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Tiffany Cava Morden F, Xin Liang B, Nguyen L, Carrazana E, Ghaffari-Rafi A, Kai Liow K. Partial Rhombencephalosynapsis Presenting in an Adult with Cerebello-Trigeminal-Dermal Dysplasia. Epilepsy Behav Rep 2024; 27:100688. [PMID: 39050404 PMCID: PMC11268192 DOI: 10.1016/j.ebr.2024.100688] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2024] [Revised: 06/19/2024] [Accepted: 06/20/2024] [Indexed: 07/27/2024] Open
Abstract
Gomez-Lopez-Hernandez syndrome (GLHS), also known as cerebello-trigeminal-dermal dysplasia, is a neurocutaneous disorder typically presenting in childhood. GLHS is characterized by rhombencephalosynapsis (RES) and partial alopecia, with or without trigeminal anesthesia. We describe a rare case of GLHS in a paucisymptomatic adult who presented with new-onset seizure-like activity. Magnetic resonance imaging revealed partial midline fusion of the cerebellar hemispheres, incomplete development of vermis, and slight medialization of the dentate nuclei: all consistent with the diagnosis of RES. Radiographic evidence combined with partial alopecia, truncal ataxia, and muscular hypotonia are suggestive GLHS diagnosis. Our report not only highlights the importance of maintaining GLHS on the differential for new-onset seizure-like activity, but also demonstrates how patients with GLHS may be minimally symptomatic and diagnosed in adulthood. Lay Summary The Gomez-Lopez-Hernandez syndrome (GLHS), or cerebellotrigeminal-dermal dysplasia, is a rare condition that affects both the nervous system and the skin. It involves abnormal development of the brain, partial alopecia [thinning of hair], and loss of sensation in the face. One specific brain malformation, called rhombencephalosynapsis (RES), results from abnormal formation of the cerebellum and is seen in GHLS.Both RES and GLHS present early in childhood, and cases presenting later in life are exceptionally rare. Here we describe a young adult with RES and GLHS whose normal development and mild clumsiness eluded recognition by doctors until early adulthood when she presented with a single seizure.
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Affiliation(s)
| | - Bao Xin Liang
- University of Hawaiʻi at Mānoa, John A. Burns School of Medicine, Honolulu, HI, USA
| | - Linda Nguyen
- University of Hawaiʻi at Mānoa, John A. Burns School of Medicine, Honolulu, HI, USA
| | - Enrique Carrazana
- University of Hawaiʻi at Mānoa, John A. Burns School of Medicine, Honolulu, HI, USA
- Hawaii Pacific Neuroscience, Honolulu, HI, USA
- Neurelis, Inc., San Diego, CA, USA
| | - Arash Ghaffari-Rafi
- University of California, Davis, School of Medicine, Department of Neurological Surgery, Sacramento, CA, USA
| | - Kore Kai Liow
- University of Hawaiʻi at Mānoa, John A. Burns School of Medicine, Honolulu, HI, USA
- Hawaii Pacific Neuroscience, Honolulu, HI, USA
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2
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Fouda MA, Kim TY, Cohen AR. Rhomboencephalosynapsis: Review of the literature. World Neurosurg 2021; 159:48-53. [PMID: 34954057 DOI: 10.1016/j.wneu.2021.12.062] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 12/25/2022]
Abstract
Rhombencephalosynapsis is a rare congenital anomaly, characterized by partial or total agenesis of the cerebellar vermis with midline fusion of the cerebellar hemispheres, dentate nuclei, and the superior cerebellar peduncles, creating the distinctive Keyhole appearance of the fourth ventricle. Rhombencephalosynapsis can be isolated or can occur in association with other congenital anomalies and syndromes such as Gómez-López-Hernández Syndrome (GLHS) or VACTERL; vertebral anomalies (V), anal atresia (A), cardiovascular defects (C), esophageal atresia and/or tracheo-esophageal fistula (TE), renal (R) and limb/radial (L) anomalies. Recent advances in prenatal imaging have resulted in an increasing rate of prenatal diagnosis of abnormalities of the posterior fossa including Rhombencephalosynapsis. Patients with rhombencephalosynapsis may present with motor developmental delay, ataxia, swallowing difficulties, muscular hypotonia, spastic quadriparesis, abnormal eye movements and a characteristic "figure-of-eight" head shaking. Cognitive outcome varies from severe intellectual disability to normal intellectual function. Rhombencephalosynapsis with VACTERL is often associated with severe cognitive disabilities, whereas patients with GLHS may have better cognitive function. The most common associated findings with rhombencephalosynapsis include hydrocephalus, mesencephalosynapsis, holoprosencephaly, pontocerebellar hypoplasia, corpus callosum dysgenesis and absence of septum pellucidum. Patients can be categorized into four groups: (1) Rhombencephalosynapsis associated with Gómez-López-Hernández syndrome; (2) Rhombencephalosynapsis with VACTERL; (3) Rhombencephalosynapsis with atypical holoprosencephaly, and (4) isolated rhomboencephalosynapsis. The etiology of rhombencephalosynapsis is unknown. Here, we discuss several hypotheses about its etiology.
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Affiliation(s)
- Mohammed A Fouda
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD.
| | - Timothy Y Kim
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Alan R Cohen
- Division of Pediatric Neurosurgery, Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD
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3
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Krajden Haratz K, Oliveira Szejnfeld P, Govindaswamy M, Leibovitz Z, Gindes L, Severino M, Rossi A, Paladini D, Garcia Rodriguez R, Ben-Sira L, Borkowski Tillman T, Gupta R, Lotem G, Raz N, Hamamoto TENK, Kidron D, Arad A, Birnbaum R, Brussilov M, Pomar L, Vial Y, Leventer RJ, McGillivray G, Fink M, Krzeszowski W, Fernandes Moron A, Lev D, Tamarkin M, Shalev J, Har Toov J, Lerman-Sagie T, Malinger G. Prenatal diagnosis of rhombencephalosynapsis: neuroimaging features and severity of vermian anomaly. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2021; 58:864-874. [PMID: 33942916 DOI: 10.1002/uog.23660] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 03/24/2021] [Accepted: 04/16/2021] [Indexed: 06/12/2023]
Abstract
OBJECTIVES To describe the prenatal neuroimaging spectrum of rhombencephalosynapsis (RES) and criteria for its classification according to the severity of vermian anomaly. METHODS In this multicenter retrospective study of fetuses with RES between 2002 and 2020, the medical records and brain ultrasound and magnetic resonance images were evaluated comprehensively to determine the severity of the vermian anomaly and the presence of associated brain findings. RES was classified, according to the pattern of vermian agenesis and the extent of the fusion of the hemispheres, as complete RES (complete absence of the vermis) or partial RES (further classified according to the part of the vermis that was missing and, consequently, the region of hemispheric fusion, as anterior, posterior, severe or mixed RES). Findings were compared between cases with complete and those with partial RES. RESULTS Included in the study were 62 fetuses with a gestational age ranging between 12 and 37 weeks. Most had complete absence of the vermis (complete RES, 77.4% of cases), a 'round-shaped' cerebellum on axial views (72.6%) and a transverse cerebellar diameter (TCD) < 3rd centile (87.1%). Among the 22.6% of cases with partial RES, 6.5% were classified as severe partial, 6.5% as partial anterior, 8.1% as partial mixed and 1.6% as partial posterior. Half of these cases presented with normal or nearly normal cerebellar morphology and 28.5% had a TCD within the normal limits. Infratentorially, the fourth ventricle was abnormal in 88.7% of cases overall, and anomalies of the midbrain and pons were frequent (93.5% and 77.4%, respectively). Ventriculomegaly was observed in 80.6% of all cases, being more severe in cases with complete RES than in those with partial RES, with high rates of parenchymal and septal disruption. CONCLUSIONS This study provides prenatal neuroimaging criteria for the diagnosis and classification of RES, and identification of related features, using ultrasound and magnetic resonance imaging. According to our findings, a diagnosis of RES should be considered in fetuses with a small TCD (severe cerebellar hypoplasia) and/or a round-shaped cerebellum on axial views, during the second or third trimester, especially when associated with ventriculomegaly. Partial RES is more common than previously thought, but presents an extreme diagnostic challenge, especially in cases with normal or nearly-normal cerebellar morphobiometric features. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.
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Affiliation(s)
- K Krajden Haratz
- Fetal Neurology Multidisciplinary Group, Division of Ultrasound in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - P Oliveira Szejnfeld
- Instituto D'Or de Pesquisa e Ensino, Rio de Janeiro, Brazil
- DDI UNIFESP, São Paulo, Brazil
- Fundação Instituto de Pesquisa e Estudo de Diagnostico por Imagem, São Paulo, Brazil
| | - M Govindaswamy
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Z Leibovitz
- Ultrasound in Obstetrics and Gynecology Unit, Bnai-Zion Medical Center, Haifa, Israel
- Technion Faculty of Medicine, Haifa, Israel
- Fetal Neurology Clinic, Ultrasound in Obstetrics and Gynecology Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon, Israel
| | - L Gindes
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Fetal Neurology Clinic, Ultrasound in Obstetrics and Gynecology Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon, Israel
| | - M Severino
- Neuroradiology Unit, IRCCS Istituto Giannini Gaslini, Genoa, Italy
| | - A Rossi
- Neuroradiology Unit, IRCCS Istituto Giannini Gaslini, Genoa, Italy
- Department of Health Sciences (DISSAL), University of Genoa, Genoa, Italy
| | - D Paladini
- Fetal Medicine Unit, IRCCS Istituto G. Gaslini, Genoa, Italy
| | - R Garcia Rodriguez
- Complejo Hospitalario Insular Materno Infantil de Canarias, Las Palmas de Gran Canaria, Spain
| | - L Ben-Sira
- Fetal Neurology Multidisciplinary Group, Division of Ultrasound in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Pediatric Radiology Unit, Department of Radiology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - T Borkowski Tillman
- Fetal Neurology Multidisciplinary Group, Division of Ultrasound in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - R Gupta
- Sunehri Devi Hospital, Sonepat India, Indraprastha Apollo Hospital, New Delhi, India
| | - G Lotem
- Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon, Israel
| | - N Raz
- Technion Faculty of Medicine, Haifa, Israel
- Department of Obstetrics and Gynecology, Hillel Yaffe Medical Center, Hedera, Israel
| | - T E N K Hamamoto
- Departamento de Obstetrícia da Universidade Federal de São Paulo (EPM/UNIFESP), São Paulo, Brazil
| | - D Kidron
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Pathology, Meir Medical Center, Kfar Saba, Israel
| | - A Arad
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Pathology, Bnai Zion Medical Center, Haifa, Israel
| | - R Birnbaum
- Fetal Neurology Multidisciplinary Group, Division of Ultrasound in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - M Brussilov
- Fetal Neurology Multidisciplinary Group, Division of Ultrasound in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - L Pomar
- Ultrasound and Fetal Medicine Unit, Department Woman-Mother-Child, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - Y Vial
- Ultrasound and Fetal Medicine Unit, Department Woman-Mother-Child, Lausanne University Hospital and Lausanne University, Lausanne, Switzerland
| | - R J Leventer
- Department of Neurology, The Royal Children's Hospital, Murdoch Children's Research Institute and University of Melbourne Department of Pediatrics, Melbourne, Australia
| | - G McGillivray
- Royal Women's Hospital, Mercy Hospital for Women and Murdoch Children's Research Institute, Melbourne, Australia
| | - M Fink
- Department of Medical Imaging, The Royal Children's Hospital and Perinatal Unit, The Mercy Hospital for Women, Melbourne, Australia
| | | | - A Fernandes Moron
- Departamento de Obstetrícia da Universidade Federal de São Paulo (EPM/UNIFESP), São Paulo, Brazil
| | - D Lev
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Fetal Neurology Clinic, Ultrasound in Obstetrics and Gynecology Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon, Israel
- Institute of Genetics, Wolfson Medical Center, Holon, Israel
| | - M Tamarkin
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Fetal Neurology Clinic, Ultrasound in Obstetrics and Gynecology Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon, Israel
| | - J Shalev
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Fetal Neurology Clinic, Ultrasound in Obstetrics and Gynecology Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon, Israel
- Institute of Genetics, Wolfson Medical Center, Holon, Israel
| | - J Har Toov
- Fetal Neurology Multidisciplinary Group, Division of Ultrasound in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - T Lerman-Sagie
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
- Fetal Neurology Clinic, Ultrasound in Obstetrics and Gynecology Unit, Department of Obstetrics and Gynecology, Wolfson Medical Center, Holon, Israel
- Pediatric Neurology Unit, Wolfson Medical Center, Holon, Israel
| | - G Malinger
- Fetal Neurology Multidisciplinary Group, Division of Ultrasound in Obstetrics and Gynecology, Lis Maternity Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
- Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Diagnosis of rhomboencephalosynapsis by MRI in a 5-year-old child. Radiol Case Rep 2020; 15:867-870. [PMID: 32382369 PMCID: PMC7200622 DOI: 10.1016/j.radcr.2020.04.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/07/2020] [Accepted: 04/09/2020] [Indexed: 11/20/2022] Open
Abstract
Rhombencephalosynapsis is a rare defect in the development of the cerebellum, characterized by partial or total agenesis of the vermis, with fusion of the cerebellar hemispheres in the midline. It is usually related to Gómez-López-Hernández Syndrome (cerebellar-trigeminal dermal dysplasia) and VACTERL association association (vertebral defects, vascular anomalies, anal atresia, cardiac anomalies, tracheoesophageal fistula with esophageal atresia, renal dysplasia and limb anomalies). A 5-year-old female patient with spastic cerebral palsy and hydrocephalus presented here, neuroimages documented the next features: absence of cerebellar vermis, periventricular leukomalacia, cerebellar tonsils descent and rhombencephalosynapsis. Other important imaging findings and associations in these cases are discussed.
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Hamano T, Mutoh T, Naiki H, Shirafuji N, Ikawa M, Yamamura O, Dickson DW, Aiki S, Kuriyama M, Nakamoto Y. Subventricular glial nodules in neurofibromatosis 1 with craniofacial dysmorphism and occipital meningoencephalocele. eNeurologicalSci 2019; 17:100213. [PMID: 31799455 PMCID: PMC6881603 DOI: 10.1016/j.ensci.2019.100213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 10/18/2019] [Accepted: 11/17/2019] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Neurofibromatosis 1 (NF1) is autosomally inherited disorder, characterized by café au lait spots and multiple neurofibromas. Subventricular glial nodules (SVGN) are multiple gliosis bulging into the ventricular lumen, and histologically consist of astrocytes and their processes. Damage to ependymal cells induces SVGN formation. CASE REPORT This case report describes a 50-year-old man with NF1, craniofacial dysmorphism, including sphenoid dysplasia, bone defects at the middle posterior fossa, with disconnection of the parieto-occipital sutures, and the left orbital bone, and occipital meningoencephalocele. He died of status epileptics. Pathologically, many SVGN were found around the ventricular wall. Many ependymal cells were stripped during ventricular dilatation. Therefore, to prevent brain tissue insult from direct exposure to CSF, the proliferation of astrocytes and their processes was speculated to have substitute for ependymal cells and induced SVGN formation.
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Affiliation(s)
- Tadanori Hamano
- Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
- Department of Aging and Dementia (DAD), Faculty of Medical Sciences, University of Fukui, Fukui, Japan
- Life Science Innovation Center, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Tatsuro Mutoh
- Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
- Department of Neurology, Fujita Health University, Toyoake, Japan
| | - Hironobu Naiki
- Department of Pathological Sciences, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Norimichi Shirafuji
- Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
- Department of Aging and Dementia (DAD), Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Masamichi Ikawa
- Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Osamu Yamamura
- Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - Dennis W. Dickson
- Department of Neuropathology, Mayo Clinic College of Medicine, FL, USA
| | | | - Masaru Kuriyama
- Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
- Department of Neurology, Ota Memorial Hospital, Fukuyama, Japan
| | - Yasunari Nakamoto
- Second Department of Internal Medicine, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
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Aldinger KA, Dempsey JC, Tully HM, Grout ME, Mehaffey MG, Dobyns WB, Doherty D. Rhombencephalosynapsis: Fused cerebellum, confused geneticists. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2019; 178:432-439. [PMID: 30580482 DOI: 10.1002/ajmg.c.31666] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2018] [Revised: 10/27/2018] [Accepted: 10/29/2018] [Indexed: 11/07/2022]
Abstract
Rhombencephalosynapsis (RES) is a unique cerebellar malformation characterized by fusion of the cerebellar hemispheres with partial or complete absence of a recognizable cerebellar vermis. Subsets of patients also have other brain malformations such as midbrain fusion with aqueductal stenosis, characteristic craniofacial features (prominent forehead, flat midface, hypertelorism, ear abnormalities), and somatic malformations (heart, kidney, spine, and limb defects). Similar to known genetic brain malformations, the RES cerebellar malformation is highly stereotyped, yet no genetic causes have been identified. Here, we outline our current understanding of the genetic basis for RES, discuss limitations, and outline future approaches to identifying the causes of this fascinating brain malformation.
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Affiliation(s)
- Kimberly A Aldinger
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA
| | | | - Hannah M Tully
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA.,Department of Neurology, University of Washington, Seattle, Washington
| | - Megan E Grout
- Department of Pediatrics, University of Washington, Seattle, WA
| | | | - William B Dobyns
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA.,Department of Pediatrics, University of Washington, Seattle, WA.,Department of Neurology, University of Washington, Seattle, Washington
| | - Dan Doherty
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA.,Department of Pediatrics, University of Washington, Seattle, WA
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7
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De Mori R, Severino M, Mancardi MM, Anello D, Tardivo S, Biagini T, Capra V, Casella A, Cereda C, Copeland BR, Gagliardi S, Gamucci A, Ginevrino M, Illi B, Lorefice E, Musaev D, Stanley V, Micalizzi A, Gleeson JG, Mazza T, Rossi A, Valente EM. Agenesis of the putamen and globus pallidus caused by recessive mutations in the homeobox gene GSX2. Brain 2019; 142:2965-2978. [PMID: 31412107 PMCID: PMC6776115 DOI: 10.1093/brain/awz247] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 06/06/2019] [Accepted: 06/18/2019] [Indexed: 12/31/2022] Open
Abstract
Basal ganglia are subcortical grey nuclei that play essential roles in controlling voluntary movements, cognition and emotion. While basal ganglia dysfunction is observed in many neurodegenerative or metabolic disorders, congenital malformations are rare. In particular, dysplastic basal ganglia are part of the malformative spectrum of tubulinopathies and X-linked lissencephaly with abnormal genitalia, but neurodevelopmental syndromes characterized by basal ganglia agenesis are not known to date. We ascertained two unrelated children (both female) presenting with spastic tetraparesis, severe generalized dystonia and intellectual impairment, sharing a unique brain malformation characterized by agenesis of putamina and globi pallidi, dysgenesis of the caudate nuclei, olfactory bulbs hypoplasia, and anomaly of the diencephalic-mesencephalic junction with abnormal corticospinal tract course. Whole-exome sequencing identified two novel homozygous variants, c.26C>A; p.(S9*) and c.752A>G; p.(Q251R) in the GSX2 gene, a member of the family of homeobox transcription factors, which are key regulators of embryonic development. GSX2 is highly expressed in neural progenitors of the lateral and median ganglionic eminences, two protrusions of the ventral telencephalon from which the basal ganglia and olfactory tubercles originate, where it promotes neurogenesis while negatively regulating oligodendrogenesis. The truncating variant resulted in complete loss of protein expression, while the missense variant affected a highly conserved residue of the homeobox domain, was consistently predicted as pathogenic by bioinformatic tools, resulted in reduced protein expression and caused impaired structural stability of the homeobox domain and weaker interaction with DNA according to molecular dynamic simulations. Moreover, the nuclear localization of the mutant protein in transfected cells was significantly reduced compared to the wild-type protein. Expression studies on both patients' fibroblasts demonstrated reduced expression of GSX2 itself, likely due to altered transcriptional self-regulation, as well as significant expression changes of related genes such as ASCL1 and PAX6. Whole transcriptome analysis revealed a global deregulation in genes implicated in apoptosis and immunity, two broad pathways known to be involved in brain development. This is the first report of the clinical phenotype and molecular basis associated to basal ganglia agenesis in humans.
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Affiliation(s)
- Roberta De Mori
- Neurogenetics Unit, IRCCS Santa Lucia Foundation, Rome, Italy
| | | | | | - Danila Anello
- Neurogenetics Unit, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Silvia Tardivo
- Neurogenetics Unit, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Tommaso Biagini
- IRCCS Casa Sollievo della Sofferenza, Laboratory of Bioinformatics, San Giovanni Rotondo (FG), Italy
| | - Valeria Capra
- Neurosurgery Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | | | - Cristina Cereda
- Genomic and Postgenomic Lab, IRCCS Mondino Foundation, Pavia, Italy
| | - Brett R Copeland
- Laboratory for Pediatric Brain Diseases, Rady Children’s Institute for Genomic Medicine, University of California San Diego, Howard Hughes Medical Institute, La Jolla (CA), USA
| | - Stella Gagliardi
- Genomic and Postgenomic Lab, IRCCS Mondino Foundation, Pavia, Italy
| | - Alessandra Gamucci
- Child Neuropsychiatry Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Monia Ginevrino
- Neurogenetics Unit, IRCCS Santa Lucia Foundation, Rome, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Barbara Illi
- Institute of Molecular Biology and Pathology, National Research Council, Rome, Italy
| | - Elisa Lorefice
- Department of Molecular Medicine, Sapienza University, Rome, Italy
| | - Damir Musaev
- Laboratory for Pediatric Brain Diseases, Rady Children’s Institute for Genomic Medicine, University of California San Diego, Howard Hughes Medical Institute, La Jolla (CA), USA
| | - Valentina Stanley
- Laboratory for Pediatric Brain Diseases, Rady Children’s Institute for Genomic Medicine, University of California San Diego, Howard Hughes Medical Institute, La Jolla (CA), USA
| | - Alessia Micalizzi
- Laboratory of Medical Genetics, Bambino Gesù Children’s Hospital, Rome, Italy
| | - Joseph G Gleeson
- Laboratory for Pediatric Brain Diseases, Rady Children’s Institute for Genomic Medicine, University of California San Diego, Howard Hughes Medical Institute, La Jolla (CA), USA
| | - Tommaso Mazza
- IRCCS Casa Sollievo della Sofferenza, Laboratory of Bioinformatics, San Giovanni Rotondo (FG), Italy
| | - Andrea Rossi
- Neuroradiology Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Enza Maria Valente
- Neurogenetics Unit, IRCCS Santa Lucia Foundation, Rome, Italy
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
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Sarnat HB. The 2016 Bernard Sachs Lecture: Timing in Morphogenesis and Genetic Gradients During Normal Development and in Malformations of the Nervous System. Pediatr Neurol 2018; 83:3-13. [PMID: 29778488 DOI: 10.1016/j.pediatrneurol.2017.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 08/13/2017] [Accepted: 08/28/2017] [Indexed: 10/17/2022]
Abstract
Nervous system development is quadradimensional. Both normal ontogenesis and developmental malformations are explained in the context of the fourth dimension, timing. Timing of the onset of either the genetic expression of a mutation or an epigenetic event that may be teratogenic is primordial in determining morphogenesis and the forms of malformations with their functional consequences. Multiple genotypes may cause similar phenotypes or a single genotype with different degrees of retained normal genetic expression may result in variable phenotypes. In this treatise, examples are presented of these principles, including both delayed and precocious maturation of processes such as synaptogenesis that may be out of synchrony with other simultaneous processes of neuronal maturation. In postzygotic somatic mosaicism, timing of onset determines not only the character but also the extent of a lesion; focal cortical dysplasia IIb and hemimegalencephaly are the same disease, both sharing activation of the mTOR pathway as the primary mechanism; the difference is timing of onset within the 33 mitotic cycles of the periventricular neuroepithelium. Genetic expression often follows gradients along the 3 axes of the neural tube. Defective gradients often can be identified by their morphological result without knowing the precise mutation. Upregulation in the vertical axis produces hyperplasia or duplication of either dorsal or ventral structures, whereas downregulation yields hypoplasia or fusion in the midline of bilateral structures. Disorders of segmentation or neuromere formation in the neural tube are increasingly recognized as another pathogenesis of cerebral dysgenesis. Our recent investigations show the participation of the U-fibre layer beneath FCD in epileptic networks because of neuronal dispersion with elaborate synaptic plexi and a barrier to deep heterotopia.
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Affiliation(s)
- Harvey B Sarnat
- Departments of Paediatrics, Pathology (Neuropathology), and Clinical Neurosciences, University of Calgary Cumming School of Medicine and Alberta Children's Hospital Research Institute, Calgary, Alberta, Canada.
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9
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Cerebellar networks and neuropathology of cerebellar developmental disorders. HANDBOOK OF CLINICAL NEUROLOGY 2018; 154:109-128. [PMID: 29903435 DOI: 10.1016/b978-0-444-63956-1.00007-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The cerebellar system is a series of axonal projections and synaptic circuits as networks, similar to those of the limbic system and those subserving the propagation and spread of seizures. Three principal cerebellar networks are identified and cerebellar disease often affects components of the networks other than just the cerebellar cortex. Contemporary developmental neuropathology of the cerebellum is best considered in the context of alterations of developmental processes: embryonic segmentation and genetic gradients along the three axes of the neural tube, individual neuronal and glial cell differentiation, migration, synaptogenesis, and myelination. Precisely timed developmental processes may be delayed or precocious rhombencephalosynapsis and pontocerebellar hypoplasia exemplify opposite gradients in the horizontal axis. Chiari II malformation may be reconsidered as a disorder of segmentation rather than simply due to mechanical forces upon normally developing hindbrain structures. Cellular nodules in the roof of the fourth ventricle are heterotopia of histologically differentiated but architecturally disoriented and disorganized neurons and glial cells; they often are less mature immunocytochemically than similar cells in adjacent normal folia. Cell rests are nodules of undifferentiated neuroepithelial cells. Both are frequent in human fetuses and neonates. Axonal projections from heterotopia to adjacent cerebellar folia or nuclei are few or absent, hence these nodules are clinically silent despite neuronal differentiation.
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Telencephalic Flexure and Malformations of the Lateral Cerebral (Sylvian) Fissure. Pediatr Neurol 2016; 63:23-38. [PMID: 27590993 DOI: 10.1016/j.pediatrneurol.2016.05.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Accepted: 05/04/2016] [Indexed: 11/20/2022]
Abstract
After sagittal division of the prosencephalon at 4.5 weeks of gestation, the early fetal cerebral hemisphere bends or rotates posteroventrally from seven weeks of gestation. The posterior pole of the telencephalon thus becomes not the occipital but the temporal lobe as the telencephalic flexure forms the operculum and finally the lateral cerebral or Sylvian fissure. The ventral part is infolded to become the insula. The frontal and temporal lips of the Sylvian fissure, as well as the insula, all derive from the ventral margin of the primitive telencephalon, hence may be influenced by genetic mutations with a ventrodorsal gradient of expression. The telencephalic flexure also contributes to a shift of the hippocampus from a dorsal to a ventral position, the early rostral pole of the hippocampus becoming caudal and dorsal becoming ventral. The occipital horn is the most recent recess of the lateral ventricle, hence most vulnerable to anatomic variations that affect the calcarine fissure. Many major malformations include lack of telencephalic flexure (holoprosencephaly, extreme micrencephaly) or dysplastic Sylvian fissure (lissencephalies, hemimegalencephaly, schizencephaly). Although fissures and sulci are genetically programmed, mechanical forces of growth and volume expansion are proposed to be mainly extrinsic (including ventricles) for fissures and intrinsic for sulci. In fetal hydrocephalus, the telencephalic flexure is less affected because ventricular dilatation occurs later in gestation. Flexures can be detected prenatally by ultrasound and fetal magnetic resonance imaging and should be described neuropathologically in cerebral malformations.
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11
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Lipomatous Lumbar Mass with an Attached Digit and Associated Split Cord Malformation. Can J Neurol Sci 2014; 35:250-4. [DOI: 10.1017/s0317167100008738] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Background:A male infant was born with a digit attached to a skin-covered lumbar lipomatous mass and an underlying split cord malformation.Methods:Surgical removal of the mass was performed at four months-of-age. By this time the digit had grown a nail and imaging and histology showed ongoing development of articulated phalanges.Results:The lipomatous mass contained a long bone, a clavicle-and scapula-like structure and a variety of other mature germ layer derivatives. These features raised a number of diagnostic considerations, including: mature teratoma, hamartoma, rudimentary parasitic twin, lipomyelomeningocele and dorsal accessory limb.Conclusions:Based on review of the literature, the authors hypothesize that there is a pathogenetically related spectrum of skin-covered dorsal mass lesions, often associated with spinal dysraphism. These consist of a major lipomatous component and a variety of mature germ layer derivatives that can vary widely in their degree of anatomical organization from case to case.
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Choudhri AF, Patel RM, Wilroy RS, Pivnick EK, Whitehead MT. Trigeminal nerve agenesis with absence of foramina rotunda in Gómez-López-Hernández syndrome. Am J Med Genet A 2014; 167A:238-42. [DOI: 10.1002/ajmg.a.36830] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 09/16/2014] [Accepted: 09/19/2014] [Indexed: 11/08/2022]
Affiliation(s)
- Asim F. Choudhri
- Department of Radiology; University of Tennessee Health Science Center; Memphis Tennessee
- Department of Ophthalmology; University of Tennessee Health Science Center; Memphis Tennessee
- Department of Neurosurgery; University of Tennessee Health Science Center; Memphis Tennessee
- Le Bonheur Children's Hospital; Memphis Tennessee
| | - Rakesh M. Patel
- College of Medicine; University of Tennessee Health Science Center; Memphis Tennessee
| | - Robert S. Wilroy
- Le Bonheur Children's Hospital; Memphis Tennessee
- Department of Pediatrics; Division of Genetics; University of Tennessee Health Science Center; Memphis Tennessee
| | - Eniko K. Pivnick
- Department of Ophthalmology; University of Tennessee Health Science Center; Memphis Tennessee
- Le Bonheur Children's Hospital; Memphis Tennessee
- Department of Pediatrics; Division of Genetics; University of Tennessee Health Science Center; Memphis Tennessee
| | - Matthew T. Whitehead
- Department of Radiology; University of Tennessee Health Science Center; Memphis Tennessee
- Le Bonheur Children's Hospital; Memphis Tennessee
- Department of Radiology; Children's National Medical Center; Washington DC
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13
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Saneto R, Wyllie E. Surgically Treatable Epilepsy Syndromes in Infancy and Childhood. ACTA ACUST UNITED AC 2013. [DOI: 10.1201/b14113-11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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14
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Midbrain and hindbrain malformations: advances in clinical diagnosis, imaging, and genetics. Lancet Neurol 2013; 12:381-93. [PMID: 23518331 DOI: 10.1016/s1474-4422(13)70024-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Historically, the midbrain and hindbrain have been considered of secondary importance to the cerebrum, which has typically been acknowledged as the most important part of the brain. In the past, radiologists and pathologists did not regularly examine these structures-also known as the brainstem and cerebellum-because they are small and difficult to remove without damage. With recent developments in neuroimaging, neuropathology, and neurogenetics, many developmental disorders of the midbrain and hindbrain have emerged as causes of neurodevelopmental dysfunction. These research advances may change the way in which we treat these patients in the future and will enhance the clinical acumen of the practising neurologist and thereby improve the diagnosis and treatment of these patients.
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Weaver J, Manjila S, Bahuleyan B, Bangert BA, Cohen AR. Rhombencephalosynapsis: embryopathology and management strategies of associated neurosurgical conditions with a review of the literature. J Neurosurg Pediatr 2013; 11:320-6. [PMID: 23331215 DOI: 10.3171/2012.12.peds12188] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Rhombencephalosynapsis (RS) is a rare congenital posterior fossa malformation characterized by dorsal fusion of the cerebellar hemispheres, hypogenesis or agenesis of the vermis, and fusion of the dentate nuclei and superior cerebellar peduncles. The objective of this institutional study is to review the clinical conditions associated with RS and analyze the varied biological profile of this unique condition. METHODS The study data were collected retrospectively from the medical records of patients at Rainbow Babies and Children's Hospital. After required institutional review board approval, the authors obtained information regarding the cases of RS reviewed by the Departments of Radiology, Genetics, and/or Pediatric Neurology. Medical charts were systematically reviewed, and 9 patients were analyzed in detail. RESULTS The authors describe 6 cases of RS and 3 cases of partial RS. This case series demonstrates an association between RS and symptomatic hydrocephalus (7 of 9 patients) and RS and Chiari malformation (5 of 9 patients). Patients with symptomatic hydrocephalus underwent endoscopic third ventriculostomy or ventriculoperitoneal shunt insertion. One of the patients with an associated Chiari malformation underwent foramen magnum decompression. CONCLUSIONS The authors present a large case series of RS. Patients with RS often had hydrocephalus and/or a Chiari Type I or II hindbrain malformation. Neuroimaging findings of RS are presented along with hypotheses to explain the embryopathology of this unusual condition.
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Affiliation(s)
- John Weaver
- Division of Pediatric Neurosurgery & Minimally Invasive Neurosurgical Laboratory, Department of Radiology, University Hospitals Case Medical Center, Cleveland, Ohio, USA
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16
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Sarnat HB, Flores-Sarnat L, Auer RN. Sequence of Synaptogenesis in the Fetal and Neonatal Cerebellar System - Part 1: Guillain-Mollaret Triangle (Dentato-Rubro-Olivo-Cerebellar Circuit). Dev Neurosci 2013; 35:69-81. [DOI: 10.1159/000350503] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Accepted: 02/21/2013] [Indexed: 11/19/2022] Open
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Sarnat HB, Flores-Sarnat L. Neuroembryology and brain malformations: an overview. HANDBOOK OF CLINICAL NEUROLOGY 2013; 111:117-128. [PMID: 23622157 DOI: 10.1016/b978-0-444-52891-9.00012-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Modern neuroembryology integrates descriptive morphogenesis with more recent insight into molecular genetic programing and data enabled by cell-specific tissue markers that further define histogenesis. Maturation of individual neurons involves the development of energy pumps to maintain membrane excitability, ion channels, and membrane receptors. Most malformations of the nervous system are best understood in the context of aberrations of normal developmental processes that result in abnormal structure and function. Early malformations usually are disorders of genetic expression along gradients of the three axes of the neural tube, defective segmentation, or mixed lineages of individual cells. Later disorders mainly involve cellular migrations, axonal pathfinding, synaptogenesis, and myelination. Advances in neuroimaging now enable the diagnosis of many malformations in utero, at birth, or in early infancy in the living patient by abnormal macroscopic form of the brain. These images are complimented by modern neuropathological methods that disclose microscopic, immunocytochemical, and subcellular details beyond the resolution of MRI. Correlations may be made of both normal and abnormal ontogenesis with clinical neurological and EEG maturation in the preterm or term neonate for a better understanding of perinatal neurological disease. Precision in terminology is a key to scientific communication.
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Affiliation(s)
- Harvey B Sarnat
- Departments of Clinical Neurosciences and Paediatrics, Division of Paediatric Neurology, University of Calgary, Alberta Children's Hospital, Calgary, Canada.
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Merlini L, Fluss J, Korff C, Hanquinet S. Partial rhombencephalosynapsis and Chiari type II malformation in a child: a true association supported by DTI tractography. THE CEREBELLUM 2012; 11:227-32. [PMID: 21833660 DOI: 10.1007/s12311-011-0300-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Partial rhombencephalosynapsis (PRECS) has been recently reported in association with Chiari II (CII). However, its existence as a true malformation is challenged due to the anatomical changes potentially induced by CII. The aim of this report was to investigate the contribution of midbrain/hindbrain tractography in this setting. A 13-year-old boy with a known CII malformation and operated myelomeningocele was referred for brain imaging after a first complex partial seizure. In addition to the classical features of CII, MRI showed partially fused cerebellar hemispheres and multiple supratentorial abnormalities. Diffusion tensor imaging (DTI) color map and tractography showed absent transverse fibers on the midsection of the cerebellum, scarce fibers of the middle cerebellar peduncle (MCP), absence of the middle pontine crossing tract, and fibers running vertically in the medial part of the cerebellum. Vertical mediocerebellar fibers are a feature of classical RECS and the paucity or absence of MCP fibers is mainly described in CII. In our patient, DTI and FT therefore demonstrated structural characteristics of both RECS and CII confirming their potential coexistence and suggesting possible shared embryological pathway.
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Affiliation(s)
- Laura Merlini
- Unit of Pediatric Radiology, Geneva University Hospital, 6, Willy-Donzé, 1205 Geneva, Switzerland.
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19
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Tully HM, Dempsey JC, Ishak GE, Adam MP, Curry CJR, Sanchez-Lara P, Hunter A, Gripp KW, Allanson J, Cunniff C, Glass I, Millen KJ, Doherty D, Dobyns WB. Beyond Gómez-López-Hernández syndrome: recurring phenotypic themes in rhombencephalosynapsis. Am J Med Genet A 2012; 158A:2393-406. [PMID: 22965664 PMCID: PMC3448816 DOI: 10.1002/ajmg.a.35561] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2012] [Accepted: 06/20/2012] [Indexed: 11/07/2022]
Abstract
Rhombencephalosynapsis (RES) is an uncommon cerebellar malformation characterized by fusion of the hemispheres without an intervening vermis. Frequently described in association with Gómez-López-Hernández syndrome, RES also occurs in conjunction with VACTERL features and with holoprosencephaly (HPE). We sought to determine the full phenotypic spectrum of RES in a large cohort of patients. Information was obtained through database review, patient questionnaire, radiographic, and morphologic assessment, and statistical analysis. We assessed 53 patients. Thirty-three had alopecia, 3 had trigeminal anesthesia, 14 had VACTERL features, and 2 had HPE with aventriculy. Specific craniofacial features were seen throughout the cohort, but were more common in patients with alopecia. We noted substantial overlap between groups. We conclude that although some distinct subgroups can be delineated, the overlapping features seen in our cohort suggest an underlying spectrum of RES-associated malformations rather than a collection of discrete syndromes.
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Affiliation(s)
- Hannah M Tully
- Division of Pediatric Neurology, Department of Neurology, University of Washington, Seattle, USA.
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Guleria S, Kelly T, Maheshwari M, Segall H. An Atypical Case of Chiari II Malformation Mimicking Partial Rhombencephalosynapsis. Neuroradiol J 2012; 25:528-32. [DOI: 10.1177/197140091202500505] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 10/18/2012] [Indexed: 11/16/2022] Open
Abstract
Partial rhombencephalosynapsis in the presence of Chiari II malformation has been proposed as a “new abnormality of the hindbrain and spine“. We describe a case of Chiari II malformation with imaging features mimicking partial rhombencephalosynapsis. Our case demonstrates how the imaging findings of Chiari II malformation can be confused with the above entity and highlights the differentiating features to help radiologists make an accurate diagnosis.
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Affiliation(s)
- S. Guleria
- Pediatric Radiology, Children's Hospital of Wisconsin; Milwaukee, Wisconsin, USA
| | - T.G. Kelly
- Pediatric Radiology, Children's Hospital of Wisconsin; Milwaukee, Wisconsin, USA
| | - M. Maheshwari
- Pediatric Radiology, Children's Hospital of Wisconsin; Milwaukee, Wisconsin, USA
| | - H.D. Segall
- Pediatric Radiology, Children's Hospital of Wisconsin; Milwaukee, Wisconsin, USA
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Paprocka J, Jamroz E, Scieszka E, Kluczewska E. Isolated rhomboencephalosynapsis - a rare cerebellar anomaly. Pol J Radiol 2012; 77:47-9. [PMID: 22802865 PMCID: PMC3389961 DOI: 10.12659/pjr.882587] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Accepted: 01/19/2012] [Indexed: 11/26/2022] Open
Abstract
Background: Rhomboencephalosynapsis (RES, RS) is a unique entity usually recognized in infancy based on neuroimaging. Cerebellar fusion and absence of cerebellar vermis is often associated with supratentorial findings. Since now there are about 50 cases described worldwide, with approximately 36 patients diagnosed by MRI. The authors present the first in Poland case of this uncommon malformation and review the literature. Case Report: The authors describe a 28-month-old-girl with microcephaly and proper psychomotor development. The family history was unrelevant. Based on MRI the congenital malformation of posterior fossa-rhombencephalosynapsis was confirmed Conclusions: Presented patient is a typical example of MRI usefulness especially in patients with RES. RES symptoms are mild and that is why the diagnosis is usually made only in adulthood.
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Affiliation(s)
- Justyna Paprocka
- Child Neurology Department, Medical University of Silesia, Katowice, Poland
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22
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Millichap JG. Rhombencephalosynapsis Spectrum of Severity. Pediatr Neurol Briefs 2012. [DOI: 10.15844/pedneurbriefs-26-6-11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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23
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Ishak GE, Dempsey JC, Shaw DWW, Tully H, Adam MP, Sanchez-Lara PA, Glass I, Rue TC, Millen KJ, Dobyns WB, Doherty D. Rhombencephalosynapsis: a hindbrain malformation associated with incomplete separation of midbrain and forebrain, hydrocephalus and a broad spectrum of severity. Brain 2012; 135:1370-86. [PMID: 22451504 PMCID: PMC3338925 DOI: 10.1093/brain/aws065] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 01/28/2012] [Accepted: 01/29/2012] [Indexed: 12/11/2022] Open
Abstract
Rhombencephalosynapsis is a midline brain malformation characterized by missing cerebellar vermis with apparent fusion of the cerebellar hemispheres. Rhombencephalosynapsis can be seen in isolation or together with other central nervous system and extra-central nervous system malformations. Gómez-López-Hernández syndrome combines rhombencephalosynapsis with parietal/temporal alopecia and sometimes trigeminal anaesthesia, towering skull shape and dysmorphic features. Rhombencephalosynapsis can also be seen in patients with features of vertebral anomalies, anal atresia, cardiovascular anomalies, trachea-oesophageal fistula, renal anomalies, limb defects (VACTERL) association. Based on a comprehensive evaluation of neuroimaging findings in 42 patients with rhombencephalosynapsis, we propose a spectrum of severity, ranging from mild (the partial absence of nodulus, anterior and posterior vermis), to moderate (the absence of posterior vermis with some anterior vermis and nodulus present), to severe (the absence of posterior and anterior vermis with some nodulus present), to complete (the absence of the entire vermis including nodulus). We demonstrate that the severity of rhombencephalosynapsis correlates with fusion of the tonsils, as well as midbrain abnormalities including aqueductal stenosis and midline fusion of the tectum. Rhombencephalosynapsis is also associated with multiple forebrain abnormalities including absent olfactory bulbs, dysgenesis of the corpus callosum, absent septum pellucidum and, in rare patients, atypical forms of holoprosencephaly. The frequent association between rhombencephalosynapsis and aqueductal stenosis prompted us to evaluate brain magnetic resonance images in other patients with aqueductal stenosis at our institution, and remarkably, we identified rhombencephalosynapsis in 9%. Strikingly, subjects with more severe rhombencephalosynapsis have more severely abnormal neurodevelopmental outcome, as do subjects with holoprosencephaly and patients with VACTERL features. In summary, our data provide improved diagnostic and prognostic information, and support disruption of dorsal-ventral patterning as a mechanism underlying rhombencephalosynapsis.
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Affiliation(s)
- Gisele E. Ishak
- 1 Department of Radiology, University of Washington, Seattle Children’s Hospital, Seattle, WA 98105, USA
| | - Jennifer C. Dempsey
- 2 Division of Genetic Medicine, Department of Paediatrics, University of Washington, Seattle, WA 98195, USA
| | - Dennis W. W. Shaw
- 1 Department of Radiology, University of Washington, Seattle Children’s Hospital, Seattle, WA 98105, USA
- 3 Centre for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Hannah Tully
- 3 Centre for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
- 4 Department of Neurology, University of Washington, Seattle, WA 98195, USA
| | - Margaret P. Adam
- 2 Division of Genetic Medicine, Department of Paediatrics, University of Washington, Seattle, WA 98195, USA
| | - Pedro A. Sanchez-Lara
- 5 Department of Paediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
- 6 Children's Hospital Los Angeles, Los Angeles, CA 90027, USA
| | - Ian Glass
- 2 Division of Genetic Medicine, Department of Paediatrics, University of Washington, Seattle, WA 98195, USA
| | - Tessa C. Rue
- 7 Department of Biostatistics, University of Washington, Seattle, WA 98195, USA
| | - Kathleen J. Millen
- 2 Division of Genetic Medicine, Department of Paediatrics, University of Washington, Seattle, WA 98195, USA
- 3 Centre for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - William B. Dobyns
- 2 Division of Genetic Medicine, Department of Paediatrics, University of Washington, Seattle, WA 98195, USA
- 3 Centre for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Dan Doherty
- 2 Division of Genetic Medicine, Department of Paediatrics, University of Washington, Seattle, WA 98195, USA
- 3 Centre for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
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Fotos J, Olson R, Kanekar S. Embryology of the Brain and Molecular Genetics of Central Nervous System Malformation. Semin Ultrasound CT MR 2011; 32:159-66. [DOI: 10.1053/j.sult.2011.02.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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27
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Brain cancer stem cells: current status on glioblastoma multiforme. Cancers (Basel) 2011; 3:1777-97. [PMID: 24212782 PMCID: PMC3757390 DOI: 10.3390/cancers3021777] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 03/03/2011] [Accepted: 03/22/2011] [Indexed: 01/15/2023] Open
Abstract
Glioblastoma multiforme (GBM), an aggressive brain tumor of astrocytic/neural stem cell origin, represents one of the most incurable cancers. GBM tumors are highly heterogeneous. However, most tumors contain a subpopulation of cells that display neural stem cell characteristics in vitro and that can generate a new brain tumor upon transplantation in mice. Hence, previously identified molecular pathways regulating neural stem cell biology were found to represent the cornerstone of GBM stem cell self-renewal mechanism. GBM tumors are also notorious for their resistance to radiation therapy. Notably, GBM "cancer stem cells" were also found to be responsible for this radioresistance. Herein, we will analyze the data supporting or not the cancer stem cell model in GBM, overview the current knowledge regarding GBM stem cell self-renewal and radioresistance molecular mechanisms, and discuss the potential therapeutic application of these findings.
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Heteropagus (parasitic) twins: a review. J Pediatr Surg 2010; 45:2454-63. [PMID: 21129567 DOI: 10.1016/j.jpedsurg.2010.07.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Revised: 07/06/2010] [Accepted: 07/06/2010] [Indexed: 11/21/2022]
Abstract
Heteropagus, or "parasitic," twins are asymmetric conjoined twins in which the tissues of a severely defective twin (parasite) are dependent on the cardiovascular system of the other, largely intact twin (autosite) for survival. The estimated incidence of heteropagus twins is approximately 1 per 1 million live births. Isolated case reports comprise most of published work on this rare congenital anomaly. In the past, review articles have focused narrowly on one particular anatomical subtype of parasitic twin and/or on the anatomicopathology observed. Here, we present the epidemiology, proposed pathoembryogenic origins, anatomical abnormalities, management, and outcomes of the wide array of heteropagus twins described in the English language literature.
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Tan U. Uner tan syndrome: history, clinical evaluations, genetics, and the dynamics of human quadrupedalism. Open Neurol J 2010; 4:78-89. [PMID: 21258577 PMCID: PMC3024602 DOI: 10.2174/1874205x01004010078] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2010] [Revised: 06/14/2010] [Accepted: 06/15/2010] [Indexed: 11/22/2022] Open
Abstract
This review includes for the first time a dynamical systems analysis of human quadrupedalism in Uner Tan syndrome, which is characterized by habitual quadrupedalism, impaired intelligence, and rudimentary speech. The first family was discovered in a small village near Iskenderun, and families were later found in Adana and two other small villages near Gaziantep and Canakkale. In all the affected individuals dynamic balance was impaired during upright walking, and they habitually preferred walking on all four extremities. MRI scans showed inferior cerebellovermian hypoplasia with slightly simplified cerebral gyri in three of the families, but appeared normal in the fourth. PET scans showed a decreased glucose metabolic activity in the cerebellum, vermis and, to a lesser extent the cerebral cortex, except for one patient, whose MRI scan also appeared to be normal. All four families had consanguineous marriages in their pedigrees, suggesting autosomal recessive transmission. The syndrome was genetically heterogeneous. Since the initial discoveries more cases have been found, and these exhibit facultative quadrupedal locomotion, and in one case, late childhood onset. It has been suggested that the human quadrupedalism may, at least, be a phenotypic example of reverse evolution. From the viewpoint of dynamic systems theory, it was concluded there may not be a single factor that predetermines human quadrupedalism in Uner Tan syndrome, but that it may involve self-organization, brain plasticity, and rewiring, from the many decentralized and local interactions among neuronal, genetic, and environmental subsystems.
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Affiliation(s)
- Uner Tan
- Department of Physiology, Çukurova University, Medical School, 01330 Adana, Turkey
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Guntur Ramkumar P, Kanodia AK, Ananthakrishnan G, Roberts R. Chiari II malformation mimicking partial rhombencephalosynapsis? A case report. THE CEREBELLUM 2010; 9:111-4. [PMID: 19821003 DOI: 10.1007/s12311-009-0132-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Rhombencephalosynapsis is a rare congenital intracranial malformation with very few cases reported in literature. Partial rhombencephalosynapsis is a variation of this anomaly with fewer reported cases. We present the case of a patient with Chiari II malformation mimicking partial rhombencephalosynapsis.
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Jurkiewicz E, Dobrzańska A, Nowak K, Pleskaczyńska A. MRI findings in the young infant with brainstem disconnection and extracerebral features. Report of one case and review of the literature. Brain Dev 2010; 32:495-8. [PMID: 19443152 DOI: 10.1016/j.braindev.2009.04.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2009] [Revised: 03/28/2009] [Accepted: 04/10/2009] [Indexed: 11/26/2022]
Abstract
We present the young infant with the extremely rare brain abnormality-brainstem disconnection. Additionally, several extracerebral abnormalities were diagnosed: bilateral anotia, micrognatia, hypertelorism, scoliosis, ribs and vertebral anomalies. MR brain examination precisely demonstrated absence of the pons, with disruption between midbrain and hypoplastic medulla oblongata. The thin strands connecting the medulla with the midbrain and medulla with both cerebellar hemispheres were revealed. The large hamartoma of the tuber cinereum was found. In this study we review case reports published previously.
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Affiliation(s)
- Elzbieta Jurkiewicz
- MR Unit, Department of Diagnostic Imaging, The Children's Memorial Health Institute, Warsaw, Poland.
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Juranek J, Salman MS. Anomalous development of brain structure and function in spina bifida myelomeningocele. DEVELOPMENTAL DISABILITIES RESEARCH REVIEWS 2010; 16:23-30. [PMID: 20419768 PMCID: PMC2917986 DOI: 10.1002/ddrr.88] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Spina bifida myelomeningocele (SBM) is a specific type of neural tube defect whereby the open neural tube at the level of the spinal cord alters brain development during early stages of gestation. Some structural anomalies are virtually unique to individuals with SBM, including a complex pattern of cerebellar dysplasia known as the Chiari II malformation. Other structural anomalies are not necessarily unique to SBM, including altered development of the corpus callosum and posterior fossa. Within SBM, tremendous heterogeneity is reflected in the degree to which brain structures are atypical in qualitative appearance and quantitative measures of morphometry. Hallmark structural features of SBM include overall reductions in posterior fossa and cerebellum size and volume. Studies of the corpus callosum have shown complex patterns of agenesis or hypoplasia along its rostral-caudal axis, with rostrum and splenium regions particularly susceptible to agenesis. Studies of cortical regions have demonstrated complex patterns of thickening, thinning, and gyrification. Diffusion tensor imaging studies have reported compromised integrity of some specific white matter pathways. Given equally complex ocular motor, motor, and cognitive phenotypes consisting of relative strengths and weaknesses that seem to align with altered structural development, studies of SBM provide new insights to our current understanding of brain structure-function associations.
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Affiliation(s)
- Jenifer Juranek
- Department of Pediatrics, Children's Learning Institute, University of Texas Health Science Center at Houston, Houston, Texas 77030, USA.
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Abstract
INTRODUCTION Chiari type II malformation (CII) is a developmental deformity of the hindbrain. We have previously reported that many patients with CII have impaired smooth pursuit, while few make inaccurate saccades or have an abnormal vestibuloocular reflex. In contrast, saccadic adaptation and visual fixation are normal. In this report, we correlate results from several eye movement studies with neuroimaging in CII. We present a model for structural changes within the cerebellum in CII. METHODS Saccades, smooth pursuit, the vestibulo-ocular reflex, and visual fixation were recorded in 21 patients with CII, aged 8-19 years and 39 age-matched controls, using an infrared eye tracker. Qualitative and quantitative MRI data were correlated with eye movements in 19 CII patients and 28 controls. RESULTS Nine patients with CII had abnormal eye movements. Smooth pursuit gain was subnormal in eight, saccadic accuracy abnormal in four, and vestibulo-ocular reflex gain abnormal in three. None had fixation instability. Patients with CII had a significantly smaller cerebellar volume than controls, and those with normal eye motion had an expanded midsagittal vermis compared to controls. However, patients with abnormal eye movements had a smaller (non-expanded) midsagittal vermis area, posterior fossa area and medial cerebellar volumes than CII patients with normal eye movements. CONCLUSIONS The deformity of CII affects the structure and function of the cerebellum selectively and differently in those with abnormal eye movements. We propose that the vermis can expand when compressed within a small posterior fossa in some CII patients, thus sparing its ocular motor functions.
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Barkovich AJ, Millen KJ, Dobyns WB. A developmental and genetic classification for midbrain-hindbrain malformations. Brain 2009; 132:3199-230. [PMID: 19933510 PMCID: PMC2792369 DOI: 10.1093/brain/awp247] [Citation(s) in RCA: 167] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2009] [Revised: 08/04/2009] [Accepted: 08/21/2009] [Indexed: 01/30/2023] Open
Abstract
Advances in neuroimaging, developmental biology and molecular genetics have increased the understanding of developmental disorders affecting the midbrain and hindbrain, both as isolated anomalies and as part of larger malformation syndromes. However, the understanding of these malformations and their relationships with other malformations, within the central nervous system and in the rest of the body, remains limited. A new classification system is proposed, based wherever possible, upon embryology and genetics. Proposed categories include: (i) malformations secondary to early anteroposterior and dorsoventral patterning defects, or to misspecification of mid-hindbrain germinal zones; (ii) malformations associated with later generalized developmental disorders that significantly affect the brainstem and cerebellum (and have a pathogenesis that is at least partly understood); (iii) localized brain malformations that significantly affect the brain stem and cerebellum (pathogenesis partly or largely understood, includes local proliferation, cell specification, migration and axonal guidance); and (iv) combined hypoplasia and atrophy of putative prenatal onset degenerative disorders. Pertinent embryology is discussed and the classification is justified. This classification will prove useful for both physicians who diagnose and treat patients with these disorders and for clinical scientists who wish to understand better the perturbations of developmental processes that produce them. Importantly, both the classification and its framework remain flexible enough to be easily modified when new embryologic processes are described or new malformations discovered.
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Affiliation(s)
- A James Barkovich
- Neuroradiology Room L371, University of California at San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628, USA.
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Abstract
The cerebellum arises from two anatomically and molecularly different proliferative compartments: the cerebellar ventricular zone and the rhombic lip. The protracted development makes the cerebellum vulnerable to a broad spectrum of developmental disorders, of which the more frequent (the Dandy-Walker and related malformations and the pontocerebellar hypoplasias) are discussed in this article. Several genes for congenital malformations of the human cerebellum have recently been identified, including genes causing Joubert syndrome, the Dandy-Walker malformation, and pontocerebellar hypoplasias.
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Affiliation(s)
- Hans J Ten Donkelaar
- Department of Neurology, 935, Radboud University Nijmegen Medical Center, Reinier Postlaan 4, 6525 GC, PO Box 9101, 6500 HB Nijmegen, The Netherlands.
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Malformations of the Midbrain and Hindbrain: A Retrospective Study and Review of the Literature. THE CEREBELLUM 2009; 8:355-65. [DOI: 10.1007/s12311-009-0104-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2008] [Accepted: 03/19/2009] [Indexed: 10/20/2022]
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Arpino C, Volzone A, Curatolo P. Educational, cognitive, behavioral and language development issues. HANDBOOK OF CLINICAL NEUROLOGY 2008; 87:611-625. [PMID: 18809047 DOI: 10.1016/s0072-9752(07)87033-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- Carla Arpino
- Pediatric Neurology Unit, Department of Neuroscience, Tor Vergata University of Rome, Rome, Italy.
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Kumakura A, Takahara T, Asada J, Matsukawa Y, Hata D. Split notochord syndrome with congenital unilateral Horner's sign. Pediatr Neurol 2008; 38:47-9. [PMID: 18054693 DOI: 10.1016/j.pediatrneurol.2007.08.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2006] [Revised: 08/24/2006] [Accepted: 08/20/2007] [Indexed: 11/30/2022]
Abstract
A 2-year-old boy exhibited congenital right Horner's sign and right finger, wrist, and elbow flexion arthrogryposis. He had dyspnea and feeding difficulty 12 hours after birth. Radiologic examination revealed a thoracoabdominal intestinal tube and mediastinal cystic lesion at the right side, with vertebral anomaly at the cervical level. Histopathologically, the intestinal tube was diagnosed as bowel duplication. Because the mediastinal lesion could not be resected surgically, no histopathological diagnosis was made. Embryologically, the combination of transdiaphragmatic duplication, mediastinal cystic lesion, anterior spina bifida, and hemivertebra suggested notochord malformation. The diagnosis was split notochord syndrome, an extremely rare embryological malformation syndrome. Congenital unilateral Horner syndrome often has unknown etiology. In this case, cervical vertebral anomalies and mediastinal cystic lesion implied a compressed nerve root, resulting in Horner syndrome and right finger, wrist, and elbow flexion joint contracture. Split notochord syndrome should be included in differential diagnosis of congenital unilateral Horner syndrome.
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Affiliation(s)
- Akira Kumakura
- Department of Pediatrics, Kitano Hospital, The Tazuke Kofukai Medical Research Institute, Osaka, Japan
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Wong M. Mechanisms of epileptogenesis in tuberous sclerosis complex and related malformations of cortical development with abnormal glioneuronal proliferation. Epilepsia 2007; 49:8-21. [PMID: 17727667 PMCID: PMC3934641 DOI: 10.1111/j.1528-1167.2007.01270.x] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Malformations of cortical development (MCDs) are increasingly recognized as causes of medically intractable epilepsy. In order to develop more effective, rational therapies for refractory epilepsy related to MCDs, it is important to achieve a better understanding of the underlying mechanisms of epileptogenesis, but this is complicated by the wide variety of different radiographic, histopathological, and molecular features of these disorders. A subset of MCDs share a number of characteristic cellular and molecular abnormalities due to early defects in neuronal and glial proliferation and differentiation and have a particularly high incidence of epilepsy, suggesting that this category of MCDs with abnormal glioneuronal proliferation may also share a common set of primary mechanisms of epileptogenesis. This review critically analyzes both clinical and basic science evidence for overlapping mechanisms of epileptogenesis in this group of disorders, focusing on tuberous sclerosis complex, focal cortical dysplasia with balloon cells, and gangliogliomas. Specifically, the role of lesional versus perilesional regions, circuit versus cellular/molecular defects, and nonneuronal factors, such as astrocytes, in contributing to epileptogenesis in these MCDs is examined. An improved understanding of these various factors involved in epileptogenesis has direct clinical implications for optimizing current treatments or developing novel therapeutic approaches for epilepsy in these disorders.
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Affiliation(s)
- Michael Wong
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
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40
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Vattoth S, Pandey T, Al Tawari AA, Makar R, Ibrahim Abdulla JK. Partial Rhombencephalosynapsis of the Superior Cerebellum Associated with GM1 Gangliosidosis. Neuroradiol J 2007; 20:182-5. [PMID: 24299640 DOI: 10.1177/197140090702000208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2007] [Accepted: 02/18/2007] [Indexed: 11/15/2022] Open
Affiliation(s)
- S Vattoth
- Department Clinical Radiology, Al Sabah Hospital; Kuwait -
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41
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Focal cerebral mantle disruption in fetal hydrocephalus. Pediatr Neurol 2007; 36:236-43. [PMID: 17437906 DOI: 10.1016/j.pediatrneurol.2006.12.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2006] [Revised: 10/23/2006] [Accepted: 12/28/2006] [Indexed: 11/25/2022]
Abstract
A variety of developmental brain anomalies have been described in individuals with fetal hydrocephalus, regardless of etiology. Examples include callosal dysgenesis, periventricular gray matter heterotopia, hippocampal and white matter hypoplasia, and cortical polygyration. The present report draws attention to another anomaly not reported in previous case series of fetal hydrocephalus: focal cerebral mantle disruption. Neonatal imaging findings (where available) and post-shunt, stable-state magnetic resonance imaging, or pathological findings were reviewed in 77 subjects with fetal hydrocephalus (55 myelomeningocele, 16 sporadic aqueductal stenosis, 6 miscellaneous). Of these, 12 subjects (15.6%) demonstrated a combination of absence of the septum pellucidum and severe thinning or absence of the posteromesial cerebral mantle. On axial sequences, this combination created the illusion of a common ventricle, as in lobar holoprosencephaly. All 12 subjects had massive hydrocephalus at birth, accompanied in 7 by posteromesial ventricular diverticula. Two subjects, and one other subject with distinct lateral ventricles, demonstrated unilateral or bilateral mantle clefts suggestive of schizencephaly. Close radiological (n = 2) or pathological (n = 1) inspection showed that the clefts were only partially lined with gray matter and contained a transverse gliotic membrane. These findings are consistent with the hypothesis that massive early fetal hydrocephalus may completely disrupt cerebral mantle formation, particularly in the posteromesial hemispheres.
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Russo R, Fallet-Bianco C. Isolated posterior cerebellar vermal defect: a morphological study of midsagittal cerebellar vermis in 4 fetuses--early stage of Dandy-Walker continuum or new vermal dysgenesis? J Child Neurol 2007; 22:492-500; discussion 501. [PMID: 17621537 DOI: 10.1177/0883073807299862] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This report is a neuropathological description of posterior cerebellar vermis agenesis/hypoplasia at midgestation. This defect was demonstrated by prenatal ultrasound in four 21- to 24-week-old fetuses. Neuropathological findings were characterized macroscopically by hypoplasia of the posterior vermis with normal cerebellar hemispheres and brainstem; hypoplasia of the posterior vermian lobules 6 to 10, mildly cystic dilatation of the ventricular cavity, and a flat profile of the roof of the fourth ventricle also were demonstrated. Microscopically, a hypercellular and abnormally located germinal matrix and abnormal migration of external granule cell precursors into the meningeal tissue above the outer surface of the cerebellum were found. These abnormalities might result in delayed growth and foliation of the posterior vermian lobules. This feature might be the neuropathological pattern of the early stage of the Dandy-Walker continuum, although it cannot be excluded as a consequence of a primary developmental failure of the vermal primordium.
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Affiliation(s)
- Rosa Russo
- Department of Pathology, Hospital S. Giovanni di Dio, e Ruggi d'Aragona, Salerno, Italy.
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43
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Axes and gradients of the neural tube for a morphological/molecular genetic classification of nervous system malformations. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0072-9752(07)87001-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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44
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Disorders of segmentation of the neural tube: agenesis of selective neuromeres. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s0072-9752(07)87007-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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45
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Sarnat HB. Disorders of segmentation of the neural tube: Chiari malformations. HANDBOOK OF CLINICAL NEUROLOGY 2007; 87:89-103. [DOI: 10.1016/s0072-9752(07)87006-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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46
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Chemli J, Abroug M, Tlili K, Harbi A. Rhombencephalosynapsis diagnosed in childhood: clinical and MRI findings. Eur J Paediatr Neurol 2007; 11:35-8. [PMID: 17097321 DOI: 10.1016/j.ejpn.2006.09.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2006] [Revised: 09/18/2006] [Accepted: 09/23/2006] [Indexed: 11/23/2022]
Abstract
Rhombencephalosynapsis (RES) is a rare cerebellar malformation of unknown etiology characterized by vermal agenesis or hypogenesis, fusion of hemispheres and the dentate nuclei. Clinical presentation and prognosis are extremely variable and generally depends one the associated supratentorial anomalies. We report the first Tunisian case of RES diagnosed by magnetic resonance imaging (MRI) in a 3.5-year-old boy born to consanguineous parents. The child had spastic diplegia, facial dysmorphia, skeletal anomalies and normal intellectual development. Additional supratentorial anomalies were agenesis of septum pellucidum, moderate hydrocephalus and hypogenesis of corpus callosum. In this paper, the clinical and MRI findings and possible pathogenesis of this disorder are discussed.
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Affiliation(s)
- Jalel Chemli
- Department of Pediatrics, Sahloul Hospital, Sousse 4054, Tunisia.
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47
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Arenzana FJ, Carvan MJ, Aijón J, Sánchez-González R, Arévalo R, Porteros A. Teratogenic effects of ethanol exposure on zebrafish visual system development. Neurotoxicol Teratol 2006; 28:342-8. [PMID: 16574376 DOI: 10.1016/j.ntt.2006.02.001] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2005] [Revised: 01/31/2006] [Accepted: 02/03/2006] [Indexed: 11/17/2022]
Abstract
Ethanol intake during pregnancy can produce a wide range of adverse effects on nervous system development including fetal alcohol syndrome (FAS). The most severe congenital malformation observed in newborns with FAS is cyclopia. In this study, we have exposed zebrafish embryos to different ethanol concentrations (2.4%, 1.5% or 1.0%) during eye morphogenesis in four zebrafish strains (AB, EK, GL and TL). In addition, we have studied the survival rate of the cyclopic animals to the end of larval development. The zebrafish strains GL and AB generated the higher percentage of cyclopic animals after exposure to 2.4% ethanol, while EK showed the higher percent cyclopic animals using 1.5% and 1.0% ethanol. The EK strain showed the higher percent survival during the larval period at all ethanol concentrations (2.4%, 1.5% and 1.0%). Moreover, we have investigated cytoarchitectural alterations in the main components of the visual pathway-retina and optic tectum-and ethanol treatment affects both the retina and the optic tectum. The lamination of neural retina is clearly delayed in treated larvae 3 days postfertilization and the thickness of the pigmented epithelium is considerably reduced. With regard to the optic tectum, treatment with ethanol alters the normal pattern of tectal lamination. The use of zebrafish EK strain is a suitable in vivo vertebrate model system for analyzing the teratogenic effect of ethanol during vertebrate visual system morphogenesis as it relates to both cyclopia and FAS.
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Affiliation(s)
- F J Arenzana
- Dpto. de Biología Celular y Patología, Instituto de Neurociencias de Castilla y León, Universidad de Salamanca, E-37007 Salamanca, Spain
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48
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Abstract
Neural crest cells are first recognized at the lateral margin of the neural placode shortly after gastrulation, although they are not committed to their diverse fates until later. After dorsal closure of the neural tube, neural crest cells separate and migrate throughout the embryo to form many structures of ectodermal origin (eg, dorsal root and autonomic ganglia, peripheral nerve sheaths) and mesodermal origin (eg, blood vessels, melanocytes, adipose tissue, membranous bone, connective tissue, most of the ocular globe). Terminal differentiation occurs after migration is complete. Three regions of the neural tube generate neural crest: rhombencephalon, mesencephalon, and prosencephalon, each with a different migratory pattern. The most important genes promoting neural crest differentiation and migration are those with a dorsalizing influence in the vertical axis of the neural tube (eg, PAX3, BMP4, ZIC2), some segmentation genes (eg, WNT1), genes that inhibit neural crest (eg, EGR2), and neural crest-specific differentiating genes (eg, SLUG, SOX10). In the neurocutaneous syndromes, diverse features result from abnormal neural crest differentiation, providing a more encompassing embryologic basis for these disorders than the traditional view that these syndromes are somehow related to skin and brain because both are ectodermal derivatives. Abnormal angiogenesis, areas of abnormal pigmentation that sometimes follow the lines of Blashko, nerve sheath proliferations, disorders of chromaffin tissue, lipomes and benign and malignant tumors are frequent features. Many defective genes in neurocutaneous syndromes have an additional function as tumor suppressors. Interactions between genes associated with these disorders and others essential to neural crest formation, migration, and differentiation, are a likely molecular genetic basis for these diseases. The craniofacial abnormalities associated with many cerebral malformations and cutaneous lesions in some neurocutaneous syndromes emphasize an important inductive role of the neural tube in the development of non-neural tissues, mediated through neural crest.
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Affiliation(s)
- Harvey B Sarnat
- Department of Pediatrics (Neurology), University of Calgary, Faculty of Medicine, Alberta Children's Hospital, Calgary, AB, Canada.
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Curatolo P, Bombardieri R, Verdecchia M, Seri S. Intractable seizures in tuberous sclerosis complex: from molecular pathogenesis to the rationale for treatment. J Child Neurol 2005; 20:318-25. [PMID: 15921233 DOI: 10.1177/08830738050200040901] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Tuberous sclerosis complex is a multisystem autosomal dominant genetic disorder resulting from mutations in one of two genes, TSC1 and TSC2. Pathologically, tuberous sclerosis complex is characterized by abnormal cellular differentiation and proliferation, as well as abnormal neuronal migration. Epilepsy occurs in about 90% of patients, with onset frequently in the first year of life. In a sizable proportion of individuals, seizures tend to be refractory to antiepileptic drug treatment. This article reviews the progress in understanding drug-resistant seizures in tuberous sclerosis complex, from molecular pathogenesis to the pathophysiologic mechanisms of epileptogenesis, and the rationale for appropriate medical and surgical treatment.
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Affiliation(s)
- Paolo Curatolo
- Department of Neuroscience, Section of Pediatric Neurology, Tor Vergata University of Rome, Rome, Italy.
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50
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Sztriha L, Johansen JG, Al-Gazali LI. Extreme microcephaly with agyria-pachygyria, partial agenesis of the corpus callosum, and pontocerebellar dysplasia. J Child Neurol 2005; 20:170-2. [PMID: 15794192 DOI: 10.1177/08830738050200021301] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A 1-year-old boy with extreme microcephaly and a complex brain malformation is reported. Magnetic resonance imaging revealed an abnormal gyral pattern with features of the agyria-pachygyria spectrum, partial agenesis of the corpus callosum, severely hypoplastic posterior cerebellar vermis, and an abnormal foliation pattern of the cerebellar hemispheres associated with a flat and wide isthmus and pons. Although this phenotype shares some features with malformations classified as microcephaly with a simplified gyral pattern, microlissencephaly, or lissencephaly with cerebellar hypoplasia, none of the several subgroups of these categories are identical to the cerebral dysgenesis found in this patient.
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Affiliation(s)
- László Sztriha
- Department of Paediatrics, Faculty of Medicine and Health Sciences, United Arab Emirates University, Al Ain.
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