1
|
Abstract
This article discusses new diffusion-weighted imaging (DWI) sequences, diffusion tensor imaging (DTI), and fiber tractography (FT), as well as more advanced diffusion imaging in pediatric brain and spine. Underlying disorder and pathophysiology causing diffusion abnormalities are discussed. Multishot echo planar imaging (EPI) DWI and non-EPI DWI provide higher spatial resolution with less susceptibility artifact and distortion, which are replacing conventional single-shot EPI DWI. DTI and FT have established clinical significance in pediatric brain and spine. This article discusses advanced diffusion imaging, including diffusion kurtosis imaging, neurite orientation dispersion and density imaging, diffusion spectrum imaging, intravoxel incoherent motion, and oscillating-gradient spin-echo.
Collapse
Affiliation(s)
- Toshio Moritani
- Division of Neuroradiology, Department of Radiology, University of Michigan, 1500 East Medical Center Drive, UH B2 A209K, Ann Arbor, MI 48109, USA.
| |
Collapse
|
2
|
Accogli A, Geraldo AF, Piccolo G, Riva A, Scala M, Balagura G, Salpietro V, Madia F, Maghnie M, Zara F, Striano P, Tortora D, Severino M, Capra V. Diagnostic Approach to Macrocephaly in Children. Front Pediatr 2021; 9:794069. [PMID: 35096710 PMCID: PMC8795981 DOI: 10.3389/fped.2021.794069] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/02/2021] [Indexed: 01/19/2023] Open
Abstract
Macrocephaly affects up to 5% of the pediatric population and is defined as an abnormally large head with an occipitofrontal circumference (OFC) >2 standard deviations (SD) above the mean for a given age and sex. Taking into account that about 2-3% of the healthy population has an OFC between 2 and 3 SD, macrocephaly is considered as "clinically relevant" when OFC is above 3 SD. This implies the urgent need for a diagnostic workflow to use in the clinical setting to dissect the several causes of increased OFC, from the benign form of familial macrocephaly and the Benign enlargement of subarachnoid spaces (BESS) to many pathological conditions, including genetic disorders. Moreover, macrocephaly should be differentiated by megalencephaly (MEG), which refers exclusively to brain overgrowth, exceeding twice the SD (3SD-"clinically relevant" megalencephaly). While macrocephaly can be isolated and benign or may be the first indication of an underlying congenital, genetic, or acquired disorder, megalencephaly is most likely due to a genetic cause. Apart from the head size evaluation, a detailed family and personal history, neuroimaging, and a careful clinical evaluation are crucial to reach the correct diagnosis. In this review, we seek to underline the clinical aspects of macrocephaly and megalencephaly, emphasizing the main differential diagnosis with a major focus on common genetic disorders. We thus provide a clinico-radiological algorithm to guide pediatricians in the assessment of children with macrocephaly.
Collapse
Affiliation(s)
- Andrea Accogli
- Division of Medical Genetics, Department of Medicine, McGill University Health Centre, Montreal, QC, Canada
| | - Ana Filipa Geraldo
- Diagnostic Neuroradiology Unit, Imaging Department, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - Gianluca Piccolo
- Pediatric Neurology and Neuromuscular Diseases Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Antonella Riva
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy
| | - Marcello Scala
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy
| | - Ganna Balagura
- Pediatric Neurology and Neuromuscular Diseases Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Vincenzo Salpietro
- Pediatric Neurology and Neuromuscular Diseases Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy
| | - Francesca Madia
- Pediatric Clinic and Endocrinology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Mohamad Maghnie
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy.,Pediatric Clinic and Endocrinology, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Federico Zara
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy.,Medical Genetics Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| | - Pasquale Striano
- Pediatric Neurology and Neuromuscular Diseases Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, Genoa, Italy
| | - Domenico Tortora
- Neuroradiology Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | | | - Valeria Capra
- Medical Genetics Unit, IRCCS Giannina Gaslini Institute, Genoa, Italy
| |
Collapse
|
3
|
Severino M, Geraldo AF, Utz N, Tortora D, Pogledic I, Klonowski W, Triulzi F, Arrigoni F, Mankad K, Leventer RJ, Mancini GMS, Barkovich JA, Lequin MH, Rossi A. Definitions and classification of malformations of cortical development: practical guidelines. Brain 2020; 143:2874-2894. [PMID: 32779696 PMCID: PMC7586092 DOI: 10.1093/brain/awaa174] [Citation(s) in RCA: 120] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 03/14/2020] [Accepted: 03/30/2020] [Indexed: 12/31/2022] Open
Abstract
Malformations of cortical development are a group of rare disorders commonly manifesting with developmental delay, cerebral palsy or seizures. The neurological outcome is extremely variable depending on the type, extent and severity of the malformation and the involved genetic pathways of brain development. Neuroimaging plays an essential role in the diagnosis of these malformations, but several issues regarding malformations of cortical development definitions and classification remain unclear. The purpose of this consensus statement is to provide standardized malformations of cortical development terminology and classification for neuroradiological pattern interpretation. A committee of international experts in paediatric neuroradiology prepared systematic literature reviews and formulated neuroimaging recommendations in collaboration with geneticists, paediatric neurologists and pathologists during consensus meetings in the context of the European Network Neuro-MIG initiative on Brain Malformations (https://www.neuro-mig.org/). Malformations of cortical development neuroimaging features and practical recommendations are provided to aid both expert and non-expert radiologists and neurologists who may encounter patients with malformations of cortical development in their practice, with the aim of improving malformations of cortical development diagnosis and imaging interpretation worldwide.
Collapse
Affiliation(s)
| | - Ana Filipa Geraldo
- Neuroradiology Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
- Neuroradiology Unit, Imaging Department, Centro Hospitalar Vila Nova de Gaia/Espinho (CHVNG/E), Vila Nova de Gaia, Portugal
| | - Norbert Utz
- Department of Pediatric Radiology, HELIOS Klinikum Krefeld, Germany
| | - Domenico Tortora
- Neuroradiology Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Ivana Pogledic
- Division of Neuroradiology and Musculoskeletal Radiology, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Wlodzimierz Klonowski
- Nalecz Institute of Biocybernetics and Biomedical Engineering Polish Academy of Sciences, Poland
| | - Fabio Triulzi
- Neuroradiology Unit, Fondazione IRCCS Cà Granda, Ospedale Maggiore Policlinico, Department of Pathophysiology and Transplantation, Università degli Studi Milano, Italy
| | - Filippo Arrigoni
- Department of Neuroimaging Lab, Scientific Institute, IRCCS E. Medea, Bosisio Parini, Italy
| | - Kshitij Mankad
- Department of Radiology, Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London, UK
| | - Richard J Leventer
- Department of Neurology Royal Children’s Hospital, Murdoch Children’s Research Institute and University of Melbourne Department of Pediatrics, Melbourne, Australia
| | - Grazia M S Mancini
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - James A Barkovich
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, CA, USA
- Department of Neurology, University of California, San Francisco, CA, USA
| | - Maarten H Lequin
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Andrea Rossi
- Neuroradiology Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| |
Collapse
|
4
|
Jeon TY, Poliakov AV, Friedman SD, Bozarth XL, Novotny EJ, Hauptman JS, Moon SH, Shaw DWW. Structural MRI and tract-based spatial statistical analysis of diffusion tensor imaging in children with hemimegalencephaly. Neuroradiology 2020; 62:1467-1474. [PMID: 32651620 DOI: 10.1007/s00234-020-02491-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 07/05/2020] [Indexed: 10/23/2022]
Abstract
PURPOSE To investigate the gross white matter abnormalities in the structural brain MR imaging as well as white matter microstructural alterations using tract-based spatial statistics (TBSS) analysis of diffusion tensor imaging (DTI) in both affected and contralateral cerebral hemispheres of children with hemimegalencephaly (HMEG). METHODS From 2003 to 2019, we retrospectively reviewed brain MR images in 20 children (11 boys, 2 days-16.5 years) with HMEG, focusing on gross white matter abnormalities. DTI was evaluated in 12 patients (8 boys, 3 months-16.5 years) with HMEG and 12 age-, sex-, and magnetic field strength-matched control subjects. TBSS analysis was performed to analyze main white matter tracts. Regions of significant differences in fractional anisotropy (FA) were determined between HMEG and control subjects and between affected and contralateral hemispheres of HMEG. RESULTS Gross white matter abnormalities were noted in both affected (n = 20, 100%) and contralateral hemisphere (n = 4, 20%) of HMEG. FA values were significantly decreased in both hemispheres of HMEG, compared with control subjects (P < 0.05). Contralateral hemispheres of HMEG showed regions with significantly decreased FA values compared with affected hemispheres (P < 0.05). CONCLUSIONS In addition to gross white matter abnormalities particularly evident in affected hemispheres, DTI analysis detected widespread microstructural alterations in both affected and contralateral hemispheres in HMEG suggesting HMEG may involve broader abnormalities in neuronal networks.
Collapse
Affiliation(s)
- Tae Yeon Jeon
- Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul, Republic of Korea.
| | - Andrew V Poliakov
- Department of Radiology, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Seth D Friedman
- Department of Radiology, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Xiuhua L Bozarth
- Department of Neurology, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Edward J Novotny
- Department of Neurology, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Jason S Hauptman
- Department of Neurological Surgery, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Sung-Hoon Moon
- Department of Internal Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Republic of Korea
| | - Dennis W W Shaw
- Department of Radiology, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| |
Collapse
|
5
|
Imaging the Patient with Epilepsy. ACTA ACUST UNITED AC 2020. [DOI: 10.1007/978-3-030-38490-6_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
6
|
Enokizono M, Sato N, Ota M, Shigemoto Y, Morimoto E, Oba M, Sone D, Kimura Y, Sugai K, Sasaki M, Ikegaya N, Iwasaki M, Matsuda H. Disrupted cortico-ponto-cerebellar pathway in patients with hemimegalencephaly. Brain Dev 2019; 41:507-515. [PMID: 30665821 DOI: 10.1016/j.braindev.2019.01.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 12/07/2018] [Accepted: 01/04/2019] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Cerebellar dysmaturation and injury is associated with a wide range of neuromotor, neurocognitive and behavioral disorders as well as with preterm birth. We used diffusion tensor MR imaging to investigate a disruption in structural cortico-ponto-cerebellar (CPC) connectivity in children with infantile-onset severe epilepsy. METHODS We performed CPC tract reconstructions in 24 hemimegalencephaly (HME) patients, 28 West syndrome (WS) of unknown etiology patients, and 25 pediatric disease control subjects without a history of epilepsy nor brain abnormality on MRI. To identify the CPC tract, we placed a seeding ROI separately in each right and left cerebral peduncle. We evaluated the distribution patterns of the CPC tracts to the cerebellum and their correlation with clinical findings. RESULTS In control and WS of unknown etiology groups, both sides' CPC tracts descended to bilateral hemispheres in 20 (80.0%) and 21 (75.0%); mixed (bilateral on one side and unilateral on the other side) in five (20.0%) and five (17.9%); and unilateral in zero (0.0%) and two (7.1%), respectively. However, in the HME, both sides' CPC tracts descended to bilateral hemispheres in four (16.7%); mixed in 13 (54.1%); and unilateral in seven (29.2%). These CPC patterns differed significantly between the HME and other groups (p < 0.001). Among HME patients, those with a unilateral cerebellar distribution on both sides had significantly earlier seizure onset (p = 0.049) and more frequent seizures (p = 0.052) at a trend level compared to those with bilateral and mixed distributions. CONCLUSION Disrupted CPC tracts were observed more frequently in HME patients than in WS of unknown etiology patients and controls, and they may be correlated with earlier seizure onset and more frequent seizures in HME patients. DTI is a useful and non-invasive method for speculating the pathology in the developing brain.
Collapse
Affiliation(s)
- Mikako Enokizono
- Department of Radiology, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan
| | - Noriko Sato
- Department of Radiology, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan.
| | - Miho Ota
- Integrative Brain Imaging Center, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan; Department of Mental Disorder Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Yoko Shigemoto
- Department of Radiology, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan; Integrative Brain Imaging Center, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan
| | - Emiko Morimoto
- Department of Radiology, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan
| | - Masatoshi Oba
- Department of Orthopedics, Yokohama City Municipal Hospital, Yokohama, Japan
| | - Daichi Sone
- Integrative Brain Imaging Center, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan
| | - Yukio Kimura
- Department of Radiology, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan
| | - Kenji Sugai
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Masayuki Sasaki
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Naoki Ikegaya
- Department of Neurosurgery, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Masaki Iwasaki
- Department of Neurosurgery, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Hiroshi Matsuda
- Integrative Brain Imaging Center, National Center Hospital of Neurology and Psychiatry, Tokyo, Japan
| |
Collapse
|
7
|
Meoded A, Huisman TAGM. Diffusion Tensor Imaging of Brain Malformations: Exploring the Internal Architecture. Neuroimaging Clin N Am 2019; 29:423-434. [PMID: 31256863 DOI: 10.1016/j.nic.2019.03.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Diffusion tensor imaging (DTI) is an advanced MR imaging technique that provides noninvasive qualitative and quantitative information about the white matter microarchitecture. By measuring the three-dimensional directional characteristics of water molecule diffusion/mobility, DTI generates unique tissue contrasts that are used to study the axonal organization of the central nervous system. Its applications include quantitative evaluation of the brain connectivity, development, and white matter diseases. This article reviews DTI and fiber tractography findings in several brain malformations and highlights the added value of DTI and fiber tractography compared with conventional MR imaging.
Collapse
Affiliation(s)
- Avner Meoded
- Johns Hopkins All Children's Hospital, 501 6th Avenue South, St Petersburg, FL 33701, USA.
| | - Thierry A G M Huisman
- Edward B. Singleton Department of Radiology, Texas Children's Hospital, 6701 Fannin Street, Suite 470, Houston, TX 77030, USA
| |
Collapse
|
8
|
Pringsheim M, Mitter D, Schröder S, Warthemann R, Plümacher K, Kluger G, Baethmann M, Bast T, Braun S, Büttel HM, Conover E, Courage C, Datta AN, Eger A, Grebe TA, Hasse-Wittmer A, Heruth M, Höft K, Kaindl AM, Karch S, Kautzky T, Korenke GC, Kruse B, Lutz RE, Omran H, Patzer S, Philippi H, Ramsey K, Rating T, Rieß A, Schimmel M, Westman R, Zech FM, Zirn B, Ulmke PA, Sokpor G, Tuoc T, Leha A, Staudt M, Brockmann K. Structural brain anomalies in patients with FOXG1 syndrome and in Foxg1+/- mice. Ann Clin Transl Neurol 2019; 6:655-668. [PMID: 31019990 PMCID: PMC6469254 DOI: 10.1002/acn3.735] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 01/22/2019] [Indexed: 01/11/2023] Open
Abstract
Objective FOXG1 syndrome is a rare neurodevelopmental disorder associated with heterozygous FOXG1 variants or chromosomal microaberrations in 14q12. The study aimed at assessing the scope of structural cerebral anomalies revealed by neuroimaging to delineate the genotype and neuroimaging phenotype associations. Methods We compiled 34 patients with a heterozygous (likely) pathogenic FOXG1 variant. Qualitative assessment of cerebral anomalies was performed by standardized re-analysis of all 34 MRI data sets. Statistical analysis of genetic, clinical and neuroimaging data were performed. We quantified clinical and neuroimaging phenotypes using severity scores. Telencephalic phenotypes of adult Foxg1+/- mice were examined using immunohistological stainings followed by quantitative evaluation of structural anomalies. Results Characteristic neuroimaging features included corpus callosum anomalies (82%), thickening of the fornix (74%), simplified gyral pattern (56%), enlargement of inner CSF spaces (44%), hypoplasia of basal ganglia (38%), and hypoplasia of frontal lobes (29%). We observed a marked, filiform thinning of the rostrum as recurrent highly typical pattern of corpus callosum anomaly in combination with distinct thickening of the fornix as a characteristic feature. Thickening of the fornices was not reported previously in FOXG1 syndrome. Simplified gyral pattern occurred significantly more frequently in patients with early truncating variants. Higher clinical severity scores were significantly associated with higher neuroimaging severity scores. Modeling of Foxg1 heterozygosity in mouse brain recapitulated the associated abnormal cerebral morphology phenotypes, including the striking enlargement of the fornix. Interpretation Combination of specific corpus callosum anomalies with simplified gyral pattern and hyperplasia of the fornices is highly characteristic for FOXG1 syndrome.
Collapse
Affiliation(s)
- Milka Pringsheim
- Klinik für Neuropädiatrie und Neurologische Rehabilitation Epilepsiezentrum für Kinder und Jugendliche Schön Klinik Vogtareuth Vogtareuth Germany.,Research Institute "Rehabilitation, Transition, Rehabilitation" Paracelsus Medical University Salzburg Austria
| | - Diana Mitter
- Institute of Human Genetics University of Leipzig Medical Center Leipzig Germany
| | - Simone Schröder
- Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders University Medical Center Göttingen Göttingen Germany
| | - Rita Warthemann
- Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders University Medical Center Göttingen Göttingen Germany
| | - Kim Plümacher
- Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders University Medical Center Göttingen Göttingen Germany
| | - Gerhard Kluger
- Klinik für Neuropädiatrie und Neurologische Rehabilitation Epilepsiezentrum für Kinder und Jugendliche Schön Klinik Vogtareuth Vogtareuth Germany.,Research Institute "Rehabilitation, Transition, Rehabilitation" Paracelsus Medical University Salzburg Austria
| | | | - Thomas Bast
- Epilepsiezentrum Kork Kehl-Kork Germany.,Medical Faculty University of Freiburg Freiburg Germany
| | - Sarah Braun
- Asklepios Children's Hospital St. Augustin Germany
| | | | - Elizabeth Conover
- Department of Genetic Medicine Munroe Meyer Institute University of Nebraska Medical Center Omaha Omaha Nebraska USA
| | - Carolina Courage
- Division of Human Genetics Department of Pediatrics, Inselspital University of Bern Bern Switzerland.,The Folkhälsan Institute of Genetics University of Helsinki Helsinki Finland
| | - Alexandre N Datta
- Department of Pediatric Neurology and Developmental Medicine University of Basel Children's Hospital Basel Switzerland
| | - Angelika Eger
- Sozialpädiatrisches Zentrum Leipzig (Frühe Hilfe Leipzig) Leipzig Germany
| | - Theresa A Grebe
- Division of Genetics and Metabolism Phoenix Children's Hospital Phoenix Arizona USA
| | | | - Marion Heruth
- Klinik für Kinder- und Jugendmedizin Sana Kliniken Leipziger Land Borna Germany
| | - Karen Höft
- Klinik für Kinder- und Jugendmedizin Klinikum Magdeburg gGmbH Magdeburg Germany
| | - Angela M Kaindl
- Klinik für Pädiatrie m.S. Neurologie Sozialpädiatrisches Zentrum Institut für Zell- und Neurobiologie Charité-Universitätsmedizin Berlin Berlin Germany
| | - Stephanie Karch
- Klinik für Kinder- und Jugendmedizin Sozialpädiatrisches Zentrum Universitätsklinikum Heidelberg Heidelberg Germany
| | | | - Georg C Korenke
- Klinik für Neuropädiatrie und angeborene Stoffwechselerkrankungen Elisabeth Kinderkrankenhaus Klinikum Oldenburg Germany
| | - Bernd Kruse
- Neuropediatric Department Helios-Klinikum Hildesheim Hildesheim Germany
| | - Richard E Lutz
- Department of Genetic Medicine Munroe Meyer Institute University of Nebraska Medical Center Omaha Omaha Nebraska USA
| | - Heymut Omran
- Department of General Pediatrics University Children's Hospital Muenster Muenster Germany
| | - Steffi Patzer
- Klinik für Kinder- und Jugendmedizin Krankenhaus St. Elisabeth und St. Barbara Halle/Saale Germany
| | - Heike Philippi
- Sozialpädiatrisches Zentrum Frankfurt Mitte Frankfurt am Main Germany
| | - Keri Ramsey
- Center for Rare Childhood Disorders Translational Genomics Research Institute Phoenix Arizona USA
| | - Tina Rating
- Sozialpädiatrisches Institut Klinikum Bremen-Mitte Bremen Germany
| | - Angelika Rieß
- Institut für Medizinische Genetik und angewandte Genomik Universitätsklinikum Tübingen Tübingen Germany
| | - Mareike Schimmel
- Children's Hospital Section of Neuropaediatrics Klinikum Augsburg Augsburg Germany
| | - Rachel Westman
- Children's Specialty Center St. Luke's Children's Hospital Boise Idaho USA
| | - Frank-Martin Zech
- Klinik für Kinder- und Jugendmedizin St. Vincenz-Krankenhaus Paderborn Paderborn Germany
| | - Birgit Zirn
- Genetic Counselling and Diagnostic, genetikum Stuttgart Stuttgart Germany
| | - Pauline A Ulmke
- Institute of Neuroanatomy University Medical Center Georg August University Göttingen Germany
| | - Godwin Sokpor
- Institute of Neuroanatomy University Medical Center Georg August University Göttingen Germany
| | - Tran Tuoc
- Institute of Neuroanatomy University Medical Center Georg August University Göttingen Germany
| | - Andreas Leha
- 'Core Facility Medical Biometry and Statistical Bioinformatics' Department of Medical Statistics University Medical Center Göttingen Göttingen Germany
| | - Martin Staudt
- Klinik für Neuropädiatrie und Neurologische Rehabilitation Epilepsiezentrum für Kinder und Jugendliche Schön Klinik Vogtareuth Vogtareuth Germany
| | - Knut Brockmann
- Interdisciplinary Pediatric Center for Children with Developmental Disabilities and Severe Chronic Disorders University Medical Center Göttingen Göttingen Germany
| |
Collapse
|
9
|
Shrot S, Hwang M, Stafstrom CE, Huisman TAGM, Soares BP. Dysplasia and overgrowth: magnetic resonance imaging of pediatric brain abnormalities secondary to alterations in the mechanistic target of rapamycin pathway. Neuroradiology 2017; 60:137-150. [PMID: 29279945 DOI: 10.1007/s00234-017-1961-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Accepted: 12/07/2017] [Indexed: 12/22/2022]
Abstract
The current classification of malformations of cortical development is based on the type of disrupted embryological process (cell proliferation, migration, or cortical organization/post-migrational development) and the resulting morphological anomalous pattern of findings. An ideal classification would include knowledge of biological pathways. It has recently been demonstrated that alterations affecting the mechanistic target of rapamycin (mTOR) signaling pathway result in diverse abnormalities such as dysplastic megalencephaly, hemimegalencephaly, ganglioglioma, dysplastic cerebellar gangliocytoma, focal cortical dysplasia type IIb, and brain lesions associated with tuberous sclerosis. We review the neuroimaging findings in brain abnormalities related to alterations in the mTOR pathway, following the emerging trend from morphology towards genetics in the classification of malformations of cortical development. This approach improves the understanding of anomalous brain development and allows precise diagnosis and potentially targeted therapies that may regulate mTOR pathway function.
Collapse
Affiliation(s)
- Shai Shrot
- Division of Pediatric Radiology and Pediatric Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 1800 Orleans Street, Zayed 4174, Baltimore, MD, 21287, USA
- Department of Diagnostic Imaging, Sheba Medical Center, 52621, Ramat-Gan, Israel
| | - Misun Hwang
- Division of Pediatric Radiology and Pediatric Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 1800 Orleans Street, Zayed 4174, Baltimore, MD, 21287, USA
| | - Carl E Stafstrom
- Division of Pediatric Neurology, Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21287, USA
| | - Thierry A G M Huisman
- Division of Pediatric Radiology and Pediatric Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 1800 Orleans Street, Zayed 4174, Baltimore, MD, 21287, USA
| | - Bruno P Soares
- Division of Pediatric Radiology and Pediatric Neuroradiology, Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 1800 Orleans Street, Zayed 4174, Baltimore, MD, 21287, USA.
| |
Collapse
|
10
|
Abstract
We aim to review the magnetic resonance imaging appearance of malformations of midbrain and hindbrain. These can be classified as predominantly cerebellar malformations, combined cerebellar and brain stem malformations, and predominantly brain stem malformations. The diagnostic criteria for the majority of these morphological malformations are based on neuroimaging findings. The predominantly cerebellar malformations include predominantly vermian hypoplasia seen in Dandy-Walker malformation and rhombencephalosynapsis, global cerebellar hypoplasia reported in lissencephaly and microlissencephaly, and unilateral cerebellar hypoplasia seen in PHACES, vanishing cerebellum, and cerebellar cleft. Cerebellar dysplasias are seen in Chudley-McCullough syndrome, associated with LAMA1 mutations and GPR56 mutations; Lhermitte-Duclos disease; and focal cerebellar dysplasias. Cerebellar hyperplasias are seen in megalencephaly-related syndromes and hemimegalencephaly with ipsilateral cerebellomegaly. Cerebellar and brain stem malformations include tubulinopathies, Joubert syndrome, cobblestone malformations, pontocerebellar hypoplasias, and congenital disorders of glycosylation type Ia. Predominantly brain stem malformations include congenital innervation dysgenesis syndrome, pontine tegmental cap dysplasia, diencephalic-mesencephalic junction dysplasia, disconnection syndrome, and pontine clefts.
Collapse
|
11
|
Oikawa T, Tatewaki Y, Murata T, Kato Y, Mugikura S, Takase K, Takahashi S. Utility of diffusion tensor imaging parameters for diagnosis of hemimegalencephaly. Neuroradiol J 2015; 28:628-33. [PMID: 26481187 DOI: 10.1177/1971400915609334] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND Hemimegalencephaly is a rare hamartomatous entity characterised by enlargement of all or part of the cerebral hemisphere ipsilaterally with cortical dysgenesis, large lateral ventricle and white matter hypertrophy with or without advanced myelination. Although conventional magnetic resonance imaging (MRI) is useful for detecting these diagnostic features, hemimegalencephaly is not always easily distinguished from other entities, especially when hemimegalencephaly shows blurring between the grey and white matter. Diffusion tensor imaging (DTI) is a functional MRI technique commonly used to assess the integrity of white matter. The usefulness of DTI in assessing hemimegalencephaly has not been fully elucidated. In this study, we clarified the characteristics of hemimegalencephaly with regard to DTI and its parameters including fractional anisotropy and apparent diffusion coefficient. METHODS Three patients with hemimegalencephaly underwent MRI including DTI. We first visually compared fractional anisotropy mapping and conventional MRI. Next, we quantitatively measured the fractional anisotropy and apparent diffusion coefficient values in the subcortical white matter of the hemisphere with hemimegalencephaly and corresponding normal-appearing contralateral regions and analysed the values using the Mann-Whitney U test. RESULTS On fractional anisotropy mapping, we could clearly distinguish the junction of grey and white matter and observed thicker white matter in the hemisphere with hemimegalencephaly, which was unclear on conventional MRI. The white matter in the hemisphere with hemimegalencephaly showed significantly higher fractional anisotropy (P<0.0001) and lower apparent diffusion coefficient (P=0.0022) values than the normal contralateral side. CONCLUSION DTI parameters showed salient hemimegalencephaly features and could be useful in its assessment.
Collapse
Affiliation(s)
- Tomomi Oikawa
- Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Japan
| | - Yasuko Tatewaki
- Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Japan
| | - Takaki Murata
- Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Japan
| | - Yumiko Kato
- Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Japan
| | - Shunji Mugikura
- Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Japan
| | - Kei Takase
- Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Japan
| | - Shoki Takahashi
- Department of Diagnostic Radiology, Tohoku University Graduate School of Medicine, Japan
| |
Collapse
|
12
|
Update on neuroimaging phenotypes of mid-hindbrain malformations. Neuroradiology 2014; 57:113-38. [DOI: 10.1007/s00234-014-1431-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 09/04/2014] [Indexed: 12/11/2022]
|
13
|
Kamiya K, Sato N, Saito Y, Nakata Y, Ito K, Shigemoto Y, Ota M, Sasaki M, Ohtomo K. Accelerated myelination along fiber tracts in patients with hemimegalencephaly. J Neuroradiol 2014; 41:202-10. [DOI: 10.1016/j.neurad.2013.08.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 08/26/2013] [Accepted: 08/29/2013] [Indexed: 10/26/2022]
|
14
|
Poretti A, Meoded A, Rossi A, Raybaud C, Huisman TAGM. Diffusion tensor imaging and fiber tractography in brain malformations. Pediatr Radiol 2013; 43:28-54. [PMID: 23288476 DOI: 10.1007/s00247-012-2428-9] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 04/09/2012] [Indexed: 01/19/2023]
Abstract
Diffusion tensor imaging (DTI) is an advanced MR technique that provides qualitative and quantitative information about the micro-architecture of white matter. DTI and its post-processing tool fiber tractography (FT) have been increasingly used in the last decade to investigate the microstructural neuroarchitecture of brain malformations. This article aims to review the use of DTI and FT in the evaluation of a variety of common, well-described brain malformations, in particular by pointing out the additional information that DTI and FT renders compared with conventional MR sequences. In addition, the relevant existing literature is summarized.
Collapse
Affiliation(s)
- Andrea Poretti
- Division of Pediatric Radiology, The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 600 N. Wolfe St., Nelson Basement, B-173, Baltimore, MD 21287-0842, USA
| | | | | | | | | |
Collapse
|
15
|
Development and dysgenesis of the cerebral cortex: malformations of cortical development. Neuroimaging Clin N Am 2012; 21:483-543, vii. [PMID: 21807310 DOI: 10.1016/j.nic.2011.05.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The cerebral cortex develops in several stages from a pseudostratified epithelium at 5 weeks to an essentially complete cortex at 47 weeks. Cortical connectivity starts with thalamocortical connections in the 3rd trimester only and continues until well after birth. Vascularity adapts to proliferation and connectivity. Malformations of cortical development are classified into disorders of specification, proliferation/apoptosis, migration, and organization. However, all processes are intermingled, as for example a dysplastic cell may migrate incompletely and not connect appropriately. However, this classification is convenient for didactic purposes as long as the complex interactions between the different processes are kept in mind.
Collapse
|
16
|
The corpus callosum, the other great forebrain commissures, and the septum pellucidum: anatomy, development, and malformation. Neuroradiology 2010; 52:447-77. [PMID: 20422408 DOI: 10.1007/s00234-010-0696-3] [Citation(s) in RCA: 181] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2010] [Accepted: 03/29/2010] [Indexed: 12/13/2022]
Abstract
There are three telencephalic commissures which are paleocortical (the anterior commissure), archicortical (the hippocampal commissure), and neocortical. In non-placental mammals, the neocortical commissural fibers cross the midline together with the anterior and possibly the hippocampal commissure, across the lamina reuniens (joining plate) in the upper part of the lamina terminalis. In placental mammals, a phylogenetically new feature emerged, which is the corpus callosum: it results from an interhemispheric fusion line with specialized groups of mildline glial cells channeling the commissural axons through the interhemispheric meninges toward the contralateral hemispheres. This concerns the frontal lobe mainly however: commissural fibers from the temporo-occipital neocortex still use the anterior commissure to cross, and the posterior occipito-parietal fibers use the hippocampal commissure, forming the splenium in the process. The anterior callosum and the splenium fuse secondarily to form the complete commissural plate. Given the complexity of the processes involved, commissural ageneses are many and usually associated with other diverse defects. They may be due to a failure of the white matter to develop or to the commissural neurons to form or to migrate, to a global failure of the midline crossing processes or to a selective failure of commissuration affecting specific commissural sites (anterior or hippocampal commissures, anterior callosum), or specific sets of commissural axons (paleocortical, hippocampal, neocortical commissural axons). Severe hemispheric dysplasia may prevent the axons from reaching the midline on one or both sides. Besides the intrinsically neural defects, midline meningeal factors may prevent the commissuration as well (interhemispheric cysts or lipoma). As a consequence, commissural agenesis is a malformative feature, not a malformation by itself. Good knowledge of the modern embryological data may allow for a good understanding of a specific pattern in a given individual patient, paving the way for better clinical correlation and genetic counseling.
Collapse
|
17
|
Ormitti F, Summa A, Ventura E, Todeschini A, Pisani F, Cantalupo G. Aberrant Mid-Sagittal Fiber Tracts Visualized by Diffusion Tensor MR. Neuroradiol J 2010; 23:177-81. [DOI: 10.1177/197140091002300205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2009] [Accepted: 11/17/2009] [Indexed: 11/16/2022] Open
Abstract
In hemimegalencephaly, MR imaging often reveals mid-sagittal band-like structures between the lateral ventricles. We describe the clinical presentation, morphologic abnormalities, conventional MR imaging, diffusion tensor MR and fiber tract (FT) reconstruction in a 14-year-old boy with unilateral hemimegalencephaly. We retrospectively examined MR images to determine whether these structures are aberrant mid-sagittal fibers.
Collapse
Affiliation(s)
- F. Ormitti
- Neuroradiology Unit, Parma University Hospital; Parma, Italy
| | - A. Summa
- Neuroradiology Unit, Parma University Hospital; Parma, Italy
| | - E. Ventura
- Neuroradiology Unit, Parma University Hospital; Parma, Italy
| | - A. Todeschini
- Neuroradiology Unit, Modena Hospital NOCSA; Modena, Italy
| | - F. Pisani
- Child Neuropsychiatry Unit, Parma University Hospital; Parma, Italy
| | - G. Cantalupo
- Child Neuropsychiatry Unit, Parma University Hospital; Parma, Italy
| |
Collapse
|
18
|
Asymmetrical interhemispheric fiber tracts in patients with hemimegalencephaly on diffusion tensor magnetic resonance imaging. J Neuroradiol 2009; 36:249-54. [PMID: 19783304 DOI: 10.1016/j.neurad.2009.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2009] [Revised: 07/29/2009] [Accepted: 07/29/2009] [Indexed: 11/21/2022]
Abstract
OBJECTIVE The internal structures of cerebral white matter in patients with hemimegalencephaly have not yet been investigated except for one, which evaluated aberrant fibers. We examined interhemispheric fiber tracts (FT) passing through the corpus callosum using magnetic resonance (MR) diffusion tensor imaging (DTI). METHODS MR studies, including DTI, were performed in nine consecutive patients with hemimegalencephaly and in 11 patients with West syndrome as disease controls. The interhemispheric FT passing through the corpus callosum were evaluated in six regional geometric subdivisions in every hemimegalencephaly and West syndrome patient (54 and 66 subregions, respectively), and the distribution and volume differences between affected and unaffected hemispheres were all compared. RESULTS In patients with hemimegalencephaly, interhemispheric FT were symmetrically distributed in 27 (50%) of the 54 corpus callosum subregions. However, the FT were distributed to different areas in the same lobes in 22 (40%) subregions, and to different lobes in five (9%) subregions. FT volumes were symmetrical in 35 (65%) subregions, while FT volumes on the affected side were greater, but less than those on the unaffected side, in 14 (26%) and five (9%) subregions, respectively. In contrast, in the West syndrome patients, interhemispheric FT showed symmetrical distributions and volumes in all regions. CONCLUSION Asymmetrical interhemispheric FT are often observed in patients with hemimegalencephaly, and DTI was a useful means of elucidating the internal structures of white matter.
Collapse
|
19
|
Clinical and imaging characteristics of localized megalencephaly: a retrospective comparison of diffuse hemimegalencephaly and multilobar cortical dysplasia. Neuroradiology 2009; 51:821-30. [DOI: 10.1007/s00234-009-0579-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 07/22/2009] [Indexed: 11/27/2022]
|
20
|
Wahl M, Strominger Z, Jeremy RJ, Barkovich AJ, Wakahiro M, Sherr EH, Mukherjee P. Variability of homotopic and heterotopic callosal connectivity in partial agenesis of the corpus callosum: a 3T diffusion tensor imaging and Q-ball tractography study. AJNR Am J Neuroradiol 2009; 30:282-9. [PMID: 19001538 DOI: 10.3174/ajnr.a1361] [Citation(s) in RCA: 106] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
BACKGROUND AND PURPOSE Little is known about the anatomic connectivity of callosal axons in individuals with partial agenesis of the corpus callosum (pAgCC). We used tractography based on both diffusion tensor imaging (DTI) and high angular resolution diffusion imaging (HARDI) to investigate interhemispheric white matter connectivity in pAgCC. MATERIALS AND METHODS DTI and HARDI were performed at 3T on 6 individuals with pAgCC and 8 control subjects. For HARDI analysis, a Q-ball reconstruction method capable of visualizing multiple intravoxel fiber orientations was used. In both DTI and HARDI, whole-brain 3D fiber tractography was performed by using deterministic streamline algorithms. Callosal fibers were then segmented to identify separately connections between homologous cortical regions (homotopic fibers) and nonhomologous regions (heterotopic fibers) by using manually drawn regions of interest. RESULTS In control individuals, we observed densely connected homotopic fibers. However, in individuals with pAgCC, we identified not only homotopic connections but also heterotopic connections in 4 of 6 subjects. Furthermore, the observed homotopic connections in pAgCC did not necessarily correlate with the position or size of the residual callosum. The nature of homotopic and heterotopic connectivity varied considerably among subjects with pAgCC, and HARDI recovered more callosal fibers than DTI. CONCLUSION Individuals with pAgCC demonstrate a remarkable diversity of callosal connectivity, including a number of heterotopic tracts that are absent in healthy subjects. The patterns of their callosal connections cannot be predicted from the appearance of their callosal fragments on conventional MR imaging. More tracts and more extensive fibers within tracts are recovered with HARDI than with DTI.
Collapse
Affiliation(s)
- M Wahl
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA 94143-0628, USA
| | | | | | | | | | | | | |
Collapse
|