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1/25. Can early postnatal closed head injury induce cortical dysplasia.

    PURPOSE: Increased availability of surgically resected epileptogenic tissues reveals often unsuspected cortical dysplasia (CD). There is some controversy about the ontogenic stages in which these occur. Although most take place during neuroblast proliferation and migration, there is some evidence for some CD occurring during postmigrational intrinsic cortical organization. It has been shown that various kinds of focal cortical manipulations in rats, if performed within 3-4 postnatal days, lead to the genesis of various cortical malformations including a four-layered microgyrus or an unlayered CD. It is not known whether such events also might occur in the human brain. methods: Two children sustained minor head trauma within 4 postnatal days and later developed intractable epilepsy, which was relieved by surgery. Neuropathologic analysis of the resected tissues revealed an unsuspected microdysplastic cortex immediately adjacent to a focal, modest meningeal fibrosis, presumably secondary to the old closed head trauma. RESULTS: The main histologic features were a disorganized, unlayered cortex; abnormal clusters of neurons, often with complex, randomly oriented proximal dendritic patterns with absent apical orientation; the presence of a number of heterotopic small and large neurons in the white matter; absence of inflammatory infiltrates, of hemosiderine, of reactive gliosis, or of an excessive number of blood vessels. The morphologic features in these surgical specimens suggest that these focal malformations occur because of a regional disorder of postmigrational intrinsic cortical remodeling. CONCLUSIONS: The clinical histories and the pathologic findings lend some support to the hypothesis that minor morbid events occuring in the immediate postnatal period may lead to microdysplasia in the human similar to those induced in rat pups. The animal model could be helpful to clarify the genesis of some cases of CD and of the epileptogenicity often manifesting later in life.
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keywords = cortex
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2/25. Bilateral frontoparietal polymicrogyria and epilepsy.

    Two patients with bilateral frontoparietal polymicrogyria are reported. Severe developmental delay, mental retardation, spastic tetraplegia, and seizures were the main clinical features. magnetic resonance imaging revealed a bilateral thick cortex with irregular gyri and a festoonlike gray-white matter junction. Bilateral frontoparietal polymicrogyria may represent a further form of the bilateral polymicrogyria syndromes in addition to perisylvian and parasagittal parieto-occipital polymicrogyria.
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ranking = 0.5
keywords = cortex
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3/25. Ophthalmic manifestations of neonatal onset multisystem inflammatory disease.

    PURPOSE: To report the ophthalmic manifestations of neonatal onset multisystem inflammatory disease, a recently recognized, rare systemic disorder characterized by the triad of arthropathy, rash, and abnormal central nervous system development. METHOD: Case report. RESULTS: A 2-year-old female with neonatal onset multisystem inflammatory disease presented with visual acuity of fix and follow with each eye, bilateral optic nerve head pallor and gliosis, as well as marked sheathing of the peripapillary vessels. No vitreous inflammation or macular edema was found. visual acuity was stable from the neonatal period through the 3 months of follow-up after the changes involving the optic nerve heads and peripapillary vessels were observed (a total of 33 months). CONCLUSIONS: This report provides a description of the ocular manifestations of neonatal onset multisystem inflammatory disease and supports earlier suggestions that swelling of the optic nerve heads can occur. In this case, optic nerve head pallor may have been a sequela of such swelling. The pathogenesis of neonatal onset multisystem inflammatory disease is unknown.
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keywords = visual
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4/25. Effect of multiple subpial transection on motor cortical excitability in cortical dysgenesis.

    We report here a 12-year-old patient with unilateral cortical dysgenesis and intractable simple partial seizure in his left arm, who underwent multiple subpial transection (MST) in the right cerebral cortex including the primary motor cortex. We investigated motor cortical excitability using multimodal transcranial magnetic stimulation (TMS) before and 1 month after MST, in which surgical cortical incisions were made with strokes 5 mm apart and 4 mm deep. Preoperative TMS studies showed hyperexcitability in the affected motor cortex as abnormally prolonged muscle responses to TMS with a wide cortical motor map, which were markedly reduced following the operation. The preoperative motor evoked potentials were large and polyphasic, and consisted of early and late components. The late component was completely abolished after MST, suggesting that this component might be due to activation of the corticospinal tract neurones by long recurrent axon branches of dysplastic excitatory pyramidal neurones, which were cut by MST, or by delayed, polysynaptic intracortical conduction with marked temporal dispersion. Intracortical inhibition in the affected motor cortex was also disrupted preoperatively and improved after MST. Postoperative recruitment order of muscle responses to TMS was bilaterally symmetrical, indicating that MST did not interfere with the function of the corticospinal tract neurones. The patient showed fair motor recovery and good seizure control after the operation. These results of TMS studies demonstrated the remarkable effectiveness of MST not only on intractable seizure but also on abnormal motor cortical organization and hyperexcitability in cortical dysgenesis.
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keywords = cortex
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5/25. Neuropsychological profile of a 9-year-old child with subcortical band heterotopia or 'double cortex'.

    Subcortical band heterotopia (SBH) or 'double cortex', is a congenital brain abnormality that results from aberrant migration of neurons during development of the cortex. MRI shows a continuous band of heterotopic grey matter located between the cortex and ventricular walls, separated from them by a thin layer of white matter. The condition is quite rare, found predominantly in females, and is occasionally familial with an X-linked dominant inheritance. Current research has focused on genetic and neurological correlates, with cognitive assessment restricted to a global measure of general intellectual functioning. This paper describes in detail the results of a neuropsychological assessment of a 9-year-old female recently diagnosed with SBH. Predominant features were a significantly reduced speed of processing for visuomotor and oral output and reduced immediate registration of information. This difficulty has functional implications affecting skill acquisition, learning in the classroom, and social interaction.
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ranking = 3.5
keywords = cortex
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6/25. Surgical resection for intractable epilepsy in "double cortex" syndrome yields inadequate results.

    PURPOSE: To analyze the results of surgical treatment of intractable epilepsy in patients with subcortical band heterotopia, or double cortex syndrome, a diffuse neuronal migration disorder. methods: We studied eight patients (five women) with double cortex syndrome and intractable epilepsy. All had a comprehensive presurgical evaluation including prolonged video-EEG recordings and magnetic resonance imaging (MRI). RESULTS: All patients had partial seizures, with secondary generalization in six of them. neurologic examination was normal in all. Three were of normal intelligence, and five were mildly retarded. Six patients underwent invasive EEG recordings, three of them with subdural grids and three with stereotactic implanted depth electrodes (SEEG). Although EEG recordings showed multilobar epileptic abnormalities in most patients, regional or focal seizure onset was recorded in all. MRI showed bilateral subcortical band heterotopia, asymmetric in thickness in three. An additional area of cortical thickening in the left frontal lobe was found in one patient. Surgical procedures included multiple subpial transections in two patients, frontal lesionectomy in one, temporal lobectomy with amygdalohippocampectomy in five, and an additional anterior callosotomy in one. Five patients had no significant improvement, two had some improvement, and one was greatly improved. CONCLUSION: Our results do not support focal surgical removal of epileptogenic tissue in patients with double cortex syndrome, even in the presence of a relatively localized epileptogenic area.
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ranking = 3.5
keywords = cortex
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7/25. autopsy case of thanatophoric dysplasia: observations on the serial sections of the brain.

    The neuropathological findings in an autopsy case of thanatophoric dysplasia (TD) with serial sections of the brain are described here. This patient was a female infant, born at 33 weeks gestation, who died on day 1. Skeletal anomalies, consisting of short limbs, a small thorax, short ribs, thick cortical vertebral body substance and sternum substance, and hypoplastic lungs, were compatible with typical phenotypic features of TD. The brain weighed 370 g, showing a cloverleaf megalencephaly. A computerized 3-D reconstruction technique visualized clearly abnormal deep sulci arranged perpendicular to the neuraxis on the inferior surface of the temporal lobe, and peculiar configurational changes of the lateral ventricle. In particular, the inferior horn showed an unusual complex form. Dysgenetic changes were largely located in the anterior temporal lobe as follows: cortical polymicrogyria; leptomeningeal heterotopia with discontinuity of the subpial basement membrane; serpentine arrangement of pyramidal cells of the cornu ammonis (CA)1 of the hippocampus; hypoplastic dentate gyrus; hyperplasia of the amygdaloid body; and heterotopic nodules of neuroblasts or glioblasts in the periventricular white matter. Apart from the temporal lobe, the cerebral pia mater showed unusual fusion of two facing sheets in a sulcus and ectopia of nerve cells, and the cerebellar vermis was small. The findings observed here indicate that overgrowth and lack of growth can coexist in the TD brain, suggesting that some interaction(s) between the mesenchyme and the nervous tissue may play a role in normal differentiation of these two cell lines.
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ranking = 0.0043909783309547
keywords = visual
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8/25. Functional activation of microgyric visual cortex in a human.

    We report on the case of a 20-year-old man with bilateral parasagittal parieto-occipital polymicrogyria and epilepsy. Functional magnetic resonance imaging responses to reversing checkerboard and interhemispheric electroencephalogram coherence changes to moving gratings were investigated. Results of both studies indicate that the polymicrogyric cortex was activated by visual stimuli, suggesting preserved function in the dysplastic area.
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ranking = 2.5219548916548
keywords = cortex, visual
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9/25. Agenesis of the mesencephalon and metencephalon with cerebellar hypoplasia: putative mutation in the EN2 gene--report of 2 cases in early infancy.

    Congenital absence of the midbrain and upper pons is a rare human malformation. We describe two unrelated infants with this anomaly and cerebellar hypoplasia who were born at term but died in early infancy from lack of central respiratory drive. MRI in both cases disclosed the lesions during life. Neuropathological examination, performed in one, included immunocytochemical studies of NeuN, synaptophysin, vimentin, and glial fibrillary acidic protein (GFAP). autopsy revealed a thin midline cord passing through the clivus, in place of the midbrain; it corresponded to hypoplastic and fused corticospinal tracts with ectopic neural tissue in the surrounding leptomeninges. Some ectopia were immunoreactive for synaptophysin and NeuN and others were nonreactive. The neural surfaces facing the subarachnoid fluid-filled space left by the absent midbrain and upper pons were lined by an abnormal villous ependyma. The architecture of the cerebellar cortex was imperfect but generally normal, and Bergmann glial cells had normal radial processes shown by vimentin and GFAP. Structures of the telencephalon, diencephalon, lower brainstem, and spinal cord were generally well formed, but inferior olivary and dentate nuclei were rudimentary and the spinal central canal was dilated at lumbar levels. The cerebral cortex was normally laminated, but pyramidal neurons of layer 5 were sparse in the frontal lobes. The hippocampus, olfactory system, and corpus callosum were formed. An ectopic lingual thyroid was found and had been associated with hypothyroidism during life. A murine model resembling this dysgenesis is demonstrated by homozygous mutations of the organizer genes Wnt1 or En1, also resulting in cerebellar aplasia, and En2, associated with cerebellar hypoplasia. These genes are essential to the formation of the mesencephalic neuromere and rhombomere 1 (metencephalon or upper pons and cerebellum). Pax8 has binding sites in the promoter for En2 and is essential for thyroid development. We speculate that in the human, the failure to form a mesencephalon and metencephalon, with cerebellar hypoplasia, results from a mutation or deletion in the EN2 (Engrailed-2) gene.
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ranking = 1
keywords = cortex
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10/25. Neurological manifestations of the oculodentodigital dysplasia syndrome.

    Oculodentodigital dysplasia (ODDD) (MIM 164200) is a rare autosomal dominant inherited disorder affecting the development of the face, eyes, limbs and dentition. Neurological complications are thought to be occasional manifestations of the disorder. This report illustrates the neurological manifestations by a pedigree of two ODDD patients with spastic paraparesis, cerebral white matter hyperintensity and basal ganglia hypointensity. A systematic review of the English, French, German and Italian literature on ODDD is also provided to summarize the neurological manifestations of the disorder. 243 previously described ODDD cases presented a spectrum of neurological manifestation including spasticity (25), subcortical white matter lesions (9) and basal ganglia changes (6) on MRI. Additional findings consisted of gaze palsy and squinting (28), bladder and bowel disturbances (21), visual loss (20) and blindness (4), hearing loss (15), ataxia (11), nystagmus (9), muscle weakness (5) and paresthesias (3). Neurological manifestations, including spasticity associated with MRI changes, are an underrecognized feature in the ODDD phenotype. A clinical guide to the neurological manifestations of ODDD may assist in the assessment of patients with this condition.
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ranking = 0.0043909783309547
keywords = visual
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