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1.
AJNR Am J Neuroradiol ; 29(2): 301-5, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17974614

RESUMEN

BACKGROUND AND PURPOSE: Hypomyelination and congenital cataract (HCC) is an autosomal recessive white matter disease caused by deficiency of hyccin, a membrane protein implicated in both central and peripheral myelination. We aimed to describe the neuroimaging features of this novel entity. MATERIALS AND METHODS: A systematic analysis of patients with unclassified leukoencephalopathies admitted to our institutions revealed 10 children with congenital cataract, slowly progressive neurologic impairment, and diffuse white matter abnormalities on neuroimaging. Psychomotor developmental delay was evident after the first year of life. Peripheral neuropathy was demonstrated by neurophysiologic studies in 9 children. The available neuroimaging studies were retrospectively reviewed. RESULTS: In all patients, neuroimaging revealed diffuse involvement of the supratentorial white matter associated with preservation of both cortical and deep gray matter structures. Supratentorial white matter hypomyelination was detected in all patients; 7 patients also had evidence of variably extensive areas of increased white matter water content. Deep cerebellar white matter hypomyelination was found in 6 patients. Older patients had evidence of white matter bulk loss and gliosis. Proton MR spectroscopy showed variable findings, depending on the stage of the disease. Sural nerve biopsy revealed hypomyelinated nerve fibers. Mutations in the DRCTNNB1A gene on chromosome 7p15.3, causing complete or severe deficiency of hyccin, were demonstrated in all patients. CONCLUSIONS: HCC is characterized by a combined pattern of primary myelin deficiency and secondary neurodegenerative changes. In the proper clinical setting, recognition of suggestive neuroimaging findings should prompt appropriate genetic investigations.


Asunto(s)
Encéfalo/patología , Catarata/congénito , Catarata/diagnóstico , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/congénito , Enfermedades Desmielinizantes del Sistema Nervioso Central Hereditarias/diagnóstico , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Fibras Nerviosas Mielínicas/patología , Estudios Retrospectivos , Síndrome
2.
Neuropediatrics ; 36(4): 265-9, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16138252

RESUMEN

Hypomyelinating leukoencephalopathies may be related to a primary disturbance in the formation of myelin or may be caused by neuronal, oligodendrocytic or astrocytic dysfunction, leading to a failure of myelination. Abnormal myelination related to a direct metabolic damage on oligodendrocytes has been shown to occur in some animal models of lysosomal storage diseases. To demonstrate that cerebral white matter hypomyelination may occur also in humans affected by early-onset lysosomal storage diseases, we report three cases with infantile-onset lysosomal storage disorders (type 1 GM1 gangliosidosis, globoid cell leukodystrophy or Krabbe's disease, and type A Niemann-Pick disease) showing white matter hypomyelination. Hypomyelinating leukoencephalopathy may therefore represent a feature of lysosomal storage disorders with onset in the first months of life, when the process of myelination is particularly active, indicating that neuronal storage disorders may be primarily responsible for central nervous system hypomyelination.


Asunto(s)
Enfermedades Desmielinizantes/etiología , Leucodistrofia Metacromática/etiología , Enfermedades por Almacenamiento Lisosomal/complicaciones , Edad de Inicio , Enfermedades Desmielinizantes/patología , Femenino , Gangliosidosis GM1/metabolismo , Humanos , Lactante , Leucodistrofia Metacromática/metabolismo , Leucodistrofia Metacromática/patología , Enfermedades por Almacenamiento Lisosomal/patología , Imagen por Resonancia Magnética/métodos , Masculino
5.
J Neuroradiol ; 31(1): 3-24, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15026728

RESUMEN

Spinal cord development occurs through the three consecutive periods of gastrulation (weeks 2-3), primary neurulation (weeks 3-4), and secondary neurulation (weeks 5-6). Spinal cord malformations derive from defects in these early embryonic stages, and are collectively called spinal dysraphisms. Spinal dysraphisms may be categorized clinically into open and closed, based on whether the abnormal nervous tissue is exposed to the environment or covered by skin. Open spinal dysraphisms include myelomeningocele and other rare abnormalities such as myelocele, hemimyelomeningocele, and hemimyelocele, and are always associated with a Chiari II malformation. Closed spinal dysraphisms are further divided into two subsets based on whether a subcutaneous mass is present in the low back. Closed spinal dysraphisms with mass comprise lipomyelocele, lipomyelomeningocele, meningocele, and myelocystocele. Closed spinal dysraphisms without mass comprise simple dysraphic states (tight filum terminale, filar and intradural lipomas, persistent terminal ventricle, and dermal sinuses) and complex dysraphic states. The latter category involves abnormal notochordal development, either in the form of failed midline integration (ranging from complete dorsal enteric fistula to neurenteric cysts and diastematomyelia) or of segmental agenesis (caudal agenesis and spinal segmental dysgenesis). Magnetic resonance imaging is the imaging modality of choice for evaluation of this complex group of disorders.


Asunto(s)
Malformación de Arnold-Chiari/diagnóstico , Imagen por Resonancia Magnética , Disrafia Espinal/diagnóstico , Adolescente , Malformación de Arnold-Chiari/clasificación , Malformación de Arnold-Chiari/embriología , Encéfalo/embriología , Encéfalo/patología , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Embarazo , Médula Espinal/embriología , Médula Espinal/patología , Disrafia Espinal/clasificación , Disrafia Espinal/embriología
7.
Top Magn Reson Imaging ; 12(6): 375-409, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11744877

RESUMEN

Spinal cord development occurs through three consecutive periods. Gastrulation (weeks 2-3) is characterized by conversion of the embryonic disk from a bilaminar to a trilaminar arrangement and establishment of a notochord. Primary neurulation (weeks 3-4) produces the uppermost nine tenths of the spinal cord. Secondary neurulation and retrogressive differentiation (weeks 5-6) result in formation of the conus tip and filum terminale. Defects in these early embryonic stages produce spinal dysraphisms, which are characterized by anomalous differentiation and fusion of dorsal midline structures. Spinal dysraphisms may be categorized clinically into two subsets. In open spinal dysraphisms, the placode (non-neurulated neural tissue) is exposed to the environment. These disorders include myelomeningocele, myeloschisis, hemimyelomeningocele, and hemimyelocele, and are always associated with a Chiari II malformation. Closed spinal dysraphisms are covered by intact skin, although cutaneous stigmata usually indicate their presence. Two subsets may be identified based on whether a subcutaneous mass is present in the low back. Closed spinal dysraphisms with mass comprise lipomyeloschisis, lipomyelomeningocele, meningocele, and myelocystocele. Closed spinal dysraphisms without mass comprise complex dysraphic states (ranging from complete dorsal enteric fistula to neurenteric cysts, split cord malformations, dermal sinuses, caudal regression, and spinal segmental dysgenesis), bony spina bifida, tight filum terminale, filar and intradural lipomas, and persistent terminal ventricle. Magnetic resonance imaging is the imaging method of choice for investigation of this complex group of disorders.


Asunto(s)
Imagen por Resonancia Magnética , Disrafia Espinal/diagnóstico , Adolescente , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Disrafia Espinal/clasificación , Disrafia Espinal/embriología
8.
AJNR Am J Neuroradiol ; 22(3): 554-63, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11237984

RESUMEN

BACKGROUND AND PURPOSE: Combined methylmalonic aciduria and homocystinuria (MMA-HC) is caused by impaired hepatic conversion of dietary cobalamin to methylcobalamin and adenosylcobalamin, resulting in decreased activity of methylmalonyl-CoA mutase and methionine synthase. Patients with the early-onset variety present within 12 months of age with severe neurologic, hematologic, and gastrointestinal abnormalities. We describe the neuroradiologic features of early-onset MMA-HC and discuss related pathophysiological mechanisms. METHODS: Twelve infants with hypotonia, failure to thrive, poor feeding, and hematologic abnormalities were diagnosed with MMA-HC on the basis of a typical plasmatic and urinary metabolic profile and enzyme activity in fibroblastic cultures. Complementation studies were performed in two cases, and yielded a CblC result. MR imaging was performed at presentation in four cases and later in the others. All patients showed prompt biochemical improvement with intramuscular hydroxocobalamin administration, and most had moderate neurologic improvement. RESULTS: Diffuse supratentorial white matter edema and dysmyelination was the typical MR picture at presentation, whereas white matter bulk loss characterized later stages of the disease. Nucleocapsular areas of gliosis were an additional finding in one case. One patient had tetraventricular hydrocephalus at presentation. CONCLUSION: White matter damage is probably caused by reduced methyl group availability and nonphysiological fatty acids toxicity, whereas focal gliosis results from homocysteine-induced toxicity to the endothelium. Hydrocephalus may result from diffuse intracranial extracerebral arterial stiffness, known as reduced arterial pulsation hydrocephalus. MR imaging features at presentation and at follow-up are nonspecific.


Asunto(s)
Encéfalo/patología , Homocistinuria/diagnóstico , Homocistinuria/orina , Imagen por Resonancia Magnética , Ácido Metilmalónico/orina , Tomografía Computarizada por Rayos X , Edema Encefálico/complicaciones , Edema Encefálico/diagnóstico , Enfermedades Desmielinizantes/complicaciones , Enfermedades Desmielinizantes/diagnóstico , Femenino , Gliosis/complicaciones , Gliosis/diagnóstico , Homocistinuria/complicaciones , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos
11.
Neuroradiology ; 43(11): 934-40, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11760796

RESUMEN

We report on the neuroradiological studies performed on three infants with capillary haemangioma (CH) of the head and neck with associated posterior fossa and arterial abnormalities. Posterior fossa malformations were represented by cerebellar hemispheric and vermian hypoplasia and cerebellar cortical dysgenesis, whereas arterial anomalies included bilateral agenesis, kinking, and looping of the internal carotid arteries. One patient had marked exophthalmos due to intraorbital CH. We suggest that these patients had an incomplete phenotypic expression of PHACES syndrome, a vascular phakomatosis characterised by the variable association of posterior fossa malformations, CH, arterial anomalies, coarctation of the aorta and cardiac defects, eye abnormalities, and sternal and medioventral defects. Evidence suggests that PHACES syndrome is not a random association but a true phakomatosis; further studies are awaited to shed light on a possible genetic background. The phenotypic spectrum is broad and still largely unexplored, and precise diagnostic criteria have not yet been identified. A causal teratogenic influence, possibly related to anomalous expression of vascular growth factors and their modulators, is suggested to occur between gestational weeks 3 and 5.5


Asunto(s)
Arteria Carótida Interna/anomalías , Fosa Craneal Posterior/anomalías , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/patología , Hemangioma Capilar/diagnóstico por imagen , Hemangioma Capilar/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/patología , Fosa Craneal Posterior/diagnóstico por imagen , Fosa Craneal Posterior/patología , Femenino , Hemangioma Capilar/complicaciones , Humanos , Lactante , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética , Masculino , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
12.
Neuroradiology ; 42(7): 471-91, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10952179

RESUMEN

Our purpose was to review the neuroradiological features of spinal dysraphism and to correlate them with clinical findings and up-to-date embryological theory. We also aimed to formulate a working classification which might prove useful in clinical practice. We reviewed series of 986 children referred to our Spina Bifida Centre in the past 24 years. There were 353 children with open spinal (OSD) and 633 with closed (skin-covered) spinal (CSD) dysraphism. By far the most common open abnormality was myelomeningocele, and all patients with OSD had a Chiari II malformation. CSD was categorised clinically, depending on the presence of a subcutaneous mass in the back. CSD with a mass mainly consisted of lipomas with dural defects and meningoceles, and accounted for 18.8 % of CSD. CSD without a mass were simple (tight filum terminale, intradural lipoma) or complex (split cord malformations, caudal regression). Our suggested classification is easy to use and to remember and takes into account clinical and MRI features; we have found it useful and reliable when making a preoperative neuroradiological diagnosis in clinical practice.


Asunto(s)
Imagen por Resonancia Magnética , Disrafia Espinal/diagnóstico , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Embarazo , Estudios Retrospectivos , Médula Espinal/embriología , Médula Espinal/patología , Disrafia Espinal/clasificación , Disrafia Espinal/embriología
13.
Neuroradiology ; 41(5): 369-75, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10379597

RESUMEN

Contrast-enhancing intracranial masses are rarely found in infants with extracranial capillary haemangiomas (CH). We aimed to assess their nature and progression in three patients undergoing CT and/or MRI. The changes in size of both extra- and intracranial lesions were recorded. In a fourth case, a single examination was obtained. All patients harboured one or two enhancing intracranial nodular, meningeal-based lesions. Diffuse leptomeningeal enhancement of the cerebellar surface was also seen in one, which disappeared at follow-up. In all but one of the cases, the intracranial lesions were on the same side as the extracranial CH. These lesions and the extracranial CH demonstrated parallel changes in size (suggesting that both represent CH) during follow-up of 1-2 years: the size of intracranial lesions and the extracranial CH decreased in two cases, whereas it was unchanged in the third. One patient had a persistent trigeminal artery, while another had cerebellar atrophy with high signal in the cortex on T2-weighted images. In some cases, extracranial CH are part of PHACE syndrome; the association with intracranial CH might represent a peculiar phenotype of this rare vascular phakomatosis. As extracranial CH are known to regress spontaneously in the majority of cases, a conservative approach is recommended also for presumed intracranial CH; surgery should be avoided unless follow-up studies demonstrate growth.


Asunto(s)
Neoplasias de Cabeza y Cuello/diagnóstico , Hemangioma Capilar/diagnóstico , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Femenino , Estudios de Seguimiento , Humanos , Lactante
14.
AJNR Am J Neuroradiol ; 20(4): 724-7, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10319989

RESUMEN

We report an unusual case of extraventricular ("cerebral") neurocytoma with ganglion cells located in the right temporal lobe in a 9-year-old girl with complex partial seizures and precocious puberty. CT showed a calcified mass with central cystic zones. MR imaging showed a markedly hyperintense predominately solid tumor on both T1- and T2-weighted images, without appreciable contrast enhancement. Cerebral neurocytomas are histologically benign and radical surgery is curative; they should be included in the differential diagnosis of temporal lobe tumors in children.


Asunto(s)
Neoplasias Encefálicas/complicaciones , Epilepsia Parcial Compleja/etiología , Neurocitoma/complicaciones , Lóbulo Temporal/patología , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patología , Calcinosis/diagnóstico , Diferenciación Celular , Niño , Medios de Contraste , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Ganglios/patología , Humanos , Imagen por Resonancia Magnética , Neurocitoma/diagnóstico , Neurocitoma/patología , Neuroglía/patología , Pubertad Precoz/etiología , Tomografía Computarizada por Rayos X
15.
AJNR Am J Neuroradiol ; 20(3): 445-56, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10219410

RESUMEN

BACKGROUND AND PURPOSE: Segmental spinal dysgenesis (SSD) is a rare congenital abnormality in which a segment of the spine and spinal cord fails to develop properly. Our goal was to investigate the neuroradiologic features of this condition in order to correlate our findings with the degree of residual spinal cord function, and to provide insight into the embryologic origin of this disorder. We also aimed to clarify the relationship between SSD and other entities, such as multiple vertebral segmentation defects, congenital vertebral displacement, and caudal regression syndrome (CRS). METHODS: The records of patients treated at our institutions for congenital spinal anomalies were reviewed, and 10 cases were found to satisfy the inclusion criteria for SSD. Plain radiographs were available for review in all cases. MR imaging was performed in eight patients, one of whom also underwent conventional myelography. Two other patients underwent only conventional myelography. RESULTS: Segmental vertebral anomalies involved the thoracolumbar, lumbar, or lumbosacral spine. The spinal cord at the level of the abnormality was thinned or even indiscernible, and a bulky, low-lying cord segment was present caudad to the focal abnormality in most cases. Closed spinal dysraphisms were associated in five cases, and partial sacrococcygeal agenesis in three. Renal anomalies were detected in four cases, and dextrocardia in one; all patients had a neurogenic bladder. CONCLUSION: SSD is an autonomous entity with characteristic clinical and neuroradiologic features; however, SSD and CRS probably represent two faces of a single spectrum of segmental malformations of the spine and spinal cord. The neuroradiologic picture depends on the severity of the malformation and on its segmental level along the longitudinal embryonic axis. The severity of the morphologic derangement correlates with residual spinal cord function and with severity of the clinical deficit.


Asunto(s)
Diagnóstico por Imagen , Médula Espinal/anomalías , Columna Vertebral/anomalías , Cóccix/anomalías , Dextrocardia/diagnóstico , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Riñón/anomalías , Vértebras Lumbares/anomalías , Imagen por Resonancia Magnética , Masculino , Mielografía , Sacro/anomalías , Médula Espinal/embriología , Médula Espinal/fisiopatología , Enfermedades de la Columna Vertebral/congénito , Enfermedades de la Columna Vertebral/diagnóstico , Disrafia Espinal/diagnóstico , Columna Vertebral/embriología , Columna Vertebral/patología , Síndrome , Vértebras Torácicas/anomalías , Vejiga Urinaria Neurogénica/diagnóstico
16.
Clin Genet ; 52(3): 184-6, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9377810

RESUMEN

We report a 16-year-old boy, born to consanguineous parents, with mental retardation, gait disturbances and dysarthria; brain magnetic resonance showed features consistent with rhombencephalosynapsis. This condition is characterised by a hypoplastic single-lobed cerebellum. The interest of this case is the presence of common ancestors, pointing to an autosomal recessive inheritance of the malformation.


Asunto(s)
Anomalías Múltiples/genética , Aberraciones Cromosómicas/genética , Cara/anomalías , Rombencéfalo/anomalías , Anomalías Múltiples/patología , Adolescente , Cerebelo/anomalías , Cerebelo/diagnóstico por imagen , Aberraciones Cromosómicas/patología , Trastornos de los Cromosomas , Consanguinidad , Disartria/genética , Disartria/patología , Marcha/genética , Marcha/fisiología , Genes Recesivos/genética , Genes Recesivos/fisiología , Humanos , Discapacidad Intelectual/genética , Discapacidad Intelectual/patología , Imagen por Resonancia Magnética , Masculino , Radiografía , Rombencéfalo/patología
18.
Eur J Pediatr Surg ; 6 Suppl 1: 27-9, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9008816

RESUMEN

Schizencephaly is a rare developmental disorder characterized by a full thickness cleft within the cerebral hemispheres. Large portions of the cerebral hemispheres may be missing and are replaced by cerebrospinal fluid (CSF). The walls of the clefts are lined by polymicrogyric grey matter and are covered by the so-called "pialependymal seam". The cleft may be unilateral or bilateral, and if bilateral are fairly symmetrical. Their dimensions can be small or large. The clinical features may vary from a normal to a severe development delay. 13 patients with this anomaly have been evaluated. Using SSCP (single strand conformation polymorphism) analysis, as previously described (2), they were found to have a mutant homeobox gene, Emx2.


Asunto(s)
Encéfalo/anomalías , Defectos del Tubo Neural/cirugía , Anomalías Múltiples/genética , Anomalías Múltiples/cirugía , Adolescente , Encéfalo/patología , Encéfalo/cirugía , Niño , Preescolar , Análisis Mutacional de ADN , Dominancia Cerebral/genética , Dominancia Cerebral/fisiología , Femenino , Genes Homeobox/genética , Proteínas de Homeodominio/genética , Humanos , Imagen por Resonancia Magnética , Masculino , Proteínas del Tejido Nervioso/genética , Defectos del Tubo Neural/genética , Polimorfismo Conformacional Retorcido-Simple , Factores de Transcripción
19.
Pediatr Radiol ; 26(10): 731-3, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8805608

RESUMEN

The subject of this paper is a 2-year-old child with progressive paraparesis. MRI showed a large lumbosacral intradural-extramedullary mass and the histological diagnosis was Langerhans cell histiocytosis. The histopathological and neuroradiological findings are discussed.


Asunto(s)
Histiocitosis de Células de Langerhans/diagnóstico , Enfermedades de la Médula Espinal/diagnóstico , Preescolar , Femenino , Histiocitosis de Células de Langerhans/patología , Humanos , Imagen por Resonancia Magnética , Enfermedades de la Médula Espinal/patología
20.
Childs Nerv Syst ; 12(6): 303-8, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8816293

RESUMEN

Cystic malformations of the posterior cranial fossa are all but arachnoid cysts contained within the general context of the Dandy-Walker complex and may be further classified in two groups on the basis of their embryological origin: anomalies of the anterior membranous area (AMA) and anomalies of the posterior membranous area (PMA). Whether the latter group of malformations can be regarded as separate entities is still quite controversial. The present authors give a detailed account of the various embryological stages in the formation of the posterior cranial fossa and its contents and propose the identification of two anomalies derived from a defect of the PMA: the mega cisterna magna (MCM) and the persisting Blake's pouch, a new entity with different MRI features from MCM. Criteria for their recognition are discussed, stressing the capital importance of a differential diagnosis in view of the radically different therapeutic approach.


Asunto(s)
Fosa Craneal Posterior/anomalías , Quistes/clasificación , Quistes Aracnoideos/patología , Preescolar , Cisterna Magna/anomalías , Cisterna Magna/patología , Fosa Craneal Posterior/embriología , Fosa Craneal Posterior/patología , Síndrome de Dandy-Walker/diagnóstico , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética
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