scholarly journals Direct visualization and characterization of the human zona incerta and surrounding structures

2020 ◽  
Author(s):  
Jonathan C. Lau ◽  
Yiming Xiao ◽  
Roy A.M. Haast ◽  
Greydon Gilmore ◽  
Kamil Uludag ◽  
...  
Keyword(s):  
Zona Incerta ◽  
7 Tesla ◽  
Histological Evaluation ◽  
Medial Lemniscus ◽  
High Magnetic Field Strength ◽  
Deep Brain Region ◽  
Tissue Characteristics ◽  
The 19Th Century ◽  
Deep Brain

AbstractThe zona incerta (ZI) is a small gray matter region of the deep brain first identified in the 19th century, yet direct in vivo visualization and characterization has remained elusive. Noninvasive detection of the ZI and surrounding region could be critical to further our understanding of this widely connected but poorly understood deep brain region and could contribute to the development and optimization of neuromodulatory therapies. We demonstrate that high resolution (submillimetric) longitudinal (T1) relaxometry measurements at high magnetic field strength (7 Tesla) can be used to delineate the ZI from surrounding white matter structures, specifically the fasciculus cerebellothalamicus, fields of Forel (fasciculus lenticularis, fasciculus thalamicus, field H), and medial lemniscus. Using this approach, we successfully derived in vivo estimates of the size, shape, location, and tissue characteristics of substructures in the ZI region, confirming observations only previously possible through histological evaluation that this region is not just a space between structures but contains distinct morphological entities that should be considered separately. Our findings pave the way for increasingly detailed in vivo study and provide a structural foundation for precise functional and neuromodulatory investigation.

scholarly journals C.05 Direct visualization of the human zona incerta region using ultra-high field imaging: implications for stereotactic neurosurgery

2019 ◽  
Vol 46 (s1) ◽  
pp. S13
Author(s):  
JC Lau ◽  
TM Peters ◽  
Y Xiao ◽  
G Gilmore ◽  
KW MacDougall ◽  
...  
Keyword(s):  
High Field ◽  
T1 Mapping ◽  
Imaging Study ◽  
Zona Incerta ◽  
7 Tesla ◽  
Patient Specific ◽  
Ultra High Field ◽  
Fusion Methods ◽  
Deep Brain

Background: The zona incerta (ZI) is a small structure in the deep brain first identified by Auguste Forel for which robust in vivo visualization has remained elusive. The increased inherent signal from ultra-high field (7-Tesla or greater; 7T) magnetic resonance imaging (MRI) presents an opportunity to see structures not previously visible. In this study, we investigated the possibility of using quantitative T1 mapping at 7T to visualize the ZI region. Methods: We recruited healthy participants (N=32) and patients being considered for deep brain stimulation therapy as part of a prospective imaging study at 7T. Computational methods were used to process and fuse images to produce a high-resolution group average from which ZI anatomy could be delineated. Results: We pooled 7T data using image fusion methods and found that the contrast from quantitative T1 mapping was strikingly similar to classic histological staining, permitting facile identification of the ZI and nearby structures in reference to conventional stereotactic atlases. Conclusions: Using computational neuroimaging techniques, we demonstrate for the first time that the ZI is visible in vivo. Furthermore, we determined that this nuclear region can be decoupled from surrounding fibre pathways. This work paves the way for more accurate patient-specific optimization of deep brain targets for neuromodulation.

scholarly journals T1-weighted in vivo human whole brain MRI dataset with an ultrahigh isotropic resolution of 250 μm

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Falk Lüsebrink ◽  
Alessandro Sciarra ◽  
Hendrik Mattern ◽  
Renat Yakupov ◽  
Oliver Speck
Keyword(s):  
Brain Mri ◽  
Brain Magnetic Resonance Imaging ◽  
Brain Atlas ◽  
7 Tesla ◽  
Ultrahigh Resolution ◽  
Raw Data ◽  
Whole Brain ◽  
Isotropic Resolution ◽  
High Magnetic Field Strength

Abstract We present an ultrahigh resolution in vivo human brain magnetic resonance imaging (MRI) dataset. It consists of T1-weighted whole brain anatomical data acquired at 7 Tesla with a nominal isotropic resolution of 250 μm of a single young healthy Caucasian subject and was recorded using prospective motion correction. The raw data amounts to approximately 1.2 TB and was acquired in eight hours total scan time. The resolution of this dataset is far beyond any previously published in vivo structural whole brain dataset. Its potential use is to build an in vivo MR brain atlas. Methods for image reconstruction and image restoration can be improved as the raw data is made available. Pre-processing and segmentation procedures can possibly be enhanced for high magnetic field strength and ultrahigh resolution data. Furthermore, potential resolution induced changes in quantitative data analysis can be assessed, e.g., cortical thickness or volumetric measures, as high quality images with an isotropic resolution of 1 and 0.5 mm of the same subject are included in the repository as well.

Characteristics and distribution of somatosensory evoked potentials in the subthalamic region

2007 ◽  
Vol 107 (3) ◽  
pp. 548-554 ◽  
Author(s):  
Mayumi Kitagawa ◽  
Jun-Ichi Murata ◽  
Haruo Uesugi ◽  
Ritsuko Hanajima ◽  
Yoshikazu Ugawa ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Somatosensory Evoked Potentials ◽  
Anterior Commissure ◽  
Zona Incerta ◽  
Medial Lemniscus ◽  
Posterior Commissure ◽  
Topographical Distribution ◽  
The Mean ◽  
Deep Brain

Object The aim of the present study is to evaluate the topographical distribution of somatosensory evoked potentials (SSEPs) in the subthalamic area, including the zona incerta (ZI). Determination of this distribution may help in the correct placement of deep brain stimulation (DBS) leads. Methods Intraoperative SSEPs were recorded from contacts of DBS electrodes at 221 sites in 41 patients: three patients with essential tremor and 38 with Parkinson disease who underwent implantation of DBS electrodes for the relief of severe tremor or parkinsonism. Results Two distinct SSEPs were recorded in the subthalamic area. One was a monophasic positive wave with a mean latency of 15.8 ± 0.9 msec, which the authors designated subthalamic P16. Using both cephalic and noncephalic references, subthalamic P16 was only recorded in the ventral part of the ZI (mean 6.6 ± 1. 3 mm posterior to the midcommissure point, 4.8 ± 1.2 mm inferior to the anterior commissure–posterior commissure line, and 9.7 ± 0.6 mm lateral to the midline). When bipolar recordings were made, the traces showed a phase reversal at the caudal part of the ZI. The second potential is a positive–negative SSEP recorded throughout the entire subthalamic area. The mean latencies of the initial positive peak and the major negative peak were 13.6 ± 1.1 msec and 16.4 ± 1.1 msec, respectively. Several small notches were superimposed on the peaks, and their amplitudes were largest at the contact close to the medial lemniscus. Conclusions The results indicate that intraoperative SSEPs from DBS electrodes are helpful in refining stereotactic targets in the thalamus and subthalamic areas.

scholarly journals Longitudinal Automatic Segmentation of Hippocampal Subfields (LASHiS) using Multi-Contrast MRI

2019 ◽  
Author(s):  
Thomas Shaw ◽  
Ashley York ◽  
Maryam Ziaei ◽  
Markus Barth ◽  
Steffen Bollmann ◽  
...  
Keyword(s):  
Automatic Segmentation ◽  
7 Tesla ◽  
Single Subject ◽  
Similarity Coefficients ◽  
Cross Sectional ◽  
Mri Scans ◽  
Contrast Information ◽  
Tissue Characteristics ◽  
Time Point

AbstractThe volumetric and morphometric examination of hippocampus formation subfields in a longitudinal manner using in vivo MRI could lead to more sensitive biomarkers for neuropsychiatric disorders and diseases including Alzheimer’s disease, as the anatomical subregions are functionally specialised. Longitudinal processing allows for increased sensitivity due to reduced confounds of inter-subject variability and higher effect-sensitivity than cross-sectional designs. We examined the performance of a new longitudinal pipeline (Longitudinal Automatic Segmentation of Hippocampus Subfields [LASHiS]) against three freely available, published approaches. LASHiS automatically segments hippocampus formation subfields by propagating labels from cross-sectionally labelled time point scans using joint-label fusion to a non-linearly realigned ‘single subject template’, where image segmentation occurs free of bias to any individual time point. Our pipeline measures tissue characteristics available in in vivo high-resolution MRI scans, at both clinical (3 Tesla) and ultra-high field strength (7 Tesla) and differs from previous longitudinal segmentation pipelines in that it leverages multi-contrast information in the segmentation process. LASHiS produces robust and reliable automatic multi-contrast segmentations of hippocampus formation subfields, as measured by higher volume similarity coefficients and Dice coefficients for test-retest reliability and robust longitudinal Bayesian Linear Mixed Effects results at 7 T, while showing sound results at 3 T. All code for this project including the automatic pipeline is available at https://github.com/CAIsr/LASHiS

In Vivo Deep-Brain Structural and Hemodynamic Multiphoton Microscopy Enabled by Quantum Dots

Nano Letters ◽  
2019 ◽  
Vol 19 (8) ◽  
pp. 5260-5265 ◽  
Author(s):  
Hongji Liu ◽  
Xiangquan Deng ◽  
Shen Tong ◽  
Chen He ◽  
Hui Cheng ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Multiphoton Microscopy ◽  
Deep Brain

scholarly journals Antidiabetic and antiulcerative potential of Garcinia lanceifolia Roxb. bark

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Nilutpal Sharma Bora ◽  
Partha Sarathi Bairy ◽  
Abdus Salam ◽  
Bibhuti Bhusan Kakoti
Keyword(s):  
Body Weight ◽  
Serum Levels ◽  
Northeast India ◽  
Scientific Data ◽  
Antidiabetic Activity ◽  
Histological Evaluation ◽  
Albino Rats ◽  
Antiulcer Activity ◽  
Dose Dependent

Abstract Background Garcinia lanceifolia Roxb. has been used by many ethnic communities of Northeast India to mitigate various disorders like dyspepsia, ulcers, diabetes, etc. However, a robust scientific study on its antidiabetic and antiulcer potential is unavailable till date. The aim of this present study is to scientifically validate if the antidiabetic and antiulcer effects reported by the ethnic tribes of Assam has any scientific value or not. The effects were tested in adult Wistar albino rats using approved animal models for preclinical testing of pharmacological activities. Results The hydroalcoholic extract of the bark of Garcinia lanceifolia Roxb. was prepared and its LD50 was calculated. The LD50 was determined to be greater than 5000 mg/kg body weight. The extract at doses of 250 mg/kg body weight and 500 mg/kg body weight was found to exhibit a very potent dose-dependent antidiabetic activity. The results were backed by a battery of test including analysis of serum levels of blood glucose, lipid profiles, in vivo antioxidant enzymes, and histopathological studies. Evidence of dose-dependent antiulcer activity of the extract was backed by robust scientific data. It was found that HAEGL induced a significant dose-dependent increase in the ulcer index in both alcohol-induced and acetic acid-induced ulcer models, which was evident from the macroscopic observation of the inner lining of the gastric mucosa and the histological evaluation of the extracted stomach. Conclusion The results suggested that the bark of Garcinia lanceifolia (Roxb.) has significant antidiabetic and antiulcer potential. Further studies with respect to the development herbal dosage forms and its safety evaluation are required.

scholarly journals Alteration within the Hippocampal Volume in Patients with LHON Disease—7 Tesla MRI Study

2020 ◽  
Vol 10 (1) ◽  
pp. 14
Author(s):  
Cezary Grochowski ◽  
Kamil Jonak ◽  
Marcin Maciejewski ◽  
Andrzej Stępniewski ◽  
Mansur Rahnama-Hezavah
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Molecular Layer ◽  
Three Dimensional ◽  
Hippocampal Volume ◽  
7 Tesla ◽  
Diagnostic Process ◽  
Resonance Imaging ◽  
The Right

Purpose: The aim of this study was to assess the volumetry of the hippocampus in the Leber’s hereditary optic neuropathy (LHON) of blind patients. Methods: A total of 25 patients with LHON were randomly included into the study from the national health database. A total of 15 patients were selected according to the inclusion criteria. The submillimeter segmentation of the hippocampus was based on three-dimensional spoiled gradient recalled acquisition in steady state (3D-SPGR) BRAVO 7T magnetic resonance imaging (MRI) protocol. Results: Statistical analysis revealed that compared to healthy controls (HC), LHON subjects had multiple significant differences only in the right hippocampus, including a significantly higher volume of hippocampal tail (p = 0.009), subiculum body (p = 0.018), CA1 body (p = 0.002), hippocampal fissure (p = 0.046), molecular layer hippocampus (HP) body (p = 0.014), CA3 body (p = 0.006), Granule Cell (GC) and Molecular Layer (ML) of the Dentate Gyrus (DG)–GC ML DG body (p = 0.003), CA4 body (p = 0.001), whole hippocampal body (p = 0.018), and the whole hippocampus volume (p = 0.023). Discussion: The ultra-high-field magnetic resonance imaging allowed hippocampus quality visualization and analysis, serving as a powerful in vivo diagnostic tool in the diagnostic process and LHON disease course assessment. The study confirmed previous reports regarding volumetry of hippocampus in blind individuals.

scholarly journals A probabilistic atlas of the human ventral tegmental area (VTA) based on 7 Tesla MRI data

2021 ◽  
Vol 226 (4) ◽  
pp. 1155-1167 ◽  
Author(s):  
Anne C. Trutti ◽  
Laura Fontanesi ◽  
Martijn J. Mulder ◽  
Pierre-Louis Bazin ◽  
Bernhard Hommel ◽  
...  
Keyword(s):  
Ventral Tegmental Area ◽  
Region Of Interest ◽  
Reward Processing ◽  
7 Tesla ◽  
Subcortical Structures ◽  
7 Tesla Mri ◽  
Subcortical Nuclei ◽  
Ventral Tegmental ◽  
The Brain

AbstractFunctional magnetic resonance imaging (fMRI) BOLD signal is commonly localized by using neuroanatomical atlases, which can also serve for region of interest analyses. Yet, the available MRI atlases have serious limitations when it comes to imaging subcortical structures: only 7% of the 455 subcortical nuclei are captured by current atlases. This highlights the general difficulty in mapping smaller nuclei deep in the brain, which can be addressed using ultra-high field 7 Tesla (T) MRI. The ventral tegmental area (VTA) is a subcortical structure that plays a pivotal role in reward processing, learning and memory. Despite the significant interest in this nucleus in cognitive neuroscience, there are currently no available, anatomically precise VTA atlases derived from 7 T MRI data that cover the full region of the VTA. Here, we first provide a protocol for multimodal VTA imaging and delineation. We then provide a data description of a probabilistic VTA atlas based on in vivo 7 T MRI data.

Sign in / Sign up

Export Citation Format

Share Document