scholarly journals Endoscopic Endonasal Transclival Approach to the Ventral Brainstem: Anatomic Study of the Safe Entry Zones Combining Fiber Dissection Technique with 7 Tesla Magnetic Resonance Guided Neuronavigation

2018 ◽  
Vol 16 (2) ◽  
pp. 239-249 ◽  
Author(s):  
Alessandro Weiss ◽  
Paolo Perrini ◽  
Matteo De Notaris ◽  
Guadalupe Soria ◽  
Alarcon Carlos ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
High Resolution ◽  
7 Tesla ◽  
Superior Cerebellar Artery ◽  
Endoscopic Endonasal ◽  
Close Relationship ◽  
Fresh Frozen ◽  
Fiber Dissection ◽  
Dissection Technique ◽  
Brainstem Anatomy

Abstract BACKGROUND Treatment of intrinsic lesions of the ventral brainstem is a surgical challenge that requires complex skull base antero- and posterolateral approaches. More recently, endoscopic endonasal transclival approach (EETA) has been reported in the treatment of selected ventral brainstem lesions. OBJECTIVE In this study we explored the endoscopic ventral brainstem anatomy with the aim to describe the degree of exposure of the ventral safe entry zones. In addition, we used a newly developed method combining traditional white matter dissection with high-resolution 7T magnetic resonance imaging (MRI) of the same specimen coregistered using a neuronavigation system. METHODS Eight fresh-frozen latex-injected cadaver heads underwent EETA. Additional 8 formalin-fixed brainstems were dissected using Klingler technique guided by ultra-high resolution MRI. RESULTS The EETA allows a wide exposure of different safe entry zones located on the ventral brainstem: the exposure of perioculomotor zone requires pituitary transposition and can be hindered by superior cerebellar artery. The peritrigeminal zone was barely visible and its exposure required an extradural anterior petrosectomy. The anterolateral sulcus of the medulla was visible in most of specimens, although its close relationship with the corticospinal tract makes it suboptimal as an entry point for intrinsic lesions. In all cases, the use of 7T-MRI allowed the identification of tiny fiber bundles, improving the quality of the dissection. CONCLUSION Exposure of the ventral brainstem with EETA requires mastering surgical maneuvers, including pituitary transposition and extradural petrosectomy. The correlation of fiber dissection with 7T-MRI neuronavigation significantly improves the understanding of the brainstem anatomy.

Anatomic Study of the Central Core of the Cerebrum Correlating 7-T Magnetic Resonance Imaging and Fiber Dissection With the Aid of a Neuronavigation System

2013 ◽  
Vol 10 (2) ◽  
pp. 294-304 ◽  
Author(s):  
Carlos Alarcon ◽  
Matteo de Notaris ◽  
Kenneth Palma ◽  
Guadalupe Soria ◽  
Alessandro Weiss ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
White Matter ◽  
Magnetic Resonance ◽  
Ex Vivo ◽  
Central Core ◽  
Resonance Imaging ◽  
Anatomic Study ◽  
Neuronavigation System ◽  
Fiber Dissection ◽  
Dissection Technique

Abstract BACKGROUND: Different strategies have been used to study the fiber tract anatomy of the human brain in vivo and ex vivo. Nevertheless, the ideal method to study white matter anatomy has yet to be determined because it should integrate information obtained from multiple sources. OBJECTIVE: We developed an anatomic method in cadaveric specimens to study the central core of the cerebrum combining traditional white matter dissection with high-resolution 7-T magnetic resonance imaging (MRI) of the same specimen coregistered using a neuronavigation system. METHODS: Ten cerebral hemispheres were prepared using the traditional Klingler technique. Before dissection, a structural ultrahigh magnetic field 7-T MRI study was performed on each hemisphere specifically prepared with surface fiducials for neuronavigation. The dissection was then performed from the medial hemispheric surface using the classic white fiber dissection technique. During each step of the dissection, the correlation between the anatomic findings and the 7-T MRI was evaluated with the neuronavigation system. RESULTS: The anatomic study was divided in 2 stages: diencephalic and limbic. The diencephalic stage included epithalamic, thalamic, hypothalamic, and subthalamic components. The limbic stage consisted of extending the dissection to complete the Papez circuit. The detailed information given by the combination of both methods allowed us to identify and validate the position of fibers that may be difficult to appreciate and dissect (ie, the medial forebrain bundle). CONCLUSION: The correlation of high-definition 7-T MRI and the white matter dissection technique with neuronavigation significantly improves the understanding of the structural connections in complex areas of the human cerebrum.

PD54-08 EX-VIVO EXPERIMENTAL 7 TESLA HIGH RESOLUTION MAGNETIC RESONANCE IMAGING - OF LOCALIZED PROSTATE CANCER

2020 ◽  
Vol 203 ◽  
pp. e1106-e1107
Author(s):  
Matthieu Durand* ◽  
Thomas Bessede ◽  
Patrick-Julien Treacy ◽  
Imad Bentellis ◽  
Idoia Corcuera-Solano ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Prostate Cancer ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Ex Vivo ◽  
Localized Prostate Cancer ◽  
7 Tesla ◽  
Resonance Imaging

scholarly journals Ex-vivo experimental 7 Tesla high resolution magnetic resonance imaging of localized prostate cancer

2020 ◽  
Vol 19 ◽  
pp. e585-e586
Author(s):  
M. Durand ◽  
T. Bessede ◽  
P-J. Treacy ◽  
I. Bentellis ◽  
I. Corcuera-Solano ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Prostate Cancer ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Ex Vivo ◽  
Localized Prostate Cancer ◽  
7 Tesla ◽  
Resonance Imaging

scholarly journals Lipid suppressed and tissue-fraction corrected metabolic distributions in human central brain structures using 2D 1H Magnetic Resonance Spectroscopic Imaging at 7 tesla

2020 ◽  
Author(s):  
Alex A. Bhogal ◽  
Tommy A.A. Broeders ◽  
Lisan Morsinkhof ◽  
Mirte Edens ◽  
Sahar Nassirpour ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
High Resolution ◽  
Spectroscopic Imaging ◽  
Magnetic Resonance Spectroscopic Imaging ◽  
Brain Diseases ◽  
7 Tesla ◽  
Partial Volume ◽  
Scan Time ◽  
Central Brain

ABSTRACTMagnetic resonance spectroscopic imaging (MRSI) has the potential to add a layer of understanding of the neurobiological mechanisms underlying brain diseases, disease progression, and treatment efficacy. Limitations related to metabolite fitting of low SNR data, signal variations due to partial volume effects, acquisition and extra-cranial lipid artefacts, along with clinically relevant aspects such as scan-time constraints, are among the factors that hinder the widespread implementation of in vivo MRSI. The aim of this work was to address these factors and to develop an acquisition, reconstruction and post-processing pipeline to derive lipid suppressed metabolite values based on Free Induction Decay (FID-MRSI) measurements made using a 7 tesla MR scanner. Anatomical images were used to perform high-resolution (1mm3) partial-volume correction to account for grey matter, white matter and cerebral-spinal fluid signal contributions. Implementation of automatic quality control thresholds and normalization of metabolic maps from 23 subjects to the MNI standard atlas facilitated the creation of high-resolution average metabolite maps of several clinically relevant metabolites in central brain regions, while accounting for macromolecular distributions. Reported metabolite values include glutamate, choline, (phospo)creatine, myo-inositol, glutathione, N-acetyl aspartyl glutamate(and glutamine) and N-acetyl aspartate. MNI-registered average metabolite maps facilitate group-based analysis; thus offering the possibility to mitigate uncertainty in variable MRSI.

scholarly journals A High-Resolution Interactive Atlas of the Human Brainstem Using Magnetic Resonance Histology

Neurosurgery ◽  
2020 ◽  
Vol 67 (Supplement_1) ◽  
Author(s):  
Syed M Adil ◽  
Evan Calabrese ◽  
Lefko T Charalambous ◽  
James Cook ◽  
Shervin Rahimpour ◽  
...  
Keyword(s):  
White Matter ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Spatial Resolution ◽  
7 Tesla ◽  
Acquisition Time ◽  
Superior Cerebellar Peduncle ◽  
Corticospinal Tracts ◽  
Custom Made ◽  
And Diffusion

Abstract INTRODUCTION Traditional atlases of the human brainstem are limited by the inflexible, sparsely-sampled, two-dimensional nature of histology or the low spatial resolution of magnetic resonance imaging (MRI). Magnetic resonance histology (MRH) uses postmortem high-resolution MRI to circumvent the challenges associated with both modalities. METHODS A human brainstem specimen extending from the rostral diencephalon through the caudal medulla was removed from a 65-year-old male within 24 hours of death. The specimen was formalin-fixed for two weeks, then rehydrated and placed in a custom-made MRI compatible tube and immersed in buffered liquid fluorocarbon. MRI was performed in a 7-Tesla machine with 120 unique diffusion directions. Acquisition time for anatomic and diffusion images were 14 hours and 208 hours, respectively. Segmentation was performed manually. Deterministic fiber tractography was done using strategically chosen regions of interest and avoidance, with manual editing using expert knowledge of human neuroanatomy. RESULTS Anatomic and diffusion images were rendered with isotropic resolutions of 50 μm and 200 μm, respectively. Spatial resolution was high enough to visualize individual fasciculi of the descending corticospinal tracts intercalated between the transverse pontocerebellar fibers. Ninety different structures were segmented and 11 different fiber bundles were rendered with tractography. Angular resolution was high enough to visualize crossing fibers, such as those of the superior cerebellar peduncle. Both gray and white matter can be visualized in 3D simultaneously, such as the subthalamic nuclei and corticospinal tracts, as may be used in deep brain stimulation. CONCLUSION We used MRH to enable unprecedented resolution in digital imaging of the human brainstem and adjacent diencephalic structures, and we then performed comprehensive segmentation and tractography to render an interactive, three-dimensional atlas of both gray and white matter. This atlas has immediate applications in neuroanatomical study and education, with the potential for future neurosurgical applications in enhancing neurosurgical planning through “safe” zones of entry into the human brainstem. We are currently building the computer infrastructure to make this atlas publicly-available.

scholarly journals Investigating disparity organisation in the human early visual cortex with high resolution magnetic resonance imaging (7 Tesla)

2012 ◽  
Vol 12 (9) ◽  
pp. 41-41
Author(s):  
G. S. L. Coullon ◽  
R. M. Sanchez-Panchuelo ◽  
S. Francis ◽  
D. Schluppeck ◽  
A. J. Parker ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Visual Cortex ◽  
Magnetic Resonance ◽  
High Resolution ◽  
7 Tesla ◽  
Resonance Imaging ◽  
Early Visual Cortex

Abstract W P45: High Resolution Images of Perforating Arteries With 7T MRA in Acute Subcortical Infarction

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Hideki Ohba ◽  
Taisuke Harada ◽  
Makoto Sasaki ◽  
Kazumasa Ohura ◽  
Tatsunori Natori ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
High Resolution ◽  
Infarct Volume ◽  
7 Tesla ◽  
Ischemic Lesion ◽  
Clinical Prognosis ◽  
Tof Mra ◽  
Perforating Artery ◽  
Subcortical Infarction ◽  
Perforating Arteries

Introduction: Patients with acute subcortical infarction show various clinical courses according to the pathology of perforating artery so that the noninvasive and precise neuroradiological evaluation of these arteries is very important for prevention of progression and recurrence of the disease. 7 Tesla (7T) - MRI (Magnetic Resonance Imaging) makes it possible to visualize perforating arteries in a way that would not otherwise be possible using conventional MRI. We attempted to assess perforating arteries and infarct lesions in the lenticulostriate artery (LSA) area using 7T- High resolution MRA (Magnetic Resonance Angiography), and to evaluate the association between image findings and clinical courses of treatment. Method: We included 13 patients (M:F = 7:6, mean age: 65 years old) with acute noncardioembolic stroke in LSA area detected by 1.5-T MRI. 7T MRI was acquired among these patients within 2 weeks after onset to visualize responsible LSA and to measure the volume of infarction by 7T-MRI- 3D-TOF MRA, 3D-FLAIR. We also evaluated the association between these results and the severity of stroke by National Institute of Health Stroke Scale (NIHSS). Results: Perforating arteries in the basal ganglia area were clearly visualized in all patients using 7T MRA. According to the location of occlusion and ischemic lesion, patients were categorized into 3 groups (A, B, and C): Group A - patients with proximal branch occlusion of LSA (2 cases), Group B - patients with occlusion of LSA adjacent to the ischemic lesion (7 cases), Group C - no occlusions (4 cases) in LSA associated with infarction. Significant association between overall infarct volume and NIHSS(r=0.636, p=0.020)was observed, whereas infarct volume of each group was not associated with NIHSS. Clinical outcome were not associated with volume of infarction in all cases(p=0.12). However, there were no patients whose symptoms progressed in Group C. Conclusion: 7 T-MRA can provide a clear visualization of perforating arteries and occluded lesions. It can be a useful and noninvasive diagnostic tool to study clinical prognosis after treatment in acute subcortical infarction.

scholarly journals Hippocampal vascularization patterns: A high-resolution 7 Tesla time-of-flight magnetic resonance angiography study

2019 ◽  
Vol 21 ◽  
pp. 101609 ◽  
Author(s):  
Marco Spallazzi ◽  
Laura Dobisch ◽  
Andreas Becke ◽  
David Berron ◽  
Daniel Stucht ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
High Resolution ◽  
Magnetic Resonance Angiography ◽  
Time Of Flight ◽  
7 Tesla

Functional information from magnetic resonance imaging

1995 ◽  
Vol 53 ◽  
pp. 84-85
Author(s):  
Alan P. Koretsky ◽  
Afonso Costa e Silva ◽  
Yi-Jen Lin
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Cancer Biology ◽  
Imaging Modality ◽  
Magnetic Resonance Images ◽  
Great Success ◽  
Functional Information ◽  
Resonance Imaging ◽  
High Resolution Mri

Magnetic resonance imaging (MRI) has become established as an important imaging modality for the clinical management of disease. This is primarily due to the great tissue contrast inherent in magnetic resonance images of normal and diseased organs. Due to the wide availability of high field magnets and the ability to generate large and rapidly switched magnetic field gradients there is growing interest in applying high resolution MRI to obtain microscopic information. This symposium on MRI microscopy highlights new developments that are leading to increased resolution. The application of high resolution MRI to significant problems in developmental biology and cancer biology will illustrate the potential of these techniques.In combination with a growing interest in obtaining high resolution MRI there is also a growing interest in obtaining functional information from MRI. The great success of MRI in clinical applications is due to the inherent contrast obtained from different tissues leading to anatomical information.

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