Human Connectome-Based Tractographic Atlas of the Brainstem Connections and Surgical Approaches

Neurosurgery ◽  
2016 ◽  
Vol 79 (3) ◽  
pp. 437-455 ◽  
Author(s):  
Antonio Meola ◽  
Fang-Cheng Yeh ◽  
Wendy Fellows-Mayle ◽  
Jared Weed ◽  
Juan C. Fernandez-Miranda
Keyword(s):  
Spatial Resolution ◽  
Diffusion Mri ◽  
Diffusion Tensor ◽  
Population Based ◽  
Medial Longitudinal Fasciculus ◽  
Surgical Approaches ◽  
Medial Lemniscus ◽  
Spinothalamic Tract ◽  
Rubrospinal Tract ◽  
Human Connectome Project

Abstract BACKGROUND The brainstem is one of the most challenging areas for the neurosurgeon because of the limited space between gray matter nuclei and white matter pathways. Diffusion tensor imaging-based tractography has been used to study the brainstem structure, but the angular and spatial resolution could be improved further with advanced diffusion magnetic resonance imaging (MRI). OBJECTIVE To construct a high-angular/spatial resolution, wide-population-based, comprehensive tractography atlas that presents an anatomical review of the surgical approaches to the brainstem. METHODS We applied advanced diffusion MRI fiber tractography to a population-based atlas constructed with data from a total of 488 subjects from the Human Connectome Project-488. Five formalin-fixed brains were studied for surgical landmarks. Luxol Fast Blue-stained histological sections were used to validate the results of tractography RESULTS We acquired the tractography of the major brainstem pathways and validated them with histological analysis. The pathways included the cerebellar peduncles, corticospinal tract, corticopontine tracts, medial lemniscus, lateral lemniscus, spinothalamic tract, rubrospinal tract, central tegmental tract, medial longitudinal fasciculus, and dorsal longitudinal fasciculus. Then, the reconstructed 3-dimensional brainstem structure was sectioned at the level of classic surgical approaches, namely supracollicular, infracollicular, lateral mesencephalic, perioculomotor, peritrigeminal, anterolateral (to the medulla), and retro-olivary approaches. CONCLUSION The advanced diffusion MRI fiber tracking is a powerful tool to explore the brainstem neuroanatomy and to achieve a better understanding of surgical approaches.

376 Human Connectome-Based Tractographic Atlas of the Brainstem Connections and Surgical Approaches

Neurosurgery ◽  
2017 ◽  
Vol 64 (CN_suppl_1) ◽  
pp. 289-289
Author(s):  
Antonio Meola ◽  
Fang-Cheng Yeh ◽  
Wendy Fellows-Mayle ◽  
Jared Weed ◽  
Juan Carlos Fernandez-Miranda
Keyword(s):  
Spatial Resolution ◽  
Diffusion Mri ◽  
Diffusion Tensor ◽  
Population Based ◽  
Medial Longitudinal Fasciculus ◽  
Surgical Approaches ◽  
Medial Lemniscus ◽  
Rubrospinal Tract ◽  
Human Connectome Project ◽  
Magnetic Resonance Imaging Mri

Abstract INTRODUCTION The brainstem is one of the most challenging areas for the neuro- surgeon because of the limited space between gray matter nuclei and white matter pathways. Diffusion tensor imaging based tractography has been used to study the brainstem structure, but the angular and spatial resolution could be improved further with advanced diffusion magnetic resonance imaging (MRI). Objective: To construct a high angular/spatial resolution, wide-population based, comprehensive tractography atlas that presents an anatomical review of the surgical approaches to the brainstem. METHODS We applied advanced diffusion MRI finer tractography to a population-based atlas constructed with data from a total of 488 subjects from the Human Connectome Project-488. Five formalin-fixed brains were studied for surgical landmarks. Luxol Fast Blue stained histological sections were used to validate the results of tractography. RESULTS >We acquired the tractography of the major brainstem pathways and vali- dated them with histological analysis. The pathways included the cerebellar peduncles, corticospinal tract, corticopontine tracts, medial lemniscus, lateral lemniscus, spino- thalamic tract, rubrospinal tract, central tegmental tract, medial longitudinal fasciculus, and dorsal longitudinal fasciculus. Then, the reconstructed 3-dimensional brainstem structure was sectioned at the level of classic surgical approaches, namely supra- collicular, infracollicular, lateral mesencephalic, perioculomotor, peritrigeminal, antero- lateral (to the medulla), and retro-olivary approaches. CONCLUSION The advanced diffusion MRI fiber tracking is a powerful tool to explore the brainstem neuroanatomy and to achieve a better understanding of surgical approaches.

The utility of preoperative diffusion tensor imaging in the surgical management of brainstem cavernous malformations

2015 ◽  
Vol 122 (3) ◽  
pp. 653-662 ◽  
Author(s):  
Bruno C. Flores ◽  
Anthony R. Whittemore ◽  
Duke S. Samson ◽  
Samuel L. Barnett
Keyword(s):  
Diffusion Tensor ◽  
Medial Longitudinal Fasciculus ◽  
Medial Lemniscus ◽  
Cavernous Malformations ◽  
Fiber Tracts ◽  
The Mean ◽  
Cerebellar Peduncle ◽  
Selection Of

OBJECT Resection of brainstem cavernous malformations (BSCMs) may reduce the risk of stepwise neurological deterioration secondary to hemorrhage, but the morbidity of surgery remains high. Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) are neuroimaging techniques that may assist in the complex surgical planning necessary for these lesions. The authors evaluate the utility of preoperative DTI and DTT in the surgical management of BSCMs and their correlation with functional outcome. METHODS A retrospective review was conducted to identify patients who underwent resection of a BSCM between 2007 and 2012. All patients had preoperative DTI/DTT studies and a minimum of 6 months of clinical and radiographic follow-up. Five major fiber tracts were evaluated preoperatively using the DTI/DTT protocol: 1) corticospinal tract, 2) medial lemniscus and medial longitudinal fasciculus, 3) inferior cerebellar peduncle, 4) middle cerebellar peduncle, and 5) superior cerebellar peduncle. Scores were applied according to the degree of distortion seen, and the sum of scores was used for analysis. Functional outcomes were measured at hospital admission, discharge, and last clinic visit using modified Rankin Scale (mRS) scores. RESULTS Eleven patients who underwent resection of a BSCM and preoperative DTI were identified. The mean age at presentation was 49 years, with a male-to-female ratio of 1.75:1. Cranial nerve deficit was the most common presenting symptom (81.8%), followed by cerebellar signs or gait/balance difficulties (54.5%) and hemibody anesthesia (27.2%). The majority of the lesions were located within the pons (54.5%). The mean diameter and estimated volume of lesions were 1.21 cm and 1.93 cm3, respectively. Using DTI and DTT, 9 patients (82%) were found to have involvement of 2 or more major fiber tracts; the corticospinal tract and medial lemniscus/medial longitudinal fasciculus were the most commonly affected. In 2 patients with BSCMs without pial presentation, DTI/DTT findings were important in the selection of the surgical approach. In 2 other patients, the results from preoperative DTI/DTT were important for selection of brainstem entry zones. All 11 patients underwent gross-total resection of their BSCMs. After a mean postoperative follow-up duration of 32.04 months, all 11 patients had excellent or good outcome (mRS Score 0–3) at the time of last outpatient clinic evaluation. DTI score did not correlate with long-term outcome. CONCLUSIONS Preoperative DTI and DTT should be considered in the resection of symptomatic BSCMs. These imaging studies may influence the selection of surgical approach or brainstem entry zones, especially in deep-seated lesions without pial or ependymal presentation. DTI/DTT findings may allow for more aggressive management of lesions previously considered surgically inaccessible. Preoperative DTI/DTT changes do not appear to correlate with functional postoperative outcome in long-term follow-up.

scholarly journals DACO: Distortion/artefact correction for diffusion MRI data in an integrated framework

2021 ◽  
Author(s):  
Yung-Chin Hsu ◽  
Wen-Yih Isaac Tseng
Keyword(s):  
Diffusion Mri ◽  
Diffusion Tensor ◽  
Mathematical Formulation ◽  
Magnetic Resonance Images ◽  
Model Parameters ◽  
Weighted Image ◽  
The Real ◽  
Integrated Framework ◽  
Human Connectome Project ◽  
Anatomical Images

In this paper we propose a registration-based algorithm to correct various distortions or artefacts (DACO) commonly observed in diffusion weighted (DW) magnetic resonance images (MRI). The registration in DACO is proceeded on the basis of a pseudo b_0 image, which is synthesized from the anatomical images such as T1-weighted image or T2-weighted image, and a pseudo diffusion MRI (dMRI) data, which is derived from the Gaussian model of diffusion tensor imaging (DTI) or the Hermite model of MAP-MRI. DACO corrects (1) the susceptibility-induced distortions, (2) the intensity inhomogeneity, and (3) the misalignment between the dMRI data and anatomical images by registering the real b_0 image to the pseudo b_0 image, and corrects (4) the eddy current (EC)-induced distortions and (5) the head motions by registering each of the DW images in the real dMRI data to the corresponding image in the pseudo dMRI data. As the above artefacts interact with each other, DACO models each type of artefact in an integrated framework and estimates these models in an interleaved and iterative manner. The mathematical formulation of the models and the comprehensive estimation procedures are detailed in this paper. The evaluation using the human connectome project data shows that DACO could estimate the model parameters accurately. Furthermore, the evaluation conducted on the real human data acquired from clinical MRI scanners reveals that the method could reduce the artefacts effectively. The DACO method leverages the anatomical image, which is routinely acquired in clinical practice, to correct the artefacts, minimizing the additional acquisitions needed to conduct the algorithm. Therefore, our method is beneficial to most dMRI data, particularly to those without acquiring the field map or blip-up and blip-down images.

scholarly journals Association between childhood trauma and risk for obesity: a putative neurocognitive developmental pathway

BMC Medicine ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Qiang Luo ◽  
◽  
Lingli Zhang ◽  
Chu-Chung Huang ◽  
Yan Zheng ◽  
...  
Keyword(s):  
Weight Gain ◽  
Childhood Abuse ◽  
Childhood Trauma ◽  
Diffusion Tensor ◽  
Behavioral Control ◽  
Structural Connectivity ◽  
Population Based ◽  
Imaging Data ◽  
Human Connectome Project ◽  
Morphometry Analysis

Abstract Background Childhood trauma increases the risk for adult obesity through multiple complex pathways, and the neural substrates are yet to be determined. Methods Participants from three population-based neuroimaging cohorts, including the IMAGEN cohort, the UK Biobank (UKB), and the Human Connectome Project (HCP), were recruited. Voxel-based morphometry analysis of both childhood trauma and body mass index (BMI) was performed in the longitudinal IMAGEN cohort; validation of the findings was performed in the UKB. White-matter connectivity analysis was conducted to study the structural connectivity between the identified brain region and subdivisions of the hypothalamus in the HCP. Results In IMAGEN, a smaller frontopolar cortex (FPC) was associated with both childhood abuse (CA) (β = − .568, 95%CI − .942 to − .194; p = .003) and higher BMI (β = − .086, 95%CI − .128 to − .043; p < .001) in male participants, and these findings were validated in UKB. Across seven data collection sites, a stronger negative CA-FPC association was correlated with a higher positive CA-BMI association (β = − 1.033, 95%CI − 1.762 to − .305; p = .015). Using 7-T diffusion tensor imaging data (n = 156), we found that FPC was the third most connected cortical area with the hypothalamus, especially the lateral hypothalamus. A smaller FPC at age 14 contributed to higher BMI at age 19 in those male participants with a history of CA, and the CA-FPC interaction enabled a model at age 14 to account for some future weight gain during a 5-year follow-up (variance explained 5.8%). Conclusions The findings highlight that a malfunctioning, top-down cognitive or behavioral control system, independent of genetic predisposition, putatively contributes to excessive weight gain in a particularly vulnerable population, and may inform treatment approaches.

scholarly journals TractoFlow: A robust, efficient and reproducible diffusion MRI pipeline leveraging Nextflow & Singularity

2019 ◽  
Author(s):  
Guillaume Theaud ◽  
Jean-Christophe Houde ◽  
Arnaud Boré ◽  
François Rheault ◽  
Felix Morency ◽  
...  
Keyword(s):  
Diffusion Mri ◽  
Diffusion Tensor ◽  
Brain Connectivity ◽  
Reversed Phase ◽  
Fiber Density ◽  
Processing Pipeline ◽  
Diffusion Weighted Images ◽  
Brain Extraction ◽  
Human Connectome Project ◽  
Over Time

AbstractA diffusion MRI (dMRI) tractography processing pipeline should be: i) reproducible in immediate test-test, ii) reproducible in time, iii) efficient and iv) easy to use. Two runs of the same processing pipeline with the same input data should give the same output today, tomorrow and in 2 years. However, processing dMRI data requires a large number of steps (20+ steps) that, at this time, may not be reproducible between runs or over time. If parameters such as the number of threads or the random number generator are not carefully set in the brain extraction, registration and fiber tracking steps, the end tractography results obtained can be far from reproducible and limit brain connectivity studies. Moreover, processing can take several hours to days of computation for a large database, even more so if the steps are running sequentially.To handle these issues, we present TractoFlow, a fully automated pipeline that processes datasets from the raw diffusion weighted images (DWI) to tractography. It also outputs classical diffusion tensor imaging measures (fractional anisotropy (FA) and diffu-sivities) and several HARDI measures (Number of Fiber Orientation (NuFO), Apparent Fiber Density (AFD)). The pipeline requires a DWI and T1-weighted image as NIfTI files and b-values/b-vectors in FSL format. An optional reversed phase encoded b=0 image can also be used. This pipeline is based on two technologies: Nextflow and Singularity, as well as recommended pre-processing and processing steps from the dMRI community. In this work, the TractoFlow pipeline is evaluated on three databases and shown to be efficient and reproducible from 98% to 100% depending on parameter choices. For example, 105 subjects from the Human Connectome Project (HCP) were fully ran in twenty-five (25) hours to produce, for each subject, a whole-brain tractogram with 4 million streamlines. The contribution of this paper is to introduce the importance of a robust pipeline in terms of runtime and reproducibility over time. In the era of open data and open science, efficiency and reproducibility is critical in neuroimaging projects. Our TractoFlow pipeline is publicly available for academic research and is an important step forward for better structural brain connectivity mapping.

Decreased Microstructural Integrity of the Central Somatosensory Tracts in Diabetic Peripheral Neuropathy

2021 ◽  
Author(s):  
Fang Fang ◽  
Qian Luo ◽  
Ren-Bin Ge ◽  
Meng-Yu Lai ◽  
Yu-Jia Gong ◽  
...  
Keyword(s):  
Peripheral Neuropathy ◽  
Diabetic Peripheral Neuropathy ◽  
Diffusion Tensor ◽  
Central Nervous System Involvement ◽  
Diabetic Patients ◽  
Medial Lemniscus ◽  
Type 2 Diabetic Patients ◽  
Spinothalamic Tract ◽  
Type 2 Diabetic

Abstract Context Although diabetic peripheral neuropathy (DPN) is predominantly considered a disorder of the peripheral nerves, some evidence for central nervous system involvement has recently emerged. However, whether or to what extent the microstructure of central somatosensory tracts may be injured remains unknown. Objective This work aimed to detect the microstructure of central somatosensory tracts in type 2 diabetic patients and to correlate it with the severity of DPN. Methods A case-control study at a tertiary referral hospital took place with 57 individuals with type 2 diabetes (25 with DPN, 32 without DPN) and 33 nondiabetic controls. The fractional anisotropy (FA) values of 2 major somatosensory tracts (the spinothalamic tract and its thalamocortical [spino-thalamo-cortical, STC] pathway, the medial lemniscus and its thalamocortical [medial lemnisco-thalamo-cortical, MLTC] pathway) were assessed based on diffusion tensor tractography. Regression models were further applied to detect the association of FA values with the severity of DPN in diabetic patients. Results The mean FA values of left STC and left MLTC pathways were significantly lower in patients with DPN than those without DPN and controls. Moreover, FA values of left STC and left MLTC pathways were significantly associated with the severity of DPN (expressed as Toronto Clinical Scoring System values) in patients after adjusting for multiple confounders. Conclusion Our findings demonstrated the axonal degeneration of central somatosensory tracts in type 2 diabetic patients with DPN. The parallel disease progression of the intracranial and extracranial somatosensory system merits further attention to the central nerves in diabetic patients with DPN.

scholarly journals Three-Dimensional Identification of the Medial Longitudinal Fasciculus in the Human Brain: A Diffusion Tensor Imaging Study

2020 ◽  
Vol 9 (5) ◽  
pp. 1340 ◽  
Author(s):  
Sang Seok Yeo ◽  
Sung Ho Jang ◽  
Jung Won Kwon ◽  
In Hee Cho
Keyword(s):  
Diffusion Tensor Imaging ◽  
Human Brain ◽  
Diffusion Tensor ◽  
Mean Diffusivity ◽  
Medial Longitudinal Fasciculus ◽  
Seed Region ◽  
Medial Lemniscus ◽  
Interstitial Nucleus Of Cajal ◽  
Posterior Side ◽  
Dti Tractography

Background: The medial longitudinal fasciculus (MLF) interacts with eye movement control circuits involved in the adjustment of horizontal, vertical, and torsional eye movements. In this study, we attempted to identify and investigate the anatomical characteristics of the MLF in human brain, using probabilistic diffusion tensor imaging (DTI) tractography. Methods: We recruited 31 normal healthy adults and used a 1.5-T scanner for DTI. To reconstruct MLFs, a seed region of interest (ROI) was placed on the interstitial nucleus of Cajal at the midbrain level. A target ROI was located on the MLF of the medulla in the reticular formation of the medulla. Mean values of fractional anisotropy, mean diffusivity, and tract volumes of MLFs were measured. Results: The component of the MLF originated from the midbrain MLF, descended through the posterior side of the medial lemniscus (ML) and terminated on the MLF of medulla on the posterior side of the ML in the medulla midline. DTI parameters of right and left MLFs were not significantly different. Conclusion: The tract of the MLF in healthy brain was identified by probabilistic DTI tractography. We believe this study will provide basic data and aid future comparative research on lesion or age-induced MLF changes.

scholarly journals An atlas of white matter anatomy, its variability, and reproducibility based on Constrained Spherical Deconvolution of diffusion MRI

2021 ◽  
Author(s):  
Ahmed M. Radwan ◽  
Stefan Sunaert ◽  
Kurt G. Schilling ◽  
Maxime Descoteaux ◽  
Bennett A. Landman ◽  
...  
Keyword(s):  
White Matter ◽  
Diffusion Mri ◽  
Diffusion Tensor ◽  
Single Subject ◽  
Constrained Spherical Deconvolution ◽  
Spherical Deconvolution ◽  
Pyramidal Tracts ◽  
Human Connectome Project ◽  
Subject Specific ◽  
Virtual Dissection

Virtual dissection of white matter (WM) using diffusion MRI tractography is confounded by its poor reproducibility. Despite the increased adoption of advanced reconstruction models, early region-of-interest driven protocols based on diffusion tensor imaging (DTI) remain the dominant reference for virtual dissection protocols. Here we bridge this gap by providing a comprehensive description of typical WM anatomy reconstructed using a reproducible automated subject-specific parcellation-based approach based on probabilistic constrained-spherical deconvolution (CSD) tractography. We complement this with a WM template in MNI space comprising 68 bundles, including all associated anatomical tract selection labels and associated automated workflows. Additionally, we demonstrate bundle inter- and intra-subject variability using 40 (20 test-retest) datasets from the human connectome project (HCP) and 5 sessions with varying b-values and number of b-shells from the single-subject Multiple Acquisitions for Standardization of Structural Imaging Validation and Evaluation (MASSIVE) dataset. The most reliably reconstructed bundles were the whole pyramidal tracts, primary corticospinal tracts, whole superior longitudinal fasciculi, frontal, parietal and occipital segments of the corpus callosum and middle cerebellar peduncles. More variability was found in less dense bundles, e.g., the first segment of the superior longitudinal fasciculus, fornix, dentato-rubro-thalamic tract (DRTT), and premotor pyramidal tract. Using the DRTT as an example, we show that this variability can be reduced by using a higher number of seeding attempts. Overall inter-session similarity was high for HCP test-retest data (median weighted-dice = 0.963, stdev = 0.201 and IQR = 0.099). Compared to the HCP-template bundles there was a high level of agreement for the HCP test-retest data (median weighted-dice = 0.747, stdev = 0.220 and IQR = 0.277) and for the MASSIVE data (median weighted-dice = 0.767, stdev = 0.255 and IQR = 0.338). In summary, this WM atlas provides an overview of the capabilities and limitations of automated subject-specific probabilistic CSD tractography for mapping white matter fasciculi in healthy adults. It will be most useful in applications requiring a highly reproducible parcellation-based dissection protocol, as well as being an educational resource for applied neuroimaging and clinical professionals.

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