DOCSLIB.ORG

Correlation of Midbrain Diameter and Gait Disturbance in Patients With

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Correlation of Midbrain Diameter and Gait Disturbance in Patients With 0958_0963_Lee_JON_1791 08.08.2005 07:34 Uhr Seite 958 J Neurol (2005) 252:958–963 DOI 10.1007/s00415-005-0791-2 ORIGINAL COMMUNICATION Phil Hyu Lee Correlation of midbrain diameter and gait Suk Woo Yong Yo ung Hwan Ahn disturbance in patients with idiopathic Kyoon Huh normal pressure hydrocephalus ■ Received: 13 July 2004 Abstract Background and pur- significantly smaller in the NPH Received in revised form: pose Although gait disturbance is group than in the controls 19 November 2004 an important feature of idiopathic (14.8 ± 0.9 vs. 17.1 ± 0.7 mm, Accepted: 13 December 2004 normal pressure hydrocephalus p < 0.001). There were inverse cor- Published online: 19 April 2005 (NPH), only tentative theories have relations between the midbrain di- been offered to explain its patho- ameter and the widths of the two physiology. It has been suggested ventricles (r = –0.562, p = 0.008 for that the mesencephalic locomotor the third ventricle, and r = –0.510, region is the anatomical substrate p = 0.018 for the lateral ventricle). for the development of the hypoki- The severity of gait disturbance netic NPH gait. To investigate this was negatively correlated with the possibility, we evaluated the corre- midbrain diameter (r = –0.598, lation between gait disturbance p = 0.004), but the degree of cogni- and midbrain diameter. Methods tive dysfunction and incontinence We enrolled 21 patients with NPH showed no significant correlation P. H . Le e, M.D., Ph.D. (౧) · S. W.Yong, M.D. · and 20 age-matched control sub- with midbrain diameter or ventric- K. Huh, M.D. jects for the study. The maximal di- ular width. Conclusions This study Dept. of Neurology, College of Medicine Ajou University ameter of the midbrain and pons, suggests that midbrain atrophy is Woncheon-dong San 5, Paldal-ku and the width of the lateral and significantly associated with gait Suwon, Kyungki-do, 442–749, South Korea third ventricles were measured us- disturbance in NPH. Tel.: +82-31/219-5174 ing midsagittal T1-weighted MRI Fax: +82-31/219-5178 ■ E-Mail: [email protected] and axial T2-weighted MRI, respec- Key words normal pressure tively. Gait disturbance, cognitive hydrocephalus · midbrain · gait Y. H. Ahn, M.D., Ph.D. Dept. of Neurosurgery dysfunction, and incontinence disturbance · mesencephalic Ajou University School of Medicine were semiquantified. Results The locomotor region Suwon, Korea maximal midbrain diameter was The clinical elements of the NPH gait can be summa- Introduction rized as a hypokinetic gait which is characterized by di- minished gait velocity, reduced stride length, reduced Idiopathic normal pressure hydrocephalus (NPH) is step height, and dynamic disequilibrium [17, 28, 31, 34]. characterized by the clinical triad of gait disturbance, Patients with many other neurodegenerative diseases, progressive cognitive dysfunction, and urinary inconti- such as Parkinson’s disease, subcortical arteriosclerotic nence. Radiological investigations typically reveal en- encephalopathy, progressive supranuclear palsy (PSP), largement of the ventricles without cortical atrophy [2, and corticobasal degeneration, may develop hypoki- 10].Gait disturbance is the first clinical manifestation in netic gait during the disease progression [4, 35, 37]. The most cases of NPH and is one of the most important question of how gait disturbances develop in NPH pa- JON 1791 symptoms [5, 9, 24]. tients remains unresolved. Some researchers have pos- 0958_0963_Lee_JON_1791 08.08.2005 07:34 Uhr Seite 959 959 tulated that frontal lobe dysfunction plays a major role, tio of the greatest distance between the lateral walls in the frontal horns of the first and second ventricles, and the diameter of the inner while others have suggested that hydrocephalus con- table of the skull, both in the transverse plane) was calculated on T1- tributes to the interruption of the subcortical circuit weighted imaging. The maximal diameter of the midbrain and pons connecting the frontal lobe and basal ganglia [3, 19, 28]. was measured on T1-weighted imaging of the midsagittal plane with Based on recent animal studies, the mesencephalic the scanners’internal measurement device [39],using the PiView sys- locomotor region, which plays a major role in locomo- tem program (Fig. 1A). Since maximal ventricular width is known to be well correlated with ventricular volume [38], we measured the tion, has been suggested as the anatomical substrate for width of the lateral ventricle (horizontal distance at the midpoint of the development of gait freezing in idiopathic Parkin- the anteroposterior ventricular scan at the level of the septum pellu- son’s disease and other parkinsonisms [7, 23, 30]. In hu- cidum) on T2-weighted axial images (Fig. 1B). The diameter of the mans, the mesencephalic locomotor region is located in third ventricle was determined by the maximum transverse diameter on axial scans (Fig. 1C). Two neurologists (L. P.H and Y.S.U) mea- the dorsolateral portion of the midbrain [8]. sured the widths of each image in a blinded fashion, and the average In the present study, we assessed the midbrain diam- value was obtained. eter in patients with NPH and analyzed the relationship between the midbrain diameter and gait disturbance to ■ evaluate the contribution of midbrain to NPH gait. Rating scales of NPH symptoms The degree of gait disturbance was semiquantified according to the scale developed by Larsson et al. [22]: 1, normal; 2, insecure; 3, inse- Patients and methods cure with cane; 4, bimanual support; 5, aided; 6, wheelchair. The de- gree of urinary incontinence was recorded semiquantitatively, based ■ Patient population and controls on the scale developed by Krauss et al. [18]: 0, none; 1, sporadic in- continence or urge phenomena; 2,frequent incontinence; 3,only min- Twenty-one NPH patients who were inpatients in the Department of imal control.The degree of cognitive impairment was also semiquan- Neurology and Neurosurgery at Ajou University Hospital from Janu- tified according to the scale of Krauss et al.[20,22]: 0,none; 1,minimal ary, 2001, to April, 2004, were enrolled in the study. The diagnosis of attention or memory deficits; 2, considerable deficits, but oriented to NPH was based on the presence of the following symptoms and signs: situational context; 3, not or only marginally oriented. (1) gait disturbance, (2) cognitive dysfunction, urinary disturbance, or both, (3) ventricular enlargement (Evans ratio > 0.31) without cor- ■ tical atrophy on brain magnetic resonance imaging (MRI) [31],(4) in- Statistical Analysis tracranial pressure below 20 CmH20, as measured by lumbar punc- ture, (5) ventricular filling and block of convexity flow on Statistical analyses were performed with the use of a commercially radionuclide cisternography, (6) absence of other neurological dis- available software package (SPSS, version 10.0). The diameters of the eases that could explain the symptoms, such as progressive supranu- pons and midbrain of patients with NPH and controls were compared clear palsy (PSP) or corticobasal degeneration, or ventricular en- using the Mann-Whitney U test. The Spearman’s correlation test was largement described above [10, 21]. The control group consisted of used to test for associations between the midbrain size and the degree age- and sex-matched healthy volunteers who were free of neurolog- of clinical symptoms of NPH. To determine the interobserver relia- ical disease and whose neurological examinations were normal. bility of the rating, a Cronbach’s alpha coefficient was calculated. P values less than 0.05 were considered statistically significant. ■ Brain MRI and measurements Routine MRI images of the brain were obtained for all subjects on a 1.5-T Signa Scanner (GE, Signa, Advantage). The Evans ratio (the ra- ABC Fig. 1 (A) Measurement of the midsagittal maximal anteroposterior diameter of the midbrain (solid line) and pons (dotted line) on sagittal T1-weighted MR images using the internal measurement device. (B) Maximum lateral ventricle width (solid line) determined where the septum pellucidum remains thin. (C) The maximal third ventricle width (solid line) 0958_0963_Lee_JON_1791 08.08.2005 07:34 Uhr Seite 960 960 Results the diameter of the third ventricle and the diameter of the midbrain (r = –0.562, p = 0.008; Fig. 3A). In addition, The mean age of the patients with NPH was 70.5 years the diameter of the lateral ventricle was inversely corre- (SD 5.6),and 9 (42.8%) were female.The mean age of the lated with the diameter of the midbrain (r = –0.510, healthy control subjects (73.5 years, SD 4.9) was not sta- p = 0.018; Fig. 3B). tistically different from that of patients with NPH, and 9 Among the major symptoms of NPH, only the sever- (45%) were female. All patients with NPH had under- ity of gait disturbance showed an inverse correlation gone radionuclide cisternography that had confirmed with the midbrain diameter (r = –0.598,p = 0.004; Fig. 4); communicating hydrocephalus. All patients with NPH no association was found between urinary incontinence performed the CSF drainage, which subjectively im- or cognitive dysfunction and the midbrain diameter. No proved gait in all patients. The mean of the Evans ratio significant correlation was found between gait disturb- in patients with NPH was 0.39 (SD 0.03). The reliability ance, urinary incontinence, or cognitive dysfunction coefficients for the width of ventricle and maximal mid- with the diameters of the lateral or third ventricle. sagittal diameter of midbrain and pons were as follows: the lateral ventricle, 0.98; the third ventricle, 0.982; the midbrain, 0.975; the pons, 0.979. A The degree of gait disturbance was rated at level 1 in four patients, level 2 in nine patients, level 3 in three pa- tients, level 4 in two patients, level 5 in one patient, and level 6 in two patients.Urinary incontinence was present at level 0 in eight patients, level 1 in six patients, level 2 in five patients,and level 3 in two patients.The degree of cognitive impairment was level 0 in ten patients, level 1 in four patients, level 2 in seven patients, and level 3 in no patients.
Load more

Recommended publications
  • L4-Physiology of Motor Tracts.Pdf
    : chapter 55 page 667 Objectives (1) Describe the upper and lower motor neurons. (2) Understand the pathway of Pyramidal tracts (Corticospinal & corticobulbar tracts). (3) Understand the lateral and ventral corticospinal tracts. (4) Explain functional role of corticospinal & corticobulbar tracts. (5) Describe the Extrapyramidal tracts as Rubrospinal, Vestibulospinal, Reticulospinal and Tectspinal Tracts. The name of the tract indicate its pathway, for example Corticobulbar : Terms: - cortico: cerebral cortex. Decustation: crossing. - Bulbar: brainstem. Ipsilateral : same side. *So it starts at cerebral cortex and Contralateral: opposite side. terminate at the brainstem. CNS influence the activity of skeletal muscle through two set of neurons : 1- Upper motor neurons (UMN) 2- lower motor neuron (LMN) They are neurons of motor cortex & their axons that pass to brain stem and They are Spinal motor neurons in the spinal spinal cord to activate: cord & cranial motor neurons in the brain • cranial motor neurons (in brainstem) stem which innervate muscles directly. • spinal motor neurons (in spinal cord) - These are the only neurons that innervate - Upper motor neurons (UMN) are the skeletal muscle fibers, they function as responsible for conveying impulses for the final common pathway, the final link voluntary motor activity through between the CNS and skeletal muscles. descending motor pathways that make up by the upper motor neurons. Lower motor neurons are classified based on the type of muscle fiber the innervate: There are two UMN Systems through which 1- alpha motor neurons (UMN) control (LMN): 2- gamma motor neurons 1- Pyramidal system (corticospinal tracts ). 2- Extrapyramidal system The activity of the lower motor neuron (LMN, spinal or cranial) is influenced by: 1.
    [Show full text]
  • Microstimulation of the Midbrain Tegmentum Creates Learning Signals for Saccade Adaptation
    The Journal of Neuroscience, April 4, 2007 • 27(14):3759–3767 • 3759 Behavioral/Systems/Cognitive Microstimulation of the Midbrain Tegmentum Creates Learning Signals for Saccade Adaptation Yoshiko Kojima, Kaoru Yoshida, and Yoshiki Iwamoto Department of Neurophysiology, Doctoral Program in Kansei Behavioral and Brain Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8574, Japan Error signals are vital to motor learning. However, we know little about pathways that transmit error signals for learning in voluntary movements. Here we show that microstimulation of the midbrain tegmentum can induce learning in saccadic eye movements in mon- keys. Weak electrical stimuli delivered ϳ200 ms after saccades in one horizontal direction produced gradual and marked changes in saccade gain. The spatial and temporal characteristics of the produced changes were similar to those of adaptation induced by real visual error. When stimulation was applied after saccades in two different directions, endpoints of these saccades gradually shifted in the same direction in two dimensions. We conclude that microstimulation created powerful learning signals that dictate the direction of adaptive shift in movement endpoints. Our findings suggest that the error signals for saccade adaptation are conveyed in a pathway that courses through the midbrain tegmentum. Key words: motor learning; electrical stimulation; midbrain; saccade; adaptation; macaque; monkey Introduction superior colliculus, a key midbrain structure that issues saccade Motor learning ensures the accuracy of the movements we exe- signals to the premotor reticular circuitry (Scudder et al., 2002). cute daily. Vital to learning is the information about the error that The colliculus also has indirect access to the cerebellum via both results from executed movements.
    [Show full text]
  • Brain Structure and Function Related to Headache
    Review Cephalalgia 0(0) 1–26 ! International Headache Society 2018 Brain structure and function related Reprints and permissions: sagepub.co.uk/journalsPermissions.nav to headache: Brainstem structure and DOI: 10.1177/0333102418784698 function in headache journals.sagepub.com/home/cep Marta Vila-Pueyo1 , Jan Hoffmann2 , Marcela Romero-Reyes3 and Simon Akerman3 Abstract Objective: To review and discuss the literature relevant to the role of brainstem structure and function in headache. Background: Primary headache disorders, such as migraine and cluster headache, are considered disorders of the brain. As well as head-related pain, these headache disorders are also associated with other neurological symptoms, such as those related to sensory, homeostatic, autonomic, cognitive and affective processing that can all occur before, during or even after headache has ceased. Many imaging studies demonstrate activation in brainstem areas that appear specifically associated with headache disorders, especially migraine, which may be related to the mechanisms of many of these symptoms. This is further supported by preclinical studies, which demonstrate that modulation of specific brainstem nuclei alters sensory processing relevant to these symptoms, including headache, cranial autonomic responses and homeostatic mechanisms. Review focus: This review will specifically focus on the role of brainstem structures relevant to primary headaches, including medullary, pontine, and midbrain, and describe their functional role and how they relate to mechanisms
    [Show full text]
  • (Rmtg),&Nbsp;A Gabaergic Afferent to Midbrain Dopamine Neurons
    Neuron Article The Rostromedial Tegmental Nucleus (RMTg), a GABAergic Afferent to Midbrain Dopamine Neurons, Encodes Aversive Stimuli and Inhibits Motor Responses Thomas C. Jhou,1,* Howard L. Fields,2 Mark G. Baxter,3 Clifford B. Saper,4 and Peter C. Holland5 1Behavioral Neuroscience Branch, National Institute on Drug Abuse, Baltimore, MD 21224, USA 2Ernest Gallo Clinic and Research Center, University of California at San Francisco, Emeryville, CA 94608, USA 3Department of Experimental Psychology, University of Oxford, OX1 3UD Oxford, UK 4Beth Israel Deaconess Medical Center, Harvard University, Boston, MA 02215, USA 5Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA *Correspondence: [email protected] DOI 10.1016/j.neuron.2009.02.001 SUMMARY vation strongly inhibits dopamine (DA) neurons (Christoph et al., 1986; Ji and Shepard, 2007), are activated by aversive Separate studies have implicated the lateral habe- stimuli and reward omission and inhibited by reward-predictive nula (LHb) or amygdala-related regions in processing cues or unexpected rewards (Matsumoto and Hikosaka, 2007, aversive stimuli, but their relationships to each other 2009; Geisler and Trimble, 2008). These ‘‘negative reward and to appetitive motivational systems are poorly prediction errors’’ are inverse to firing patterns in putative dopa- understood. We show that neurons in the recently minergic midbrain neurons (Mirenowicz and Schultz, 1994, 1996; identified GABAergic rostromedial tegmental Hollerman and Schultz, 1998;
    [Show full text]
  • 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.
    [Show full text]
  • Why a Midbrain? Evolution, Structure and Functions Notes
    The changes cause "distortions" in the basic organization of the hindbrain • Variations in relative size of parts – Huge vagal lobe of the fresh-water buffalofish [Review] – Vagal and facial lobes of the catfish [Review] – Electric fish have an enormous and specialized cerebellum. [Review] • Cell migrations from the rostral hindbrain’s alar plate— from a proliferative region called the “rhombic lip”: – To cerebellum – To pre-cerebellar cell groups – especially the cells of the pons 1 Endbrain Midbrain Cerebellum Vagal Lobe Image by MIT OpenCourseWare. Buffalofish (Carpiodes tumidus) has a specialized palatal organ for filtering the water for food; it is innervated by the vagus nerve. 2 Olfactory Stalk Primitive Endbrain Midbrain Cerebellum Facial Lobe Vagal Lobe Image by MIT OpenCourseWare. The catfish has taste receptors all over its body innervated by the facial nerve (7th cranial nerve) 3 Amiurus melas (the small catfish) Image by MIT OpenCourseWare. 4 Courtesy of MIT Press. Used with permission. Schneider, G. E. Brain structure and its Origins: In the Development and in Evolution of Behavior and the Mind. MIT Press, 2014. ISBN: 9780262026734. The enlarged cerebellum of a Mormyrid fish Fig.6-1 5 Questions, chapter 10 16) What is the meaning of the term “pons”? (See the end of chapter 5.) What is a major input, and what is the major output, of the cells of the pontine gray matter? 17) What causes quantitative distortions of the basic structural layout of the hindbrain? What is the major distortion that occurs in the development of the hindbrain of humans and other primates? 18) What is the role of the “rhombic lip” – a structure seen during the development of the rostral hindbrain? 6 The "distortions" in the basic organization of the hindbrain, continued • Variations in relative size of parts √ Huge vagal lobe of the fresh-water buffalofish √ Vagal and facial lobes of the catfish √ Electric fish have an enormous and specialized cerebellum.
    [Show full text]
  • Localization and Network of Coma- Causing Brainstem Lesions: Evidence for a Human Consciousness Network
    Localization and Network of Coma- Causing Brainstem Lesions: Evidence for a Human Consciousness Network The Harvard community has made this article openly available. Please share how this access benefits you. Your story matters Citation Fischer, David B. 2016. Localization and Network of Coma-Causing Brainstem Lesions: Evidence for a Human Consciousness Network. Doctoral dissertation, Harvard Medical School. Citable link http://nrs.harvard.edu/urn-3:HUL.InstRepos:27007725 Terms of Use This article was downloaded from Harvard University’s DASH repository, and is made available under the terms and conditions applicable to Other Posted Material, as set forth at http:// nrs.harvard.edu/urn-3:HUL.InstRepos:dash.current.terms-of- use#LAA Abstract Focal brainstem lesions can disrupt arousal and cause coma, yet the exact location of the brainstem region critical to arousal and its associated network are unknown. First, we compare brainstem lesions between 12 patients with coma and 24 patients without coma to identify a region specific to coma-causing lesions. Second, we determine the network connectivity of this brainstem region and each individual coma- causing lesion using resting state functional connectivity MRI data acquired from 98 healthy subjects. Third, we evaluate the functional connectivity of this network in patients with disorders of consciousness (51 patients versus 21 controls). These analyses reveal a small, coma-specific region in the left pontine tegmentum, near the medial parabrachial nucleus. This brainstem region, and each individual coma-causing lesion, is functionally connected to the left agranular, anterior insula (AI), and pregenual anterior cingulate cortex (pACC). These cortical sites align poorly with previously defined functional networks but match the distribution of von Economo neurons (VENs).
    [Show full text]
  • Chapter 3: Internal Anatomy of the Central Nervous System
    10353-03_CH03.qxd 8/30/07 1:12 PM Page 82 3 Internal Anatomy of the Central Nervous System LEARNING OBJECTIVES Nuclear structures and fiber tracts related to various functional systems exist side by side at each level of the After studying this chapter, students should be able to: nervous system. Because disease processes in the brain • Identify the shapes of corticospinal fibers at different rarely strike only one anatomic structure or pathway, there neuraxial levels is a tendency for a series of related and unrelated clinical symptoms to emerge after a brain injury. A thorough knowl- • Recognize the ventricular cavity at various neuroaxial edge of the internal brain structures, including their shape, levels size, location, and proximity, makes it easier to understand • Recognize major internal anatomic structures of the their functional significance. In addition, the proximity of spinal cord and describe their functions nuclear structures and fiber tracts explains multiple symp- toms that may develop from a single lesion site. • Recognize important internal anatomic structures of the medulla and explain their functions • Recognize important internal anatomic structures of the ANATOMIC ORIENTATION pons and describe their functions LANDMARKS • Identify important internal anatomic structures of the midbrain and discuss their functions Two distinct anatomic landmarks used for visual orientation to the internal anatomy of the brain are the shapes of the • Recognize important internal anatomic structures of the descending corticospinal fibers and the ventricular cavity forebrain (diencephalon, basal ganglia, and limbic (Fig. 3-1). Both are present throughout the brain, although structures) and describe their functions their shape and size vary as one progresses caudally from the • Follow the continuation of major anatomic structures rostral forebrain (telencephalon) to the caudal brainstem.
    [Show full text]
  • Cholinergic System and NGF Receptors: Insights from the Brain of the Short-Lived Fish Nothobranchius Furzeri
    brain sciences Article Cholinergic System and NGF Receptors: Insights from the Brain of the Short-Lived Fish Nothobranchius furzeri Paolo de Girolamo 1,*, Adele Leggieri 1 , Antonio Palladino 2 , Carla Lucini 1 , Chiara Attanasio 1 and Livia D’Angelo 1 1 Department Veterinary Medicine and Animal Production, University of Naples Federico II, Naples I-80137, Italy; [email protected] (A.L.); [email protected] (C.L.); [email protected] (C.A.); [email protected] (L.D.) 2 CESMA—Centro Servizi metereologici e Tecnologici Avanzati, University of Naples Federico II, I-80126 Naples, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-081-2536099 Received: 31 May 2020; Accepted: 17 June 2020; Published: 20 June 2020 Abstract: Nerve growth factor (NGF) receptors are evolutionary conserved molecules, and in mammals are considered necessary for ensuring the survival of cholinergic neurons. The age-dependent regulation of NTRK1/NTRKA and p75/NGFR in mammalian brain results in a reduced response of the cholinergic neurons to neurotrophic factors and is thought to play a role in the pathogenesis of neurodegenerative diseases. Here, we study the age-dependent expression of NGF receptors (NTRK1/NTRKA and p75/NGFR) in the brain of the short-lived teleost fish Nothobranchius furzeri. We observed that NTRK1/NTRKA is more expressed than p75/NGFR in young and old animals, although both receptors do not show a significant age-dependent change. We then study the neuroanatomical organization of the cholinergic system, observing that cholinergic fibers project over the entire neuroaxis while cholinergic neurons appear restricted to few nuclei situated in the equivalent of mammalian subpallium, preoptic area and rostral reticular formation.
    [Show full text]
  • Midbrain Tegmental Lesions Affecting Or Sparing the Pupillary Fibres
    J7ournal ofNeurology, Neurosurgery, and Psychiatry 1996;61:401-402 401 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.61.4.401 on 1 October 1996. Downloaded from SHORT REPORT Midbrain tegmental lesions affecting or sparing the pupillary fibres Naokatsu Saeki, Naohisa Murai, Kenro Sunami Abstract lesion in the upper midbrain and close to the Two patients with oculomotor palsy third ventricle (fig 1). caused by midbrain infarction are Three months later the oculomotor palsy reported. In the first, pupillary reaction improved. The patient returned to his previ- was affected and in the second this reac- ous work after a further three months. tion was spared. Because the lesions in the anterior part of the tegmentum were CASE 2 in the upper midbrain in the first patient A 68 year old woman with hypertension for and in the lower midbrain in the second, eight years suddenly developed vertigo and it is suggested that the pupillary compo- nents of the oculomotor nerve are located in the upper midbrain. (7 Neurol Neurosurg Psychiatry 1996;61:401-402) Keywords: midbrain; oculomotor nerve; pupil sparing We report the details of two patients with a small midbrain infarction, the first with impairment of pupillary reaction to light and the second in which this reaction was pre- served. The aim of this study was to elucidate the topography of oculomotor pupillary fibres in the midbrain tegmentum based on findings using MRI. http://jnnp.bmj.com/ Case studies CASE 1 A 67 year old man with a 10 year history of hypertension presented with difficulty in open- ing his left eye on waking up in the morning.
    [Show full text]
  • Brain Stem  Consists: - Medulla Oblongata - Pons - Midbrain (Mesencephalon)
    Brain Stem Consists: - Medulla oblongata - Pons - Midbrain (Mesencephalon) Lies upon the basal portion of occipital bone (clivus) and is connected to cerebellum rostral : diencephalon caudal : spinal cord Contains numerous ascending and descending fibre tracts Brain stem nuclei receive fibres from or sent fibres into cranial nerves (III-XII) attach to the surface of the brain stem cranial nerve nuclei Ascenden and Descenden Pathway of Brain Stem Ascenden Descenden Lemniscus medialis Traktus corticospinalis Tractus spinothalamicus Tractus corticonuclearis Lemniscus trigeminalis Corticopontine fibres Lemniscus lateralis Tractus rubrospinalis Reticularis fibres system Tractus tectospinalis Fasciculus longitudinalis medialis Fasciculuc longitudinal medialis Pedunculus cerebellaris superior Tractus vestibulospinalis Pedunculus cerebellaris inferior Tractus reticulospinalis Secondary vestibularis fibres Tractus tegmentalis centralis Secondary gustatorius fibres Tractus descenden N.V Brain Stem Contains a complex and heterogeneous matrix of neurones reticular formation functions : - control over the level of consciousness - the perception of pain - regulation of the cardiovascular and respiratory systems It also has extensive connections with cranial nerve nuclei, cerebellum, brain stem and spinal motor mechanisms movement, posture and muscle tone Dorsal Surface (External Feature) Peduncles Dorsal median sulcus Dorsal columns (fasciculi gracilis and cuneatus) Gracile and cuneate tubercles (nuclei gracilis and cuneatus) Fossa rhomboidea
    [Show full text]
  • The Pons Neurological System > Brainstem & Cranial Nerve Anatomy > Brainstem & Cranial Nerve Anatomy
    The Pons Neurological System > Brainstem & Cranial Nerve Anatomy > Brainstem & Cranial Nerve Anatomy THE PONS OVERVIEW Here, we'll learn about the pons. • Start a table. • Denote that, from a clinician's perspective, the pons is, most notably, the neurobiological site of injury that produces locked-in syndrome. • Start a mid-sagittal section. First, draw the different brainstem levels, from superior to inferior: • Midbrain • Pons • Medulla KEY SURROUNDING STRUCTRES Label the anterior/posterior orientational plane of our diagram. • Include the key structures that border the brainstem: • The hyopthalamus, superiorly. • The cerebellum, posteriorly. • The cervical spinal cord, inferiorly. • And the temporal lobe, laterally. • Now, point out the pontine basis, which comprises pontine nuclei and pontocerebellar fiber tracts. • Shade in the CSF and indicate that the 4th ventricle lies at the level of the pons. RADIOGRAPHIC AXIAL SECTION • Before we draw a detailed anatomical section, let's review an axial section in radiographic perspective, which is the 1 / 4 common clinical perspective. • Show its anterior/posterior orientational plane. • Draw the pons. • Demarcate the pontine basis, anteriorly. • In this view, show its representative pontine nuclei. • And show its pontocerebellar fibers, which cross the pons and pass into the middle cerebellar peduncle as an important step in the corticopontocerebellar pathway. Clinical Correlation: central pontine myelinolysis ANATOMIC AXIAL SECTION Now, let's draw an anatomic axial outline of the pons. • Indicate the anterior–posterior axis of our diagram. • Label the left side of the page as nuclei and the right side as tracts. • Then, label the fourth ventricle — the cerebrospinal fluid space of the pons. • Next, distinguish the large basis from the comparatively small tegmentum.
    [Show full text]