with subacute SCI in bilateral cerebellar crus I, left precentral- and middle frontal gyrus (pFDR = 0.001). Furthermore, higher amplitude of low-frequency fluctuations (ALFF) was found in the left thalamus in individuals with subacute SCI (pFDR = 0.002). Reduced FC in SCI indicates adaptation with associated deficit in sensory and motor function. The increased ALFF in subacute SCI might reflect reorganization processes in the subacute phase.

The Torg-Pavlov ratio for the prediction of acute spinal cord injury after a minor trauma to the cervical spine.

BACKGROUND CONTEXT: Acute cervical spinal cord injury (SCI) has been observed in some patients after a minor trauma to the cervical spine. The discrepancy between the severity of the trauma and the clinical symptoms has been attributed to spinal canal stenosis. However, to date, there is no universally established radiological parameter for identifying critical spinal stenosis in these patients. The spinal canal-to-vertebral body ratio (Torg-Pavlov ratio) has been proposed for assessing developmental spinal canal stenosis. The relevance of the Torg-Pavlov ratio for predicting the occurrence and severity of acute cervical SCI after a minor trauma to the cervical spine has not yet been established. PURPOSE: To investigate the Torg-Pavlov ratio values of the cervical spine in patients suffering from acute cervical SCI after a minor trauma to the cervical spine and the use of the Torg-Pavlov ratio for identifying patients at risk of cervical SCI and predicting the severity and course of symptoms. STUDY DESIGN/SETTING: Retrospective radiological study of consecutive patients. PATIENT SAMPLE: Forty-five patients suffering from acute cervical SCI and 68 patients showing no neurologic symptoms after a minor trauma to the cervical spine. OUTCOME MEASURES: Midvertebral sagittal cervical spinal canal diameter and the sagittal vertebral body diameter. Calculation of the Torg-Pavlov ratio values. METHODS: Conventional lateral radiographs of the cervical spine (C3-C7) were analyzed to determine the Torg-Pavlov ratio values. Receiver operating characteristic curves were calculated for evaluating the classification accuracy of the Torg-Pavlov ratio for predicting SCI. RESULTS: The Torg-Pavlov ratio values in the SCI group were significantly (p<.04) smaller compared with that in the control group. A Torg-Pavlov ratio cutoff value of 0.7 yielded the greatest positive likelihood ratio for predicting the occurrence of SCI. However, there were no significant differences in the Torg-Pavlov ratio values between the different American Spinal Injury Association Impairment Score groups and between patients with complete, partial, and no recovery of symptoms. CONCLUSIONS: Developmental cervical spinal canal stenosis assessed by the Torg-Pavlov ratio was characteristic for patients suffering from acute cervical SCI after a minor trauma to the cervical spine. Patients at risk of SCI after a minor trauma to the cervical spine can be identified by applying a Torg-Pavlov ratio cutoff value of 0.7. Other factors in addition to the spinal canal-to-vertebral body ratio affect the severity and course of symptoms as a result of cervical SCI.