Surgical Neurology International
Total Page:16
File Type:pdf, Size:1020Kb
SSurgicalurgical NNeurologyeurology IInternationalnternational OPEN ACCESS Editor: Antonio A. F. DeSalles, MD SSNI:NI: SStereotactictereotactic, a ssupplementupplement ttoo SSurgicalurgical NNeurologyeurology IInternationalnternational For entire Editorial Board visit : University of California, http://www.surgicalneurologyint.com Los Angeles, CA, USA Maps of the adult human hypothalamus Jean-Jacques Lemaire1,2, Hachemi Nezzar1,3, Laurent Sakka1,2, Yves Boirie4, Denys Fontaine1,5, Aurélien Coste2, Guillaume Coll2, Anna Sontheimer1, Catherine Sarret1,6, Jean Gabrillargues1,7, Antonio De Salles8 1Univ Clermont 1, UFR Médecine, EA 7282, Image-Guided Clinical Neuroscience and Connectomics, Clermont-Ferrand, F-63001, 2Service de Neurochirurgie, 3Service d’Ophtalmologie, 4Service de Nutrition, 6Service de Pédiatrie, 7Unité de Neuroradiologie, CHU Clermont-Ferrand, Clermont-Ferrand, F-63003, 5Service de Neurochirurgie, CHU de Nice, Nice, F-06200, France, 8Department of Neurosurgery, University of California, Los Angeles, USA E-mail: *Jean-Jacques Lemaire - [email protected]; Hachemi Nezzar - [email protected]; Laurent Sakka - [email protected]; Yves Boirie - [email protected]; Denys Fontaine - [email protected]; Aurélien Coste - [email protected]; Guillaume Coll - [email protected]; Anna Sontheimer - [email protected]; Catherine Sarret - [email protected]; Jean Gabrillargues - [email protected]; Antonio De Salles - [email protected] *Corresponding author Received: 01 February 13 Accepted: 01 February 13 Published: 17 April 13 This article may be cited as: Lemaire J, Nezzar H, Sakka L, Boirie Y, Fontaine D, Coste A, et al. Maps of the adult human hypothalamus. Surg Neurol Int 2013;4:156-63. Available FREE in open access from: http://www.surgicalneurologyint.com/text.asp?2013/4/4/156/110667 Copyright: © 2013 Lemaire J. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Abstract The human hypothalamus is a small deeply located region placed at the crossroad of neurovegetative, neuroendocrine, limbic, and optic systems. Although deep brain stimulation techniques have proven that it could be feasible to modulate these systems, targeting the hypothalamus and in particular specifi c nuclei and white bundles, is still challenging. Our goal was to make a synthesis of relevant topographical data of the human hypothalamus, under the form of magnetic resonance imaging maps useful for mastering its elaborated structure as well as its Access this article neighborhood. As from 1.5 Tesla, Inversion-Recovery sequence allows locating the online hypothalamus and most of its components. Spotting hypothalamic compartments is Website: possible according to specifi c landmarks: the anterior commissure, the mammillary www.surgicalneurologyint.com bodies, the preoptic recess, the infundibular recess, the crest between the preoptic DOI: 10.4103/2152-7806.110667 and the infundibular recesses, the optical tract, the fornix, and the mammillo-thalamic Quick Response Code: bundle. The identifi cation of hypothalamus and most of its components could be useful to allow the quantifi cation of local pathological processes and to target specifi c circuitry to alleviate severe symptoms, using physical or biological agents. Key Words: Brain mapping, hypothalamus, inversion-recovery sequence, magnetic resonance imaging, stereotaxy INTRODUCTION region of the human brain. From a clinical perspective, several reports have proven that hypothalamus The hypothalamus is a small and heterogeneous region of neuromodulation is possible;[10,12,23,26,33,34,50] however, the prosencephalon. It is situated in a strategic position the most important part of the clinical research has to at the crossroad of four systems, neurovegetative, be done before proposing reliable long-term invasive neuroendocrine, limbic, and optic. Its numerous functional treatments. Paradoxically although the functional facets, from behavior to chronobiology, make hypothalamus was extensively explored in several species, the hypothalamus likely one of the most challenging it is still a poorly known region of the deep human brain. S156 SNI: Stereotactic 2013, Vol 4, Suppl 3 - A Supplement to Surgical Neurology International Pioneer’s histological atlas provided details that are often 1.5 Tesla using appropriate sequences.[13] T1-weighted difficult to relate to the clinical context. Our goal was to images allow recognizing the overall morphology of walls make a synthesis of relevant topographical data of the and floor of the third ventricle, as well as the fornix and human hypothalamus, under the form of maps useful for the mammillary bodies Moreover, inversion-recovery mastering its elaborated structure. Magnetic resonance sequences[36,44] enhance the contrast between white and imaging (MRI) was used to create these maps, since it is gray matters, allowing identifying basal ganglia, thalamus the most advanced way to finely explore in a noninvasively and hypothalamus, as well as white matter structures the hypothalamus. This was accomplished using the [Figure 2]. widely available 1.5 Tesla device. Anatomical landmarks The complex organization of hypothalamic nuclei makes were defined to map structures to subject’s peculiarities, it difficult to visualize details of location and shape providing means to further research protocols. of the nuclear heaps. However, it can be made simpler using semi-realistic drawing[43] and 3D reconstruction[32] STRUCTURAL MRI ANATOMY OF THE [Figure 3]. HYPOTHALAMUS Most hypothalamic nuclei are well described, however, The hypothalamus is a double diencephalic structure there are still ambiguous definitions revealing the located within the right and left walls and the floor of incomplete understanding of each nucleus in humans.[15,43] the third ventricle. The pituitary stalk is developed from The group of preoptic nuclei, also named prothalamus, the infundibular recess to the hypophysis or pituitary is the most rostral; it contains the medial and lateral gland. The hypothalamus is placed obliquely in front preoptic nuclei and the anterior nucleus. Behind, medial and below the thalamus, limited posteriorly by the and superficial, lies the thin paraventricular nucleus, subthalamus and the anterior upper brain stem [Figure 1]. placed just under the wall of the third ventricle. This Internal organization of hypothalamus The adult’s hypothalamus has a volume of approximately 0.7 cm3 in each side, as measured on MRI.[43] It is composed of cellular heaps and white matter fibers. The cellular heaps form nuclei, which are regrouped in regions and zones,[15] according to topographic and cytoarchitectural organization. a b The visualization of all hypothalamic nuclei and white matter tracts is not feasible with current clinical imaging; however, several pertinent landmarks are identifiable with c d a b e f g Figure 2: MRI coronal slices (white matter attenuated inversion c recovery sequence; joined slices, matri0.560.56 mm, 2-mm Figure 1: 3D reconstruction of the adult human hypothalamus thickness) from posterior (a) to anterior (g): third ventricle (1), displayed on three orthogonal (a. Frontal view; b. Left lateral view; mammillary body (2), fornix (3), thalamus (4), mammillo-thalamic c. Inferior view) T1-weighted MRI slices crossing the mammillary bundle or Vicq d’Azyr fascicle (5), nucleus entopedoncularis or bodies (light blue): hypothalamus (green plus light blue), anterior nucleus of ansa lenticularis (6), zona incerta (7), optical tract (8), white commissure (purple), thalamus (brown), pallidum (purple), pallidum (9), hypothalamus (10), anterior white commissure (11), third ventricle (yellow; the brain aqueduct and the ventricular optic chiasma (12), internal capsule posterior limb (13), internal foramen are also reconstructed), and optical system (dark blue) capsule anterior limb (14) S157 SNI: Stereotactic 2013, Vol 4, Suppl 3 - A Supplement to Surgical Neurology International a b Figure 3: (a) Schematic drawing of hypothalamic nuclei, lateral view from the midline; left, nuclei directly located under the wall of the third ventricle; right, more deeply located nuclei up to the lateral region. (b) 3D overview of hypothalamic nuclei, constructed from a 3D high-fi eld MRI data set; left, frontal view; intermediate, lateral view; right, medial view; the ventral tegmental area (VTA) is located within the retro hypothalamic region. Anterior commissure, Ac; dorsal or posterior nucleus, D; dorsomedial nucleus, Dm; fornix, Fx; fornix nuclei F; infundibular (arcuate) nucleus, If; lateral nucleus, L; mammillary body, Mb; mammillo-thalamic bundle, Mtb; optic chiasma, Cx; paraventricular nucleus, Pv; preoptic nuclei, Pr; suprachiasmatic (ovoid) nucleus, Sc; ventricular foramen, Vf; supraoptic (tangential) nucleus, So; tuberomamillaris (mamilloinfundibularis) nucleus, Tm; ventromedial (tuber principal) nucleus, Vm latter can also be regrouped with the preoptic group, as limbic system, the basal ganglia, and the thalamus. The well as lateral sparse cells belonging to the lateral nucleus. elements of basal ganglia neighboring the hypothalamus The supraoptic nucleus and the suprachiasmatic nucleus, are the striatum, the medial pallidum, the substantia respectively, lateral and medial,