Diffusion tensor imaging of pyramidal tract reorganization after pediatric stroke

George, Emilie; Heier, Linda; Kovanlıkaya, İlhami; Greenfield, Jeffrey P.

doi:10.1007/s00381-013-2351-x

Cited by 16 publications

(20 citation statements)

References 22 publications

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“…In the late stages of WD, cellular debris are removed, leading to increased water diffusion and subsequent slightly enhanced MD values (Maxwell et al, 2015). Our results were consistent with a previous study that revealed the FA value of the ipsilateral pyramidal tract in cerebral infarction patients on DTI was obviously decreased compared with the contralateral pyramidal tract on day 5 after onset, whereas there was no significant difference in MD between the two regions (George et al, 2014).…”

Section: Discussionsupporting

confidence: 92%

“…The following parameters were set: diffusion-weighted images (DWI) with a maximum proliferationsensitive factor b value of 1000 s/mm 2 , field of view (FOV), 230 x 230 mm; matrix size, 256 x 256; slice thickness, 5 mm; number of layers, 23; and layer spacing, 1 mm. The DTI scan was performed using a single-shot Echo-Planar Imaging sequence with the following parameters: FOV, 230 x 230 mm; matrix size, 256 x 256; slice thickness, 3 mm; number of layers, 42; layer spacing, 1 mm; and TR/TE, 9825/131 ms. Diffusion was applied along at least six noncollinear directions with an axial DWI maximum proliferation-sensitive factor b value of 700 s/mm 2 (George et al, 2014).…”

Section: Examination Methodsmentioning

confidence: 99%

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An assessment of the correlation between early postinfarction pyramidal tract Wallerian degeneration and nerve function recovery using diffusion tensor imaging

Guo¹,

Hao²,

Liu³

et al. 2017

Genet. Mol. Res.

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ABSTRACT. This study aimed to evaluate the clinical significance of diffusion tensor imaging (DTI) in the early diagnosis of pyramidal tract Wallerian degeneration (WD) and assessment of neurological recovery following cerebral infarction. This study included 23 patients with acute cerebral infarction and 10 healthy adult controls. All participants underwent both magnetic resonance imaging (MRI) and DTI scans. DTI images were analyzed using the Functional MRI of the Brain Software Library to determine the regions of interest (ROI) and obtain the mean diffusivity (MD) and fractional anisotropy (FA) value for each ROI. The correlation between FA or MD and postinfarction functional recovery of the nervous system was further analyzed to assess the feasibility of using a DTI scan in the evaluation of functional recovery of the nervous system in patients with cerebral infarction. DTI may be useful in detecting signals of early postinfarction pyramidal tract WD and is useful for the evaluation of postinfarction neurological recovery. Cerebral lesions were detected using MRI in all patients. It was found that in some patients, the FA value of the ipsilateral pyramidal tract on DTI was decreased as early as day 3 after the onset of infarction and in all patients by day 7. Subsequent correlation studies showed that the FA value of the ipsilateral pyramidal tract on day 13 was negatively correlated with the National Institutes of Health Stroke Scale score, but positively correlated with the Barthel Index, motricity index, and modified Rankin Scale scores.

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Section: Discussionsupporting

confidence: 92%

Section: Examination Methodsmentioning

confidence: 99%

An assessment of the correlation between early postinfarction pyramidal tract Wallerian degeneration and nerve function recovery using diffusion tensor imaging

Guo¹,

Hao²,

Liu³

et al. 2017

Genet. Mol. Res.

View full text Add to dashboard Cite

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“…1), it indicated no motor function of the tracked aberrant fiber tracts. These aberrant fiber tracts could be technical artifacts of DTI tractography or the fiber tracts could exist but had no motor function [18,19]. Conversely, in patient 3motor activation area and CST fiber tract reorganized at SMA and anterior part of paracentral lobule, which is conserved the foot motor area, is consistent with ECS results.…”

Section: Discussionsupporting

confidence: 86%

Plasticity of motor function and surgical outcomes in patients with cerebral arteriovenous malformation involving primary motor area: insight from fMRI and DTI

Wang

Lin

et al. 2016

Chin Neurosurg Jl

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Background: Patients who have a cerebral arteriovenous malformation (cAVMs) in the motor cortex can have displaced function. The finding and its relationship to recovery from surgery is not known. Methods: We present the five cases with cAVMs involving precentral knob and/or paracentral lobule and without preoperative motor deficits. We used motor activation areas derived from Functional functional MRI (fMRI) as a region of interesting (ROI) to launch the plasticity of cerebrospinal tracts (CST). All the results were incorporated into the neuronavigation platform for surgical treatment. Intraoperative electric cortical stimulation (ECS) was used to map motor areas. Modified Rankin Scale (mRS) of hands and feets were performed on postoperative day 2, 7 and at month 3, 6 during follow-up period. All the patients suffered from motor deficits regardless of cortical activation patterns. Results: Three patients showed functionally seeded CST in or around the AVM, and were validated by intraoperative electrical stimulation (ECS). Patient 4 had two aberrant functionally seeded fiber tracts away from the lesion, but were proved to be non-functional by postoperative motor deficits. Patient 3 with motor cortex and fiber tract within a diffuse AVMs nidus, complete paralysis of upper extremity after operation and has a persistent motor deficit during 6-month follow-up period. Conclusions: The plasticity of motor cortex on fMRI doesn't prevent post-operative motor deficits. Functionally mapped fiber tract within or abutting AVM nidus predicts transient and persistent motor deficit.

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“…1,34 In stroke studies, authors have proposed that preservation or recovery of the CST on DTI is mandatory for good recovery of impaired motor function. 15,20 However, the impact of LCD on surgical outcomes in patients with AVMs in eloquent areas has not been determined. 6 In recent years the feasibility of DTI in tracking fibers in AVM patients has been proven, although it has some methodological limitations.…”

Section: Discussionmentioning

confidence: 99%

Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area

Lin

Zhao

et al. 2016

JNS

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abbreviatioNs AUC = area under the ROC curve; AVM = arteriovenous malformation; BOLD = blood oxygen level-dependent; CST = corticospinal tract; DSA = digital subtraction angiography; DTI = diffusion tensor imaging; DW = diffusion weighted; EPI = echo-planar imaging; FA = fractional anisotropy; FAPA = feeding artery from perforating artery; fMRI = functional MRI; LAD = lesion-to-activation area distance; LCD = lesion-to-CST distance; MS = preoperative muscle strength; MS 1 = muscle strength 1 week postoperatively; MS 2 = muscle strength 6 months postoperatively; NPPB = normal perfusion pressure breakthrough; ROC = receiver operating characteristic; ROI = region of interest; SM = Spetzler-Martin; TOF = time-of-flight. obJective Case selection for the surgical treatment of arteriovenous malformations (AVMs) of the eloquent motor area remains challenging. The aim of this study was to determine the risk factors for worsened muscle strength after surgery in patients with this disorder. methods At their hospital the authors retrospectively studied 48 consecutive patients with AVMs involving motor cortex and/or the descending pathway. All patients had undergone preoperative functional MRI (fMRI) and diffusion tensor imaging (DTI), followed by resection. Both functional and angioarchitectural factors were analyzed with respect to the change in muscle strength. Functional factors included lesion-to-corticospinal tract distance (LCD) on DTI and lesion-toactivation area distance (LAD) and cortical reorganization on fMRI. Based on preoperative muscle strength, the changes in muscle strength at 1 week and 6 months after surgery were defined as short-term and long-term surgical outcomes, respectively. Statistical analysis was performed using the statistical package SPSS (version 20.0.0, IBM Corp.). results Twenty-one patients (43.8%) had worsened muscle strength 1 week after surgery. However, only 10 patients (20.8%) suffered from muscle strength worsening 6 months after surgery. The LCD was significantly correlated with short-term (p < 0.001) and long-term (p < 0.001) surgical outcomes. For long-term outcomes, patients in the 5 mm ≥ LCD > 0 mm (p = 0.009) and LCD > 5 mm (p < 0.001) categories were significantly associated with a lower risk of permanent motor worsening in comparison with patients in the LCD = 0 mm group. No significant difference was found between patients in the 5 mm ≥ LCD > 0 mm group and LCD > 5 mm group (p = 0.116). Nidus size was the other significant predictor of short-term (p = 0.021) and long-term (p = 0.016) outcomes. For long-term outcomes, the area under the ROC curve (AUC) was 0.728, and the cutoff point was 3.6 cm. Spetzler-Martin grade was not associated with short-term surgical outcomes (0.143), although it was correlated with long-term outcomes (0.038). coNclusioNs An AVM with a nidus in contact with tracked eloquent fibers (LCD = 0) and having a large size is more likely to be associated with worsened muscle strength after surgery in patients with eloquent motor area AVMs. Surgical treatment i...

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Diffusion tensor imaging of pyramidal tract reorganization after pediatric stroke

Abstract: These results point to plastic reorganization of the pyramidal tract post-stroke and the utility of DTI in recognizing these changes.

Cited by 16 publications

References 22 publications

An assessment of the correlation between early postinfarction pyramidal tract Wallerian degeneration and nerve function recovery using diffusion tensor imaging

An assessment of the correlation between early postinfarction pyramidal tract Wallerian degeneration and nerve function recovery using diffusion tensor imaging

Plasticity of motor function and surgical outcomes in patients with cerebral arteriovenous malformation involving primary motor area: insight from fMRI and DTI

Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area

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