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AJNR. American Journal of Neuroradiology Jun 2009
Topics: Acrocallosal Syndrome; Adolescent; Adult; Aged; Brain Diseases; Cerebral Cortex; Choristoma; Diffusion Magnetic Resonance Imaging; Female; Humans; Image Processing, Computer-Assisted; Male; Middle Aged; Models, Neurological; Nerve Fibers, Myelinated; Neural Pathways; Young Adult
PubMed: 19369599
DOI: 10.3174/ajnr.A1521 -
Journal of Medical Genetics Aug 1990A boy presenting with an incomplete form of the acrocallosal syndrome is described. The syndrome shows clinical variability and it is stressed that none of the...
A boy presenting with an incomplete form of the acrocallosal syndrome is described. The syndrome shows clinical variability and it is stressed that none of the components is constant and facial dysmorphism is not always characteristic.
Topics: Abnormalities, Multiple; Agenesis of Corpus Callosum; Diagnosis, Differential; Facial Bones; Humans; Infant; Intellectual Disability; Male; Phenotype; Skull; Syndrome
PubMed: 2103730
DOI: 10.1136/jmg.27.8.516 -
Journal of Clinical and Experimental... Feb 2009After a review of Arthur Benton's conceptual and methodological contributions to the understanding of normal and pathological development, we discuss agenesis of the...
After a review of Arthur Benton's conceptual and methodological contributions to the understanding of normal and pathological development, we discuss agenesis of the corpus callosum (CC), criteria for potential neuroanatomical compensatory mechanisms in CC agenesis, and the results of an examination of magnetic resonance imaging (MRI) data of the CC in 193 children with spina bifida meningomyelocele (SBM). There were 26 CC regional patterns. Although complete agenesis did not occur, partial agenesis was observed in 102 children and within 15 CC regional patterns. Only 4.1% had a normal CC. Quantitative assessment of the area of the CC in 26 NC children and 68 children with SBM revealed that all subgroups with CC anomalies had smaller areas than did a subgroup with a normal CC. Areas were especially small in rostral/splenial agenesis and splenial agenesis but larger with rostral agenesis. Subgroups with normal/hypoplastic regions or complete hypoplasia also had CC areas that were smaller than normal but larger than the areas for the splenial agenesis groups. The relative rarity of anterior commissure enlargement (3.1%) and longitudinal bundles of Probst (0.1%) suggest that these particular fiber tract anomalies are unlikely candidates for structural compensatory mechanisms. The hippocampal commissure, enlarged in 13%, may be a more promising candidate. Overall, however, the functionality of anomalous fiber tracts and commissures in SBM is yet to be determined.
Topics: Acrocallosal Syndrome; Adolescent; Agenesis of Corpus Callosum; Brain Mapping; Child; Corpus Callosum; Female; Humans; Magnetic Resonance Imaging; Male; Meningomyelocele; Spinal Dysraphism
PubMed: 19052950
DOI: 10.1080/13803390802209954 -
PLoS Biology Oct 2009The corpus callosum (CC) is the main pathway responsible for interhemispheric communication. CC agenesis is associated with numerous human pathologies, suggesting that a...
The corpus callosum (CC) is the main pathway responsible for interhemispheric communication. CC agenesis is associated with numerous human pathologies, suggesting that a range of developmental defects can result in abnormalities in this structure. Midline glial cells are known to play a role in CC development, but we here show that two transient populations of midline neurons also make major contributions to the formation of this commissure. We report that these two neuronal populations enter the CC midline prior to the arrival of callosal pioneer axons. Using a combination of mutant analysis and in vitro assays, we demonstrate that CC neurons are necessary for normal callosal axon navigation. They exert an attractive influence on callosal axons, in part via Semaphorin 3C and its receptor Neuropilin-1. By revealing a novel and essential role for these neuronal populations in the pathfinding of a major cerebral commissure, our study brings new perspectives to pathophysiological mechanisms altering CC formation.
Topics: Acrocallosal Syndrome; Animals; Axons; Cell Line; Cell Movement; Coculture Techniques; Corpus Callosum; Humans; Mice; Neural Pathways; Neurons; Neuropilin-1; Semaphorins
PubMed: 19859539
DOI: 10.1371/journal.pbio.1000230 -
AJNR. American Journal of Neuroradiology Jun 2010There is gathering evidence to suggest that agenesis of the corpus callosum is associated with delayed fetal sulcation; it is possible that the corpus callosum...
BACKGROUND AND PURPOSE
There is gathering evidence to suggest that agenesis of the corpus callosum is associated with delayed fetal sulcation; it is possible that the corpus callosum facilitates normal gyral development. In this paper we sought to confirm whether delayed sulcation is found in fetuses with isolated agenesis of the corpus callosum as judged by in utero MR imaging.
MATERIALS AND METHODS
Retrospective analysis of 20 fetuses with isolated corpus callosum agenesis investigated by in utero MR imaging and 20 aged-matched normal fetuses was performed in the second or third trimester. All fetuses were singleton pregnancies with known gestational age, imaged on a 1.5T superconducting MR system. Estimation of sulcation maturity was made with reference to a standard atlas and subgroup analysis of earlier gestation (group 1, 21-26 weeks) and later gestation (group 2, 30-34 weeks) fetuses was performed.
RESULTS
Group 1 (n = 12) did not show a statistically significant difference between the 2 subgroups (P = .44) in terms of sulcation. A significant difference was demonstrated in the later gestation, group 2 (n = 8) fetal analyses; mean difference between consensus and actual gestation for normal fetuses was 0.9 weeks (SD of 1.5 weeks) versus -0.5 weeks (SD of 1.1 weeks) for the agenesis of corpus callosum cases (P = .046), suggestive of delayed sulcation in callosal agenesis.
CONCLUSIONS
Delayed sulcation encountered in third trimester fetuses with agenesis of the corpus callosum may be seen and does not in itself imply an additional brain abnormality.
Topics: Acrocallosal Syndrome; Agenesis of Corpus Callosum; Cell Movement; Cerebral Cortex; Female; Gestational Age; Humans; Magnetic Resonance Imaging; Malformations of Cortical Development; Nerve Fibers, Myelinated; Pregnancy; Pregnancy Trimester, Second; Pregnancy Trimester, Third; Prenatal Diagnosis; Retrospective Studies
PubMed: 20093312
DOI: 10.3174/ajnr.A1982 -
Psychiatria Danubina Jun 2010This article reports the case of a patient with partial agenesis of the corpus callosum manifested with corpus callosum syndrome together with signs of brain hemispheres...
This article reports the case of a patient with partial agenesis of the corpus callosum manifested with corpus callosum syndrome together with signs of brain hemispheres dysfunction: mental impairment, epilepsy and pyramidal signs. The patient's malformation is combined with left-handedness while signs of callosal disconnection are not present. Mild cognitive impairment and late epilepsy onset require a multidisciplinary approach since the patient also displays elements of central nervous system malformations.
Topics: Acrocallosal Syndrome; Adult; Amnesia; Anticonvulsants; Apraxias; Epilepsy, Generalized; Functional Laterality; Humans; Lamotrigine; Leg Length Inequality; Magnetic Resonance Imaging; Male; Neurologic Examination; Neuropsychological Tests; Paranoid Disorders; Pyramidal Tracts; Syndrome; Triazines
PubMed: 20562763
DOI: No ID Found -
Behavioral Neuroscience Oct 2009The nature and extent of deficiencies in bimanual motor coordination in individuals with agenesis of the corpus callosum (ACC) was studied using the computerized...
The nature and extent of deficiencies in bimanual motor coordination in individuals with agenesis of the corpus callosum (ACC) was studied using the computerized Bimanual Coordination Test (cBCT). Compared with previous bimanual tasks, the cBCT is more specifically reliant on interhemispheric interactions of lateralized motor control, allows more precise measurement, and permits examination of performance over a wider range of bimanual challenges. The cBCT performance of 13 high-functioning individuals with complete ACC was compared to 21 age- and IQ-matched controls. The groups did not differ in unimanual response speed. On trials involving angled paths that require bimanual coordination, the ACC group performed significantly slower and less accurately across all angles. The largest group differences in speed occurred on trials where the hands must respond symmetrically, while mirror-image (vs. parallel) responding produced the greatest deficits in accuracy. These data confirm previous findings of deficits in bimanual coordination in callosal absence, but using significantly improved measurement technology. Deficits in bimanual coordination in ACC are present across different demands for interhand interactions in the speed and direction of movement.
Topics: Acrocallosal Syndrome; Adolescent; Adult; Agenesis of Corpus Callosum; Analysis of Variance; Corpus Callosum; Female; Functional Laterality; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Motor Skills; Neuropsychological Tests; Orientation; Registries
PubMed: 19824766
DOI: 10.1037/a0016868 -
Journal of the International... Sep 2008Spina bifida meningomyelocele with hydrocephalus (SBM) is commonly associated with anomalies of the corpus callosum (CC). We describe MRI patterns of regional CC...
Spina bifida meningomyelocele with hydrocephalus (SBM) is commonly associated with anomalies of the corpus callosum (CC). We describe MRI patterns of regional CC agenesis and relate CC anomalies to functional laterality based on a dichotic listening test in 90 children with SBM and 27 typically developing controls. Many children with SBM (n = 40) showed regional CC anomalies in the form of agenesis of the rostrum and/or splenium, and a smaller number (n = 20) showed hypoplasia (thinning) of all CC regions (rostrum, genu, body, and splenium). The expected right ear advantage (REA) was exhibited by normal controls and children with SBM having a normal or hypoplastic splenium. It was not shown by children with SBM who were left handed, missing a splenium, or had a higher level spinal cord lesion. Perhaps the right hemisphere of these children is more involved in processing some aspects of linguistic stimuli.
Topics: Acoustic Stimulation; Acrocallosal Syndrome; Adolescent; Analysis of Variance; Auditory Perception; Child; Female; Functional Laterality; Humans; Magnetic Resonance Imaging; Male; Meningomyelocele; Prohibitins; Spinal Dysraphism; Transfer, Psychology
PubMed: 18764972
DOI: 10.1017/S1355617708080958 -
Neurology India 2011
Topics: Acrocallosal Syndrome; Adult; Agenesis of Corpus Callosum; Female; Humans; Hyperhidrosis; Hypothermia; Magnetic Resonance Imaging
PubMed: 21339684
DOI: 10.4103/0028-3886.76868 -
American Journal of Medical Genetics.... Jul 2009
Maternally inherited heterozygous sequence change in the sonic hedgehog gene in a male patient with bilateral closed-lip schizencephaly and partial absence of the corpus callosum.
Topics: Acrocallosal Syndrome; Hedgehog Proteins; Humans; Infant; Inheritance Patterns; Male; Malformations of Cortical Development; Mothers; Polymorphism, Genetic
PubMed: 19533790
DOI: 10.1002/ajmg.a.32940