DOCSLIB.ORG

Falx and Interhemispheric Fissure on Axial CT: I

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Falx and Interhemispheric Fissure on Axial CT: I 175 Falx and Interhemispheric Fissure on Axial CT: I. Normal Anatomy Robert D. Zimmerman 1 To determine the normal appearance of the falx and interhemispheric fissure, 200 Emily Yurberg 1 consecutive normal CT scans were evaluated prospectively. On unenhanced scans, the Eric J. Russel1 2 normal falx is visualized in 90% of patients and therefore interhemispheric hyperdensity alone should not be considered a sign of subarachnoid hemorrhage. The falx is most Norman E. Leeds 1 often (88%) visualized in the posterior part of the interhemispheric fissure, as a hyperdense, pencil-thin line extending from the calvarium to the splenium of the corpus callosum. In the anterior part of the fissure, the falx is visualized in only 38% of patients, when its appearance differs significantly from that of the fissure. It is seen as a thin, hyperdense line extending posteriorly from the calvarium for a variable distance, but it never reaches the genu of the corpus callosum. The interhemispheric fissure is a hypodense structure broader than the falx with a zigzag configuration due to medial frontal sulci. The difference in configuration between the anterior part of the fissure and the anterior falx is very helpful in differentiating subarachnoid hemorrhage from normal falx visualization. The falx cerebri and interhemispheric fissure, although recognized early on axial CT [1], received little attention in the literature. We have studied the normal anatomic configuration of these structures in detail and offer anatomic information for differentiation of a variety of pathologic processes that may affect the fal x and interhemispheric fissure. Materials and Methods Two hundred scans performed without contrast opacification on an EMI 1005 were evaluated prospectively. The consecutive cases were interpreted as norm al or showing This article appears in the March/ April 1982 only involutional changes consistent with age. An y patient with a hi story, physical findings, issue of the AJNR and the May 1982 issue of or laboratory data suggestive of intracranial hemorrh age, trauma, or surgery was eliminated the AJR. from the study even when the scans were interpreted as normal. The patients were aged 8 Received July 17, 1981; accepted after revi­ days to 89 years; there were 96 males and 104 females. sion September 10, 1981 . On axial projection, at 10°- 20 ° to the anthropologic baselin e, the falx and interhemi­ Presented at the annual meeting of the Ameri­ spheric fi ssure are seen as a unit divided into three segments by the interposition of the can Society of Neuroradiology, Los Angeles, curved corpus callosum (fig . 1). Anterior (precallosal), posterior (retrocallosal), and superior March 1980. (supracall osal) segments are identified. Presented at the annual meeting of the Ameri­ The frequency of falx visuali zation on unenhanced scans was determined. Each segment can Roentgen Ray Society, Las Vegas, April 1980. of the falx and interhemispheri c fi ssure was separately analyzed for frequency of visualiza­ , Department of Radiology, Montefiore Hospital tion and appearance. Particular attention was paid to the effect of age on the appearance and Medical Center, 111 E. 21 Oth SI. , Bronx, NY of the falx/ fi ssure combination. The mean and peak density of the fal x on unenhanced 10467. Address reprint requests to R. D. Zimmer­ man. scans was determined for each case. Areas of obvious calcification were excluded from the quantitative analysis. 2 Department of Radiology, Ru sh Presby­ terian -Sl. Luke·s Medical Center, Chicago, IL Contrast opacificati on was studied in 20 of the 200 cases. These were chosen because 60612. pre- and postcontrast scans were obtained at identical levels, all owing determination of the effect of enhancement on falx density and configuration. AJNR 3 :175-180, March/ April 1982 0 195-61 08/ 82/ 0302-0175 $00.00 Anatomic studies were performed on 10 brains bisected at the corpus callosum with the © American Roen tg en Ray Society falx intact. The falx and its relation to the interhemispheric fissure and corpus call osum 176 ZIMMERMAN ET AL. AJNR:3, Marchi April 1982 POSTERIOR FALX VISU ALIZATI ON IoIALE 823"'- FEMALE 93 2 % TOTAL 68.0% ( 9!1) 100 (93.8 1 ( 912 1 ( 9 01 z (81 1, ~ ..>- 80 (751 20° N ::; ..=> <n ;; 60 " 40 0-10 10-20 20·30 30 ·40 4 0 ·50 50·60 60·70 > 70 AGE l yeorsl A Fig. 1.-Drawing of falx and corpus callosum. On axial scans, corpus ANTERIOR FAL X VI SUALIZATION callosum divides fal x and surrounding interhemispheric fissure into anterior (precallosal), posterior (retrocallosal). and superi or (supracall osal) seg ments. Division 01 falx into these segments depends on scanning angle, which does WA LE 39. 6"" 100 not cause significant problems, since changes in lalx and fissure are gradual. FEW"LE 36 ''''' TOTA L 38.0% 80 .... VI SUALIZAT IO N "" VIS UAL IZATION CO RRECTED { 66.7 1 z o FOR 4TROPHY o ( 62.9 ) were examined. Four patients with typical falx visualization on 1601 ~ 60 unenhanced scans died of intercurrent disease, and the fa lx was N ..J evaluated pathologically for presence or absence of calcification . .. ~ :;: 40 ' 33.31 A " " ( 23.5 ) ( 20 ) ,," " (1 7.'1 __ 0 20 Results " ' 0"'" ( 1• •8 ) The falx was visualized in 90% of unenhanced scans. The frequency of visualization of each fal x segment varied sig­ 0·10 10·20 20-30 30-40 40·50 50- 60 60 · 70 > 70 nificantly. The retrocallosal falx was seen in 88% of patients AGE ( years) regardless of age or gender (fig. 2A). It had the character­ B istic and virtually invariable appearance of a pencil-thin, hyperdense line extending from the calvarium to the sple­ SUPFRIOR F"_ ' VISU;"lIZATI,JN nium of the corpus callosum (fig . 3). Anatomic studies .1001 JJ 931 demonstrate that this falx segment is of uniform thickness ,SO) and occupies the entire interhemispheric fissure (fig. 4). In 80 this location, the fissure is extremely narrow and is almost (671 invisible on CT, even in elderly patients with relatively severe Q ::; 0 atrophy affecting other segments of the fissure, especially N ..J its anterior part (figs. 3C and 3D). <C => ( .a s ) <Il 40 1'.1 0 I! 68"4 The anterior or precallosal segment of the falx was iden­ > FemQI ~ 68"4 tified in only 38% of patients with more frequent visualization TOfO I 68"4 in patients over age 40 (fig. 2B). It extended posteriorly 20 from the inner table of th e skull toward the genu of th e corpus callosum for a variable distance. In most cases it o L-------__-- ________-- __-- ~--------- occupied only the anterior one-third to one-half of the inter­ 0·10 10-20 20·30 30·40 40·50 50·60 60-70 --'70 hemispheric fissure, but in the minority of cases, it extended AGE ( ears) further posteriorly, approaching but never reaching the genu c of the corpus callosum. Anatomic studies confirm the vari­ Fig. 2.-'-Rates of visualization of falx. A. Posterior falx visualization not able depth and thickness of this falx segment, which was significantly affected by age. varying between 75% and 95"0. B. By contrast. al\ ays thinnest along its inferior margin where fenestrations anterior fa lx visualization is less frequent. and frequency increases dramati­ were commonly observed (fig. 4). In many specimens a cally (solid line) alter age 40. Increase is due to progressive atrophic dilatation of anterior part of in terhemispheric fissure. When cases in which falx visual­ large gap (fig. 4A) occurred between the thin shallow ante­ ization due to dilatation of anterior interhemispheric subarachnoid space are rior fal and the genu of the corpus callosum. In other cases eliminated. rate of anterior falx visualization does not change with age (dashed Ime). C. Superior falx Shows no consistent change in visualization (fig. 4B) the fal was deep and thick but did not completely rate. e tend to the genu of the corpus callosum. The precallosal part of the interhemispheric fissure was narro\' and only intermittently visible in children and young AJNR:3, March i April 1982 CT OF NORMAL FALX AND INTERHEMISPHERIC FISSURE 177 Fi g. 3. -Normal precallosal and retrocallosal falx and interhemispheric visualized bu t deep falx in B. In all cases, there is gap between free inferior fissure at several ages. Scans in patients aged 3 (A), 22 (B), 46 (C), and 76 margin of falx and genu of corpus callosum (small white arrow). Retrocallosal (D). Typical appearan ce of falx and surrounding fissure in th ese ages. In all segment of interhemispheric fissure so narrow as to be virtually invisible examples, retrocallosal fal x is thin hyperdense line extending from calvarium (A-D), even in face of severe atrophy elsewhere, in particular, anterior part to splenium of corpus callosum (large white arrow). Precallosal part of falx is of interhemi sph eric fissure (C and D) . In these figures, fissure (small black more variable. Anterior falx may be nonvisualized (A) or minimally seen (B) arrows) has configuration of hypodense zigzag line extending from calvarium between frontal lobes (large black arrow). As fissure dilates, falx becomes to genu of corpus callosum . In younger patients, fissure is either not seen (A) more easily seen (large black arrow, C and D) . Depth of an terior part of falx or only intermittently seen as small focal areas of cerebrospinal flu id density varies, as demonstrated by comparing short or shallow falx in C with poorly (small black arrows). Fig. 4. - Anatomic specimens. Bisected cerebral hemispheres with falx call osu m (small arrow). In other specimens (B), precallosal falx is deeper and intact. Uniformly thick and dense posterior falx fills virtuall y entire retrocal­ thicker, but gap remain s between iree margin of fa lx (large arrow) and genu losal interhemispheri c fi ssure.
Load more

Recommended publications
  • Multiple Osteomas of the Falx Cerebri and Anterior Skull Base: Case Report
    CASE REPORT J Neurosurg 124:1339–1342, 2016 Multiple osteomas of the falx cerebri and anterior skull base: case report Khaled M. Krisht, MD,1 Cheryl A. Palmer, MD,2 and William T. Couldwell, MD, PhD1 1Department of Neurosurgery, Clinical Neurosciences Center, and 2Department of Pathology, University of Utah, Salt Lake City, Utah The authors describe a rare case of intracranial extraaxial parafalcine and anterior skull base osteomas in a 22-year- old woman presenting with bifrontal headaches. This case highlights the possible occurrence of such lesions along the anterior skull base and parafalcine region that, as such, should be considered as part of the differential diagnosis for extraaxial calcific lesions involving the anterior skull base. To the authors’ knowledge, this is the first reported case of a patient who underwent complete successful resection of multiple extraaxial osteomas of the anterior skull base and parafalcine region. http://thejns.org/doi/abs/10.3171/2015.6.JNS15865 KEY WORDS osteoma; anterior skull base; parafalcine; falx cerebri; differential; CT; oncology STEOMAS are benign neoplasms consisting of ma- was first evaluated 6 years earlier, undergoing contrast- ture normal osseous tissue. They commonly arise enhancing MRI of the brain that disclosed a nonenhanc- from the long bones of the extremities. In the re- ing extraaxial T1-weighted isointense and T2-weighted Ogion of the head and neck, they are usually limited to the hypointense parafalcine lesion. At her latest presentation paranasal sinuses, facial bones, skull, and mandible.4,5,7 repeat brain MRI with and without contrast enhancement Their etiology is still a matter of debate.
    [Show full text]
  • Human and Nonhuman Primate Meninges Harbor Lymphatic Vessels
    SHORT REPORT Human and nonhuman primate meninges harbor lymphatic vessels that can be visualized noninvasively by MRI Martina Absinta1†, Seung-Kwon Ha1†, Govind Nair1, Pascal Sati1, Nicholas J Luciano1, Maryknoll Palisoc2, Antoine Louveau3, Kareem A Zaghloul4, Stefania Pittaluga2, Jonathan Kipnis3, Daniel S Reich1* 1Translational Neuroradiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States; 2Hematopathology Section, Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, United States; 3Center for Brain Immunology and Glia, Department of Neuroscience, School of Medicine, University of Virginia, Charlottesville, United States; 4Surgical Neurology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, United States Abstract Here, we report the existence of meningeal lymphatic vessels in human and nonhuman primates (common marmoset monkeys) and the feasibility of noninvasively imaging and mapping them in vivo with high-resolution, clinical MRI. On T2-FLAIR and T1-weighted black-blood imaging, lymphatic vessels enhance with gadobutrol, a gadolinium-based contrast agent with high propensity to extravasate across a permeable capillary endothelial barrier, but not with gadofosveset, a blood-pool contrast agent. The topography of these vessels, running alongside dural venous sinuses, recapitulates the meningeal lymphatic system of rodents. In primates, *For correspondence: meningeal
    [Show full text]
  • Duplication of Falx Cerebelli, Occipital Sinus, and Internal Occipital Crest
    Romanian Journal of Morphology and Embryology 2009, 50(1):107–110 ORIGINAL PAPER Duplication of falx cerebelli, occipital sinus, and internal occipital crest SUJATHA D’COSTA, A. KRISHNAMURTHY, S. R. NAYAK, SAMPATH MADHYASTA, LATHA V. PRABHU, JIJI P. J, ANU V. RANADE, MANGALA M. PAI, RAJANIGANDHA VADGAONKAR, C. GANESH KUMAR, RAJALAKSHMI RAI Department of Anatomy, Centre for Basic Sciences, Kasturba Medical College, Bejai, Mangalore, Karnataka, India Abstract The incidence of variations of falx cerebelli was studied in 52 adult cadavers of south Indian origin, at Kasturba Medical College Mangalore, after removal of calvaria. In eight (15.4%) cases, we observed duplicated falx cerebelli along with duplicated occipital sinus and internal occipital crest. The length and the distance between each of the falces were measured. The mean length of the right falces cerebelli was 38 mm and the left was 41 mm. The mean distance between these two falces was 20 mm. No marginal sinus was detected. Each of the falces cerebelli had distinct base and apex and possessed a distinct occipital venous sinus on each attached border. These sinuses were noted to drain into the left and right transverse sinus respectively. After detaching the dura mater from inner bony surface of the occipital bone, it was noted that there were two distinct internal occipital crests arising and diverging inferiorly near the posterolateral borders of foramen magnum. The brain from these cadavers appeared grossly normal with no defect of the vermis. Neurosurgeons and neuroradiologists should be aware of such variations, as these could be potential sources of hemorrhage during suboccipital approaches or may lead to erroneous interpretations of imaging of the posterior cranial fossa.
    [Show full text]
  • 417.Full.Pdf
    Postgrad Med J: first published as 10.1136/pgmj.38.441.417 on 1 July 1962. Downloaded from POSTGRAD. MED. J. (I962), 38, 4I7 THE SO-CALLED GENERAL SYMPTOMS OF INCREASED INTRACRANIAL PRESSURE Clinico-pathological Report Based on a Study of 100 Cases FATHY W. TADROS, PH.D., M.R.C.P.(Edin.), D.P.M. 0. H. SEROUR, M.CH. S. A. ZAKI, M.D., B.Sc. RASHAD SAKR, M.D., D.CH. From the Faculty of Medicine, Cairo University THERE has been much controversy regarding the in the cerebellum, brain stem and around the pathogenesis of the so-called general symptoms of aqueduct and 22 in the cerebrum; I2 cases were brain tumours. They are often ascribed to one or meningiomas, nine parasagittal, one in the lateral more factors which produce an increase in the sphenoid ridge, one suprasellar and one infra- intracranial pressure. It is generally accepted that tentorial in the pineal region. The rest comprised these factors are: firstly, the increase in the IO tuberculomas, eight cerebellar and two hemi- contents of the intracranial cavity produced by spherical; four pinealomas; two neurinomas; the size of the tumour and the surrounding cedema; two choroid carcinomas; one cranio-pharyngioma; secondly, the effect on the vascular system, one cholesteatoma; four hamangioblastoma cere- producing rise in the venous pressure; and, belli and two chronic abscesses, one cerebellar and thirdly, the effect on the flow of the cerebrospinal one temporal. fluid. In each case serial coronal sections of the braincopyright. The present work is devoted to the study of were made and the extent of the lesion verified.
    [Show full text]
  • Tumors of the Meninges and Related Tissues: Meningiomas and Sarcomas
    CHAPTER 30 Tumors of the Meninges and Related Tissues: Meningiomas and Sarcomas Kimberly P. Cockerham, John S. Kennerdell, Joseph C. Maroon, and Ghassan K. Bejjani ANATOMY OFTHE MENINGES Associations Dura Mater Diagnosis Arachnoid Treatment Pia Mater Adjuvant Therapy MENINGIOMAS Clinical Characteristics by Location Histogenesis SARCOMAS OFTHE MENINGES AND BRAIN Incidence Chondrosarcoma Pathology Osteogenic Sarcoma Cytogenetics Primary Sarcoma of the Meninges and Brain Endocrinology Rhabdomyosarcoma ANATOMY OF THE MENINGES The meninges of the brain and spinal cord consist of three into several freely communicating compartments. They in- different layers: the dura mater, arachnoid (tela arach- clude the falx cerebri, the tentorium cerebelli, the falx cere- noidea), and pia mater. Considerable anatomic differences belli, and the diaphragma sellae. exist among these structures, and these differences influence The falx cerebri, so named because of its sickle-like form, the nature, location, and spread of tumors that arise from is a fixed, arched process that descends vertically in the them. longitudinal fissure between the cerebral hemispheres (Fig. 30.2). The tentorium cerebelli is an arched lamina that is DURA MATER elevated in its midportion and inclines downward toward its peripheral attachments on both sides. It covers the superior The dura mater, typically referred to as the dura, is a thick surface of the cerebellum and supports the occipital lobes membrane that is adjacent to the inner table of the skull and (Fig. 30.2). The falx cerebelli is a small triangular process acts both as the functional periosteum of the skull and the of dura mater that lies beneath the tentorium cerebelli in outermost membrane of the brain (Fig.
    [Show full text]
  • A Study of Unusual Presentations at the Internal Occipital Protuberance
    Original Research Article A study of unusual presentations at the internal occipital protuberance Sudeepa Das¹, Gyanraj Singh2, Satya Narayan Shamal3, Bikash Chandra Satapathy4* 1,2Assistant Professor, 3Professor, Department of Anatomy, KIMS, Bhubaneswar, Odisha. 4Assistant Professor, Department of Anatomy, AIIMS Mangalagiri, Andhra Pradesh, INDIA. Email: [email protected] Abstract The dural venous sinuses contains the venous blood originating from most parts of the cranial cavity. In this study forty head and neck specimens with intact dural folds were studied over 3 years period. In 2 cases variation was noted at the internal occipital protuberance during the routine dissection in Anatomy department. After separating the dura mater from the occipital bone, two distinct internal occipital crests were apparent which then diverge near the foramen magnum. We encountered duplicated internal Occipital crest along with duplicated falx cerebelli and occipital sinus. Of both specimens the falces and the distance between them were recorded. Each of the falx cerebelli had an apex and base with a marked occipital venous sinus attached to its border. These sinuses were draining into their respective transverse sinuses. In both the cases there was wide posterior cerebellar notch and foramen of Magendie associated with large cisterna magna. There was neither any marginal sinus detected nor any defect was marked in the vermis. Knowledge of this variation of posterior cranial fossa would be helpful in suboccipital approaches. Key Words: Variation,
    [Show full text]
  • Title: an Assessment of the Role of the Falx Cerebri and Tentorium Cerebelli in the Cranium of the Cat (Felis Silvestris Catus)
    1 Title: An assessment of the role of the falx cerebri and tentorium cerebelli in the 2 cranium of the cat (Felis silvestris catus) 3 4 Víctor Sellés de Lucas 1, Hugo Dutel 1, Susan E. Evans 2, Flora Gröning 3, Alana C. 5 Sharp 2, Peter J. Watson 1, Michael J. Fagan 1 6 1 School of Engineering and Computer Science, Medical and Biological Engineering 7 Research Group, University of Hull, Hull HU6 7RX, UK 8 2 Department of Cell and Developmental Biology, University College London, London 9 WCIE 6BT, UK 10 3 School of Medicine, Medical Sciences and Nutrition, University of Aberdeen, 11 Aberdeen AB25 2ZD, UK 12 13 Corresponding author email address: [email protected] 14 15 16 17 18 19 20 21 22 23 24 25 26 27 Abstract: The falx cerebri and the tentorium cerebelli are two projections of the dura 28 mater in the cranial cavity which ossify to varying degrees in some mammalian species. 29 The idea that the ossification of these structures may be necessary to support the loads 30 arising during feeding has been proposed and dismissed in the past, but never tested 31 quantitatively. To address this, a biomechanical model of a domestic cat (Felis silvestris 32 catus) skull was created and the material properties of the falx and tentorium were 33 varied for a series of loading regimes incorporating the main masticatory and neck 34 muscles during biting. Under these loading conditions, ossification of the falx cerebri 35 does not have a significant impact on the stress in the cranial bones.
    [Show full text]
  • Investigating the Mechanical and Structural Properties of the Superior Sagittal Sinus
    IRC-20-64 IRCOBI conference 2020 Investigating the Mechanical and Structural Properties of the Superior Sagittal Sinus Darragh R. Walsh, Aisling M. Ross, David T. Newport, John J. E. Mulvihill Abstract The meninges, which are a composite tissue surrounding the brain, play an important role in the mechanopathology of traumatic brain injury. Studies have demonstrated that the meninges are pivotal in mitigating the damaging strains placed on the cortex from both physiological and pathophysiological head movement, which can occur during dynamic events such as traffic accidents. Conversely, structures such as the falx and tentorium have been shown to induce large deleterious strains within the brain. Understanding the mechanical behaviour of these tissues is important to predict computational model brain strains. This study provides the first biomechanical and structural evaluation of the structures anatomically tethered to the falx cerebri, the superior sagittal sinus. We utilise uniaxial tensile testing, digital image correlation analysis and scanning electron microscopy on porcine superior sagittal sinus tissue to show that these structures are mechanically stiffer (with elastic moduli ranging from 33 to 58 MPa) than the properties that are typically assigned to them in computational models of traumatic brain injury (elastic modulus of 31.5 MPa). This work has the potential to improve the biofidelity of traumatic brain injury finite element models, thus improving crash reconstruction and injury prediction efforts. Keywords Dura mater, finite element modelling, mechanical characterisation, TBI, venous sinuses. I. INTRODUCTION Traumatic brain injury (TBI) can be caused by rapid linear or rotational acceleration of the head experienced in vehicular collisions, explosions, falls, or assaults.
    [Show full text]
  • Meninges, Ventricles, and CSF
    Meninges, Ventricles, and CSF Lecture (19) ▪ Important ▪ Doctors Notes Please check our Editing File ▪ Notes/Extra explanation ه هذا العمل مب ين بشكل أسا يس عىل عمل دفعة 436 مع المراجعة { َوَم نْ يَ َت َو َ ّكْ عَ َلْ ا َّْلل فَهُ َوْ َحْ سْ ُ ُُْ} والتدقيق وإضافة المﻻحظات وﻻ يغ ين عن المصدر اﻷسا يس للمذاكرة ▪ Objectives At the end of the lecture, students should be able to: ✓ Explain the cerebral meninges & compare between the main dural folds. ✓ Identify the spinal meninges & locate the level of the termination of each of them. ✓ Describe the importance of the subarachnoid space. ✓ Explain the ventricular system of the CNS and locate the site of each of them. ✓ Analyze the formation, circulation, drainage, and functions of the CSF. ✓ Justify the clinical point related to the CSF. Meninges 02:02 The brain and spinal cord (CNS) are invested by three concentric membranes/ layers: 1-The outermost layer is the dura matter.(fibrous) Dura Outside 2-The middle layer is the arachnoid matter.(translucent) Pia Inside 3-The innermost layer is the pia matter.(translucent) 1- (The dura surround 2- (from which it is 3- (Pia mater is a the brain and the separated by thin fibrous tissue that spinal cord and is the subarachnoid space . is impermeable to fluid. responsible for The delicate arachnoid layer This allows the pia keeping in the CSF) is attached to the inside of mater to enclose csf) the dur and surrounds the brain and spinal cord.) Meninges 1- Dura Matter o The cranial dura is a two layered tough, fibrous, thick membrane that surrounds the brain.
    [Show full text]
  • Falx Cerebri Giant Chondroma ‒ Case Report
    logy & N ro eu u r e o N p h f y o s Journal of Neurology & l i a o l n o r g Radoi et al., J Neurol Neurophysiol 2017, 8:4 u y o J Neurophysiology DOI: 10.4172/2155-9562.1000433 ISSN: 2155-9562 Case Report Open Access Falx Cerebri Giant Chondroma ‒ Case Report Mugurel Petrinel Radoi*, Ram Vakilnejad, Lidia Gheorghitescu and Florin Stefanescu National Institute of Neurology and Neurovascular Diseases-Bucharest, Neurosurgical Department, Romania *Corresponding author: Mugurel Petrinel Radoi, National Institute of Neurology and Neurovascular Diseases-Bucharest, Neurosurgical Department, Romania, Tel: 40723527292; E-mail: [email protected] Received date: October 06, 2016; Accepted date: July 05, 2017; Published date: July 10, 2017 Copyright: © 2017 Radoi MP, et al. 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 Intracranial chondromas are rare skull base tumors, but those arising from the falx cerebri are extremely rare. Of our knowledge, there have been reported no more than seventeen cases. Surgical gross removal of falx chondroma is associated with good outcome. We bring into focus the case of a large falcine chondroma and discuss its diagnosis, surgical management and prognosis. Keywords: Brain tumor; Giant chondroma; Falx cerebri; Surgery Introduction Chondromas are infrequent brain tumors, with a very low incidence, estimated at 0.2-0.5% of all intracerebral tumors [1,2].The skull base synchondrosis represents the usual origin of chondromas [3],but, exceptionally, they develop from the convexital dura mater or the falx [4,5].
    [Show full text]
  • A Peculiar Case of Dural Venous Sinuses with Resulting Atypical Bony Markings in Posterior Cranial Fossa
    International Journal of Research in Medical Sciences Khorwal G et al. Int J Res Med Sci. 2017 Jun;5(6):2830-2832 www.msjonline.org pISSN 2320-6071 | eISSN 2320-6012 DOI: http://dx.doi.org/10.18203/2320-6012.ijrms20172500 Case Report A peculiar case of dural venous sinuses with resulting atypical bony markings in posterior cranial fossa Gitanjali Khorwal*, Sunita Kalra Department of Anatomy, University College of Medical Sciences, Delhi, India Received: 20 March 2017 Accepted: 19 April 2017 *Correspondence: Dr. Gitanjali Khorwal, E-mail: [email protected] Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. ABSTRACT A paramedian or midline suboccipital approach for craniotomies and craniectomies is commonly employed for decompression or tumour resections from posterior cranial fossa. The reference for midline is taken as the line joining the nasion and inion on the surface of the skull which is the estimated position of superior sagittal sinus. In the interior, the internal occipital protuberance is the site of confluence of sinuses which presents a spectrum of variations. An unusual pattern of drainage of dural venous sinuses was observed at the site of customary confluence during routine dissection of head region for undergraduate medical students in a sixty-year-old female cadaver. The superior sagittal sinus continued as right transverse sinus as usual but it was connected to the left transverse sinus through a venous channel.
    [Show full text]
  • Lecture 4 Human Anatomy Second Stage احمد جسام النقيب د. the Meninges the Brain in the Skull Is Surro
    Lecture 4 Human Anatomy second stage د. احمد جسام النقيب The Meninges The brain in the skull is surrounded by three protective membranes, or meninges: the dura mater, the arachnoid mater, and the pia mater. (The spinal cord in the vertebral column is also surrounded by three meninges) Dura Mater of the Brain The dura mater is conventionally described as two layers: the endosteal layer and the meningeal layer. These are closely united except along certain lines, where they separate to form venous sinuses. The endosteal layer is nothing more than the ordinary periosteum covering the inner surface of the skull bones. It does not extend through the foramen magnum to become continuous with the dura mater of the spinal cord. Around the margins of all the foramina in the skull, it becomes continuous with the periosteum on the outside of the skull bones. At the sutures, it is continuous with the sutural ligaments. It is most strongly adherent to the bones over the base of the skull. The meningeal layer is the dura mater proper. It is a dense, strong, fibrous membrane covering the brain and is continuous through the foramen magnum with the dura mater of the spinal cord. It provides tubular sheaths for the cranial nerves as the latter pass through the foramina in the skull. Outside the skull, the sheaths fuse with the epineurium of the nerves. The meningeal layer sends inward four septa that divide the cranial cavity into freely communicating spaces lodging the subdivisions of the brain. The function of these septa is to restrict the rotatory displacement of the brain.
    [Show full text]