NI-18 A Quantitative Analysis of Intraoperative 3T-Diffusion Tensor Imaging parameters for Functional Prediction with Motor Eloquent Glioma Patients

Abstract OBJECTIVE: In motor eloquent glioma surgery, the value of intraoperative diffusion tensor (iDT) imaging was not established to preserve motor function. This study aimed to investigate a relationship between postoperative motor function and iDT imaging parameters, including fractional anisotropy (FA), mean diffusivity (MD), and shortest distance (SD) from resected tumor margin to the corticospinal tract (CST) of gliomas in motor eloquent areas. METHODS: This retrospective study enrolled 20 patients with newly diagnosed supratentorial glioma who underwent surgery and intraoperative magnetic resonance imaging at our hospital. Patients were divided into two groups (i.e., worsening and non-worsening groups) based on their manual muscle test scores before and three months after surgery. We obtained the mean FA and MD values bilaterally, along with identification of the CST and determined the ratios (the affected side / the contralateral side). The SD was measured between the CST and the resected margin of the tumor. We evaluated the quantitative analysis of these parameters related to motor functional outcomes. Moreover the correlation was measured between these parameters and the maximum reduction rate of cortical motor evoked potentials (MEPs) during surgery. RESULTS: In the worsening group (n = 5), the mean FA ratio was lower and the mean MD ratio was higher compared with the non-worsening group (n = 15; P < 0.001 and P < 0.01, respectively). Cut-off values were 0.87 for FA and 1.08 for MD. SD was 7.95 mm in the non-worsening group and 0.44 mm in the worsening group (P < 0.01). These iDT based parameters, the mean FA ratio and the SD, were well correlated with the maximum reduction rate in MEP (R = 0.72 and 0.80, respectively). CONCLUSIONS: The mean ratio of FA, MD, and SD using iDT imagings predict postoperative motor function and help in optimal surgical planning in patients with motor eloquent glioma.

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Demyelination and remyelination detected in an alternative cuprizone mouse model of multiple sclerosis with 7.0 T multiparameter magnetic resonance imaging

Scientific Reports ◽

10.1038/s41598-021-90597-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Shuang Ding ◽

Yu Guo ◽

Xiaoya Chen ◽

Silin Du ◽

Yongliang Han ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Multiple Sclerosis ◽

Magnetic Resonance ◽

Mouse Model ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Blue Staining ◽

Resonance Imaging ◽

The Mean ◽

Underlying Mechanisms

AbstractThe aim of this study was to investigate the mechanisms underlying demyelination and remyelination with 7.0 T multiparameter magnetic resonance imaging (MRI) in an alternative cuprizone (CPZ) mouse model of multiple sclerosis (MS). Sixty mice were divided into six groups (n = 10, each), and these groups were imaged with 7.0 T multiparameter MRI and treated with an alternative CPZ administration schedule. T2-weighted imaging (T2WI), susceptibility-weighted imaging (SWI), and diffusion tensor imaging (DTI) were used to compare the splenium of the corpus callosum (sCC) among the groups. Prussian blue and Luxol fast blue staining were performed to assess pathology. The correlations of the mean grayscale value (mGSV) of the pathology results and the MRI metrics were analyzed to evaluate the multiparameter MRI results. One-way ANOVA and post hoc comparison showed that the normalized T2WI (T2-nor), fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) values were significantly different among the six groups, while the mean phase (Φ) value of SWI was not significantly different among the groups. Correlation analysis showed that the correlation between the T2-nor and mGSV was higher than that among the other values. The correlations among the FA, RD, MD, and mGSV remained instructive. In conclusion, ultrahigh-field multiparameter MRI can reflect the pathological changes associated with and the underlying mechanisms of demyelination and remyelination in MS after the successful establishment of an acute CPZ-induced model.

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Accuracy of Diffusion Tensor Magnetic Resonance Imaging-Based Tractography for Surgery of Gliomas Near the Pyramidal Tract

Neurosurgery ◽

10.1227/neu.0b013e31823020e6 ◽

2011 ◽

Vol 70 (2) ◽

pp. 283-294 ◽

Cited By ~ 81

Author(s):

Shiro Ohue ◽

Shohei Kohno ◽

Akihiro Inoue ◽

Daisuke Yamashita ◽

Hironobu Harada ◽

...

Keyword(s):

Magnetic Resonance ◽

Motor Function ◽

Navigation System ◽

Diffusion Tensor ◽

Pyramidal Tract ◽

Motor Evoked Potentials ◽

Fiber Tracking ◽

Integrated Navigation ◽

Threshold Intensity ◽

Integrated Navigation System

Abstract BACKGROUND: Diffusion tensor (DT) imaging-based fiber tracking is a noninvasive magnetic resonance technique that can delineate the course of white matter fibers. OBJECTIVE: To evaluate the accuracy and usefulness of this DT imaging-based fiber tracking for surgery in patients with gliomas near the pyramidal tract (PT). METHODS: Subjects comprised 32 patients with gliomas near the PT. DT imaging-based fiber tracks of the PT were generated before and within 3 days after surgery in all patients. A tractography-integrated navigation system was used during the operation. Cortical and subcortical motor-evoked potentials (MEPs) were also monitored during resection to maximize the preservation of motor function. The threshold intensity for subcortical MEPs was examined by searching the stimulus points and changing the stimulus intensity. Minimum distance between the resection border and the illustrated PT was measured on postoperative tractography. RESULTS: In all subjects, DT imaging-based tractography of the PT was successfully performed, preoperatively demonstrating the relationship between tumors and the PT. With the use of the tractography-integrated navigation system and intraoperative MEPs, motor function was preserved postoperatively in all patients. A significant correlation was seen between threshold intensity for subcortical MEPs and the distance between the resection border and PT on postoperative DT imaging. CONCLUSION: DT imaging-based fiber tracking is a reliable and accurate method for mapping the course of subcortical PTs. Fiber tracking and intraoperative MEPs were useful for preserving motor function in patients with gliomas near the PT.

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Diffusion tensor imaging of the roots of the brachial plexus: a systematic review and meta-analysis of normative values

Clinical and Translational Imaging ◽

10.1007/s40336-020-00393-x ◽

2020 ◽

Vol 8 (6) ◽

pp. 419-431 ◽

Cited By ~ 1

Author(s):

Ryckie G. Wade ◽

Alexander Whittam ◽

Irvin Teh ◽

Gustav Andersson ◽

Fang-Cheng Yeh ◽

...

Keyword(s):

Brachial Plexus ◽

Diffusion Tensor ◽

Meta Analysis ◽

Mean Diffusivity ◽

Normative Values ◽

Spinal Root ◽

Experimental Conditions ◽

Tissue Microstructure ◽

The Mean ◽

Generalised Linear Modelling

Abstract Purpose Diffusion tensor magnetic resonance imaging (DTI) characterises tissue microstructure and provides proxy measures of myelination, axon diameter, fibre density and organisation. This may be valuable in the assessment of the roots of the brachial plexus in health and disease. Therefore, there is a need to define the normal DTI values. Methods The literature was systematically searched for studies of asymptomatic adults who underwent DTI of the brachial plexus. Participant characteristics, scanning protocols, and measurements of the fractional anisotropy (FA) and mean diffusivity (MD) of each spinal root were extracted by two independent review authors. Generalised linear modelling was used to estimate the effect of experimental conditions on the FA and MD. Meta-analysis of root-level estimates was performed using Cohen’s method with random effects. Results Nine articles, describing 316 adults (1:1 male:female) of mean age 35 years (SD 6) were included. Increments of ten diffusion sensitising gradient directions reduced the mean FA by 0.01 (95% CI 0.01, 0.03). Each year of life reduced the mean MD by 0.03 × 10–3 mm2/s (95% CI 0.01, 0.04). At 3-T, the pooled mean FA of the roots was 0.36 (95% CI 0.34, 0.38; I2 98%). The pooled mean MD of the roots was 1.51 × 10–3 mm2/s (95% CI 1.45, 1.56; I2 99%). Conclusions The FA and MD of the roots of the brachial plexus vary according to experimental conditions and participant factors. We provide summary estimates of the normative values in different conditions which may be valuable to researchers and clinicians alike.

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Characterization of abnormal diffusion properties of supratentorial brain tumors: a preliminary diffusion tensor imaging study

Journal of Neurosurgery Pediatrics ◽

10.3171/ped/2008/1/4/263 ◽

2008 ◽

Vol 1 (4) ◽

pp. 263-269 ◽

Cited By ~ 23

Author(s):

Weihong Yuan ◽

Scott K. Holland ◽

Blaise V. Jones ◽

Kerry Crone ◽

Francesco T. Mangano

Keyword(s):

Diffusion Tensor Imaging ◽

White Matter ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Imaging Study ◽

Low Grade ◽

High Grade ◽

The Mean ◽

Supratentorial Tumors ◽

Diffusion Properties

Object Diffusion tensor (DT) imaging was used in children with supratentorial tumors to evaluate the anisotropic diffusion properties between different tumor grades and between tumors and adjacent and contralateral white matter. Methods In this retrospective review, the authors review the cases of 16 children (age range 1–18 years) who presented to their institution with supratentorial tumors and were treated between 2004 and 2007. Eleven patients had low-grade and 5 had high-grade tumors. Fractional anisotropy (FA), mean diffusivity, and axial (λ∥) and radial (λ⊥) eigenvalues within selected regions were studied. Mitotic index, necrosis, and vascularity of the tumors were compared with DT imaging parameters. Results The mean diffusivity was significantly higher in low-grade than in high-grade tumors (p = 0.04); the 2 tumor grades also significantly differed for both λ∥ (p < 0.05) and λ⊥ (p < 0.05). Mean diffusivity values in low-grade tumors were significantly higher than in adjacent normal-appearing white matter (NAWM; p = 0.0004) and contralateral NAWM (p = 0.0001). In both low- and high-grade tumors, the FA was significantly lower than in NAWM (p < 0.0001 and p < 0.03, respectively) and contralateral NAWM (p < 0.0001 and p < 0.003, respectively). Tumor cellularity highly correlated with mean diffusivity and λ∥and λ⊥. Conclusions Diffusion tensor imaging is a useful tool in the evaluation of supratentorial tumors in children. The mean diffusivity appears to be a significant marker in differentiating tumors grades. Findings related to λ∥ and λ⊥ within tumor groups and between tumors and NAWM may be an indirect manifestation of the combined effects of axonal injury, demyelination, and tumor mass within the cranial compartment.

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A Diffusion Tensor Imaging Study on the Phonology-related Pathways in Cantonese-mandarin Bilinguals.

10.21203/rs.3.rs-1168282/v1 ◽

2021 ◽

Author(s):

Xiaoyu Xu ◽

Yuying Jin ◽

Ning Pan ◽

Muqing Cao ◽

Jin Jing ◽

...

Keyword(s):

White Matter ◽

Phonological Processing ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Imaging Study ◽

Brain White Matter ◽

The Mean ◽

The Right ◽

Long Term Experience

Abstract Cantonese and Mandarin are logographic languages, and the phonology is the main difference between the two languages. It is unclear whether long-term experience of Cantonese-Mandarin bilingualism will shape different brain white matter structures of pathways related to phonological processing. 30 Cantonese-Mandarin bilinguals and 30 Mandarin monolinguals completed diffusion-weighted imaging (DWI) scans and phonological processing tasks. The tractography and TBSS were used to investigate the structural differences in the bilateral superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF) and inferior fronto-occipital fasciculus (IFOF) between Cantonese-Mandarin bilinguals and Mandarin monolinguals. Post-hoc correlation analysis was conducted to investigate the relationship between the different structures with phonological processing skills. Compared to the Mandarin monolinguals, the Cantonese-Mandarin bilinguals had higher fractional anisotropy (FA) along the left ILF, higher mean diffusivity (MD) in the clusters along the temporoparietal segment of SLF (tSLF), as well as higher axial diffusivity (AD) in the right tSLF, IFOF, bilateral ILF. The mean AD of the different voxels in the right IFOF and the mean FA of the different voxels in the left ILF were positively correlated with the inverse efficiency score (IES) of the Cantonese auditory and Mandarin visual rhyming judgment tasks respectively within the bilingual group. Long-term experience of Cantonese-Mandarin bilinguals shape different brain white matter structures including right tSLF, IFOF, bilateral ILF. The bilinguals’ white matter showed higher diffusivity, especially in the axonal direction, than the monolinguals. These changes were related to bilinguals’ phonological processing.

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Maturation of Corpus Callosum Anterior Midbody Is Associated with Neonatal Motor Function in Eight Preterm-Born Infants

Neural Plasticity ◽

10.1155/2013/359532 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 17

Author(s):

Preethi Mathew ◽

Kerstin Pannek ◽

Pamela Snow ◽

M. Giulia D'Acunto ◽

Andrea Guzzetta ◽

...

Keyword(s):

Corpus Callosum ◽

Preterm Infants ◽

Motor Function ◽

Gestational Age ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Motor Impairments ◽

Very Preterm Infants ◽

Very Preterm ◽

Preterm Born

Background. The etiology of motor impairments in preterm infants is multifactorial and incompletely understood. Whether corpus callosum development is related to impaired motor function is unclear. Potential associations between motor-related measures and diffusion tensor imaging (DTI) of the corpus callosum in preterm infants were explored.Methods. Eight very preterm infants (gestational age of 28–32 weeks) underwent the Hammersmith neonatal neurological examination and DTI assessments at gestational age of 42 weeks. The total Hammersmith score and a motor-specific score (sum of Hammersmith motor subcategories) were calculated. Six corpus callosum regions of interest were defined on the mid-sagittal DTI slice—genu, rostral body, anterior midbody, posterior midbody, isthmus, and splenium. The fractional anisotropy (FA) and mean diffusivity (MD) of these regions were computed, and correlations between these and Hammersmith measures were sought.Results. Anterior midbody FA measures correlated positively with total Hammersmith (rho=0.929,P=0.001) and motor-specific scores (rho=0.857,P=0.007). Total Hammersmith scores also negatively correlated with anterior midbody MD measures (rho=−0.714,P=0.047).Discussion. These results suggest the integrity of corpus callosum axons, particularly anterior midbody axons, is important in mediating neurological functions. Greater callosal maturation was associated with greater motor function. Corpus callosum DTI may prove to be a valuable screening or prognostic marker.

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Injuries of the Cingulum and Fornix After Rupture of an Anterior Communicating Artery Aneurysm

Neurosurgery ◽

10.1227/neu.0b013e3182367124 ◽

2011 ◽

Vol 70 (4) ◽

pp. 819-823 ◽

Cited By ~ 16

Author(s):

Ji Heon Hong ◽

Byung Yeon Choi ◽

Chul Hoon Chang ◽

Seong Ho Kim ◽

Young Jin Jung ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

Memory Impairment ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Artery Aneurysm ◽

Aneurysm Rupture ◽

Diffusion Tensor Tractography ◽

Anterior Communicating Artery ◽

Imaging Parameters ◽

Age And Sex

Abstract BACKGROUND: After rupture of an anterior communicating artery (ACoA) aneurysm, the anterior cingulum and the fornix can be vulnerable to injury. However, very little is known about this topic. OBJECTIVE: To investigate injuries of the cingulum and fornix in patients with an ACoA aneurysm rupture with diffusion tensor tractography. METHODS: Eleven consecutive patients with an ACoA aneurysm rupture and 11 age- and sex-matched normal control subjects were recruited. Diffusion tensor imaging was scanned at an average of 54.1 days (range, 29–97 days) after onset of ACoA aneurysm rupture. RESULTS: We found that 6 (54.5%) and 7 (63.6%) of 11 patients revealed no trajectory of the anterior cingulum and the fornical body on diffusion tensor tractography, respectively. In terms of diffusion tensor imaging parameters, we found that the fractional anisotropy value and tract volume of the cingulum and fornix were decreased (P < .05) and that mean diffusivity values were increased (P < .05), except for those of the left fornix, which showed no difference (P > .05). CONCLUSION: We found injuries of the cingulum and fornix in patients with an ACoA aneurysm rupture. It is our belief that sustained memory impairment of patients with an ACoA aneurysm rupture might be related to injury of the cingulum and fornix. Therefore, we recommend evaluation of the cingulum and fornix with diffusion tensor tractography for patients with an ACoA aneurysm rupture.

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Diffusion tensor imaging of dorsal stream language areas in patients with post-stroke aphasia

Egyptian Journal of Radiology and Nuclear Medicine ◽

10.1186/s43055-021-00690-z ◽

2022 ◽

Vol 53 (1) ◽

Author(s):

Azza Elmongui ◽

Ahmed AbdelRazek ◽

Tamer Abou-Elsaad ◽

Tamer Belal ◽

Noha Ibrahim ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Dorsal Stream ◽

Functional Independence ◽

Post Stroke ◽

Non Invasive ◽

The Mean ◽

Sensitivity Specificity ◽

Language Areas

Abstract Background Aphasia complicating stroke occurs due to language deficits that decrease communication abilities and functional independence. Our study aims to assess fractional anisotropy (FA) and mean diffusivity (MD) parameters of diffusion tensor imaging (DTI) of the dorsal stream language areas in patients with post-stroke aphasia. It was conducted on 27 patients with post-stroke aphasia and 27 age- and sex-matched controls who underwent DTI of the brain. FA and MD values of Broca's area (BA), Wernick's area (WA), superior longitudinal fasciculus (SLF), and arcuate fasciculus (AF), and number of tract fibers (TF) of AF and SLF were calculated. Results were correlated with National Institutes of Health Stroke Scale (NIHSS), Arabic version of Comprehensive Aphasia Test (Arabic CAT), and Mansoura Arabic Screening Aphasia Test (MASAT). Results FA of AF and SLF in patients was significantly lower (P = 0.001) than controls. MD of AF and SLF in patients was significantly higher (P = 0.001) than controls. The mean volume TF of AF and SLF in patients was significantly (P = 0.001) lower than the mean volume in controls for AF and SLF. FA cutoff for AF was 0.34 and for SLF, it was 0.35 with sensitivity, specificity, and accuracy (85.2%, 62.1%, 73.2%) for AF, (74.1%, 69%, 71.4%) for SLF, respectively. MD cutoff value for AF was 0.87, and 0.84 for SLF with sensitivity, specificity, and accuracy (63%, 72.4%, 67.8%) for AF, (81.5%, 79.3%, 80.4%) for SLF, respectively. Cutoff TF of AF was 1728 and for SLF it was 601 with sensitivity, specificity, and accuracy (88.9%, 72.4%, 80.4%) for AF and (85.2%, 85.2%, 78.6%) for SLF, respectively. Conclusions DTI is a non-invasive promising method that can be used to assess language areas in patients with post-stroke aphasia.

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High-Resolution 3D in vivo Brain Diffusion Tensor Imaging at Ultrahigh Fields: Following Maturation on Juvenile and Adult Mice

Frontiers in Neuroscience ◽

10.3389/fnins.2020.590900 ◽

2020 ◽

Vol 14 ◽

Author(s):

Maxime Yon ◽

Qingjia Bao ◽

Odélia Jacqueline Chitrit ◽

Rafael Neto Henriques ◽

Noam Shemesh ◽

...

Keyword(s):

Diffusion Tensor Imaging ◽

High Resolution ◽

Olfactory Bulb ◽

Diffusion Tensor ◽

Post Partum ◽

Mean Diffusivity ◽

Planar Imaging ◽

The Mean ◽

Ultrahigh Fields

Diffusion tensor imaging (DTI) is a well-established technique for mapping brain microstructure and white matter tracts in vivo. High resolution DTI, however, is usually associated with low intrinsic sensitivity and therefore long acquisition times. By increasing sensitivity, high magnetic fields can alleviate these demands, yet high fields are also typically associated with significant susceptibility-induced image distortions. This study explores the potential arising from employing new pulse sequences and emerging hardware at ultrahigh fields, to overcome these limitations. To this end, a 15.2 T MRI instrument equipped with a cryocooled surface transceiver coil was employed, and DTI experiments were compared between SPatiotemporal ENcoding (SPEN), a technique that tolerates well susceptibility-induced image distortions, and double-sampled Spin-Echo Echo-Planar Imaging (SE-EPI) methods. Following optimization, SE-EPI afforded whole brain DTI maps at 135 μm isotropic resolution that possessed higher signal-to-noise ratios (SNRs) than SPEN counterparts. SPEN, however, was a better alternative to SE-EPI when focusing on challenging regions of the mouse brain –including the olfactory bulb and the cerebellum. In these instances, the higher robustness of fully refocused SPEN acquisitions coupled to its built-in zooming abilities, provided in vivo DTI maps with 75 μm nominal isotropic spatial resolution. These DTI maps, and in particular the mean diffusion direction (MDD) details, exhibited variations that matched very well the anatomical features known from histological brain Atlases. Using these capabilities, the development of the olfactory bulb (OB) in live mice was followed from week 1 post-partum, until adulthood. The diffusivity of this organ showed a systematic decrease in its overall isotropic value and increase in its fractional anisotropy with age; this maturation was observed for all regions used in the OB's segmentation but was most evident for the lobules' centers, in particular for the granular cell layer. The complexity of the OB neuronal connections also increased during maturation, as evidenced by the growth in directionalities arising in the mean diffusivity direction maps.

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Longitudinal comparison of pre- and postoperative diffusion tensor imaging parameters in young children with hydrocephalus

Journal of Neurosurgery Pediatrics ◽

10.3171/2009.11.peds09343 ◽

2010 ◽

Vol 5 (4) ◽

pp. 385-391 ◽

Cited By ~ 34

Author(s):

Ellen L. Air ◽

Weihong Yuan ◽

Scott K. Holland ◽

Blaise V. Jones ◽

Karin Bierbrauer ◽

...

Keyword(s):

White Matter ◽

Young Children ◽

Diffusion Tensor ◽

Mean Diffusivity ◽

Imaging Study ◽

The Other ◽

Healthy Children ◽

Shunt Insertion ◽

Vp Shunt ◽

Imaging Parameters

Object The goal in this study was to compare the integrity of white matter before and after ventriculoperitoneal (VP) shunt insertion by evaluating the anisotropic diffusion properties with the aid of diffusion tensor (DT) imaging in young children with hydrocephalus. Methods The authors retrospectively identified 10 children with hydrocephalus who underwent both pre- and postoperative DT imaging studies. The DT imaging parameters (fractional anisotropy [FA], mean diffusivity, axial diffusivity, and radial diffusivity) were computed and compared longitudinally in the splenium and genu of the corpus callosum (gCC) and in the anterior and posterior limbs of the internal capsule (PLIC). The patients' values on DT imaging at the pre- and postshunt stages were compared with the corresponding age-matched controls as well as with a large cohort of healthy children in the database. Results In the gCC, 7 of 10 children had abnormally low preoperative FA values, 6 of which normalized postoperatively. All 3 of the 10 children who had normal preoperative FA values had normal FA values postoperatively as well. In the PLIC, 7 of 10 children had abnormally high FA values, 6 of which normalized postoperatively, whereas the other one had abnormally low postoperative FA. Of the remaining 3 children, 2 had abnormally low preoperative FA values in the PLIC; this normalized in 1 patient after surgery. The other child had a normal preoperative FA value that became abnormally low postoperatively. When comparing the presurgery frequency of abnormally low, normal, and abnormally high FA values to those postsurgery, there was a statistically significant longitudinal difference in both gCC (p = 0.02) and PLIC (p = 0.002). Conclusions In this first longitudinal DT imaging study of young children with hydrocephalus, DT imaging anisotropy yielded abnormal results in several white matter regions of the brain, and trended toward normalization following VP shunt placement.

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