Protracted Morphological Changes in the Corticospinal Tract Within the Cervical Spinal Cord After Intracerebral Hemorrhage in the Right Striatum of Mice

This study aimed to reveal functional and morphological changes in the corticospinal tract, a pathway shown to be susceptible to diabetes. Type 1 diabetes was induced in 13-week-old male Wistar rats administered streptozotocin. Twenty-three weeks after streptozotocin injection, diabetic animals and age-matched control animals were used to demonstrate the conduction velocity of the corticospinal tract. Other animals were used for morphometric analyses of the base of the dorsal funiculus of the corticospinal tract in the spinal cord using both optical and electron microscopy. The conduction velocity of the corticospinal tract decreased in the lumbar spinal cord in the diabetic animal, although it did not decrease in the cervical spinal cord. Furthermore, atrophy of the fibers of the base of the dorsal funiculus was observed along their entire length, with an increase in the g-ratio in the lumbar spinal cord in the diabetic animal. This study indicates that the corticospinal tract fibers projecting to the lumbar spinal cord experience a decrease in conduction velocity at the lumbar spinal cord of these axons in diabetic animals, likely caused by a combination of axonal atrophy and an increased g-ratio due to thinning of the myelin sheath.

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White matter changes in corticospinal tract associated with improvement in arm and hand functions in incomplete cervical spinal cord injury: pilot case series

Spinal Cord Series and Cases ◽

10.1038/scsandc.2017.28 ◽

2017 ◽

Vol 3 (1) ◽

Cited By ~ 3

Author(s):

Nuray Yozbatiran ◽

Zafer Keser ◽

Khader Hasan ◽

Argyrios Stampas ◽

Radha Korupolu ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

White Matter ◽

Corticospinal Tract ◽

Cervical Spinal Cord ◽

Case Series ◽

Cervical Spinal Cord Injury ◽

White Matter Changes ◽

Hand Functions ◽

Cord Injury

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A critical reappraisal of corticospinal tract somatotopy and its role in traumatic cervical spinal cord syndromes

Journal of Neurosurgery Spine ◽

10.3171/2021.7.spine21546 ◽

2021 ◽

pp. 1-7

Author(s):

Allan D. Levi ◽

Jan M. Schwab

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Upper Extremity ◽

Corticospinal Tract ◽

Cervical Spinal Cord ◽

Hand Function ◽

Cervical Spinal Cord Injury ◽

Pathophysiological Mechanism ◽

Cord Injury ◽

Central Cord Syndrome

The corticospinal tract (CST) is the preeminent voluntary motor pathway that controls human movements. Consequently, long-standing interest has focused on CST location and function in order to understand both loss and recovery of neurological function after incomplete cervical spinal cord injury, such as traumatic central cord syndrome. The hallmark clinical finding is paresis of the hands and upper-extremity function with retention of lower-extremity movements, which has been attributed to injury and the sparing of specific CST fibers. In contrast to historical concepts that proposed somatotopic (laminar) CST organization, the current narrative summarizes the accumulated evidence that 1) there is no somatotopic organization of the corticospinal tract within the spinal cord in humans and 2) the CST is critically important for hand function. The evidence includes data from 1) tract-tracing studies of the central nervous system and in vivo MRI studies of both humans and nonhuman primates, 2) selective ablative studies of the CST in primates, 3) evolutionary assessments of the CST in mammals, and 4) neuropathological examinations of patients after incomplete cervical spinal cord injury involving the CST and prominent arm and hand dysfunction. Acute traumatic central cord syndrome is characterized by prominent upper-extremity dysfunction, which has been falsely predicated on pinpoint injury to an assumed CST layer that specifically innervates the hand muscles. Given the evidence surveyed herein, the pathophysiological mechanism is most likely related to diffuse injury to the CST that plays a critically important role in hand function.

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Segmental analysis in cervical spinal cord injury reveals the recovery potential of hand muscles with preserved corticospinal tract: Insights beyond impairment scales

10.1101/2021.11.30.21265051 ◽

2021 ◽

Author(s):

Gustavo Balbinot ◽

Guijin Li ◽

Sukhvinder Kalsi-Ryan ◽

Rainer Abel ◽

Doris Maier ◽

...

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Muscle Strength ◽

Evoked Potentials ◽

Corticospinal Tract ◽

Cervical Spinal Cord ◽

Hand Muscles ◽

Recovery Potential ◽

Strength Recovery ◽

Cord Injury

Cervical spinal cord injury (SCI) severely impacts widespread bodily functions with extensive impairments for individuals, who prioritize regaining hand function. Although prior work has focused on the recovery at the person-level, the factors determining the recovery potential of individual muscles are poorly understood. There is a need for changing this paradigm in the field by moving beyond person-level classification of residual strength and sacral sparing to a muscle-specific analysis with a focus on the role of corticospinal tract (CST) sparing. The most striking part of human evolution involved the development of dextrous hand use with a respective expansion of the sensorimotor cortex controlling hand movements, which, because of the extensive CST projections, may constitute a drawback after SCI. Here, we investigated the muscle-specific natural recovery after cervical SCI in 748 patients from the European Multicenter Study about SCI (EMSCI), one of the largest datasets analysed to date. All participants were assessed within the first 4 weeks after SCI and re-assessed at 12, 24, and 48 weeks. Subsets of individuals underwent electrophysiological multimodal evaluations to discern CST and lower motor neuron (LMN) integrity [motor evoked potentials (MEP): N = 203; somatosensory evoked potentials (SSEP): N = 313; nerve conduction studies (NCS): N = 280]. We show the first evidence of the importance of CST sparing for proportional recovery in SCI, which is known in stroke survivors to represent the biological limits of structural and functional plasticity. In AIS D, baseline strength is a good predictor of segmental muscle strength recovery, while the proportionality in relation to baseline strength is lower for AIS B/C and breaks for AIS A. More severely impaired individuals showed non-linear and more variable recovery profiles, especially for hand muscles, while measures of CST sparing (by means of MEP) improved the prediction of hand muscle strength recovery. Therefore, assessment strategies for muscle-specific motor recovery in acute SCI improve by accounting for CST sparing and complement gross person-level predictions. The latter is of paramount importance for clinical trial outcomes and to target neurorehabilitation of upper limb function, where any single muscle function impacts the outcome of independence in cervical SCI.

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Spinal cord representation of motor cortex plasticity reflects corticospinal tract LTP

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2113192118 ◽

2021 ◽

Vol 118 (52) ◽

pp. e2113192118

Author(s):

Alzahraa Amer ◽

Jianxun Xia ◽

Michael Smith ◽

John H. Martin

Keyword(s):

Spinal Cord ◽

Motor Cortex ◽

Corticospinal Tract ◽

Cervical Spinal Cord ◽

Long Term Potentiation ◽

Dependent Manner ◽

Term Potentiation ◽

Spinal Cord Segment ◽

Spinal Interneuron ◽

Activity Dependent

Although it is well known that activity-dependent motor cortex (MCX) plasticity produces long-term potentiation (LTP) of local cortical circuits, leading to enhanced muscle function, the effects on the corticospinal projection to spinal neurons has not yet been thoroughly studied. Here, we investigate a spinal locus for corticospinal tract (CST) plasticity in anesthetized rats using multichannel recording of motor-evoked, intraspinal local field potentials (LFPs) at the sixth cervical spinal cord segment. We produced LTP by intermittent theta burst electrical stimulation (iTBS) of the wrist area of MCX. Approximately 3 min of MCX iTBS potentiated the monosynaptic excitatory LFP recorded within the CST termination field in the dorsal horn and intermediate zone for at least 15 min after stimulation. Ventrolaterally, in the spinal cord gray matter, which is outside the CST termination field in rats, iTBS potentiated an oligosynaptic negative LFP that was localized to the wrist muscle motor pool. Spinal LTP remained robust, despite pharmacological blockade of iTBS-induced LTP within MCX using MK801, showing that activity-dependent spinal plasticity can be induced without concurrent MCX LTP. Pyramidal tract iTBS, which preferentially activates the CST, also produced significant spinal LTP, indicating the capacity for plasticity at the CST–spinal interneuron synapse. Our findings show CST monosynaptic LTP in spinal interneurons and demonstrate that spinal premotor circuits are capable of further modifying descending MCX control signals in an activity-dependent manner.

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Neuromyelitis Optica in a Nepalese Man

Case Reports in Neurological Medicine ◽

10.1155/2017/8596781 ◽

2017 ◽

Vol 2017 ◽

pp. 1-4

Author(s):

Yogesh Subedi ◽

Utsav Joshi ◽

Sanjeeb Sudarshan Bhandari ◽

Ashbina Pokharel ◽

Ashbita Pokharel

Keyword(s):

Spinal Cord ◽

Neuromyelitis Optica ◽

Immunoglobulin G ◽

Cervical Spinal Cord ◽

Immunosuppressive Treatment ◽

Lower Limbs ◽

Inflammatory Disorder ◽

Hyperintense Signal ◽

Muscle Groups ◽

The Right

Background. Neuromyelitis optica is a severely disabling inflammatory disorder of the central nervous system of autoimmune etiology that mainly affects the optic nerves and spinal cord. Here, we present a case report detailing a patient with tingling and weakness of right upper and lower limbs who was neuromyelitis optica immunoglobulin G-positive. Case Presentation. A 46-year-old Nepalese man presented to the hospital with a history of tingling and weakness of right upper and lower limbs that developed over a period of two months. Clinical evaluation showed diminished power across all major muscle groups in the right upper and lower limbs. Magnetic resonance imaging of his cervical spine showed T1 iso- to hypointense signal and T2 hyperintense signal in central cervical spinal cord from first to sixth cervical level, probably suggestive of myelitis or demyelination. The patient was immediately started on intravenous methylprednisolone. The diagnosis of neuromyelitis optica was later confirmed with strongly positive neuromyelitis optica immunoglobulin G. Conclusion. In resource limited setting, in the absence of tests for neuromyelitis optica immunoglobulin G, treatment was started and the patient’s condition started to get better. Hence, early initiation of aggressive immunosuppressive treatment is essential in such cases.

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Wallerian degeneration in cervical spinal cord tracts is commonly seen in routine T2-weighted MRI after traumatic spinal cord injury and is associated with impairment in a retrospective study

European Radiology ◽

10.1007/s00330-020-07388-2 ◽

2020 ◽

Author(s):

Tim Fischer ◽

Christoph Stern ◽

Patrick Freund ◽

Martin Schubert ◽

Reto Sutter

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Wallerian Degeneration ◽

Evoked Potential ◽

Corticospinal Tract ◽

Cervical Spinal Cord ◽

Dorsal Column ◽

Traumatic Spinal Cord Injury ◽

Spinothalamic Tract ◽

Cord Injury

Abstract Objectives Wallerian degeneration (WD) is a well-known process after nerve injury. In this study, occurrence of remote intramedullary signal changes, consistent with WD, and its correlation with clinical and neurophysiological impairment were assessed after traumatic spinal cord injury (tSCI). Methods In 35 patients with tSCI, WD was evaluated by two radiologists on T2-weighted images of serial routine MRI examinations of the cervical spine. Dorsal column (DC), lateral corticospinal tract (CS), and lateral spinothalamic tract (ST) were the analyzed anatomical regions. Impairment scoring according to the American Spinal Injury Association Impairment Scale (AIS, A–D) as well as a scoring system (0–4 points) for motor evoked potential (MEP) and sensory evoked potential (SEP) was included. Mann-Whitney U test was used to test for differences. Results WD in the DC occurred in 71.4% (n = 25), in the CS in 57.1% (n = 20), and in 37.1% (n = 13) in the ST. With WD present, AIS grades were worse for all tracts. DC: median AIS B vs D, p < 0.001; CS: B vs D, p = 0.016; and ST: B vs D, p = 0.015. More pathological MEP scores correlated with WD in the DC (median score 0 vs 3, p < 0.001) and in the CS (0 vs 2, p = 0.032). SEP scores were lower with WD in the DC only (1 vs 2, p = 0.031). Conclusions WD can be detected on T2-weighted scans in the majority of cervical spinal cord injury patients and should be considered as a direct effect of the trauma. When observed, it is associated with higher degree of impairment. Key Points • Wallerian degeneration is commonly seen in routine MRI after traumatic spinal cord injury. • Wallerian degeneration is visible in the anatomical regions of the dorsal column, the lateral corticospinal tract, and the lateral spinothalamic tract. • Presence of Wallerian degeneration is associated with higher degree of impairment.

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The arterial blood supply to the cervical spinal cord in European hare

Biologia ◽

10.1515/biolog-2015-0038 ◽

2015 ◽

Vol 70 (3) ◽

Author(s):

David Mazensky ◽

Slavka Flesarova

Keyword(s):

Spinal Cord ◽

Blood Supply ◽

Cervical Spinal Cord ◽

Cervical Region ◽

Corrosion Casting ◽

European Hare ◽

Arterial Blood Supply ◽

Arterial Blood ◽

The Right ◽

Dissection Technique

AbstractThe aim of this study was to describe the arterial arrangement of the cervical spinal cord in hare. The study was carried out on 20 adult European hares. Ten hares were used in the corrosion technique and ten hares in the dissection technique. After the killing, the vascular network was perfused with saline. Batson’s corrosion casting kit no. 17 © was used as a casting medium. After polymerisation of the medium, in ten hares the maceration was carried out in KOH solution, and in ten other hares formaldehyde was injected by the dissection technique into the vertebral canal. We found high variability in blood supply of the cervical spinal cord. The origin of the ventral spinal artery from the right vertebral artery was found on average in 65 % of the cases and from the anastomosis of two ventral spinal arteries was found on average in 35% of the cases. The presence of ventral branches of spinal branches entering the ventral spinal artery in the cervical region was observed in 37.9% of the cases on the right side and in 62.1% of the cases on the left side. The presence of dorsal branches of spinal branches was observed in 66.2% of the cases on the left side and in 33.8% of the cases on the right side.

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Vertebrobasilar System in the European Hare

Folia Veterinaria ◽

10.1515/fv-2016-0013 ◽

2016 ◽

Vol 60 (2) ◽

pp. 20-23

Author(s):

S. Flešárová ◽

D. Maženský

Keyword(s):

Spinal Cord ◽

Vertebral Artery ◽

Cervical Spinal Cord ◽

High Variability ◽

Arterial System ◽

Corrosion Casting ◽

European Hare ◽

Vertebral Arteries ◽

Vertebrobasilar System ◽

The Right

Abstract The aim of this study was to describe the arterial arrangement of the cervical spinal cord in the hare using the corrosion technique. The study was carried out on 10 adult European hares (Lepus Europeus). The arterial system of the cervical spinal cord was injected using Batson’s corrosion casting kit No. 17. The fusion of the bilateral vertebral arteries was found in 70% of the cases without a connecting branch and in 30% of the cases with one connecting branch just posterior to the fusion. The ventral spinal artery was in connection with the right vertebral artery in 60% of the cases and by means of an anastomosis of two spinal branches arising from the bilateral vertebral arteries in 40% of the cases. Based on the results of this study, it is possible to conclude that there is a high variability of the blood supply to the cervical part of the spinal cord in the hare.

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Case Report: Efficacy of Rituximab in a Patient With Familial Mediterranean Fever and Multiple Sclerosis

Frontiers in Neurology ◽

10.3389/fneur.2020.591395 ◽

2021 ◽

Vol 11 ◽

Author(s):

Mattia Pozzato ◽

Emanuele Micaglio ◽

Chiara Starvaggi Cucuzza ◽

Alessandro Cagol ◽

Daniela Galimberti ◽

...

Keyword(s):

Multiple Sclerosis ◽

Spinal Cord ◽

Familial Mediterranean Fever ◽

Demyelinating Disease ◽

Cervical Spinal Cord ◽

Mefv Gene ◽

The Body ◽

Drug Choice ◽

Mediterranean Fever ◽

The Right

Familial Mediterranean Fever (FMF) is a genetic autoinflammatory disease characterized by recurrent episodes of fever and serositis caused by mutations in the MEFV gene, while Multiple Sclerosis (MS) is an inflammatory demyelinating disease of the CNS with genetic and environmental etiology. The two diseases rarely occur in association with relevant implications for clinical management and drug choice. In this paper, we present the case of a 53-year-old male with an autosomal dominant FMF since childhood who presented acute paresthesia at the right part of the body. He performed a brain and spinal cord MRI, which showed multiple brain lesions and a gd-enhancing lesion in the cervical spinal cord, and then received a diagnosis of MS. He then started Interferonβ-1a which was effective but not tolerated and caused hepatotoxicity, and then shifted to Rituximab with 3-month clinical and neuroradiological efficacy.

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