Midbrain: a Clinico-Pathological Study
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Magnetic Resonance Imaging of Multiple Sclerosis: a Study of Pulse-Technique Efficacy
691 Magnetic Resonance Imaging of Multiple Sclerosis: A Study of Pulse-Technique Efficacy Val M. Runge1 Forty-two patients with the clinical diagnosis of multiple sclerosis were examined by Ann C. Price1 proton magnetic resonance imaging (MRI) at 0.5 T. An extensive protocol was used to Howard S. Kirshner2 facilitate a comparison of the efficacy of different pulse techniques. Results were also Joseph H. Allen 1 compared in 39 cases with high-resolution x-ray computed tomography (CT). MRI revealed characteristic abnormalities in each case, whereas CT was positive in only 15 C. Leon Partain 1 of 33 patients. Milder grades 1 and 2 disease were usually undetected by CT, and in all A. Everette James, Jr.1 cases, the abnormalities noted on MRI were much more extensive than on CT. Cerebral abnormalities were best shown with the T2-weighted spin-echo sequence (TE/TR = 120/1000); brainstem lesions were best defined on the inversion-recovery sequence (TE/TI/TR =30/400/1250). Increasing TE to 120 msec and TR to 2000 msec heightened the contrast between normal and abnormal white matter. However, the signal intensity of cerebrospinal fluid with this pulse technique obscured some abnormalities. The diagnosis of multiple sclerosis continues to be a clinical challenge [1,2). The lack of an objective means of assessment further complicates the evaluation of treatment regimens. Evoked potentials, cerebrospinal fluid (CSF) analysis , and computed tomography (CT) are currently used for diagnosis, but all lack sensitivity and/or specificity. Furthermore, postmortem examinations demonstrate many more lesions than those suggested by clinical means [3). -
Brainstem: Structure & Its Mode of Action
Journal of Neurology & Neurophysiology 2021, Vol.12, Issue 3, 521 Opinion Brainstem: Structure & Its Mode of action Karthikeyan Rupani Research Fellow, Tata Medical Centre, India. Corresponding Author* The brainstem is exceptionally little, making up around as it were 2.6 percent of the brain's add up to weight. It has the basic parts of directing cardiac, and Rupani K, respiratory work, making a difference to control heart rate and breathing rate. Research Fellow, Tata Medical Centre, India; It moreover gives the most engine and tactile nerve supply to the confront and E-mail: [email protected] neck by means of the cranial nerves. Ten sets of cranial nerves come from the brainstem. Other parts incorporate the direction of the central apprehensive Copyright: 2021 Rupani K. This is an open-access article distributed under the framework and the body's sleep cycle. It is additionally of prime significance terms of the Creative Commons Attribution License, which permits unrestricted within the movement of engine and tangible pathways from the rest of the use, distribution, and reproduction in any medium, provided the original author brain to the body, and from the body back to the brain. These pathways and source are credited. incorporate the corticospinal tract (engine work), the dorsal column-medial lemniscus pathway and the spinothalamic tract [3]. The primary part of the brainstem we'll consider is the midbrain. The midbrain Received 01 March 2021; Accepted 15 March 2021; Published 22 March 2021 (too known as the mesencephalon) is the foremost prevalent of the three districts of the brainstem. It acts as a conduit between the forebrain over and the pons and cerebellum underneath. -
The Brain Stem Medulla Oblongata
Chapter 14 The Brain Stem Medulla Oblongata Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Central sulcus Parietal lobe • embryonic myelencephalon becomes Cingulate gyrus leaves medulla oblongata Corpus callosum Parieto–occipital sulcus Frontal lobe Occipital lobe • begins at foramen magnum of the skull Thalamus Habenula Anterior Epithalamus commissure Pineal gland • extends for about 3 cm rostrally and ends Hypothalamus Posterior commissure at a groove between the medulla and Optic chiasm Mammillary body pons Cerebral aqueduct Pituitary gland Fourth ventricle Temporal lobe • slightly wider than spinal cord Cerebellum Midbrain • pyramids – pair of external ridges on Pons Medulla anterior surface oblongata – resembles side-by-side baseball bats (a) • olive – a prominent bulge lateral to each pyramid • posteriorly, gracile and cuneate fasciculi of the spinal cord continue as two pair of ridges on the medulla • all nerve fibers connecting the brain to the spinal cord pass through the medulla • four pairs of cranial nerves begin or end in medulla - IX, X, XI, XII Medulla Oblongata Associated Functions • cardiac center – adjusts rate and force of heart • vasomotor center – adjusts blood vessel diameter • respiratory centers – control rate and depth of breathing • reflex centers – for coughing, sneezing, gagging, swallowing, vomiting, salivation, sweating, movements of tongue and head Medulla Oblongata Nucleus of hypoglossal nerve Fourth ventricle Gracile nucleus Nucleus of Cuneate nucleus vagus -
Integrative Actions of the Reticular Formation the Reticular Activating System, Autonomic Mechanisms and Visceral Control
University of Nebraska Medical Center DigitalCommons@UNMC MD Theses Special Collections 5-1-1964 Integrative actions of the reticular formation The reticular activating system, autonomic mechanisms and visceral control George A. Young University of Nebraska Medical Center This manuscript is historical in nature and may not reflect current medical research and practice. Search PubMed for current research. Follow this and additional works at: https://digitalcommons.unmc.edu/mdtheses Part of the Medical Education Commons Recommended Citation Young, George A., "Integrative actions of the reticular formation The reticular activating system, autonomic mechanisms and visceral control" (1964). MD Theses. 69. https://digitalcommons.unmc.edu/mdtheses/69 This Thesis is brought to you for free and open access by the Special Collections at DigitalCommons@UNMC. It has been accepted for inclusion in MD Theses by an authorized administrator of DigitalCommons@UNMC. For more information, please contact [email protected]. THE INTEGRATIVE ACTIONS OF THE RETICULAR FORlVIATION The Reticular Activating System, Autonomic Mechanisms and Visceral Control George A. Young 111 Submitted in Partial Fulfillment for the Degree of Doctor of Medicine College of Medicine, University of Nebraska February 3, 1964 Omaha, Nebraska TABLE OF CONTENTS Page I. Introduction. ~4'~ •••••••••••• *"' ••• " ••• "' ••• 1I •• 1 II. The Reticula.r Activa.ting System (a) Historical Review •••.....•..•.•. · ••••• 5 (1) The Original Paper~ ..•.••...••.••••. 8 (2) Proof For a R.A.S •.•...•.....•••.• ll (b) ,The Developing Concept of the R.A.S ••• 14 (1) R.A.S. Afferents •..•.•......••..• 14 (2) The Thalamic R.F •••.••.......••.••. 16 (3) Local Cortical Arousal •••••••.•.••• 18 (4) The Hypothalamus end the R.A.S ••••• 21 (5) A Reticular Desynchronizing System. -
MRI Atlas of the Human Deep Brain Jean-Jacques Lemaire
MRI Atlas of the Human Deep Brain Jean-Jacques Lemaire To cite this version: Jean-Jacques Lemaire. MRI Atlas of the Human Deep Brain. 2019. hal-02116633 HAL Id: hal-02116633 https://hal.uca.fr/hal-02116633 Preprint submitted on 1 May 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives| 4.0 International License MRI ATLAS of the HUMAN DEEP BRAIN Jean-Jacques Lemaire, MD, PhD, neurosurgeon, University Hospital of Clermont-Ferrand, Université Clermont Auvergne, CNRS, SIGMA, France This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-nd/4.0/ or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA. Terminologia Foundational Model Terminologia MRI Deep Brain Atlas NeuroNames (ID) neuroanatomica usages, classical and french terminologies of Anatomy (ID) Anatomica 1998 (ID) 2017 http://fipat.library.dal.ca In -
Overview of the Reticular Formation (RF)
TeachSheet Reticular Formation & Diffuse modulatory system Overview of the Reticular Formation (RF) The term reticular formation refers to the neuronal network within the brainstem, although it continues rostrally into the thalamus and hypothalamus and caudally into the propriospinal network of the spinal cord. A “coordinating system” (like the Limbic system) with “connections” to sensory, somatic motor and visceral motor systems Organization can be subdivided into two neuronal cell “columns” (medial to lateral) as well as on the basis of their neurotransmitter release Neuronal columns (many nuclei and names, but these are some of the major ones): o “Medial tegmental field” (large-celled nuclei) . Origin of the reticulospinal pathway . Role in coordinating posture, eye and head movements. o “Lateral tegmental field” (smaller and fewer cells, shorter local projections) . Extends from the medulla to the pons . Coordinate autonomic and limbic functions (e.g. micturition, swallowing, mastication and vocalization) The functions of the reticular formation include their ability to coordinate motor and sensory brainstem nuclei: o Pattern generator . Eye movements; horizontal (PPRF) and vertical (riMLF) . Rhythmical chewing movements (pons) . Posture and locomotion (midbrain and pons) . Swallowing, vomiting, coughing and sneezing (medulla) . Micturition (pons) o Respiratory control (medulla); expiratory, inspiratory, apneustic and pneumotaxic o Cardiovascular control (medulla); vasomotor pressor/depressor, cardioacceleratory and inhibitory. Afferents arise from baroreceptors (carotid sinus and aortic arch), chemoreceptors (carotid sinus, lateral reticular formation chemosensitive area in the medulla) and stretch receptors (lung and respiratory muscles) . Efferents arise from reticular formation neurons within the pons and medulla o Sensory modulation or “gate” control . The term “gating” refers to “modulation” of synaptic transmission from one set of neurons to the next. -
Magnetic Resonance Imaging of Mediodorsal, Pulvinar, and Centromedian Nuclei of the Thalamus in Patients with Schizophrenia
ORIGINAL ARTICLE Magnetic Resonance Imaging of Mediodorsal, Pulvinar, and Centromedian Nuclei of the Thalamus in Patients With Schizophrenia Eileen M. Kemether, MD; Monte S. Buchsbaum, MD; William Byne, MD, PhD; Erin A. Hazlett, PhD; Mehmet Haznedar, MD; Adam M. Brickman, MPhil; Jimcy Platholi, MA; Rachel Bloom Background: Postmortem and magnetic resonance im- reduced in all 3 nuclei; differences in relative reduction aging (MRI) data have suggested volume reductions in did not differ among the nuclei. The remainder of the the mediodorsal (MDN) and pulvinar nuclei (PUL) of the thalamic volume (whole thalamus minus the volume of thalamus. The centromedian nucleus (CMN), impor- the 3 delineated nuclei) was not different between schizo- tant in attention and arousal, has not been previously stud- phrenic patients and controls, indicating that the vol- ied with MRI. ume reduction was specific to these nuclei. Volume rela- tive to brain size was reduced in all 3 nuclei and remained Methods: A sample of 41 patients with schizophrenia significant when only patients who had never been ex- (32 men and 9 women) and 60 healthy volunteers (45 posed to neuroleptic medication (n=15) were consid- men and 15 women) underwent assessment with high- ered. For the MDN, women had larger relative volumes resolution 1.2-mm thick anatomical MRI. Images were than men among controls, but men had larger volumes differentiated to enhance the edges and outline of the than women among schizophrenic patients. whole thalamus, and the MDN, PUL, and CMN were out- lined on all slices by a tracer masked to diagnostic Conclusions: Three association regions of the thala- status. -
ON-LINE FIG 1. Selected Images of the Caudal Midbrain (Upper Row
ON-LINE FIG 1. Selected images of the caudal midbrain (upper row) and middle pons (lower row) from 4 of 13 total postmortem brains illustrate excellent anatomic contrast reproducibility across individual datasets. Subtle variations are present. Note differences in the shape of cerebral peduncles (24), decussation of superior cerebellar peduncles (25), and spinothalamic tract (12) in the midbrain of subject D (top right). These can be attributed to individual anatomic variation, some mild distortion of the brain stem during procurement at postmortem examination, and/or differences in the axial imaging plane not easily discernable during its prescription parallel to the anterior/posterior commissure plane. The numbers in parentheses in the on-line legends refer to structures in the On-line Table. AJNR Am J Neuroradiol ●:●●2019 www.ajnr.org E1 ON-LINE FIG 3. Demonstration of the dentatorubrothalamic tract within the superior cerebellar peduncle (asterisk) and rostral brain stem. A, Axial caudal midbrain image angled 10° anterosuperior to posteroinferior relative to the ACPC plane demonstrates the tract traveling the midbrain to reach the decussation (25). B, Coronal oblique image that is perpendicular to the long axis of the hippocam- pus (structure not shown) at the level of the ventral superior cerebel- lar decussation shows a component of the dentatorubrothalamic tract arising from the cerebellar dentate nucleus (63), ascending via the superior cerebellar peduncle to the decussation (25), and then enveloping the contralateral red nucleus (3). C, Parasagittal image shows the relatively long anteroposterior dimension of this tract, which becomes less compact and distinct as it ascends toward the thalamus. ON-LINE FIG 2. -
Orienting Head Movements Resulting from Electrical Microstimulation of the Brainstem Tegmentum in the Barn Owl
The Journal of Neuroscience, January 1993, 13(l): 351370 Orienting Head Movements Resulting from Electrical Microstimulation of the Brainstem Tegmentum in the Barn Owl Tom Masino and Eric I. Knudsen Department of Neurobiology, Stanford University, Stanford, California 943055401 The size and direction of orienting movements are repre- movement latency, duration, velocity, and size each dem- sented systematically as a motor map in the optic tectum of onstrated dependencies on stimulus amplitude, frequency, the barn owl (du Lac and Knudsen, 1990). The optic tectum and duration. projects to several distinct regions in the medial brainstem The data demonstrate directly that at the level of the mid- tegmentum, which in turn project to the spinal cord (Masino brain tegmentum there exists a three-dimensional Cartesian and Knudsen, 1992). This study explores the hypothesis that representation of head-orienting movements such that hor- a fundamental transformation in the neural representation izontal, vertical, and roll components of movement are en- of orienting movements takes place in the brainstem teg- coded by anatomically distinct neural circuits. The data sug- mentum. Head movements evoked by electrical microstim- gest that in the projection from the optic tectum to these ulation in the brainstem tegmentum of the alert barn owl were medial tegmental regions, the topographic code for orienting cataloged and the sites of stimulation were reconstructed movement that originates in the tectum is transformed into histologically. Movements elicited from the brainstem teg- this Cartesian code. mentum were categorized into one of six different classes: [Key words: optic tectum, superior colliculus, saccadic saccadic head rotations, head translations, facial move- head movement, brainstem tegmentum, interstitial nucleus ments, vocalizations, limb movements, and twitches. -
Brainstem Dysfunction in Critically Ill Patients
Benghanem et al. Critical Care (2020) 24:5 https://doi.org/10.1186/s13054-019-2718-9 REVIEW Open Access Brainstem dysfunction in critically ill patients Sarah Benghanem1,2 , Aurélien Mazeraud3,4, Eric Azabou5, Vibol Chhor6, Cassia Righy Shinotsuka7,8, Jan Claassen9, Benjamin Rohaut1,9,10† and Tarek Sharshar3,4*† Abstract The brainstem conveys sensory and motor inputs between the spinal cord and the brain, and contains nuclei of the cranial nerves. It controls the sleep-wake cycle and vital functions via the ascending reticular activating system and the autonomic nuclei, respectively. Brainstem dysfunction may lead to sensory and motor deficits, cranial nerve palsies, impairment of consciousness, dysautonomia, and respiratory failure. The brainstem is prone to various primary and secondary insults, resulting in acute or chronic dysfunction. Of particular importance for characterizing brainstem dysfunction and identifying the underlying etiology are a detailed clinical examination, MRI, neurophysiologic tests such as brainstem auditory evoked potentials, and an analysis of the cerebrospinal fluid. Detection of brainstem dysfunction is challenging but of utmost importance in comatose and deeply sedated patients both to guide therapy and to support outcome prediction. In the present review, we summarize the neuroanatomy, clinical syndromes, and diagnostic techniques of critical illness-associated brainstem dysfunction for the critical care setting. Keywords: Brainstem dysfunction, Brain injured patients, Intensive care unit, Sedation, Brainstem -
Imaging the Centromedian Thalamic Nucleus Using Quantitative Susceptibility Mapping
UC Berkeley UC Berkeley Previously Published Works Title Imaging the Centromedian Thalamic Nucleus Using Quantitative Susceptibility Mapping. Permalink https://escholarship.org/uc/item/7pm0m9bk Authors Li, Jun Li, Yufei Gutierrez, Lorenzo et al. Publication Date 2019 DOI 10.3389/fnhum.2019.00447 Peer reviewed eScholarship.org Powered by the California Digital Library University of California BRIEF RESEARCH REPORT published: 09 January 2020 doi: 10.3389/fnhum.2019.00447 Imaging the Centromedian Thalamic Nucleus Using Quantitative Susceptibility Mapping Jun Li 1†, Yufei Li 2†, Lorenzo Gutierrez 2, Wenying Xu 1, Yiwen Wu 3, Chunlei Liu 4,5, Dianyou Li 1, Bomin Sun 1, Chencheng Zhang 1* and Hongjiang Wei 2* 1Department of Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China, 2Institute for Medical Imaging Technology, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China, 3Department of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, Edited by: China, 4Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, Berkeley, CA, United 5 Adolfo Ramirez-Zamora, States, Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA, United States University of Florida Health, United States The centromedian (CM) nucleus is an intralaminar thalamic nucleus that is considered as Reviewed by: a potentially effective target of deep brain stimulation (DBS) and ablative surgeries for the Wolf-Julian Neumann, Charité Medical University of Berlin, treatment of multiple neurological and psychiatric disorders. However, the structure of Germany CM is invisible on the standard T1- and T2-weighted (T1w and T2w) magnetic resonance Zhijiang Wang, Peking University Sixth Hospital, images, which hamper it as a direct DBS target for clinical applications. -
Isolated Necrosis of Central Tegmental Tracts Due to Neonatal Hypoxic-Ischemic Encephalopathy: MRI Findings
Journal of Neurology & Stroke Case Report Open Access Isolated necrosis of central tegmental tracts due to neonatal hypoxic-ischemic encephalopathy: MRI findings Abstract Volume 11 Issue 1 - 2021 Perinatal hypoxia is an old entity that still prevails today and may lead to neurological Tomás de Andrade Lourenção Freddi, Luiz sequelae that can go unnoticed until a certain age, generating many costs for public health. In this case report, we demonstrate on magnetic resonance imaging an unusual pattern of Fellipe Curvêlo Ciraulo Santos, Nelson Paes perinatal hypoxia in a preterm 5-month-old infant, involving the central tegmental tracts Fortes Diniz Ferreira, Felipe Diego Gomes and briefly discuss its possible pathophysiology. Dantas Department of Radiology, Hospital do Coração, Brazil Keywords: magnetic resonance imaging, asphyxia, hypoxic-ischemic encephalopathy, tegmentum, neonates, brainstem Correspondence: Tomás de Andrade Lourenção Freddi, Hospital do Coração, 147 Desembargador Eliseu Guilherme Street, São Paulo, SP, 04004-030, Brazil, Tel +5511976059280, Email Received: May 25, 2020 | Published: Febrauary 15, 2021 Abbreviations: MRI, magnetic resonance imaging; HII, that connect the red nucleus and the inferior olivary nucleus, being hypoxic-ischemic injury; FLAIR, fluid-attenuated inversion recovery; part of the dentato-rubro-olivary system, called Guillain–Mollaret CTT, central tegmental tract; VGB, vigabatrin triangle.3–5 Introduction Hypoxic-ischemic injury (HII) is one of the most important causes of encephalopathy in neonates, irrespective of gestational age, and may occur in the uterus or during delivery by different intrapartum conditions. In preterm or very low birth weight infants, brain magnetic resonance imaging (MRI) can demonstrate multiple different findings, which a detailed description is beyond the scope of this article, although being periventricular leukomalacia the most frequent (seen in at least 50% of cases).