MR Imaging for Assessing Injury Severity and Prognosis in Acute Traumatic Spinal Cord Injury

Ferroptosis inhibitor improves outcome after early and delayed treatment in mild spinal cord injury

We show that redox active iron can induce a regulated form of non-apoptotic cell death and tissue damage called ferroptosis that can contribute to secondary damage and functional loss in the acute and chronic periods after spinal cord injury (SCI) in young, adult, female mice. Phagocytosis of red blood cells at sites of hemorrhage is the main source of iron derived from hemoglobin after SCI. Expression of hemeoxygenase-1 that induces release of iron from heme, is increased in spinal cord macrophages 7 days after injury. While iron is stored safely in ferritin in the injured spinal cord, it can, however, be released by NCOA4-mediated shuttling of ferritin to autophagosomes for degradation (ferritinophagy). This leads to the release of redox active iron that can cause free radical damage. Expression of NCOA4 is increased after SCI, mainly in macrophages. Increase in the ratio of redox active ferrous (Fe2+) to ferric iron (Fe3+) is also detected after SCI by capillary electrophoresis inductively coupled mass spectrometry. These changes are accompanied by other hallmarks of ferroptosis, i.e., deficiency in various elements of the antioxidant glutathione (GSH) pathway. We also detect increases in enzymes that repair membrane lipids (ACSL4 and LPCAT3) and thus promote on-going ferroptosis. These changes are associated with increased levels of 4-hydroxynonenal (4-HNE), a toxic lipid peroxidation product. Mice with mild SCI (30 kdyne force) treated with the ferroptosis inhibitor (UAMC-3203-HCL) either early or delayed times after injury showed improvement in locomotor recovery and secondary damage. Cerebrospinal fluid and serum samples from human SCI cases show evidence of increased iron storage (ferritin), and other iron related molecules, and reduction in GSH. Collectively, these data suggest that ferroptosis contributes to secondary damage after SCI and highlights the possible use of ferroptosis inhibitors to treat SCI.

Clinical characteristics analysis of pediatric spinal cord injury without radiological abnormality in China: a retrospective study

PURPOSE

This study aims to analyze the clinical characteristics of Chinese children with spinal cord injury (SCI) without radiographic abnormality (SCIWORA) and explore their contributing factors and mechanisms of occurrence.

METHODS

A retrospective analysis was conducted on the clinical data of pediatric patients diagnosed with SCIWORA from January 2005 to May 2020. Epidemiological, etiological, mechanistic, therapeutic, and outcome aspects were analyzed.

RESULTS

A total of 47 patients with SCIWORA were included in this study, comprising 16 males and 31 females. The age range was 4 to 12 years, with an average age of 7.49 ± 2.04 years, and 70% of the patients were below eight. Sports-related injuries constituted 66%, with 70% attributed to dance backbend practice. Thoracic segment injuries accounted for 77%. In the American Spinal Injury Association (ASIA) classification, the combined proportion of A and B grades accounted for 88%. Conservative treatment was chosen by 98% of the patients, with muscle atrophy, spinal scoliosis, hip joint abnormalities, and urinary system infections being the most common complications.

CONCLUSION

SCIWORA in Chinese children is more prevalent in those under eight years old, with a higher incidence in females than males. Thoracic spinal cord injuries are predominant, dance backbend as a primary contributing factor, and the social environment of "neijuan" is a critical potential inducing factor. Furthermore, the initial severity of the injury plays a decisive role in determining the prognosis of SCIWORA.

Does Magnetic Resonance Imaging Predict Neurological Deficit in Patients with Traumatic Lower Lumbar Fractures?

STUDY DESIGN

A retrospective cohort study.

PURPOSE

This study aimed to understand the role of magnetic resonance imaging (MRI) in predicting neurological deficits in traumatic lower lumbar fractures (LLFs; L3-L5).

OVERVIEW OF LITERATURE

Despite studies on the radiological risk factors for neurological deficits in thoracolumbar fractures, very few have focused on LLFs. Moreover, the potential utility of MRI in LLFs has not been evaluated.

METHODS

In total, 108 patients who underwent surgery for traumatic LLFs between January 2010 and January 2020 were reviewed to obtain their demographic details, injury level, and neurology status at the time of presentation (American Spinal Injury Association [ASIA] grade). Preoperative computed tomography scans were used to measure parameters such as anterior vertebral body height, posterior vertebral body height, loss of vertebral body height, local kyphosis, retropulsion of fracture fragment, interpedicular distance, canal compromise, sagittal transverse ratio, and presence of vertical lamina fracture. MRI was used to measure the canal encroachment ratio (CER), cross-sectional area of the thecal sac (CSAT), and presence of an epidural hematoma.

RESULTS

Of the 108 patients, 9 (8.3%) had ASIA A, 4 (3.7%) had ASIA B, 17 (15.7%) had ASIA C, 21 (19.4%) had ASIA D, and 57 (52.9%) had ASIA E neurology upon admission. The Thoracolumbar Injury Classification and Severity score (p =0.000), CER (p =0.050), and CSAT (p =0.019) were found to be independently associated with neurological deficits on the multivariate analysis. The receiver operating characteristic curves showed that only CER (area under the curve [AUC], 0.926; 95% confidence interval [CI], 0.860-0.968) and CSAT (AUC, 0.963; 95% CI, 0.908-0.990) had good discriminatory ability, with the optimal cutoff of 50% and 65.3 mm2, respectively.

CONCLUSIONS

Based on the results, the optimal cutoff values of CER >50% and CSAT >65.3 mm2 can predict the incidence of neurological deficits in LLFs.

Care needs of adults with spinal trauma in the prehospital and hospital setting from the perspective of patient care team: A qualitative research

BACKGROUND

Appropriate care of patients with definite spinal cord injury or at risk of it in the prehospital and hospital stages requires comprehensive planning in the health system. It is also the requirement of any successful program to explain the needs from the perspective of its stakeholders. Thus, this study aimed to discover the care needs of adults with spinal trauma in prehospital and hospital settings from the perspective of the patient care team.

MATERIALS AND METHODS

This qualitative study was conducted with the participation of urban and rural prehospital emergency personnel and emergency departments of educational and therapeutic hospitals affiliated to Isfahan, Tehran, Shiraz, Kermanshah, Ahvaz, and Yasuj Universities of Medical Sciences, through conducting 36 in-depth semi-structured interviews from September to December 2021. Using purposive sampling method, the participants were selected considering the maximum variation. The data saturation was reached after conducting interviews and group discussions with 36 subjects. Data were analyzed using conventional content analysis approach. Lundman and Graneheim approach were used for the study rigour. Data were simultaneously analyzed using MAXQDA software version 10.

RESULT

During the data analysis, two themes of prehospital care with two main categories (emergency care and management of secondary complications of spinal trauma) and hospital care with two main categories (emergency care and management of secondary complications of spinal trauma) emerged.

CONCLUSION

Emergency care and management of secondary complications of spinal cord injury in the prehospital and hospital stages can affect treatment results, improve quality of life, and reduce mortality rate, secondary injuries, and healthcare costs. Thus, identification of the care needs of the adults with spinal trauma from the perspective of the patient care team can help the authorities to plan appropriate interventions.

Diffusion Imaging of the Spinal Cord: Clinical Applications

Spinal cord pathologic condition often presents as a neurologic emergency where timely and accurate diagnosis is critical to expedite appropriate treatment and minimize severe morbidity and even mortality. MR imaging is the gold standard imaging technique for diagnosing patients with suspected spinal cord pathologic condition. This review will focus on the basic principles of diffusion imaging and how spinal anatomy presents technical challenges to its application. Both the promises and shortcomings of spinal diffusion imaging will then be explored in the context of several clinical spinal cord pathologies for which diffusion has been evaluated.

Case report: Traumatic hemorrhagic cervical myelopathy in a dog

A 1.5-year-old female entire French bulldog was referred for neurological evaluation, further diagnostic tests, and treatment 24 h after a road traffic accident. Initial emergency treatment, diagnostic tests, and stabilization had been performed by the referring veterinarian. Neurological examination revealed severe spastic non-ambulatory tetraparesis and was consistent with a C1-5 myelopathy. A magnetic resonance imaging (MRI) study revealed an irregular to elongated ovoid intramedullary lesion centered over the body of C2. The lesion showed marked signal heterogeneity with a central T2W and T2* hyperintense region, surrounded by a hypointense rim on both sequences. The lesion appeared heterogeneously T1W hypointense. The lesion was asymmetric (right-sided), affecting both white and gray matter. The C2-3 intervertebral disk appeared moderately degenerate with a Pfirrmann grade of 3. No evidence of vertebral fracture or luxation was found on radiographs or MRI of the vertebral column. Additional soft tissue abnormalities in the area of the right brachial plexus were suggestive of brachial plexus and muscle injury. A diagnosis of traumatic hemorrhagic myelopathy at the level of C2 and concurrent brachial plexus injury was formed. Conservative treatment was elected and consisted of physiotherapy, bladder care with an indwelling urinary catheter, repeated IV methadone based on pain scoring (0.2 mg/kg), oral meloxicam 0.1 mg/kg q24h, and oral gabapentin 10 mg/kg q8h. The dog was discharged after 4 days, with an indwelling urinary catheter and oral medication as described. The catheter was replaced two times by the referring veterinarian and finally removed after 10 days. Thereafter, voluntary urination was seen. During the 2 months after the road traffic accident, slow recovery of motor function was seen. The right thoracic limb recovery progressed more slowly than the left limb, also showing some lower motor neuron signs during follow-up. This was judged to be consistent with a right-sided brachial plexus injury. The dog was reported ambulatory with mild residual ataxia and residual monoparesis of the right thoracic limb at the last follow-up 3 months post-injury. This case report highlights the MRI-based diagnosis of traumatic hemorrhagic myelopathy in a dog. A fair short-term outcome was achieved with conservative treatment in this case.

Ferroptosis in Neurological Disease

Iron accumulation in the CNS occurs in many neurological disorders. It can contribute to neuropathology as iron is a redox-active metal that can generate free radicals. The reasons for the iron buildup in these conditions are varied and depend on which aspects of iron influx, efflux, or sequestration that help maintain iron homeostasis are dysregulated. Iron was shown recently to induce cell death and damage via lipid peroxidation under conditions in which there is deficient glutathione-dependent antioxidant defense. This form of cell death is called ferroptosis. Iron chelation has had limited success in the treatment of neurological disease. There is therefore much interest in ferroptosis as it potentially offers new drugs that could be more effective in reducing iron-mediated lipid peroxidation within the lipid-rich environment of the CNS. In this review, we focus on the molecular mechanisms that induce ferroptosis. We also address how iron enters and leaves the CNS, as well as the evidence for ferroptosis in several neurological disorders. Finally, we highlight biomarkers of ferroptosis and potential therapeutic strategies.

Emergency MRI in Spine Trauma of Children and Adolescents-A Pictorial Review

Severe spinal trauma is uncommon in the pediatric population, but due to the potentially devastating consequences of missed injury, it poses a diagnostic challenge in emergency departments. Diagnostic imaging is often needed to exclude or confirm the injury and to assess its extent. Magnetic resonance imaging (MRI) offers an excellent view of both bony and soft tissue structures and their traumatic findings without exposing children to ionizing radiation. Our pictorial review aims to demonstrate the typical traumatic findings, physiological phenomena, and potential pitfalls of emergency MRI in the trauma of the growing spine.

A critical appraisal of clinical practice guidelines for diagnostic imaging in the spinal cord injury

BACKGROUND CONTEXT

Spinal cord injury (SCI) is a serious health problem which carries a heavy economic burden. Imaging technologies play an important role in the diagnosis of SCI. Although several organizations have developed guidelines for diagnostic imaging of SCI, their quality has not yet been systematically assessed.

PURPOSE

We aim to conduct a systematic review to appraise SCI guidelines and summarize their recommendations for diagnostic imaging of SCI.

STUDY DESIGN

Systematic review.

METHODS

We searched Embase, Medline, Web of Science, Cochrane, some guideline-specific databases (e.g., Scottish Intercollegiate Guidelines Network) and Google Scholar from January 2000 to January 2022. We included guidelines developed by nationally recognized organizations. If multiple versions could be obtained, we included the latest one. We appraised included guidelines using the AGREE II instrument which contains six domains (e.g., scope and purpose). We also extracted recommendations and assessed their supporting evidence using levels of evidence (LOE). The evidence was categorized as A (the best quality), B, C, and D (the worst quality).

RESULTS

Seven guidelines (2008 to 2020) were included. They all received the lowest scores in the domain of applicability. All guidelines (7/7, 100%) recommended magnetic resonance imaging (MRI) in patients with SCI or SCI without radiographic abnormality (SCIWORA). A total of 12 recommendations involving patient age (e.g., adult and child patients), timing of MRI (e.g., as soon as possible and in the acute period), symptoms indicated for MRI (e.g., a stiff spine and midline tenderness, suspected disc and posterior ligamentous complex injury, and neurological deficit), and types of MRI (e.g., T2-weighted imaging and diffusion tensor imaging) were extracted. Among them, the LOE was C in nine (75%) recommendations and D in three (25%) recommendations.

CONCLUSIONS

Seven guidelines were included in the present systematic review, and all of them showed the worst applicability scores in the AGREE II instrument. They all weakly recommended MRI for patients with suspected SCI or SCIWORA based on a low LOE.

Magnetic Resonance Imaging for Spine Emergencies

This article is devoted to the MR imaging evaluation of spine emergencies, defined as spinal pathologic conditions that pose an immediate risk of significant morbidity or mortality to the patient if not diagnosed and treated in a timely manner. MR imaging plays a central role in the timely diagnosis of spine emergencies. A summary of MR imaging indications and MR imaging protocols tailored for a variety of spinal emergencies will be presented followed by a review of key imaging findings for the most-encountered emergent spine pathologic conditions. Pathologic conditions will be broadly grouped into traumatic and atraumatic pathologic conditions. For traumatic injuries, a practical and algorithmic diagnostic approach based on the AO Spine injury classification system will be presented focused on subaxial spine trauma. Atraumatic spinal emergencies will be dichotomized into compressive and noncompressive subtypes. The location of external compressive disease with respect to the thecal sac is fundamental to establishing a differential diagnosis for compressive emergencies, whereas specific patterns of spinal cord involvement on MR imaging will guide the discussion of inflammatory and noninflammatory causes of noncompressive myelopathy.

SV2A PET Imaging Is a Noninvasive Marker for the Detection of Spinal Damage in Experimental Models of Spinal Cord Injury

Traumatic spinal cord injury (SCI) is a neurologic condition characterized by long-term motor and sensory neurologic deficits as a consequence of an external physical impact damaging the spinal cord. Anatomic MRI is considered the gold-standard diagnostic tool to obtain structural information for the prognosis of acute SCI; however, it lacks functional objective information to assess SCI progression and recovery. In this study, we explored the use of synaptic vesicle glycoprotein 2A (SV2A) PET imaging to detect spinal cord lesions noninvasively after SCI. Methods: Mice (n = 7) and rats (n = 8) subjected to unilateral moderate cervical (C5) contusion were euthanized 1 wk after SCI for histologic and autoradiographic (³H-labeled (4R)-1-[(3-methylpyridin-4-yl)methyl]-4-(3,4,5-trifluorophenyl)pyrrolidin-2-one [UCB-J]) investigation of SV2A levels. Longitudinal ¹¹C-UCB-J PET/CT imaging was performed in sham (n = 7) and SCI rats (n = 8) 1 wk and 6 wk after SCI. Animals also underwent an ¹⁸F-FDG PET scan during the latter time point. Postmortem tissue SV2A analysis to corroborate in vivo PET findings was performed 6 wk after SCI. Results: A significant SV2A loss (ranging from -70.3% to -87.3%; P < 0.0001) was measured at the epicenter of the impact in vitro in both mouse and rat contusion SCI models. Longitudinal ¹¹C-UCB-J PET imaging detected SV2A loss in SCI rats (-49.0% ± 8.1% at 1 wk and -52.0% ± 12.9% at 6 wk after SCI), with no change observed in sham rats. In contrast, ¹⁸F-FDG PET imaging measured only subtle hypometabolism (-17.6% ± 14.7%). Finally, postmortem ³H-UCB-J autoradiography correlated with the in vivo SV2A PET findings (r = 0.92, P < 0.0001). Conclusion:¹¹C-UCB-J PET/CT imaging is a noninvasive marker for SV2A loss after SCI. Collectively, these findings indicate that SV2A PET may provide an objective measure of SCI and thus represent a valuable tool to evaluate novel therapeutics. Clinical assessment of SCI with SV2A PET imaging is highly recommended.

Diffusion Tensor Imaging in Spinal Cord Injury: A Review

Magnetic resonance diffusion tensor imaging (DTI) is a recent technique that can measure the direction and magnitude of diffusion of water. It is widely being utilized to evaluate several brain and spinal cord pathologies. The objective of this review is to evaluate the importance of the DTI in patients with spinal cord injury (SCI). It aims to review various articles on DTI SCI and includes both animal and human studies. This will help to describe the current status of the clinical applications of DTI and show its potential as a helpful instrument in clinical practice. The PubMed database was searched for articles relating to the application of DTI in SCI. Relevant articles were also used for the review. A variety of DTI parameters have been studied in various articles. The standard parameters are fractional anisotropy (FA) values, apparent diffusion coefficient (ADC) values, radial diffusivity values, and axial diffusivity values, followed by tractography. FA and ADC values are the most commonly used parameters. The findings observed in most of the studies are increased FA and reduced ADC values following injury to the spinal cord. DTI data metrics possess the potential to become a potent clinical tool in patients with SCI. It is helpful for diagnosis, prognosis, treatment planning, as well as to evaluate the recovery. Nonetheless, to overcome the limitations and determine its reliability clinically, more research has to be performed.

Risk factors and prognosis of spinal cord injury without radiological abnormality in children in China

Background

Compared to adults, spinal cord injury without radiographic abnormality (SCIWORA) is more common in children due to the congenital spinal soft tissue elasticity and immature vertebral bodies. In this study, we aimed to investigate the risk factors and prognosis associated with SCIWORA in China.

Method

We retrospectively examined patient records at the First Hospital of Jilin University from January 2007 to December 2020. Patients diagnosed with SCIWORA were included in the study group (n=16). The age, gender, history of trauma, symptoms, injury level of the spinal cord, the American Spinal Injury Association (ASIA) impairment score according to the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI), as well as laboratory and imaging findings were analyzed.

Result

The study group included 16 patients with SCIWORA with a mean age of 6.69±2.51 y. The ISNCSCI impairment scale was significantly different between the pre-school age patients (≤7 years old) and school age patients (>7 years old) before (P=0.044) and after therapy (P=0.002). Similarly, magnetic resonance imaging demonstrated a significant difference in the spinal injury level between pre-school age and school age patients (P=0.041). Further, the study group was subdivided into three subgroups according to the cause of trauma: Dance, Taekwondo, or Falls. Magnetic resonance imaging revealed significant differences among the three subgroups (P=0.041).

Conclusion

Compared to school-age patients, pre-school-age patients were more vulnerable to SCIWORA with more severe ISNCSCI scores. Dance and Taekwondo are among the risk factors associated with SCIWORA in Chinese children.

Diffusional kurtosis imaging as a possible prognostic marker of cervical incomplete spinal cord injury outcome: a prospective pilot study

BACKGROUND

Spinal cord injury (SCI) is associated with substantial chronic morbidity and mortality. Routine imaging techniques such as T1- and T2-weighted magnetic resonance imaging (MRI) are not effective in predicting neurological deficiency grade or outcome. Diffusional kurtosis imaging (DKI) is an MR imaging technique that provides microstructural information about biological tissue. There are no longitudinal prospective studies assessing DKI metrics in acute traumatic SCI. Therefore, the purpose of this study was to establish a DKI protocol for acute SCI and correlate the DKI metrics to the functional neurological outcome of the patients.

METHODS

Eight consecutive SCI patients referred to our institution with cervical SCI were included in the study. An acute diagnostic MRI scan was supplemented with a novel fast, mean kurtosis DKI protocol, which describes the average deviation from Gaussian diffusional along nine different directions. Mean kurtosis values were measured at the injury site and normalized to the mean kurtosis values of a non-injured site. At discharge form specialized rehabilitation, patients were evaluated using the Spinal Cord Independence Measure-III (SCIM-III). The DKI metrics and SCIM-III were analysed using Spearman's rank correlation.

RESULTS

This pilot study found a significant correlation between decreasing mean kurtosis values at the injury site of the spinal cord and higher grade of disability measured by the SCIM-III (p = 0.002).

CONCLUSION

This pilot study found that DKI may be a valuable tool as a prognostic marker in the acute phase of SCI.

Spinal cord pathology revealed by MRI in traumatic spinal cord injury

PURPOSE OF REVIEW

This review covers recent advances in identifying conventional and quantitative neuroimaging spinal cord biomarkers of lesion severity and remote spinal cord pathology following traumatic spinal cord injury (SCI). It discusses the potential of the most sensitive neuroimaging spinal cord biomarkers to complement clinical workup and improve prediction of recovery.

RECENT FINDINGS

At the injury site, preserved midsagittal tissue bridges - based on conventional sagittal T2-weighted scans - can be identified in the majority of SCI patients; its width being predictive of recovery. Remote from the injury, diffusion indices, and myelin/iron-sensitive neuroimaging-based changes are sensitive to secondary disease processes; its magnitude of change being associated with neurological outcome.

SUMMARY

Neuroimaging biomarkers reveal focal and remote cord pathology. These biomarkers show sensitivity to the underlying disease processes and are clinically eloquent. Thus, they improve injury characterization, enable spatiotemporal tracking of cord pathology, and predict recovery of function following traumatic SCI. Neuroimaging biomarkers, therefore, hold potential to complement the clinical diagnostic workup, improve patient stratification, and can serve as potential endpoints in clinical trials.

Diffusion Tensor Imaging of the Spinal Cord

Spinal cord often is regarded as one of the last territories in the central nervous system where diffusion tensor imaging (DTI) can be used to probe white matter architecture. This article reviews current progress in spinal cord DTI, starting with anatomic properties and technical challenges that make spinal cord DTI a difficult task. Several possibilities offered by advanced pulse sequences that might overcome the difficulties are addressed, with associated trade-offs and limitations. Potential clinical assistance also is discussed in various spinal cord pathologies, such as myelopathy due to external compression, spinal cord tumors, acute ischemia, traumatic injury, and so forth.

Numbers of Axons in Spared Neural Tissue Bridges But Not Their Widths or Areas Correlate With Functional Recovery in Spinal Cord-Injured Rats

The relationships between various parameters of tissue damage and subsequent functional recovery after spinal cord injury (SCI) are not well understood. Patients may regain micturition control and walking despite large postinjury medullar cavities. The objective of this study was to establish possible correlations between morphological findings and degree of functional recovery after spinal cord compression at vertebra Th8 in rats. Recovery of motor (Basso, Beattie, Bresnahan, foot-stepping angle, rump-height index, and ladder climbing), sensory (withdrawal latency), and bladder functions was analyzed at 1, 3, 6, 9, and 12 weeks post-SCI. Following perfusion fixation, spinal cord tissue encompassing the injury site was cut in longitudinal frontal sections. Lesion lengths, lesion volumes, and areas of perilesional neural tissue bridges were determined after staining with cresyl violet. The numbers of axons in these bridges were quantified after staining for class III β-tubulin. We found that it was not the area of the spared tissue bridges, which is routinely determined by magnetic resonance imaging (MRI), but the numbers of axons in them that correlated with functional recovery after SCI (Spearman's ρ > 0.8; p < 0.001). We conclude that prognostic statements based only on MRI measurements should be considered with caution.

Injury classification and level detection of the spinal cord based on the optimized recurrent neural network

Objectives

Spinal cord damage is one of the traumatic situations in persons that may cause the loss of sensation and proper functioning of the muscles either temporarily or permanently. Hence, steps to assure the recovery through the early functioning and precaution could safe-guard a proper interceptive. To ensure the recovery of spinal cord damage through optimized recurrent neural network.

Methods

The research on the spinal cord injury classification and level detection is done using the CT images, which is initially given to the segmentation that is done using the adaptive thresholding methodology. Once the segments are formed, the disc is localized using the sparse fuzzy C-means clustering approach. In the next step, the features are extracted from the localized disc and the features include the connectivity features, statistical features, image-level features, grid-level features, Histogram of Oriented Gradients (HOG), and Linear Gradient Pattern (LGP). Then, the injury detection is done based on the Crow search Rider Optimization algorithm-based Deep Convolutional Neural Network (CS-ROA-based DCNN). Once the result regarding the presence of the injury is obtained, the injury-level classification is done based on the proposed Deep Recurrent Neural Network (Deep RNN), and in case of the absence of injury, the process is terminated. Therefore, the injury detection classifier derives the level of the injury, such as normal, wedge, biconcavity, and crush.

Results

The experimentation is carried out using an Osteoporotic vertebral fractures database. The performance of the injury level detection based on the proposed model is evaluated based on accuracy, sensitivity, and specificity. The proposed model achieves the maximal accuracy of 0.895, maximal sensitivity of 0.871, and the maximal specificity of 0.933 with respect to K-Fold.

Conclusions

The experimental results show that the proposed model is better than the existing models in terms of accuracy, sensitivity, and specificity.

Relationship between Machine-Learning Image Classification of T2-Weighted Intramedullary Hypointensity on 3 Tesla Magnetic Resonance Imaging and Clinical Outcome in Dogs with Severe Spinal Cord Injury

Early prognostic information in cases of severe spinal cord injury can aid treatment planning and stratification for clinical trials. Analysis of intraparenchymal signal change on magnetic resonance imaging has been suggested to inform outcome prediction in traumatic spinal cord injury. We hypothesized that intraparenchymal T₂-weighted hypointensity would be associated with a lower potential for functional recovery and a higher risk of progressive neurological deterioration in dogs with acute, severe, naturally occurring spinal cord injury. Our objectives were to: 1) demonstrate capacity for machine-learning criteria to identify clinically relevant regions of hypointensity and 2) compare clinical outcomes for cases with and without such regions. A total of 95 dogs with complete spinal cord injury were evaluated. An image classification system, based on Speeded-Up Robust Features (SURF), was trained to recognize individual axial T₂-weighted slices that contained hypointensity. The presence of such slices in a given transverse series was correlated with a lower chance of functional recovery (odds ratio [OR], 0.08; confidence interval [CI], 0.02-0.38; p < 10^-3) and with a higher risk of neurological deterioration (OR, 0.14; 95% CI, 0.05-0.42; p < 10^-3). Identification of intraparenchymal T₂-weighted hypointensity in severe, naturally occurring spinal cord injury may be assisted by an image classification tool and is correlated with functional recovery.

Injury volume extracted from MRI predicts neurologic outcome in acute spinal cord injury: A prospective TRACK-SCI pilot study

Conventional MRI measures of traumatic spinal cord injury severity largely rely on 2-dimensional injury characteristics such as intramedullary lesion length and cord compression. Recent advances in spinal cord (SC) analysis have led to the development of a robust anatomic atlas incorporated into an open-source platform called the Spinal Cord Toolbox (SCT) that allows for quantitative volumetric injury analysis. In the current study, we evaluate the prognostic value of volumetric measures of spinal cord injury on MRI following registration of T2-weighted (T2w) images and segmented lesions from acute SCI patients with a standardized atlas. This IRB-approved prospective cohort study involved the image analysis of 60 blunt cervical SCI patients enrolled in the TRACK-SCI clinical research protocol. Axial T2w MRI data obtained within 24 h of injury were processed using the SCT. Briefly, SC MRIs were automatically segmented using the sct_deepseg_sc tool in the SCT and segmentations were manually corrected by a neuro-radiologist. Lesion volume data were used as predictor variables for correlation with lower extremity motor scores at discharge. Volumetric MRI measures of T2w signal abnormality comprising the SCI lesion accurately predict lower extremity motor scores at time of patient discharge. Similarly, MRI measures of injury volume significantly correlated with motor scores to a greater degree than conventional 2-D metrics of lesion size. The volume of total injury and of injured spinal cord motor regions on T2w MRI is significantly and independently associated with neurologic outcome at discharge after injury.

Predictive Value of Midsagittal Tissue Bridges on Functional Recovery After Spinal Cord Injury

Background

The majority of patients with spinal cord injury (SCI) have anatomically incomplete lesions and present with preserved tissue bridges, yet their outcomes vary.

Objective

To assess the predictive value of the anatomical location (ventral/dorsal) and width of preserved midsagittal tissue bridges for American Spinal Injury Association (ASIA) Impairment Scale (AIS) grade conversion and SCI patient stratification into recovery-specific subgroups.

Methods

This retrospective longitudinal study includes 70 patients (56 men, age: 52.36 ± 18.58 years) with subacute (ie, 1 month) SCI (45 tetraplegics, 25 paraplegics), 1-month neuroimaging data, and 1-month and 12-month clinical data. One-month midsagittal T2-weighted scans were used to determine the location and width of tissue bridges. Their associations with functional outcomes were assessed using partial correlation and unbiased recursive partitioning conditional inference tree (URP-CTREE).

Results

Fifty-seven (81.4%) of 70 patients had tissue bridges (2.53 ± 2.04 mm) at 1-month post-SCI. Larger ventral (P = .001, r = 0.511) and dorsal (P < .001, r = 0.546) tissue bridges were associated with higher AIS conversion rates 12 months post-SCI (n = 39). URP-CTREE analysis identified 1-month ventral tissue bridges as predictors of 12-month total motor scores (0.4 mm cutoff, P = .008), recovery of upper extremity motor scores at 12 months (1.82 mm cutoff, P = .002), 12-month pin-prick scores (1.4 mm cutoff, P = .018), and dorsal tissue bridges at 1 month as predictors of 12-month Spinal Cord Independence Measure scores (0.5 mm cutoff, P = .003).

Conclusions

Midsagittal tissue bridges add predictive value to baseline clinical measures for post-SCI recovery. Based on tissue bridges’ width, patients can be classified into subgroups of clinical recovery profiles. Midsagittal tissue bridges provide means to optimize patient stratification in clinical trials.

Trends in Rates of ASIA Impairment Scale Conversion in Traumatic Complete Spinal Cord Injury

Recent studies of persons with spinal cord injury (SCI) report higher conversion rates of the American Spinal Injury Association (ASIA) Impairment Scale (AIS) grades, especially for complete injuries. We examined the rate of conversion over time after complete SCI, accounting for demographic and injury characteristics. Subjects were 16 years of age and older with a complete SCI injury between 1995 and 2015, enrolled in the National SCI Database as day-1 admissions. We grouped subjects into 3-year intervals and assessed trends in conversion for the total sample and by tetraplegia (Tetra), high paraplegia (levels T1–9, HPara), and low paraplegia (levels T10–12, LPara).We used logistic regression to identify factors related to conversion such as age, sex, etiology, and level of injury. Of 2036 subjects, 1876 subjects had a follow-up examination between 30 and 730 days post-injury. Average age at injury was 34.2 ± 14.6 years; 79.8% were male, 44.6% Tetra, 35.3% HPara, and 20.1% LPara. There was a strong trend toward increased rates of conversion over time (p < 0.01 for all groups), especially for Tetra (to incomplete from 17.6% in 1995–1997 to 50% in 2013–2015, and to motor incomplete from 9.4% to 28.1%). Conversion rates for Para were less dramatic. There were increased odds of converting to incomplete for year of injury, level of injury (Tetra >LPara >HPara), non-violent etiology, and age (older is better). We found similar factors for conversion to motor incomplete, except sex was significant and etiology was not. Conversion rates from complete to incomplete and motor incomplete injury have been increasing, particularly for persons with tetraplegia. This has implications for acute clinical trials and for prognostication early after SCI.

Radiological Risk Factors for Neurological Deficits After Traumatic Mid and Low Lumbar Fractures

STUDY DESIGN

Retrospective study.

OBJECTIVE

We identified radiological risk factors for neurological deficits in mid and low lumbar spinal fractures.

SUMMARY OF BACKGROUND DATA

Although numerous studies have focused on radiological risk factors for neurological deficits in spinal cord injury or thoracolumbar junction area fractures, few have examined mid and low lumbar fractures at the cauda equina level.

METHODS

We retrospectively reviewed 71 consecutive patients who suffered acute traumatic mid and low lumbar fractures (L2-L5) corresponding to the cauda equina level, as confirmed on magnetic resonance imaging. We defined a neurological deficit as present if the patient had any sensory or motor deficit in the lower extremity or autonomic system at the initial assessment. Various computed tomography parameters of canal stenosis, vertebral body compression, sagittal alignment, interpedicular distance, and presence of vertical laminar fractures were analyzed as independent risk factors to predict neurological deficits using multivariate logistic regression analyses.

RESULTS

At the initial assessment, 31 patients had neurological deficits. Fracture level, AO fracture type, canal encroachment ratio, vertebral compression ratio, interpedicular distance ratio, and presence of a vertical laminar fracture were significantly associated with the presence of neurological deficits (all P < 0.05). Multivariate logistic regression identified fracture level, canal encroachment ratio (adjusted odds ratio [aOR] 1.072, 95% confidence interval [CI] 1.018-1.129), and vertebral compression ratio (aOR 0.884, 95% CI 0.788-0.992) as independent predictors of a neurological deficit. Receiver operating characteristic curve analyses revealed that only the canal encroachment ratio had good discriminatory ability (area under the curve 0.874, 95% CI 0.791-0.957), and the optimal cutoff was 47% (canal diameter 6.6 mm) with 90.3% sensitivity and 80% specificity.

CONCLUSION

The canal encroachment ratio was most strongly associated with neurological deficits in traumatic mid and low lumbar fractures, with an optimal cutoff of 47%.

LEVEL OF EVIDENCE

4.

Spinal Cord Imaging Markers and Recovery of Volitional Leg Movement With Spinal Cord Epidural Stimulation in Individuals With Clinically Motor Complete Spinal Cord Injury

Previous studies have shown that epidural stimulation of the lumbosacral spinal cord (scES) can re-enable lower limb volitional motor control in individuals with chronic, clinically motor complete spinal cord injury (SCI). This observation entails that residual supraspinal connectivity to the lumbosacral spinal circuitry still persisted after SCI, although it was non-detectable when scES was not provided. In the present study, we aimed at exploring further the mechanisms underlying scES-promoted recovery of volitional lower limb motor control by investigating neuroimaging markers at the spinal cord lesion site via magnetic resonance imaging (MRI). Spinal cord MRI was collected prior to epidural stimulator implantation in 13 individuals with chronic, clinically motor complete SCI, and the spared tissue of specific regions of the spinal cord (anterior, posterior, right, left, and total cord) was assessed. After epidural stimulator implantation, and prior to any training, volitional motor control was evaluated during left and right lower limb flexion and ankle dorsiflexion attempts. The ability to generate force exertion and movement was not correlated to any neuroimaging marker. On the other hand, spared tissue of specific cord regions significantly and importantly correlated with some aspects of motor control that include activation amplitude of antagonist (negative correlation) muscles during left ankle dorsiflexion, and electromyographic coordination patterns during right lower limb flexion. The fact that amount and location of spared spinal cord tissue at the lesion site were not related to the ability to generate volitional lower limb movements may suggest that supraspinal inputs through spared spinal cord regions that differ across individuals can result in the generation of lower limb volitional motor output prior to any training when epidural stimulation is provided.

Modulation of inflammatory factors predicts the outcome following spinal cord injury

BACKGROUND

The correlation between inflammatory responses caused by spinal cord injury (SCI) and the prognosis of patients with SCI still remains controversial.

METHODS

In the present study, we preliminary investigated the serum levels of interleukin (IL)-4, IL-10, major histocompatibility complex (MHC)-I, and inducible nitric oxide synthase (iNOS) and compared the serum IL-4 and IL-10 expression in rats of high Basso-Beattie-Bresnahan (BBB) scores with these of low BBB scores. Besides, the infiltration of macrophage and the axonal regeneration of the injured spinal cord were observed from day 10 to day 30.

RESULTS

We found that higher serum levels of IL-4 and IL-10 can reflect the restorability degree of SCI and could be potential biomarkers for the prognosis of SCI. The infiltration of the M2 subtype of macrophage and the axons regrowth might contribute to a better prognosis.

CONCLUSIONS

The current study demonstrates that the serum levels of IL-4 and IL-10 are preliminarily adopted as serologic markers to forecast SCI, and high serum levels of IL-4 and IL-10 may indicate a better prognosis. Moreover, the way to promote macrophage polarization from M1 to M2 may contribute to better axonal regeneration.

Evolution of Magnetic Resonance Imaging as Predictors and Correlates of Functional Outcome after Spinal Cord Contusion Injury in the Rat

Clinical methods for determining the severity of traumatic spinal cord injury (SCI) and long-term functional outcome in the acute setting are limited in their prognostic accuracy because of the heterogeneity of injury and dynamic injury progression. The aim of this study was to evaluate the time course and sensitivity of advanced magnetic resonance imaging (MRI) methods to neurological function after SCI in a rat contusion model. Rats received a graded contusion injury at T10 using a weight-drop apparatus. MRI consisted of morphological measures from T₂-weighted imaging, quantitative T₂ imaging, and diffusion-weighted imaging (DWI) at 1, 30, and 90 days post-injury (dpi). The derived metrics were compared with neurological function assessed using weekly Basso, Beattie, and Bresnahan (BBB) locomotor scoring and return of reflexive micturition function. At the acute time point (1 dpi), diffusion metrics sensitive to axonal injury at the injury epicenter had the strongest correlation with time-matched BBB scores and best predicted 90-dpi BBB scores. At 30 dpi, axonal water fraction derived from DWI and T₂ values were both correlated with time-matched locomotor scores. At the chronic time point (90 dpi), cross-sectional area was most closely correlated to BBB. Overall, the results demonstrate differential sensitivity of MRI metrics at different time points after injury, but the metrics follow the expected pathology of acute axonal injury followed by continued degeneration and finally a terminal level of atrophy. Specificity of DWI in the acute setting may make it impactful as a prognostic tool while T₂ imaging provided the most information about injury severity in chronic injury.

Practical Application of Recent Advances in Diagnostic, Prognostic, and Therapeutic Modalities for Spinal Cord Injury

OBJECTIVE

Spinal cord injury remains a highly morbid entity, with limited treatment modalities in both acute and chronic settings. Clinical research efforts to improve therapeutic guidelines are confounded by initial evaluation inaccuracies, as presentations are frequently complicated by trauma and objective diagnostic and prognostic methods are poorly defined. The purpose of our study was to review recent practical advances for further delineation of these injuries and how such classification may benefit the development of novel treatments.

METHODS

A review was carried out of recent studies reported within the last 5 years for prognostic and diagnostic modalities of acute spinal cord injury.

RESULTS

Substantial efforts have been made to improve the timeliness and accuracy of the initial assessment, not only for the purpose of enhancing prognostication but also in determining the efficacy of new treatments. Whether it be applying traumatic brain injury principles to limit injury extent, external stimulators used for chronic pain conditions to enhance the effects of physical therapy, or creative algorithms incorporating various nerve or muscle transfer techniques, innovative and practical solutions continue to be developed in lieu of definitive treatment. Further development will benefit from enhanced stratification of injury from accurate and practical assessment modalities.

CONCLUSIONS

Recent advances in accurate, timely, and practical classification methods of acute spinal cord injury will assist in the development of novel treatment approaches for both acute and chronic injury alike.

Modern Medical Management of Spinal Cord Injury

PURPOSE OF REVIEW

Spinal cord injury (SCI) shows an incidence of 10.4-83 cases/million/year globally and remains a significant source of morbidity and cost to society. Despite greater understanding of the pathophysiology of SCI, neuroprotective and regenerative approaches to treatment have had limited clinical utility to date. Here, we review the key components of supportive care that are thus the mainstay of therapy and that have improved outcomes for victims of acute SCI in recent decades.

RECENT STUDIES

Current management strategies for acute SCI involve early surgical decompression and fixation, the use of vasopressor medications for mean arterial blood pressure (MAP) augmentation to improve spinal cord perfusion, and corticosteroids. We highlight recent literature supporting the role of norepinephrine in acute SCI management and also an emerging neurocritical care strategy that seeks to optimize spinal cord perfusion pressure with the assistance of invasive monitoring. This review will highlight key pathophysiologic principles and targets for current acute clinical treatments in SCI, which include early surgical decompression, MAP augmentation, and corticosteroids. We discuss anticipated future research in these areas and focus on potential risks inherent to these treatments.