Functional outcome of surgery for glioma directly adjacent to pyramidal tract depicted by diffusion-tensor based fiber tracking

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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Intraoperative visualization of the pyramidal tract by diffusion-tensor-imaging-based fiber tracking

NeuroImage ◽

10.1016/j.neuroimage.2005.11.001 ◽

2006 ◽

Vol 30 (4) ◽

pp. 1219-1229 ◽

Cited By ~ 183

Author(s):

Christopher Nimsky ◽

Oliver Ganslandt ◽

Dorit Merhof ◽

A. Gregory Sorensen ◽

Rudolf Fahlbusch

Keyword(s):

Diffusion Tensor Imaging ◽

Diffusion Tensor ◽

Pyramidal Tract ◽

Fiber Tracking ◽

Intraoperative Visualization

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Accuracy of diffusion tensor magnetic resonance imaging tractography assessed using intraoperative subcortical stimulation mapping and magnetic source imaging

Journal of Neurosurgery ◽

10.3171/jns-07/09/0488 ◽

2007 ◽

Vol 107 (3) ◽

pp. 488-494 ◽

Cited By ~ 158

Author(s):

Jeffrey I. Berman ◽

Mitchel S. Berger ◽

Sungwon Chung ◽

Srikantan S. Nagarajan ◽

Roland G. Henry

Keyword(s):

White Matter ◽

Magnetic Resonance ◽

Diffusion Tensor ◽

Fiber Tracking ◽

Bipolar Electrode ◽

Source Imaging ◽

Magnetic Source Imaging ◽

Motor Pathway ◽

Magnetic Source ◽

Subcortical Stimulation

Object Resecting brain tumors involves the risk of damaging the descending motor pathway. Diffusion tensor (DT)–imaged fiber tracking is a noninvasive magnetic resonance (MR) technique that can delineate the subcortical course of the motor pathway. The goal of this study was to use intraoperative subcortical stimulation mapping of the motor tract and magnetic source imaging to validate the utility of DT-imaged fiber tracking as a tool for presurgical planning. Methods Diffusion tensor-imaged fiber tracks of the motor tract were generated preoperatively in nine patients with gliomas. A mask of the resultant fiber tracks was overlaid on high-resolution T1- and T2-weighted anatomical MR images and used for stereotactic surgical navigation. Magnetic source imaging was performed in seven of the patients to identify functional somatosensory cortices. During resection, subcortical stimulation mapping of the motor pathway was performed within the white matter using a bipolar electrode. Results A total of 16 subcortical motor stimulations were stereotactically identified in nine patients. The mean distance between the stimulation sites and the DT-imaged fiber tracks was 8.7 ±3.1 mm (±standard deviation). The measured distance between subcortical stimulation sites and DT-imaged fiber tracks combines tracking technique errors and all errors encountered with stereotactic navigation. Conclusions Fiber tracks delineated using DT imaging can be used to identify the motor tract in deep white matter and define a safety margin around the tract.

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Thalamic Connectivity in Patients with Essential Tremor Treated with MR Imaging–guided Focused Ultrasound: In Vivo Fiber Tracking by Using Diffusion-Tensor MR Imaging

Radiology ◽

10.1148/radiol.14132112 ◽

2014 ◽

Vol 272 (1) ◽

pp. 202-209 ◽

Cited By ~ 38

Author(s):

Max Wintermark ◽

Diane S. Huss ◽

Binit B. Shah ◽

Nicholas Tustison ◽

T. Jason Druzgal ◽

...

Keyword(s):

Mr Imaging ◽

Essential Tremor ◽

Focused Ultrasound ◽

Diffusion Tensor ◽

Fiber Tracking ◽

Diffusion Tensor Mr Imaging

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Enhanced Fiber Tractography Using Edema Correction: Application and Evaluation in High-Grade Gliomas

Neurosurgery ◽

10.1093/neuros/nyab129 ◽

2021 ◽

Author(s):

Fraser Henderson Jr ◽

Drew Parker ◽

Anupa A Vijayakumari ◽

Mark Elliott ◽

Timothy Lucas ◽

...

Keyword(s):

Magnetic Resonance ◽

Diffusion Tensor ◽

Free Water ◽

High Grade Glioma ◽

Fiber Tracking ◽

High Grade ◽

Peritumoral Edema ◽

Fiber Tractography ◽

Motor Pathways

Abstract BACKGROUND A limitation of diffusion tensor imaging (DTI)-based tractography is peritumoral edema that confounds traditional diffusion-based magnetic resonance metrics. OBJECTIVE To augment fiber-tracking through peritumoral regions by performing novel edema correction on clinically feasible DTI acquisitions and assess the accuracy of the fiber-tracks using intraoperative stimulation mapping (ISM), task-based functional magnetic resonance imaging (fMRI) activation maps, and postoperative follow-up as reference standards. METHODS Edema correction, using our bi-compartment free water modeling algorithm (FERNET), was performed on clinically acquired DTI data from a cohort of 10 patients presenting with suspected high-grade glioma and peritumoral edema in proximity to and/or infiltrating language or motor pathways. Deterministic fiber-tracking was then performed on the corrected and uncorrected DTI to identify tracts pertaining to the eloquent region involved (language or motor). Tracking results were compared visually and quantitatively using mean fiber count, voxel count, and mean fiber length. The tracts through the edematous region were verified based on overlay with the corresponding motor or language task-based fMRI activation maps and intraoperative ISM points, as well as at time points after surgery when peritumoral edema had subsided. RESULTS Volume and number of fibers increased with application of edema correction; concordantly, mean fractional anisotropy decreased. Overlay with functional activation maps and ISM-verified eloquence of the increased fibers. Comparison with postsurgical follow-up scans with lower edema further confirmed the accuracy of the tracts. CONCLUSION This method of edema correction can be applied to standard clinical DTI to improve visualization of motor and language tracts in patients with glioma-associated peritumoral edema.

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Quantitative diffusion tensor MRI-based fiber tracking of human skeletal muscle

Journal of Applied Physiology ◽

10.1152/japplphysiol.00290.2007 ◽

2007 ◽

Vol 103 (2) ◽

pp. 673-681 ◽

Cited By ~ 89

Author(s):

Drew A. Lansdown ◽

Zhaohua Ding ◽

Megan Wadington ◽

Jennifer L. Hornberger ◽

Bruce M. Damon

Keyword(s):

Muscle Fiber ◽

Diffusion Tensor ◽

Fiber Tracking ◽

Laboratory Frame ◽

Mean Value ◽

Pennation Angle ◽

Frame Of Reference ◽

Fiber Tracts ◽

Angle Measurements ◽

The Mean

Diffusion-tensor magnetic resonance imaging (DT-MRI) offers great potential for understanding structure-function relationships in human skeletal muscles. The purposes of this study were to demonstrate the feasibility of using in vivo human DT-MRI fiber tracking data for making pennation angle measurements and to test the hypothesis that heterogeneity in the orientation of the tibialis anterior (TA) muscle's aponeurosis would lead to heterogeneity in pennation angle. Eight healthy subjects (5 male) were studied. T1-weighted anatomical MRI and DT-MRI data were acquired of the TA muscle. Fibers were tracked from the TA's aponeurosis by following the principal eigenvector. The orientations of the aponeurosis and muscle fiber tracts in the laboratory frame of reference and the orientation of the fiber tracts with respect to the aponeurosis [i.e., the pennation angle (θ)] were determined. The muscle fiber orientations, when expressed relative to the laboratory frame of reference, did not change as functions of superior-to-inferior position. The sagittal and coronal orientations of the aponeurosis did not change in practically significant manners either, but the aponeurosis′ axial orientation changed by ∼40°. As a result, the mean value for θ decreased from 16.3 (SD 6.9) to 11.4° (SD 5.0) along the muscle's superior-to-inferior direction. The mean value of θ was greater in the deep than in the superficial compartment. We conclude that pennation angle measurements of human muscle made using DT-MRI muscle fiber tracking are feasible and reveal that in the foot-head direction, there is heterogeneity in the pennation properties of the human TA muscle.

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