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Lo J, Cardinell J, Costanzo A, Sussman D. Medical Augmentation (Med-Aug) for Optimal Data Augmentation in Medical Deep Learning Networks. SENSORS (BASEL, SWITZERLAND) 2021; 21:7018. [PMID: 34770324 PMCID: PMC8587013 DOI: 10.3390/s21217018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 10/11/2021] [Accepted: 10/18/2021] [Indexed: 11/16/2022]
Abstract
Deep learning (DL) algorithms have become an increasingly popular choice for image classification and segmentation tasks; however, their range of applications can be limited. Their limitation stems from them requiring ample data to achieve high performance and adequate generalizability. In the case of clinical imaging data, images are not always available in large quantities. This issue can be alleviated by using data augmentation (DA) techniques. The choice of DA is important because poor selection can possibly hinder the performance of a DL algorithm. We propose a DA policy search algorithm that offers an extended set of transformations that accommodate the variations in biomedical imaging datasets. The algorithm makes use of the efficient and high-dimensional optimizer Bi-Population Covariance Matrix Adaptation Evolution Strategy (BIPOP-CMA-ES) and returns an optimal DA policy based on any input imaging dataset and a DL algorithm. Our proposed algorithm, Medical Augmentation (Med-Aug), can be implemented by other researchers in related medical DL applications to improve their model's performance. Furthermore, we present our found optimal DA policies for a variety of medical datasets and popular segmentation networks for other researchers to use in related tasks.
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Affiliation(s)
- Justin Lo
- Electrical, Computer and Biomedical Engineering, Ryerson University, Toronto, ON M5B 2K3, Canada; (J.L.); (J.C.); (A.C.)
- Institute for Biomedical Engineering, Science and Technology (iBEST) at Ryerson University & St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada
| | - Jillian Cardinell
- Electrical, Computer and Biomedical Engineering, Ryerson University, Toronto, ON M5B 2K3, Canada; (J.L.); (J.C.); (A.C.)
- Institute for Biomedical Engineering, Science and Technology (iBEST) at Ryerson University & St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada
| | - Alejo Costanzo
- Electrical, Computer and Biomedical Engineering, Ryerson University, Toronto, ON M5B 2K3, Canada; (J.L.); (J.C.); (A.C.)
- Institute for Biomedical Engineering, Science and Technology (iBEST) at Ryerson University & St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada
| | - Dafna Sussman
- Electrical, Computer and Biomedical Engineering, Ryerson University, Toronto, ON M5B 2K3, Canada; (J.L.); (J.C.); (A.C.)
- Institute for Biomedical Engineering, Science and Technology (iBEST) at Ryerson University & St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada
- The Keenan Research Centre for Biomedical Science, St. Michael’s Hospital, Toronto, ON M5B 1T8, Canada
- Department of Obstetrics and Gynecology, Faculty of Medicine, University of Toronto, Toronto, ON M5G 1E2, Canada
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2
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Alexander RG, Yazdanie F, Waite S, Chaudhry ZA, Kolla S, Macknik SL, Martinez-Conde S. Visual Illusions in Radiology: Untrue Perceptions in Medical Images and Their Implications for Diagnostic Accuracy. Front Neurosci 2021; 15:629469. [PMID: 34177444 PMCID: PMC8226024 DOI: 10.3389/fnins.2021.629469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 04/19/2021] [Indexed: 11/13/2022] Open
Abstract
Errors in radiologic interpretation are largely the result of failures of perception. This remains true despite the increasing use of computer-aided detection and diagnosis. We surveyed the literature on visual illusions during the viewing of radiologic images. Misperception of anatomical structures is a potential cause of error that can lead to patient harm if disease is seen when none is present. However, visual illusions can also help enhance the ability of radiologists to detect and characterize abnormalities. Indeed, radiologists have learned to exploit certain perceptual biases in diagnostic findings and as training tools. We propose that further detailed study of radiologic illusions would help clarify the mechanisms underlying radiologic performance and provide additional heuristics to improve radiologist training and reduce medical error.
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Affiliation(s)
- Robert G Alexander
- Department of Ophthalmology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States.,Department of Neurology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States.,Department of Physiology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
| | - Fahd Yazdanie
- Department of Radiology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
| | - Stephen Waite
- Department of Radiology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
| | - Zeshan A Chaudhry
- Department of Radiology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
| | - Srinivas Kolla
- Department of Radiology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
| | - Stephen L Macknik
- Department of Ophthalmology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States.,Department of Neurology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States.,Department of Physiology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
| | - Susana Martinez-Conde
- Department of Ophthalmology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States.,Department of Neurology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States.,Department of Physiology and Pharmacology, State University of New York Downstate Health Sciences University, Brooklyn, NY, United States
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3
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Prenatal Ultrasonographic Molar Tooth Sign: Case Reports and Review of Literature. JOURNAL OF FETAL MEDICINE 2021. [DOI: 10.1007/s40556-021-00291-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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4
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Singh J, Dalal P, Rattan K. Development delay in a child with microcephaly and birth asphyxia: Explore diagnosis beyond hypotonic cerebral palsy. J Pediatr Neurosci 2021; 16:285-288. [DOI: 10.4103/jpn.jpn_126_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 07/04/2020] [Indexed: 11/06/2022] Open
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5
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Mckinnon K, Kendall GS, Tann CJ, Dyet L, Sokolska M, Baruteau KP, Marlow N, Robertson NJ, Peebles D, Srinivasan L. Biometric assessments of the posterior fossa by fetal MRI: A systematic review. Prenat Diagn 2020; 41:258-270. [PMID: 33251640 DOI: 10.1002/pd.5874] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 10/07/2020] [Accepted: 11/19/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND Posterior fossa abnormalities (PFAs) are commonly identified within routine screening and are a frequent indication for fetal magnetic resonance imaging (MRI). Although biometric measurements of the posterior fossa (PF) are established on fetal ultrasound and MRI, qualitative visual assessments are predominantly used to differentiate PFAs. OBJECTIVES This systematic review aimed to assess 2-dimensional (2D) biometric measurements currently in use for assessing the PF on fetal MRI to delineate different PFAs. METHODS The protocol was registered (PROSPERO ID CRD42019142162). Eligible studies included T2-weighted MRI PF measurements in fetuses with and without PFAs, including measurements of the PF, or other brain areas relevant to PFAs. RESULTS 59 studies were included - 6859 fetuses had 62 2D PF and related measurements. These included linear, area and angular measurements, representing measures of PF size, cerebellum/vermis, brainstem, and supratentorial measurements. 11 measurements were used in 10 or more studies and at least 1200 fetuses. These dimensions were used to characterise normal for gestational age, diagnose a range of pathologies, and predict outcome. CONCLUSION A selection of validated 2D biometric measurements of the PF on fetal MRI may be useful for identification of PFA in different clinical settings. Consistent use of these measures, both clinically and for research, is recommended.
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Affiliation(s)
- Katie Mckinnon
- Neonatal Department, University College London Hospitals NHS Foundation Trust, London, UK.,Institute for Women's Health, University College London, London, UK
| | - Giles S Kendall
- Neonatal Department, University College London Hospitals NHS Foundation Trust, London, UK.,Institute for Women's Health, University College London, London, UK
| | - Cally J Tann
- Neonatal Department, University College London Hospitals NHS Foundation Trust, London, UK.,MARCH Centre, London School of Hygiene and Tropical Medicine, London, UK
| | - Leigh Dyet
- Neonatal Department, University College London Hospitals NHS Foundation Trust, London, UK.,Institute for Women's Health, University College London, London, UK
| | - Magdalena Sokolska
- Institute for Women's Health, University College London, London, UK.,Medical Physics Department, University College London Hospitals NHS Foundation Trust, London, UK
| | - Kelly Pegoretti Baruteau
- Institute for Women's Health, University College London, London, UK.,Radiology Department, University College London Hospitals NHS Foundation Trust, London, UK
| | - Neil Marlow
- Neonatal Department, University College London Hospitals NHS Foundation Trust, London, UK.,Institute for Women's Health, University College London, London, UK
| | - Nicola J Robertson
- Neonatal Department, University College London Hospitals NHS Foundation Trust, London, UK.,Institute for Women's Health, University College London, London, UK
| | - Donald Peebles
- Institute for Women's Health, University College London, London, UK.,Obstetric Department, University College London Hospitals NHS Foundation Trust, London, UK
| | - Latha Srinivasan
- Neonatal Department, University College London Hospitals NHS Foundation Trust, London, UK.,Institute for Women's Health, University College London, London, UK
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Imaging phenotype correlation with molecular and molecular pathway defects in malformations of cortical development. Pediatr Radiol 2020; 50:1974-1987. [PMID: 33252763 DOI: 10.1007/s00247-020-04674-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/23/2020] [Accepted: 03/31/2020] [Indexed: 10/22/2022]
Abstract
The increase in understanding of molecular biology and recent advances in genetic testing have caused rapid growth in knowledge of genetic causes of malformations of cortical development. Imaging diagnosis of malformations of cortical development can be made prenatally in a large subset of fetuses based on the presence of specific deviations from the normal pattern of development, characteristic imaging features, and associated non-central-nervous-system (CNS) abnormalities. In this review the authors discuss the role of four key cell molecules/molecular pathways in corticogenesis that are frequently implicated in complex prenatally diagnosed malformations of cortical development. The authors also list the currently described genes causing defects in these molecules/molecular pathways when mutated, and the constellation of imaging findings resultant of such defects.
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7
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Bachmann-Gagescu R, Dempsey JC, Bulgheroni S, Chen ML, D'Arrigo S, Glass IA, Heller T, Héon E, Hildebrandt F, Joshi N, Knutzen D, Kroes HY, Mack SH, Nuovo S, Parisi MA, Snow J, Summers AC, Symons JM, Zein WM, Boltshauser E, Sayer JA, Gunay-Aygun M, Valente EM, Doherty D. Healthcare recommendations for Joubert syndrome. Am J Med Genet A 2019; 182:229-249. [PMID: 31710777 DOI: 10.1002/ajmg.a.61399] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/02/2019] [Accepted: 10/09/2019] [Indexed: 12/19/2022]
Abstract
Joubert syndrome (JS) is a recessive neurodevelopmental disorder defined by a characteristic cerebellar and brainstem malformation recognizable on axial brain magnetic resonance imaging as the "Molar Tooth Sign". Although defined by the neurological features, JS is associated with clinical features affecting many other organ systems, particularly progressive involvement of the retina, kidney, and liver. JS is a rare condition; therefore, many affected individuals may not have easy access to subspecialty providers familiar with JS (e.g., geneticists, neurologists, developmental pediatricians, ophthalmologists, nephrologists, hepatologists, psychiatrists, therapists, and educators). Expert recommendations can enable practitioners of all types to provide quality care to individuals with JS and know when to refer for subspecialty care. This need will only increase as precision treatments targeting specific genetic causes of JS emerge. The goal of these recommendations is to provide a resource for general practitioners, subspecialists, and families to maximize the health of individuals with JS throughout the lifespan.
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Affiliation(s)
- Ruxandra Bachmann-Gagescu
- Institute of Molecular Life Sciences, University of Zurich, Zurich, Switzerland.,Institute of Medical Genetics, University of Zurich, Schlieren, Switzerland
| | - Jennifer C Dempsey
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington
| | - Sara Bulgheroni
- Developmental Neurology Division, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Maida L Chen
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington.,Division of Pulmonary and Sleep Medicine, Seattle Children's Hospital, Seattle, Washington
| | - Stefano D'Arrigo
- Developmental Neurology Division, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Ian A Glass
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington
| | - Theo Heller
- Liver Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Elise Héon
- Department of Surgery, Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Ophthalmology and Vision Science, University of Toronto, Toronto, Ontario, Canada
| | - Friedhelm Hildebrandt
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts.,Division of Nephrology, Boston Children's Hospital, Boston, Massachusetts
| | - Nirmal Joshi
- Department of Anesthesia, Deaconess Hospital, Evansville, Indiana.,Anesthesia Dynamics, LLC, Evansville, Indiana
| | - Dana Knutzen
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas.,The Children's Hospital of San Antonio, San Antonio, Texas
| | - Hester Y Kroes
- Department of Medical Genetics, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Stephen H Mack
- Joubert Syndrome and Related Disorders Foundation, Petaluma, California
| | - Sara Nuovo
- Neurogenetics Lab, IRCCS Santa Lucia Foundation, Rome, Italy.,Department of Medicine and Surgery, University of Salerno, Salerno, Italy
| | - Melissa A Parisi
- Intellectual and Developmental Disabilities Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland
| | - Joseph Snow
- Office of the Clinical Director, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland
| | - Angela C Summers
- Office of the Clinical Director, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland.,Department of Psychology, Fordham University, Bronx, New York
| | - Jordan M Symons
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington.,Division of Nephrology, Seattle Children's Hospital, Seattle, Washington
| | - Wadih M Zein
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland
| | - Eugen Boltshauser
- Department of Pediatric Neurology (emeritus), Children's University Hospital, Zürich, Switzerland
| | - John A Sayer
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, UK.,Renal Services, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK.,NIHR Newcastle Biomedical Research Centre, Newcastle upon Tyne, UK
| | - Meral Gunay-Aygun
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland.,Department of Pediatrics and McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Enza Maria Valente
- Neurogenetics Lab, IRCCS Santa Lucia Foundation, Rome, Italy.,Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Dan Doherty
- Department of Pediatrics, University of Washington School of Medicine, Seattle, Washington.,Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
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8
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Sun L, Guo C, Yao L, Zhang T, Wang J, Wang L, Liu Y, Wang K, Wang L, Wu Q. Quantitative diagnostic advantages of three-dimensional ultrasound volume imaging for fetal posterior fossa anomalies: Preliminary establishment of a prediction model. Prenat Diagn 2019; 39:1086-1095. [PMID: 31441071 DOI: 10.1002/pd.5549] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Revised: 08/12/2019] [Accepted: 08/13/2019] [Indexed: 12/14/2022]
Abstract
OBJECTIVES To quantitatively assess prenatal diagnostic performance of three-dimensional ultrasound (3D-US) for posterior fossa anomalies (PFA) and establish a preliminarily 3D-US prediction model. METHODS Sixty singleton fetuses suspected of PFA by 2D-US presented their detailed 3D-US evaluation. The surface area of vermis (SAV), brainstem-vermis, and brainstem-tentorium angles were measured by 3D-US. The good prognosis was defined as normal neurodevelopmental outcome. MRI and autopsy were the diagnostic reference standard. RESULTS There was a significant difference between 2D-US (60.0%, 36/60) and 3D-US (94.8%, 55/58) for the diagnostic accuracy (P < .01). Prenatal 3D-US prediction model was established with observed/expected SAV as the main predictor (area under the curve [AUC]: 0.901; 95% CI, 0.810-0.992, P < .001). When it was more than 107.5%, the prognosis seemed to be good (sensitivity: 96.4%, specificity: 26.7%), which led to consideration of mega cisterna magna, Blake pouch cyst, or small arachnoid cyst. The prognosis appeared to be poor when it was less than 73% (sensitivity: 71.4%, specificity: 100%), and the diagnosis tended to be a Dandy-Walker malformation, vermian hypoplasia, and cerebellar hypoplasia. Brainstem-vermis and brainstem-tentorium angles were the secondary indicators (AUC: 0.689 vs 0.761; 95% CI, 0.541-0.836 vs 0.624-0.897, P = .014 vs.001). CONCLUSIONS It seems that the exact types of PFA can be effectively diagnosed by quantitative indicators of 3D-US.
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Affiliation(s)
- Lijuan Sun
- Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Cuixia Guo
- Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Ling Yao
- Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Tiejuan Zhang
- Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Jingjing Wang
- Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Li Wang
- Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Yan Liu
- Department of Obstetrics, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Keyang Wang
- Department of Radiology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
| | - Longxia Wang
- Department of Ultrasound, the General Hospital of the People's Liberation Army, Beijing, China
| | - Qingqing Wu
- Department of Ultrasound, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing, China
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9
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Prenatal Diagnosis and Genetic Analysis of a Fetus with Joubert Syndrome. BIOMED RESEARCH INTERNATIONAL 2018; 2018:7202168. [PMID: 29955609 PMCID: PMC6000882 DOI: 10.1155/2018/7202168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 05/06/2018] [Indexed: 12/31/2022]
Abstract
Objective To diagnose and explore the genetic cause of Joubert syndrome (JS) in a fetus. Methods Prenatal ultrasound and magnetic resonance imaging (MRI) examinations were performed, and genetic analysis was conducted using targeted next-generation sequencing (NGS) and Sanger sequencing. Results Prenatal ultrasound and MRI examinations showed cerebellar vermis hypoplasia and molar tooth sign (MTS); hence the fetus was diagnosed with JS. Further genetic analysis revealed a known missense variant (c.3599C>T, p.A1200V) and a novel missense variant (c.3857G>A, p.R1286H) in the C5orf42 gene of the fetus. Conclusion Our study provides insights into prenatal and early diagnosis of JS and expands the variation spectrum of C5orf42 gene.
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10
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Llorens Salvador R, Viegas Sainz A, Montoya Filardi A, Montoliu Fornas G, Menor Serrano F. Evaluation of the fetal cerebellum by magnetic resonance imaging. RADIOLOGIA 2017. [DOI: 10.1016/j.rxeng.2017.08.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Llorens Salvador R, Viegas Sainz A, Montoya Filardi A, Montoliu Fornas G, Menor Serrano F. Evaluation of the fetal cerebellum by magnetic resonance imaging. RADIOLOGIA 2017; 59:380-390. [PMID: 28735870 DOI: 10.1016/j.rx.2017.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 06/16/2017] [Accepted: 06/20/2017] [Indexed: 11/30/2022]
Abstract
Obstetric protocols dictate that the fetal cerebellum should always be assessed during sonograms during pregnancy. For various reasons, including technical limitations or inconclusive sonographic findings, suspicion of cerebellar abnormalities is one of the most common indications for prenatal magnetic resonance imaging (MRI). Although sonography is the imaging technique of choice to assess the cerebellum, MRI shows the anatomy of the posterior fossa and abnormalities in the development of the fetal cerebellum in greater detail and thus enables a more accurate prenatal diagnosis. We describe and illustrate the normal anatomy of the fetal cerebellum on MRI as well as the different diseases that can affect its development. Moreover, we review the most appropriate terminology to define developmental abnormalities, their differential diagnoses, and the role of MRI in the prenatal evaluation of the posterior fossa.
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Affiliation(s)
- R Llorens Salvador
- Área de Imagen Médica, Sección de Imagen Pediátrica, Hospital Universitario y Politécnico La Fe, Valencia, España.
| | - A Viegas Sainz
- Servicio de Obstetricia y Ginecología, Hospital Lluís Alcanyís, Xàtiva, Valencia
| | - A Montoya Filardi
- Área de Imagen Médica, Sección de Imagen Pediátrica, Hospital Universitario y Politécnico La Fe, Valencia, España
| | - G Montoliu Fornas
- Área de Imagen Médica, Sección de Imagen Pediátrica, Hospital Universitario y Politécnico La Fe, Valencia, España
| | - F Menor Serrano
- Área de Imagen Médica, Sección de Imagen Pediátrica, Hospital Universitario y Politécnico La Fe, Valencia, España
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12
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Said AH, El-Kattan E, Abdel-Hakeem AK, Saleem S. In utero MRI diagnosis of fetal malformations in oligohydramnios pregnancies. THE EGYPTIAN JOURNAL OF RADIOLOGY AND NUCLEAR MEDICINE 2016. [DOI: 10.1016/j.ejrnm.2016.06.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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13
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Abstract
The human cerebellum has a protracted development that makes it vulnerable to a broad spectrum of developmental disorders including malformations and disruptions. Starting from 19 to 20 weeks of gestation, prenatal magnetic resonance imaging (MRI) can reliably study the developing cerebellum. Pre- and postnatal neuroimaging plays a key role in the diagnostic work-up of congenital cerebellar abnormalities. Diagnostic criteria for cerebellar malformations and disruptions are based mostly on neuroimaging findings. The diagnosis of a Dandy-Walker malformation is based on the presence of hypoplasia, elevation, and counterclockwise upward rotation of the cerebellar vermis and cystic dilatation of the fourth ventricle, which extends posteriorly filling out the posterior fossa. For the diagnosis of Joubert syndrome, the presence of the molar tooth sign (thickened, elongated, and horizontally orientated superior cerebellar peduncles and an abnormally deep interpeduncular fossa) is needed. The diagnostic criteria of rhombencephalosynapsis include a complete or partial absence of the cerebellar vermis and continuity of the cerebellar hemispheres across the midline. Unilateral cerebellar hypoplasia is defined by the complete aplasia or hypoplasia of one cerebellar hemisphere. Familiarity with these diagnostic criteria as well as the broad spectrum of additional neuroimaging findings is important for a correct pre- and postnatal diagnosis. A correct diagnosis is essential for management, prognosis, and counseling of the affected children and their family.
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14
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Abstract
Ultrasound and magnetic resonance imaging are the two imaging modalities used in the assessment of the fetus. Ultrasound is the primary imaging modality, whereas magnetic resonance is used in cases of diagnostic uncertainty. Both techniques have advantages and disadvantages and therefore they are complementary. Standard axial ultrasound views of the posterior fossa are used for routine scanning for fetal anomalies, with additional orthogonal views directly and indirectly obtainable using three-dimensional ultrasound techniques. Magnetic resonance imaging allows not only direct orthogonal imaging planes, but also tissue characterization, for example to search for blood breakdown products. We review the nomenclature of several posterior fossa anomalies using standardized criteria, and we review cerebellar abnormalities based on an etiologic classification.
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15
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Bin Dahman HA, Bin Mubaireek AHM, Alhaddad ZH. Joubert syndrome in a neonate: case report with literature review. Sudan J Paediatr 2016; 16:53-57. [PMID: 27651554 PMCID: PMC5025933] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Joubert syndrome is a rare autosomal recessive disorder. It is characterized by congenital ataxia, hypotonia, developmental delay and at least one of the following features: neonatal respiratory disturbances and abnormal eye movements; including nystagmus and oculomotor apraxia. Molar tooth appearance is an essential finding for the diagnosis of Joubert syndrome. We report a five-days-old newborn with mild hypotonia, abnormal pattern of respiration, abnormal eye movements and molar tooth sign on brain CT scan. Joubert syndrome is an uncommon inherited condition and delayed diagnosis is usually related to its variable, non-specific presentation. Awareness of the characteristic clinical and radiological findings in Joubert syndrome will help in early diagnosis, appropriate counseling and proper rehabilitation.
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Affiliation(s)
- Haifa A Bin Dahman
- Hadhramout University College of Medicine, Hadhramout Governorate, Yemen
| | | | - Zain H Alhaddad
- Surgical Department, Radiology Division, Hadhramout University College of Medicine, Hadhramout Governorate, Yemen
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16
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Conte G, Parazzini C, Falanga G, Cesaretti C, Izzo G, Rustico M, Righini A. Diagnostic Value of Prenatal MR Imaging in the Detection of Brain Malformations in Fetuses before the 26th Week of Gestational Age. AJNR Am J Neuroradiol 2015; 37:946-51. [PMID: 26721771 DOI: 10.3174/ajnr.a4639] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 11/05/2015] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE In several countries, laws and regulations allow abortion for medical reasons within 24-25 weeks of gestational age. We investigated the diagnostic value of prenatal MR imaging for brain malformations within 25 weeks of gestational age. MATERIALS AND METHODS We retrospectively included fetuses within 25 weeks of gestational age who had undergone both prenatal and postnatal MR imaging of the brain between 2002 and 2014. Two senior pediatric neuroradiologists evaluated prenatal MR imaging examinations blinded to postnatal MR imaging findings. With postnatal MR imaging used as the reference standard, we calculated the sensitivity, specificity, positive predictive value, and negative predictive value of the prenatal MR imaging in detecting brain malformations. RESULTS One-hundred nine fetuses (median gestational age at prenatal MR imaging: 22 weeks; range, 21-25 weeks) were included in this study. According to the reference standard, 111 malformations were detected. Prenatal MR imaging failed to detect correctly 11 of the 111 malformations: 3 midline malformations, 5 disorders of cortical development, 2 posterior fossa anomalies, and 1 vascular malformation. Prenatal MR imaging misdiagnosed 3 findings as pathologic in the posterior fossa. CONCLUSIONS The diagnostic value of prenatal MR imaging between 21 and 25 weeks' gestational age is very high, with limitations of sensitivity regarding the detection of disorders of cortical development.
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Affiliation(s)
- G Conte
- From the Departments of Radiology and Neuroradiology (G.C., C.P., C.C., G.I., A.R.) Department of Health Sciences (G.C.), University of Milan, Milan, Italy
| | - C Parazzini
- From the Departments of Radiology and Neuroradiology (G.C., C.P., C.C., G.I., A.R.)
| | - G Falanga
- Department of Biopathology and Medical and Forensic Biotechnologies (G.F.), Section of Radiological Sciences, University of Palermo, Palermo, Italy
| | - C Cesaretti
- From the Departments of Radiology and Neuroradiology (G.C., C.P., C.C., G.I., A.R.)
| | - G Izzo
- From the Departments of Radiology and Neuroradiology (G.C., C.P., C.C., G.I., A.R.)
| | - M Rustico
- Gynecology and Obstetrics (M.R.), Children's Hospital Vittore Buzzi, Milan, Italy
| | - A Righini
- From the Departments of Radiology and Neuroradiology (G.C., C.P., C.C., G.I., A.R.)
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17
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Kasprian GJ, Paldino MJ, Mehollin-Ray AR, Shetty A, Williams JL, Lee W, Cassady CI. Prenatal imaging of occipital encephaloceles. Fetal Diagn Ther 2014; 37:241-8. [PMID: 25358260 DOI: 10.1159/000366159] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 07/25/2014] [Indexed: 11/19/2022]
Abstract
INTRODUCTION This retrospective study aims to describe systematically the fetal cerebral MR morphology in cases with occipital meningoencephaloceles using standard and advanced fetal MRI techniques. MATERIAL AND METHODS The 1.5-tesla MR examinations (T1- and T2-weighted imaging, echo planar imaging, EPI, diffusion-weighted imaging, DWI) of 14 fetuses with occipital/parietal meningoencephaloceles were retrospectively analyzed for the classification of anatomic characteristics. A diffusion tensor sequence was performed in 5 cases. RESULTS In 9/14 cases the occipital lobes were entirely or partially included in the encephalocele sac. Typical features of Chiari III malformation were seen in 6/14 cases. The displaced brain appeared grossly disorganized in 6/14. The brainstem displayed abnormal 'kinking'/rotation (3/14), a z-shape (1/14) and/or a molar tooth-like configuration of the midbrain (3/14). Tractography revealed the presence and position of sensorimotor tracts in 5/5 and the corpus callosum in 3/5. DWI was helpful in the identification of a displaced brain (in 8/9). EPI visualized the anatomy of draining cerebral veins in 7/9 cases. Clinical (9/14) and MRI (7/14) follow-up data are presented. DISCUSSION Encephaloceles show a wide range of morphological heterogeneity. Fetal MRI serves as an accurate tool in the visualization of brainstem, white matter pathway and cerebral venous involvement and facilitates the detection of specific underlying syndromes such as ciliopathies.
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Affiliation(s)
- Gregor J Kasprian
- Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria
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18
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Chapman T, Mahalingam S, Ishak GE, Nixon JN, Siebert J, Dighe MK. Diagnostic imaging of posterior fossa anomalies in the fetus and neonate: part 2, Posterior fossa disorders. Clin Imaging 2014; 39:167-75. [PMID: 25457569 DOI: 10.1016/j.clinimag.2014.10.012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 10/16/2014] [Accepted: 10/20/2014] [Indexed: 01/15/2023]
Abstract
This second portion of a two-part review illustrates examples of posterior fossa disorders detectable on prenatal ultrasound and MRI, with postnatal or pathology correlation where available. These disorders are discussed in the context of an anatomic classification scheme described in Part 1 of this posterior fossa anomaly review. Assessment of the size and formation of the cerebellar hemispheres and vermis is critical. Diagnoses discussed here include arachnoid cyst, Blake's pouch cyst, Dandy-Walker malformation, vermian agenesis, Joubert syndrome, rhombencephalosynapsis, Chiari II malformation, ischemia, and tumors.
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Affiliation(s)
- Teresa Chapman
- Department of Radiology, Seattle Children's Hospital, MA.7.220, 4800 Sand Point Way NE, Seattle, WA, 98105; Department of Radiology, University of Washington Medical Center, Box 357115, 1959 NE Pacific Street, Seattle, WA 98195-7117.
| | - Sowmya Mahalingam
- Department of Radiology, University of Washington Medical Center, Box 357115, 1959 NE Pacific Street, Seattle, WA 98195-7117
| | - Gisele E Ishak
- Department of Radiology, Seattle Children's Hospital, MA.7.220, 4800 Sand Point Way NE, Seattle, WA, 98105; Department of Radiology, University of Washington Medical Center, Box 357115, 1959 NE Pacific Street, Seattle, WA 98195-7117
| | - Jason N Nixon
- Department of Radiology, Seattle Children's Hospital, MA.7.220, 4800 Sand Point Way NE, Seattle, WA, 98105; Department of Radiology, University of Washington Medical Center, Box 357115, 1959 NE Pacific Street, Seattle, WA 98195-7117
| | - Joseph Siebert
- Department of Pathology, Seattle Children's Hospital, PC.8.720, 4800 Sand Point Way NE, Seattle, WA, 98105
| | - Manjiri K Dighe
- Department of Radiology, University of Washington Medical Center, Box 357115, 1959 NE Pacific Street, Seattle, WA 98195-7117
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19
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Quarello E, Molho M, Garel C, Couture A, Legac MP, Moutard ML, Bault JP, Fallet-Bianco C, Guibaud L. Prenatal abnormal features of the fourth ventricle in Joubert syndrome and related disorders. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2014; 43:227-232. [PMID: 23868831 DOI: 10.1002/uog.12567] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 06/27/2013] [Accepted: 07/11/2013] [Indexed: 06/02/2023]
Abstract
Joubert syndrome and related disorders (JSRD) are characterized by absence or underdevelopment of the cerebellar vermis and a malformed brainstem. This family of disorders is a member of an emerging class of diseases called ciliopathies. We describe the abnormal features of the brain, particularly the fourth ventricle, in seven fetuses affected by JSRD. In three cases abnormality of the fourth ventricle was isolated and in four cases there were associated malformations. The molar tooth sign (MTS) was always present and visible on two-dimensional ultrasound and, when performed, on three-dimensional ultrasound and magnetic resonance imaging. The fourth ventricle was always abnormal, in both axial and sagittal views, presenting pathognomonic deformities. It is important to identify JSRD, preferably prenatally or at least postnatally, due to its high risk of recurrence of about 25%. A detailed prenatal assessment of the fourth ventricle in several views may help to achieve this goal.
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Affiliation(s)
- E Quarello
- Unité d'Échographies Obstétricales, Service de Gynécologie Obstétrique, Pôle Parents Enfants, Hôpital Saint-Joseph, Marseille, France; Institut de Médecine de la Reproduction, Marseille, France
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20
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Abstract
Joubert syndrome is a congenital cerebellar ataxia with autosomal recessive or X-linked inheritance, the diagnostic hallmark of which is a unique cerebellar and brainstem malformation recognisable on brain imaging-the so-called molar tooth sign. Neurological signs are present from the neonatal period and include hypotonia progressing to ataxia, global developmental delay, ocular motor apraxia, and breathing dysregulation. These signs are variably associated with multiorgan involvement, mainly of the retina, kidneys, skeleton, and liver. 21 causative genes have been identified so far, all of which encode for proteins of the primary cilium or its apparatus. The primary cilium is a subcellular organelle that has key roles in development and in many cellular functions, making Joubert syndrome part of the expanding family of ciliopathies. Notable clinical and genetic overlap exists between distinct ciliopathies, which can co-occur even within families. Such variability is probably explained by an oligogenic model of inheritance, in which the interplay of mutations, rare variants, and polymorphisms at distinct loci modulate the expressivity of the ciliary phenotype.
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21
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Saleem SN. Fetal magnetic resonance imaging (MRI): a tool for a better understanding of normal and abnormal brain development. J Child Neurol 2013; 28:890-908. [PMID: 23644716 DOI: 10.1177/0883073813486296] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Knowledge of the anatomy of the developing fetal brain is essential to detect abnormalities and understand their pathogenesis. Capability of magnetic resonance imaging (MRI) to visualize the brain in utero and to differentiate between its various tissues makes fetal MRI a potential diagnostic and research tool for the developing brain. This article provides an approach to understand the normal and abnormal brain development through schematic interpretation of fetal brain MR images. MRI is a potential screening tool in the second trimester of pregnancies in fetuses at risk for brain anomalies and helps in describing new brain syndromes with in utero presentation. Accurate interpretation of fetal MRI can provide valuable information that helps genetic counseling, facilitates management decisions, and guides therapy. Fetal MRI can help in better understanding the pathogenesis of fetal brain malformations and can support research that could lead to disease-specific interventions.
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Affiliation(s)
- Sahar N Saleem
- Department of Radiology, Kasr Al Ainy Faculty of Medicine, Cairo University, Cairo, Egypt.
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22
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Saleem SN. Fetal MRI: An approach to practice: A review. J Adv Res 2013; 5:507-23. [PMID: 25685519 PMCID: PMC4294280 DOI: 10.1016/j.jare.2013.06.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 06/03/2013] [Accepted: 06/04/2013] [Indexed: 11/25/2022] Open
Abstract
MRI has been increasingly used for detailed visualization of the fetus in utero as well as pregnancy structures. Yet, the familiarity of radiologists and clinicians with fetal MRI is still limited. This article provides a practical approach to fetal MR imaging. Fetal MRI is an interactive scanning of the moving fetus owed to the use of fast sequences. Single-shot fast spin-echo (SSFSE) T2-weighted imaging is a standard sequence. T1-weighted sequences are primarily used to demonstrate fat, calcification and hemorrhage. Balanced steady-state free-precession (SSFP), are beneficial in demonstrating fetal structures as the heart and vessels. Diffusion weighted imaging (DWI), MR spectroscopy (MRS), and diffusion tensor imaging (DTI) have potential applications in fetal imaging. Knowing the developing fetal MR anatomy is essential to detect abnormalities. MR evaluation of the developing fetal brain should include recognition of the multilayered-appearance of the cerebral parenchyma, knowledge of the timing of sulci appearance, myelination and changes in ventricular size. With advanced gestation, fetal organs as lungs and kidneys show significant changes in volume and T2-signal. Through a systematic approach, the normal anatomy of the developing fetus is shown to contrast with a wide spectrum of fetal disorders. The abnormalities displayed are graded in severity from simple common lesions to more complex rare cases. Complete fetal MRI is fulfilled by careful evaluation of the placenta, umbilical cord and amniotic cavity. Accurate interpretation of fetal MRI can provide valuable information that helps prenatal counseling, facilitate management decisions, guide therapy, and support research studies.
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Affiliation(s)
- Sahar N Saleem
- Department of Radiology, Kasr Al Ainy Faculty of Medicine, Cairo University, Cairo, Egypt
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23
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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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Abdel-Salam GMH, Abdel-Hamid MS, Saleem SN, Ahmed MKH, Issa M, Effat LK, Kayed HF, Zaki MS, Gaber KR. Profound microcephaly, primordial dwarfism with developmental brain malformations: a new syndrome. Am J Med Genet A 2012; 158A:1823-31. [PMID: 22786707 DOI: 10.1002/ajmg.a.35480] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 04/23/2012] [Indexed: 11/09/2022]
Abstract
We describe two sibs with a lethal form of profound congenital microcephaly, intrauterine and postnatal growth retardation, subtle skeletal changes, and poorly developed brain. The sibs had striking absent cranial vault with sloping of the forehead, large beaked nose, relatively large ears, and mandibular micro-retrognathia. Brain magnetic resonance imaging (MRI) revealed extremely simplified gyral pattern, large interhemispheric cyst and agenesis of corpus callosum, abnormally shaped hippocampus, and proportionately affected cerebellum and brainstem. In addition, fundus examination showed foveal hypoplasia with optic nerve atrophy. No abnormalities of the internal organs were found. This profound form of microcephaly was identified at 17 weeks gestation by ultrasound and fetal brain MRI helped in characterizing the developmental brain malformations in the second sib. Molecular analysis excluded mutations in potentially related genes such as RNU4ATAC, SLC25A19, and ASPM. These clinical and imaging findings are unlike that of any recognized severe forms of microcephaly which is believed to be a new microcephalic primordial dwarfism (MPD) with developmental brain malformations with most probably autosomal recessive inheritance based on consanguinity and similarly affected male and female sibs.
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Affiliation(s)
- Ghada M H Abdel-Salam
- Division of Human Genetics and Genome Research, Department of Clinical Genetics, National Research Centre, Cairo, Egypt.
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25
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Joubert syndrome: brain and spinal cord malformations in genotyped cases and implications for neurodevelopmental functions of primary cilia. Acta Neuropathol 2012; 123:695-709. [PMID: 22331178 DOI: 10.1007/s00401-012-0951-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 01/25/2012] [Accepted: 01/27/2012] [Indexed: 12/12/2022]
Abstract
Joubert syndrome (JS) is an autosomal recessive ciliopathy characterized by hypotonia, ataxia, abnormal eye movements, and intellectual disability. The brain is malformed, with severe vermian hypoplasia, fourth ventriculomegaly, and "molar tooth" appearance of the cerebral and superior cerebellar peduncles visible as consistent features on neuroimaging. Neuropathological studies, though few, suggest that several other brain and spinal cord structures, such as the dorsal cervicomedullary junction, may also be affected in at least some patients. Genetically, JS is heterogeneous, with mutations in 13 genes accounting for approximately 50% of patients. Here, we compare neuropathologic findings in five subjects with JS, including four with defined mutations in OFD1 (2 siblings), RPGRIP1L, or TCTN2. Characteristic findings in all JS genotypes included vermian hypoplasia, fragmented dentate and spinal trigeminal nuclei, hypoplastic pontine and inferior olivary nuclei, and nondecussation of corticospinal tracts. Other common findings, seen in multiple genotypes but not all subjects, were dorsal cervicomedullary heterotopia, nondecussation of superior cerebellar peduncles, enlarged arcuate nuclei, hypoplastic reticular formation, hypoplastic medial lemnisci, and dorsal spinal cord disorganization. Thus, while JS exhibits significant neuropathologic as well as genetic heterogeneity, no genotype-phenotype correlations are apparent as yet. Our findings suggest that primary cilia are important for neural patterning, progenitor proliferation, cell migration, and axon guidance in the developing human brain and spinal cord.
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Burguete Moriones A, Cabada Giadás T, Bacaicoa Saralegui M, Annicherico Sánchez F. Síndrome de Joubert: hallazgos en resonancia magnética convencional y tensor de difusión. RADIOLOGIA 2012; 54:279-82. [DOI: 10.1016/j.rx.2010.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 09/24/2010] [Accepted: 09/27/2010] [Indexed: 11/28/2022]
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27
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Zaki MS, Salam GMHA, Saleem SN, Dobyns WB, Issa MY, Sattar S, Gleeson JG. New recessive syndrome of microcephaly, cerebellar hypoplasia, and congenital heart conduction defect. Am J Med Genet A 2011; 155A:3035-41. [PMID: 22002884 PMCID: PMC3415795 DOI: 10.1002/ajmg.a.34078] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2010] [Accepted: 04/06/2011] [Indexed: 11/11/2022]
Abstract
We identified a two-branch consanguineous family in which four affected members (three females and one male) presented with constitutive growth delay, severe psychomotor retardation, microcephaly, cerebellar hypoplasia, and second-degree heart block. They also shared distinct facial features and similar appearance of their hands and feet. Childhood-onset insulin-dependent diabetes mellitus developed in one affected child around the age of 9 years. Molecular analysis excluded mutations in potentially related genes such as PTF1A, EIF2AK3, EOMES, and WDR62. This condition appears to be unique of other known conditions, suggesting a unique clinical entity of autosomal recessive mode of inheritance. © 2011 Wiley Periodicals, Inc.
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Affiliation(s)
- Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo, Egypt.
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28
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Sattar S, Gleeson JG. The ciliopathies in neuronal development: a clinical approach to investigation of Joubert syndrome and Joubert syndrome-related disorders. Dev Med Child Neurol 2011; 53:793-798. [PMID: 21679365 PMCID: PMC3984879 DOI: 10.1111/j.1469-8749.2011.04021.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A group of disorders with disparate symptomatology, including congenital cerebellar ataxia, retinal blindness, liver fibrosis, polycystic kidney disease, and polydactyly, have recently been united under a single disease mechanism called 'ciliopathies'. The ciliopathies are due to defects of the cellular antenna known as the primary cilium, a microtubule-based extension of cellular membranes found in nearly all cell types. Key among these ciliopathies is Joubert syndrome, displaying ataxia, oculomotor apraxia, and mental retardation* with a pathognomonic 'molar tooth sign' on brain magnetic resonance imaging. The importance of ciliary function in neuronal development has been appreciated only in the last decade with the classification of Joubert syndrome as a ciliopathy. This, together with the identification of many of the clinical features of ciliopathies in individuals with Joubert syndrome and the localization of Joubert syndrome's causative gene products at or near the primary cilium, have defined a new class of neurological disease. Cilia are involved in diverse cellular processes including protein trafficking, photoreception, embryonic axis patterning, and cell cycle regulation. Ciliary dysfunction can affect a single tissue or manifest as multi-organ involvement. Ciliary defects have been described in retinopathies such as retinitis pigmentosa and Leber congenital amaurosis (defects in photoreceptor ciliary protein complexes), renal syndromes with nephronophthisis and cystic dysplastic kidneys, and liver conditions such as fibrosis and biliary cirrhosis. Recognizing the diverse presentations of the ciliopathies and screening strategies following diagnosis is an important part of the treatment plan of children with cilia-related disorders.
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Affiliation(s)
- Shifteh Sattar
- Department of Neurosciences and Paediatrics, University of California, San Diego, La Jolla, CA, USA
| | - Joseph G Gleeson
- Department of Neurosciences and Paediatrics, University of California, San Diego, La Jolla, CA, USA
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Defective Wnt-dependent cerebellar midline fusion in a mouse model of Joubert syndrome. Nat Med 2011; 17:726-31. [PMID: 21623382 PMCID: PMC3110639 DOI: 10.1038/nm.2380] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 04/19/2011] [Indexed: 01/15/2023]
Abstract
The ciliopathy Joubert syndrome is marked by cerebellar vermis hypoplasia, a phenotype for which the pathogenic mechanism is unclear1–3. In order to investigate Joubert syndrome pathogenesis, we have examined mice with mutated Ahi1, the first identified Joubert syndrome gene4,5. These mice exhibit cerebellar hypoplasia with a vermis/midline fusion defect early in development. This defect is concomitant with expansion of the roof plate and is also evident in a mouse mutant for another Joubert syndrome gene, Cep2906,7. Further, fetal magnetic resonance imaging (MRI) from human subjects with Joubert syndrome reveals a similar midline cleft suggesting parallel pathogenic mechanisms. Previous evidence has suggested a role for Jouberin (Jbn), the protein encoded by Ahi1, in canonical Wnt signaling8. Consistent with this, we found decreased Wnt reporter activity at the site of hemisphere fusion in the developing cerebellum of Ahi1 mutant mice. This decrease was accompanied by reduced proliferation at the site of fusion. Finally, treatment with lithium, a Wnt pathway agonist9, partially rescued this phenotype. Our findings implicate a defect in Wnt signaling in the cerebellar midline phenotype seen in Joubert syndrome, which can be overcome with Wnt stimulation.
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Brancati F, Dallapiccola B, Valente EM. Joubert Syndrome and related disorders. Orphanet J Rare Dis 2010; 5:20. [PMID: 20615230 PMCID: PMC2913941 DOI: 10.1186/1750-1172-5-20] [Citation(s) in RCA: 241] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2009] [Accepted: 07/08/2010] [Indexed: 12/22/2022] Open
Abstract
Joubert syndrome (JS) and related disorders (JSRD) are a group of developmental delay/multiple congenital anomalies syndromes in which the obligatory hallmark is the molar tooth sign (MTS), a complex midbrain-hindbrain malformation visible on brain imaging, first recognized in JS. Estimates of the incidence of JSRD range between 1/80,000 and 1/100,000 live births, although these figures may represent an underestimate. The neurological features of JSRD include hypotonia, ataxia, developmental delay, intellectual disability, abnormal eye movements, and neonatal breathing dysregulation. These may be associated with multiorgan involvement, mainly retinal dystrophy, nephronophthisis, hepatic fibrosis and polydactyly, with both inter- and intra-familial variability. JSRD are classified in six phenotypic subgroups: Pure JS; JS with ocular defect; JS with renal defect; JS with oculorenal defects; JS with hepatic defect; JS with orofaciodigital defects. With the exception of rare X-linked recessive cases, JSRD follow autosomal recessive inheritance and are genetically heterogeneous. Ten causative genes have been identified to date, all encoding for proteins of the primary cilium or the centrosome, making JSRD part of an expanding group of diseases called "ciliopathies". Mutational analysis of causative genes is available in few laboratories worldwide on a diagnostic or research basis. Differential diagnosis must consider in particular the other ciliopathies (such as nephronophthisis and Senior-Loken syndrome), distinct cerebellar and brainstem congenital defects and disorders with cerebro-oculo-renal manifestations. Recurrence risk is 25% in most families, although X-linked inheritance should also be considered. The identification of the molecular defect in couples at risk allows early prenatal genetic testing, whereas fetal brain neuroimaging may remain uninformative until the end of the second trimester of pregnancy. Detection of the MTS should be followed by a diagnostic protocol to assess multiorgan involvement. Optimal management requires a multidisciplinary approach, with particular attention to respiratory and feeding problems in neonates and infants. Cognitive and behavioral assessments are also recommended to provide young patients with adequate neuropsychological support and rehabilitation. After the first months of life, global prognosis varies considerably among JSRD subgroups, depending on the extent and severity of organ involvement.
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Affiliation(s)
- Francesco Brancati
- Mendel Laboratory, Casa Sollievo della Sofferenza Hospital, IRCCS, San Giovanni Rotondo, Italy
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Chen CP, Su YN, Huang JK, Liu YP, Tsai FJ, Yang CK, Huang JP, Chen CY, Wu PC, Wang W. Fetal Magnetic Resonance Imaging Demonstration Of Central Nervous System Abnormalities and Polydactyly Associated With Joubert Syndrome. Taiwan J Obstet Gynecol 2010; 49:243-6. [DOI: 10.1016/s1028-4559(10)60055-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/27/2010] [Indexed: 11/24/2022] Open
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