Longitudinal three-dimensional-T2WI-SPACE study on wallerian degeneration in cat corticospinal tract and underlying pathology changes

2015 ◽  
Vol 42 (4) ◽  
pp. 1134-1143
Author(s):  
Min Zhang ◽  
Wen Qin ◽  
Yueshan Piao ◽  
Deyu Guo ◽  
Zixin Zhu ◽  
...  
BMC Neurology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Bing Bao ◽  
Xiangbin Wu ◽  
Zhongbin Xia ◽  
Yaoyao Shen

Abstract Background Wallerian degeneration (WD) can occur in different projecting systems, such as corticospinal tract, dentate-rubro-olivary pathway, and corticopontocerebellar tract. However, the co-occurrence of hypertrophic olivary degeneration (HOD) and middle cerebellar peduncles (MCPs) degeneration secondary to unilateral pontine infarction in a single patient is extremely rare. Case presentation A 71-year-old man presented with acute onset of dizzness, slurred speech, and right-sided weakness. On the next day, his previous neurologic deficits deteriorated. Brain magnetic resonance imaging (MRI) revealed acute ischemic stroke of the left pons. After treatment with thrombolysis, antiplatelets, and rehabilitation training, his speaking and motor function improved moderately. At the 3-month follow-up, the MRI showed hyperintensity in the left medulla oblongata and bilateral MCPs on T2-weighted and FLAIR images, suggesting HOD as well as MCPs degeneration. Conclusions It is of great importance for us to know the anatomic knowledge of dentate-rubro-olivary and corticopontocerebellar pathways.


Author(s):  
Tim Fischer ◽  
Christoph Stern ◽  
Patrick Freund ◽  
Martin Schubert ◽  
Reto Sutter

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.


2004 ◽  
Vol 100 (1) ◽  
pp. 56-60 ◽  
Author(s):  
Toru Watanabe ◽  
Yoshiho Honda ◽  
Yukihiko Fujii ◽  
Miyako Koyama ◽  
Ryuichi Tanaka

Object. The purposes of this study were to evaluate the serial changes in diffusion anisotropy of the brain, probably reflecting axonal function in brain-dead patients, and thus to explore the possibility of quantitatively estimating the risk of brain death. Methods. Ten patients suffering from stroke with or without impending brain death and 10 healthy volunteers were studied using three-dimensional anisotropy contrast (3DAC) magnetic resonance (MR) axonography with the aid of a 1.5-tesla MR imaging system. To detect changes in the diffusion anisotropy of neural bundles, the corticospinal tract was evaluated. Diffusion anisotropy of short axonal fibers decreased immediately after apparent brain death. Whereas the trichromatic coefficients of the corticospinal tract greatly diminished between 6 and 12 hours after apparent brain death, the coefficients of the corpus callosum and the optic radiation decreased in less time, that is, between 1 and 6 hours. The coefficients of these three bundles turned isotropic between 24 and 44 hours after apparent brain death. Conclusions. Results of 3DAC MR axonography revealed that diffusion anisotropy of neural bundles diminished between 1 and 12 hours after the onset of apparent brain death, probably depending on the length of the bundles, and disappeared between 24 and 44 hours after the onset of brain death, which might reflect dynamic changes of axonal structure and indirectly herald axonal dysfunction. These findings seem to be greatly helpful in establishing an appropriate method to estimate the risk of brain death quantitatively and in forming the basis of future definitions of brain death.


Neurographics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 111-126
Author(s):  
F.B. Assunção ◽  
T.L.P.D. Scoppetta ◽  
B.S. Yonekura Inada ◽  
L.D.A. Martins ◽  
E.O Narvaez ◽  
...  

CNS WM tracts are mainly composed of axons, and when these structures undergo apoptosis or lose their integrity, neurodegeneration may occur. Secondary neuronal degeneration can be classified as axonal degeneration and involves only the first neuron in a pathway (Wallerian degeneration of the corticospinal tract being its prototype) or be classified as transaxonal degeneration and involve more than a single neuron in a common pathway, usually a closed neuronal circuit, in specific tracts, such as the dentate-rubro-olivary tract, tracts of the limbic system, corticopontocerebellar tract, cranial nerve tracts, and nigrostriatal pathway. This study aimed to review the anatomy of the main CNS tracts susceptible to secondary neuronal degeneration and to illustrate, through different imaging modalities, the findings associated with this poorly explored and understood process involved in the pathophysiologic substrate of numerous neurologic diseases.Learning Objective: Recognize the anatomy of the main CNS tracts susceptible to secondary neuronal degeneration and identify its main imaging findings in different imaging modalities.


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