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1.
J Neurooncol ; 130(1): 141-148, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27438082

RESUMEN

Cerebral radiation necrosis (CRN) is a toxicity of radiation therapy that can result in significant, potentially life-threatening neurologic deficits. Treatment for CRN has included surgical resection, corticosteroids, hyperbaric oxygen therapy (HBOT), and bevacizumab, but no consensus approach has been identified. We reviewed the available literature to evaluate efficacy of treatment approaches. Using methods specified in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines when possible, we conducted searches of Ovid MEDLINE, Embase and Pubmed to identify studies reporting on outcomes for children (≤21 years old) with CRN. Eligible studies from 1990 to 2014 describing central nervous system (CNS) radiation necrosis with details of both treatment and outcomes were included. Eleven studies meeting criteria were identified. Of the nine studies with total patient denominators, 37 of 806 patients developed CRN (incidence = 4.6 %). Patients received treatment courses of steroids alone (n = 13), steroids with bevacizumab (n = 11) or HBOT (n = 12). Patients who failed to respond to steroids were more likely to be older than steroid-responsive patients (p = 0.009). With the exception of steroid-related adverse events, there was only one report of an adverse event (brainstem stroke) potentially attributable to intervention (bevacizumab). Those who received proton beam RT were both younger (p = 0.001) and had a shorter time to development of CRN (p = 0.079). The most common treatment following steroid initiation was addition of bevacizumab or HBOT, with good success and minimal toxicity. However, randomized controlled trials are needed to establish a definitive treatment algorithm that can be applied to children affected by CRN.


Asunto(s)
Corteza Cerebral/patología , Necrosis/etiología , Necrosis/terapia , Pediatría , Radioterapia/efectos adversos , Bevacizumab/uso terapéutico , Neoplasias Encefálicas/radioterapia , Bases de Datos Bibliográficas/estadística & datos numéricos , Humanos , Esteroides/uso terapéutico
2.
AJNR Am J Neuroradiol ; 43(3): 455-461, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35210278

RESUMEN

BACKGROUND AND PURPOSE: Selumetinib is a promising MAP (mitogen-activated protein) kinase (MEK) 1/2 inhibitor treatment for pediatric low-grade gliomas. We hypothesized that MR imaging-derived ADC histogram metrics would be associated with survival and response to treatment with selumetinib. MATERIALS AND METHODS: Children with recurrent, refractory, or progressive pediatric low-grade gliomas who had World Health Organization grade I pilocytic astrocytoma with KIAA1549-BRAF fusion or the BRAF V600E mutation (stratum 1), neurofibromatosis type 1-associated pediatric low-grade gliomas (stratum 3), or sporadic non-neurofibromatosis type 1 optic pathway and hypothalamic glioma (OPHG) (stratum 4) were treated with selumetinib for up to 2 years. Quantitative ADC histogram metrics were analyzed for total and enhancing tumor volumes at baseline and during treatment. RESULTS: Each stratum comprised 25 patients. Stratum 1 responders showed lower values of SD of baseline ADC_total as well as a larger decrease with time on treatment in ADC_total mean, mode, and median compared with nonresponders. Stratum 3 responders showed a greater longitudinal decrease in ADC_total. In stratum 4, higher baseline ADC_total skewness and kurtosis were associated with shorter progression-free survival. When all 3 strata were combined, responders showed a greater decrease with time in ADC_total mode and median. Compared with sporadic OPHG, neurofibromatosis type 1-associated OPHG had lower values of ADC_total mean, mode, and median as well as ADC_enhancement mean and median and higher values of ADC_total skewness and kurtosis at baseline. The longitudinal decrease in ADC_total median during treatment was significantly greater in sporadic OPHG compared with neurofibromatosis type 1-associated OPHG. CONCLUSIONS: ADC histogram metrics are associated with progression-free survival and response to treatment with selumetinib in pediatric low-grade gliomas.


Asunto(s)
Neoplasias Encefálicas , Glioma , Neurofibromatosis 1 , Bencimidazoles , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Niño , Imagen de Difusión por Resonancia Magnética , Glioma/diagnóstico por imagen , Glioma/tratamiento farmacológico , Glioma/genética , Humanos , Neurofibromatosis 1/diagnóstico por imagen , Neurofibromatosis 1/tratamiento farmacológico , Proteínas Proto-Oncogénicas B-raf
3.
AJNR Am J Neuroradiol ; 41(4): 718-724, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32241771

RESUMEN

BACKGROUND AND PURPOSE: Diffuse intrinsic pontine glioma is a lethal childhood brain cancer with dismal prognosis and MR imaging is the primary methodology used for diagnosis and monitoring. Our aim was to determine whether advanced diffusion, perfusion, and permeability MR imaging metrics predict survival and pseudoprogression in children with newly diagnosed diffuse intrinsic pontine glioma. MATERIALS AND METHODS: A clinical trial using the poly (adenosine diphosphate ribose) polymerase (PARP) inhibitor veliparib concurrently with radiation therapy, followed by maintenance therapy with veliparib + temozolomide, in children with diffuse intrinsic pontine glioma was conducted by the Pediatric Brain Tumor Consortium. Standard MR imaging, DWI, dynamic contrast-enhanced perfusion, and DSC perfusion were performed at baseline and approximately every 2 months throughout treatment. ADC histogram metrics of T2-weighted FLAIR and enhancing tumor volume, dynamic contrast-enhanced permeability metrics for enhancing tumors, and tumor relative CBV from DSC perfusion MR imaging were calculated. Baseline values, post-radiation therapy changes, and longitudinal trends for all metrics were evaluated for associations with survival and pseudoprogression. RESULTS: Fifty children were evaluable for survival analyses. Higher baseline relative CBV was associated with shorter progression-free survival (P = .02, Q = 0.089) and overall survival (P = .006, Q = 0.055). Associations of higher baseline mean transfer constant from the blood plasma into the extravascular extracellular space with shorter progression-free survival (P = .03, Q = 0.105) and overall survival (P = .03, Q = 0.102) trended toward significance. An increase in relative CBV with time was associated with shorter progression-free survival (P < .001, Q < 0.001) and overall survival (P = .004, Q = 0.043). Associations of longitudinal mean extravascular extracellular volume fraction with progression-free survival (P = .03, Q = 0.104) and overall survival (P = .03, Q = 0.105) and maximum transfer constant from the blood plasma into the extravascular extracellular space with progression-free survival (P = .03, Q = 0.102) trended toward significance. Greater increases with time were associated with worse outcomes. True radiologic progression showed greater post-radiation therapy decreases in mode_ADC_FLAIR compared with pseudoprogression (means, -268.15 versus -26.11, P = .01.) CONCLUSIONS: ADC histogram, perfusion, and permeability MR imaging metrics in diffuse intrinsic pontine glioma are useful in predicting survival and pseudoprogression.


Asunto(s)
Neoplasias del Tronco Encefálico/diagnóstico por imagen , Glioma Pontino Intrínseco Difuso/diagnóstico por imagen , Neuroimagen/métodos , Neuroimagen/normas , Adolescente , Algoritmos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Benchmarking , Bencimidazoles/administración & dosificación , Neoplasias del Tronco Encefálico/mortalidad , Neoplasias del Tronco Encefálico/terapia , Quimioradioterapia/métodos , Niño , Glioma Pontino Intrínseco Difuso/mortalidad , Glioma Pontino Intrínseco Difuso/terapia , Progresión de la Enfermedad , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Interpretación de Imagen Asistida por Computador/normas , Imagen por Resonancia Magnética/métodos , Masculino , Imagen de Perfusión/métodos , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Temozolomida/administración & dosificación
4.
AJNR Am J Neuroradiol ; 28(2): 392-3, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17297021

RESUMEN

The cases presented are rare examples of congenital nystagmus associated with isolated absence of the optic chiasm. MR imaging in both patients demonstrated unremarkable anterior optic pathways and optic tracts. No additional midline central nervous system abnormalities, migrational anomalies, space-occupying lesions, or destructive processes were noted. These cases demonstrate that the achiasmatic syndrome should be included in the differential diagnosis of congenital nystagmus and may be overlooked without careful MR imaging evaluation.


Asunto(s)
Imagen por Resonancia Magnética , Nistagmo Congénito/etiología , Nistagmo Congénito/patología , Quiasma Óptico/anomalías , Preescolar , Humanos , Masculino , Vías Visuales/anomalías
5.
J Perinatol ; 37(12): 1278-1284, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28837138

RESUMEN

OBJECTIVE: The relationship between placental and fetal brain growth is poorly understood and difficult to assess. The objective of this study was to interrogate placental and fetal brain growth in healthy pregnancies and those complicated by fetal growth restriction (FGR). STUDY DESIGN: In a prospective, observational study, pregnant women with normal pregnancies or pregnancies complicated by FGR underwent fetal magnetic resonance imaging (MRI). Placental, global and regional brain volumes were calculated. RESULTS: A total of 114 women (79 controls and 35 FGR) underwent MRI (median gestational age (GA) 30 weeks, range 18 to 39). All measured volumes increased exponentially with advancing GA. Placental, total brain, cerebral and cerebellar volumes were smaller in FGR compared with controls (P<0.05). Increasing placental volume was associated with increasing cerebral and cerebellar volumes (P<0.05). CONCLUSION: Quantitative fetal MRI can accurately detect decreased placental and brain volumes in pregnancies with FGR and may provide insight into the timing and mechanisms of brain injury in FGR.


Asunto(s)
Encéfalo/diagnóstico por imagen , Desarrollo Fetal , Retardo del Crecimiento Fetal/diagnóstico por imagen , Imagenología Tridimensional , Imagen por Resonancia Magnética/métodos , Placenta/diagnóstico por imagen , Adolescente , Adulto , Encéfalo/patología , Estudios de Casos y Controles , Femenino , Edad Gestacional , Humanos , Estudios Longitudinales , Masculino , Tamaño de los Órganos , Placenta/patología , Valor Predictivo de las Pruebas , Embarazo , Estudios Prospectivos , Ultrasonografía Prenatal , Adulto Joven
6.
Cancer Chemother Pharmacol ; 58(3): 343-7, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16408203

RESUMEN

BACKGROUND: [corrected] Lobradimil is a synthetic bradykinin analog that rapidly and transiently increases the permeability of the blood-brain barrier (BBB). The combination of lobradimil and carboplatin was studied in pediatric patients with primary brain tumors in a phase II trial, the primary endpoints of which were to estimate the response rate and time to disease progression. PATIENTS AND METHODS: Patients were stratified by histology into five cohorts: brainstem glioma, high-grade glioma, low-grade glioma, medullobastoma/primitive neuroectodermal tumor (PNET), and ependymoma. Patients received carboplatin adaptively dosed to achieve a target AUC of 3.5 mg min/ml per day (7 mg.min/ml/cycle) intravenously over 15 min on 2 consecutive days and lobradimil 600 ng/kg ideal body weight/day on 2 consecutive days each 28 day cycle. RESULTS: Forty-one patients, age 2-19 years, were enrolled; 38 patients, including 1 patient ultimately determined to have atypical neurocytoma, were evaluable for response. No objective responses were observed in the brainstem glioma (n=12) and high-grade glioma (n = 9) cohorts, although two patients with high-grade glioma had prolonged disease stabilization (>6 months). The study was closed for commercial reasons prior to achieving the accrual goals for the ependymoma (n = 8), medulloblastoma/PNET (n = 6) and low-grade glioma (n = 2) cohorts, although responses were observed in 1 patient with PNET and 2 patients with ependymoma. CONCLUSION: The combination of lobradimil and carboplatin was inactive in childhood high-grade gliomas and brainstem gliomas.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Barrera Hematoencefálica/metabolismo , Neoplasias Encefálicas/tratamiento farmacológico , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bradiquinina/administración & dosificación , Bradiquinina/efectos adversos , Bradiquinina/análogos & derivados , Bradiquinina/uso terapéutico , Neoplasias Encefálicas/metabolismo , Carboplatino/administración & dosificación , Carboplatino/efectos adversos , Carboplatino/uso terapéutico , Niño , Preescolar , Estudios de Cohortes , Esquema de Medicación , Humanos , Infusiones Intravenosas , Resultado del Tratamiento
7.
AJNR Am J Neuroradiol ; 37(9): 1733-7, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27102309

RESUMEN

BACKGROUND AND PURPOSE: Age-dependent structural changes of the globes occur during gestation. The posterolateral globe margins bulge outward, and the eyes are conical in early gestation. Later, the globes are ellipsoid. The purpose of this study was to establish normal developmental fetal globe morphology. MATERIALS AND METHODS: The fetal MR imaging data base at an academic children's hospital was queried for all brain MRIs performed during 8 years. Motion artifacts, brain/craniofacial/globe malformations, and chromosomal defects were exclusion criteria. Two board-certified neuroradiologists evaluated each examination for globe shape (elliptic/nonelliptic) and hyaloid visibility. Logistic regression was used to evaluate correlations among variables. Age-specific cut-points for globe shape and hyaloid visibility were chosen to optimize specificity. RESULTS: We identified 1243 examinations from 1177 patients. Six hundred eighty-two examinations met the inclusion criteria (17-39 weeks). Receiver operating characteristic analysis showed that age was highly predictive of globe shape (area under the curve = 0.99) and fetal vasculature visibility (area under the curve = 0.94). Nonelliptic globes were universal up to 22 weeks. Thereafter, globes gradually assumed an elliptic shape, present in nearly all patients 29 weeks and older (sensitivity, 81%; 95% CI, 76%-85%; specificity, 99%; 95% CI, 98%-100%). The hyaloid vasculature was visible in most patients up to 19 weeks and occasionally in those at 20-24 weeks, but never in those 25 weeks and older (sensitivity, 69%; 95% CI, 65%-72%; specificity, 100%; 95% CI, 95%-100%). CONCLUSIONS: Physiologic nonspheric globe shapes are normal up to 29 weeks' gestation and should not be misinterpreted as pathologic. Thereafter, globes are generally elliptic. The timing of this process coincides with the resolution of the primary vitreous and may be related.


Asunto(s)
Encéfalo/diagnóstico por imagen , Feto/diagnóstico por imagen , Imagen por Resonancia Magnética/estadística & datos numéricos , Adulto , Encéfalo/embriología , Circulación Cerebrovascular , Epilepsia/diagnóstico por imagen , Femenino , Desarrollo Fetal , Edad Gestacional , Humanos , Embarazo , Diagnóstico Prenatal , Valores de Referencia , Estudios Retrospectivos
8.
AJNR Am J Neuroradiol ; 37(7): 1338-46, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26988809

RESUMEN

BACKGROUND AND PURPOSE: Brain injury in neonates with congenital heart disease is an important predictor of adverse neurodevelopmental outcome. Impaired brain development in congenital heart disease may have a prenatal origin, but the sensitivity and specificity of fetal brain MR imaging for predicting neonatal brain lesions are currently unknown. We sought to determine the value of conventional fetal MR imaging for predicting abnormal findings on neonatal preoperative MR imaging in neonates with complex congenital heart disease. MATERIALS AND METHODS: MR imaging studies were performed in 103 fetuses with confirmed congenital heart disease (mean gestational age, 31.57 ± 3.86 weeks) and were repeated postnatally before cardiac surgery (mean age, 6.8 ± 12.2 days). Each MR imaging study was read by a pediatric neuroradiologist. RESULTS: Brain abnormalities were detected in 17/103 (16%) fetuses by fetal MR imaging and in 33/103 (32%) neonates by neonatal MR imaging. Only 9/33 studies with abnormal neonatal findings were preceded by abnormal findings on fetal MR imaging. The sensitivity and specificity of conventional fetal brain MR imaging for predicting neonatal brain abnormalities were 27% and 89%, respectively. CONCLUSIONS: Brain abnormalities detected by in utero MR imaging in fetuses with congenital heart disease are associated with higher risk of postnatal preoperative brain injury. However, a substantial proportion of anomalies on postnatal MR imaging were not present on fetal MR imaging; this result is likely due to the limitations of conventional fetal MR imaging and the emergence of new lesions that occurred after the fetal studies. Postnatal brain MR imaging studies are needed to confirm the presence of injury before open heart surgery.


Asunto(s)
Encéfalo/anomalías , Encéfalo/diagnóstico por imagen , Cardiopatías Congénitas/complicaciones , Imagen por Resonancia Magnética/métodos , Diagnóstico Prenatal/métodos , Lesiones Encefálicas/diagnóstico por imagen , Lesiones Encefálicas/etiología , Femenino , Feto , Humanos , Recién Nacido , Embarazo , Sensibilidad y Especificidad
9.
AJNR Am J Neuroradiol ; 37(2): 360-6, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26405083

RESUMEN

BACKGROUND AND PURPOSE: (1)H-MRS provides a noninvasive way to study fetal brain maturation at the biochemical level. The purpose of this study was to characterize in vivo metabolic maturation in the healthy fetal brain during the second and third trimester using (1)H-MRS. MATERIALS AND METHODS: Healthy pregnant volunteers between 18 and 40 weeks gestational age underwent single voxel (1)H-MRS. MR spectra were retrospectively corrected for motion-induced artifacts and quantified using LCModel. Linear regression was used to examine the relationship between absolute metabolite concentrations and ratios of total NAA, Cr, and Cho to total Cho and total Cr and gestational age. RESULTS: Two hundred four spectra were acquired from 129 pregnant women at mean gestational age of 30.63 ± 6 weeks. Total Cho remained relatively stable across the gestational age (r(2) = 0.04, P = .01). Both total Cr (r(2) = 0.60, P < .0001) as well as total NAA and total NAA to total Cho (r(2) = 0.58, P < .0001) increased significantly between 18 and 40 weeks, whereas total NAA to total Cr exhibited a slower increase (r(2) = 0.12, P < .0001). Total Cr to total Cho also increased (r(2) = 0.53, P < .0001), whereas total Cho to total Cr decreased (r(2) = 0.52, P < .0001) with gestational age. The cohort was also stratified into those that underwent MRS in the second and third trimesters and analyzed separately. CONCLUSIONS: We characterized metabolic changes in the normal fetal brain during the second and third trimesters of pregnancy and derived normative metabolic indices. These reference values can be used to study metabolic maturation of the fetal brain in vivo.


Asunto(s)
Encéfalo/embriología , Encéfalo/metabolismo , Desarrollo Fetal , Feto/metabolismo , Espectroscopía de Protones por Resonancia Magnética/métodos , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análisis , Colina/análisis , Colina/metabolismo , Creatina/análisis , Creatina/metabolismo , Femenino , Edad Gestacional , Humanos , Embarazo , Valores de Referencia
10.
Neuro Oncol ; 1(3): 232-50, 1999 07.
Artículo en Inglés | MEDLINE | ID: mdl-11550316

RESUMEN

Medulloblastoma is the most common childhood primary CNS tumor, and treatment approaches have evolved over the past three decades. The biologic underpinnings of medulloblastoma are not fully characterized, but recent work has identified new, important directions for research. Stratification of patients with medulloblastoma into risk groups is the backbone of most ongoing therapeutic studies. Patients are usually characterized as being either average risk or poor risk, although an intermediate risk group may exist. Standard treatment for older children with medulloblastoma consists of radiation and, for most, chemotherapy. Children with nondisseminated disease at the time of diagnosis have been reported to have as high as an 80% five-year disease-free survival rate after treatment with reduced dose (2340 cGy) craniospinal irradiation, local boost radiation therapy (5500 cGy), and chemotherapy, given during and after radiation therapy. Preradiation chemotherapy has yet to be shown to be of benefit for children with medulloblastoma. Children with disseminated disease are a highly problematic subgroup of patients to treat. A variety of new approaches are being studied, most of which are intensifying chemotherapy either prior to or after radiation. Long-term survivors of medulloblastoma are at significant risk for permanent endocrinologic, cognitive, and psychological sequelae. Infants and very young children with medulloblastoma remain a difficult therapeutic challenge because they have the most virulent form of the disease and are at highest risk for treatment-related sequelae.


Asunto(s)
Neoplasias Cerebelosas/patología , Meduloblastoma/patología , Adulto , Factores de Edad , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/análisis , Daño Encefálico Crónico/etiología , Diferenciación Celular , Neoplasias Cerebelosas/diagnóstico , Neoplasias Cerebelosas/tratamiento farmacológico , Neoplasias Cerebelosas/epidemiología , Neoplasias Cerebelosas/radioterapia , Neoplasias Cerebelosas/cirugía , Quimioterapia Adyuvante , Niño , Preescolar , Trastornos del Conocimiento/etiología , Terapia Combinada , Fosa Craneal Posterior , Irradiación Craneana/efectos adversos , Diagnóstico por Imagen , Enfermedades en Gemelos , Predicción , Trastornos del Crecimiento/etiología , Humanos , Lactante , Recién Nacido , Meduloblastoma/diagnóstico , Meduloblastoma/tratamiento farmacológico , Meduloblastoma/epidemiología , Meduloblastoma/radioterapia , Meduloblastoma/cirugía , Persona de Mediana Edad , Proteínas de Neoplasias/análisis , Recurrencia Local de Neoplasia , Tumores Neuroectodérmicos Primitivos/clasificación , Tumores Neuroectodérmicos Primitivos/tratamiento farmacológico , Tumores Neuroectodérmicos Primitivos/epidemiología , Tumores Neuroectodérmicos Primitivos/patología , Tumores Neuroectodérmicos Primitivos/radioterapia , Traumatismos por Radiación/etiología , Tolerancia a Radiación , Radioterapia Adyuvante , Ratas , Factores de Riesgo
11.
Neurology ; 58(10): 1461-70, 2002 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-12041525

RESUMEN

Neurofibromatosis type 1 (NF1) is one of the most common neurogenetic diseases affecting adults and children. Neurofibromas are one of the most common of the protean manifestations of NF1. Plexiform neurofibromas, which will frequently cause cosmetic abnormalities, pain, and neurologic deficits, are composed of "neoplastic" Schwann cells accompanied by other participating cellular and noncellular components. There is increasing evidence that loss of NF1 expression in neoplastic Schwann cells is associated with elevated levels of activated RAS, supporting the notion that the NF1 gene product, neurofibromin, acts as a growth regulator by inhibiting ras growth-promoting activity. In addition, there is increasing evidence that other cooperating events, which may be under cytokine modulation, are important for neurofibroma development and growth. Treatment of plexiform neurofibromas has been empiric, with surgery being the primary option for those with progressive lesions causing a major degree of morbidity. The efficacy of alternative treatment approaches, including the use of antihistamines, maturation agents, and antiangiogenic drugs, has been questionable. More recently, biologic-based therapeutic approaches, using drugs that target the molecular genetic underpinnings of plexiform neurofibromas or cytokines believed important in tumor growth, have been initiated. Evaluation of such trials is hindered by the unpredictable natural history of plexiform neurofibromas and difficulties in determining objective response in tumors that are notoriously large and irregular in shape. Innovative neuroimaging techniques and the incorporation of quality-of-life scales may be helpful in evaluation of therapeutic interventions. The ability to design more rational therapies for NF1-associated neurofibromas is heavily predicated on an improved understanding of the molecular and cellular biology of the cells involved in neurofibroma formation and growth.


Asunto(s)
Terapia Biológica/métodos , Neurofibroma Plexiforme/tratamiento farmacológico , Neurofibromatosis 1/tratamiento farmacológico , Terapia Biológica/estadística & datos numéricos , Ensayos Clínicos como Asunto/métodos , Ensayos Clínicos como Asunto/estadística & datos numéricos , Humanos , Neurofibroma Plexiforme/patología , Neurofibroma Plexiforme/cirugía , Neurofibromatosis 1/patología , Neurofibromatosis 1/cirugía
12.
FEMS Microbiol Lett ; 147(1): 11-6, 1997 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-9037757

RESUMEN

A 4.4-kb DNA fragment was cloned from Actinobacillus pleuropneumoniae (strain 4074, serotype 1) by genetic complementation with Escherichia coli groES-groEL mutant strains. Sequence analysis of this fragment revealed a purine nucleoside phosphorylase (DeoD)-encoding gene homolog (deoD), heat-shock response-encoding genes for the small (groES) and large subunits (groEL) and a partial open reading frame encoding an alcohol dehydrogenase homolog (adhE). The predicted amino-acid sequence of groES and groEL genes showed extensive sequence identity (80-95%) with other Pasteurellaceae. The gene organization surrounding the groE locus was different from that of Haemophilus infuenzae. When expressed in E. coli, groES-groEL genes were capable of complementing the growth of a lambda lytic phage, indicating a structural as well as functional conservation.


Asunto(s)
Actinobacillus pleuropneumoniae/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/genética , Actinobacillus pleuropneumoniae/enzimología , Alcohol Deshidrogenasa/genética , Chaperoninas , Clonación Molecular , Proteínas de Escherichia coli , Prueba de Complementación Genética , Datos de Secuencia Molecular , Mutación/genética , Purina-Nucleósido Fosforilasa/genética , Mapeo Restrictivo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
13.
AJNR Am J Neuroradiol ; 21(4): 790-4, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10782799

RESUMEN

BACKGROUND AND PURPOSE: Medulloblastoma is one of the most common posterior fossa tumors to occur in children. Our purpose was to document the frequency, location, and time of occurrence of intracranial calcifications in cranial CT studies of children with medulloblastoma. METHODS: We retrospectively reviewed cranial CT studies of 56 patients diagnosed with medulloblastoma from 1983 through 1997 for the presence of intracranial calcifications. The findings were compared with 159 cranial CT studies of patients who were evaluated in the emergency department (control group). Thirty-two patients with medulloblastoma without shunts were compared with 118 patients from the control group without shunts. Similarly, 24 patients with medulloblastoma with shunts were compared with 41 patients from the control group with shunts. RESULTS: Overall, three (9%) patients with medulloblastoma without shunts, four (16%) patients with medulloblastoma with shunts, and four (10%) patients from the control group with shunts had falx calcification. Only the two children carrying the diagnoses of medulloblastoma and nevoid basal cell carcinoma syndrome, however, had calcification of the falx cerebri shown on the cranial CT scans obtained during the peridiagnostic period. Both were diagnosed with medulloblastoma before the age of 3 years and later developed jaw cysts and multiple basal cell carcinomas in the radiation field. CONCLUSION: Previous studies have shown that falx calcification is a major component of nevoid basal cell carcinoma syndrome. Our two cases illustrate the importance of considering the diagnosis of nevoid basal cell carcinoma syndrome when falx calcification is present in young patients with medulloblastoma. If the concomitant diagnosis of nevoid basal cell carcinoma syndrome is made, alternative types of therapy should be sought to minimize radiation therapy sequelae.


Asunto(s)
Síndrome del Nevo Basocelular/complicaciones , Encefalopatías/complicaciones , Calcinosis/complicaciones , Neoplasias Cerebelosas/complicaciones , Meduloblastoma/complicaciones , Neoplasias Primarias Múltiples/complicaciones , Adolescente , Adulto , Síndrome del Nevo Basocelular/diagnóstico por imagen , Encefalopatías/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Neoplasias Cerebelosas/diagnóstico por imagen , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Meduloblastoma/diagnóstico por imagen , Neoplasias Primarias Múltiples/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
14.
AJNR Am J Neuroradiol ; 22(1): 190-5, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11158908

RESUMEN

BACKGROUND AND PURPOSE: Many pediatric patients with neurofibromatosis type 1 (NF-1) have an apparent increased thickness of the corpus callosum (CC) on sagittal T1-weighted images compared with patients not affected by NF-1. In this study, we compared the surface area of the CC in children with NF-1 with that of healthy pediatric control subjects to determine if this was another common intracranial manifestation of NF-1. METHODS: Midsagittal T1-weighted MR images of 43 consecutive children with NF-1 and 43 age- and gender-matched healthy control subjects were reviewed retrospectively. The surface area of the CC and the midsagittal intracranial skull surface (MISS) area were measured five times each on all midsagittal images. A mean CC to mean midline intracranial surface area ratio (CC/MISS) was calculated for each. RESULTS: There is a statistically significant increase in the mean CC surface area in pediatric patients with NF-1 (680 mm2 +/- 98, range 509-974 mm2) compared with control subjects (573 mm2 +/- 83, range 404-797 mm2). The mean MISS is significantly increased in patients with NF-1 (16568 mm2 +/- 1161, range 14107-19394 mm2 vs 15402 mm2 +/- 1133, range 12951-17905 mm2 for control subjects). CC/MISS was also significantly increased in the patients with NF-1 relative to the control subjects (.0410 +/- .0043, range .0330-.0530 vs .0372 +/- .0043, range .0270-.0470 for control subjects). CONCLUSION: A larger midsagittal surface area of the CC is another intracranial manifestation of NF-1 that can be demonstrated by sagittal MR imaging. The etiology is unclear, but could be related to abnormal neurofibromin and Ras protein activity. Potential clinical relevance is discussed herein.


Asunto(s)
Cuerpo Calloso/patología , Imagen por Resonancia Magnética , Neurofibromatosis 1/diagnóstico , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Valores de Referencia , Estudios Retrospectivos , Cráneo/patología
15.
AJNR Am J Neuroradiol ; 17(2): 287-94, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8938301

RESUMEN

PURPOSE: To determine the frequency of intracranial lesions in infants treated with extracorporeal membrane oxygenation (ECMO), to evaluate trends in frequency during an 8-year period, and to determine which infants are at highest risk for intracranial injury. METHODS: Daily sonograms were obtained in 386 infants during treatment with ECMO. Cranial CT scans were acquired after decannulation in 286 of 322 survivors. Abnormalities were classified as major or minor and hemorrhagic or nonhemorrhagic. Results were correlated with infant demographic data. RESULTS: Intracranial abnormalities were detected in 203 (52%) of the 386 infants; 73 (19%) hemorrhagic, 86 (22%) nonhemorrhagic, and 44 (11%) combined lesions. Eighty-two lesions (21%) were classified as major. Forty-six (94%) of 49 major hemorrhages were identified at sonography. CT contributed additional information in 73% of neonates with intracranial abnormalities, of which 17 were major lesions not identified at sonography. The frequency of intracranial hemorrhage was increased in infants who were septic or premature or weighed less than 2.5 kg. An increase in time spent on ECMO bypass increased the risk for nonhemorrhagic injury. During an 8-year period, the frequency of hemorrhagic and major nonhemorrhagic lesions remained constant, whereas minor nonhemorrhagic abnormalities increased significantly. CONCLUSION: Infants treated with ECMO continue to be at high risk for cerebrovascular injury. Although daily sonograms are useful in identifying major hemorrhages, follow-up CT scans are crucial for accurate evaluation of intracranial abnormalities.


Asunto(s)
Daño Encefálico Crónico/diagnóstico , Ecoencefalografía , Oxigenación por Membrana Extracorpórea , Hipoxia Encefálica/diagnóstico , Enfermedades del Prematuro/terapia , Tomografía Computarizada por Rayos X , Daño Encefálico Crónico/mortalidad , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Hipoxia Encefálica/mortalidad , Lactante , Recién Nacido , Enfermedades del Prematuro/etiología , Enfermedades del Prematuro/mortalidad , Masculino , Factores de Riesgo , Tasa de Supervivencia
16.
Radiol Clin North Am ; 37(6): 1147-61, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10546671

RESUMEN

Diagnostic imaging plays an important role in evaluating the preterm infant with hypoxic-ischemic injury. The pathologic and radiographic findings of IVH, focal white matter necrosis, and severe anoxic damage are well documented. New observations, including diffuse white matter and cerebellar insults in some survivors, are being made. Understanding the complex relationships between these findings, clinical events (both prenatal and postnatal), and neurocognitive outcome of the preterm infants, however, requires further study.


Asunto(s)
Diagnóstico por Imagen , Hipoxia Encefálica/diagnóstico , Enfermedades del Prematuro/diagnóstico , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatología , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/fisiopatología , Infarto Cerebral/complicaciones , Infarto Cerebral/diagnóstico , Infarto Cerebral/fisiopatología , Humanos , Hipoxia Encefálica/etiología , Hipoxia Encefálica/fisiopatología , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/fisiopatología , Leucomalacia Periventricular/diagnóstico , Leucomalacia Periventricular/etiología , Leucomalacia Periventricular/fisiopatología
17.
J Neurosurg ; 92(2): 249-54, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10659011

RESUMEN

OBJECT: The outcome for children with recurrent malignant brain tumors is poor. The majority of patients die of progressive disease within months of relapse, and other therapeutic options are needed. The goal of this Phase I study was to evaluate the safety of in vivo suicide gene therapy in 12 children with recurrent, malignant, supratentorial brain tumors. METHODS: After optimal repeated tumor resection, multiple injections of murine vector-producing cells shedding murine replication-defective retroviral vectors coding the herpes simplex virus thymidine kinase type 1 (HSV-Tk1) gene were made into the rim of the resection cavity. Fourteen days after the vector-producing cells were injected, ganciclovir was administered for 14 days. The retroviral vector that was used only integrated and expressed HSV-Tk1 in proliferating cells, which are killed after a series of metabolic events lead to cell death. The median age of the patients was 11 years (range 2-15 years). Treated brain tumors included seven malignant gliomas, two ependyminomas, and three primitive neuroectodermal tumors. The patients were treated with one of three escalating dose concentrations of vector-producer cells. Four transient central nervous system adverse effects were considered possibly related to the vector-producing cells. In no child did permanent neurological worsening or ventricular irritation develop, and tests for replication-competent retroviruses yielded negative findings. CONCLUSIONS: This Phase I study demonstrates that in vivo gene therapy in which a replication-defective retroviral vector in murine vector-producing cells is delivered by brain injections can be performed with satisfactory safety in a select group of children with localized supratentorial brain tumors.


Asunto(s)
Antivirales/administración & dosificación , Ganciclovir/administración & dosificación , Terapia Genética/métodos , Vectores Genéticos/genética , Recurrencia Local de Neoplasia/terapia , Simplexvirus/genética , Neoplasias Supratentoriales/terapia , Timidina Quinasa/genética , Adolescente , Animales , Antivirales/efectos adversos , Encéfalo/patología , Muerte Celular/genética , Niño , Terapia Combinada , Supervivencia sin Enfermedad , Ependimoma/genética , Ependimoma/patología , Ependimoma/terapia , Femenino , Ganciclovir/efectos adversos , Glioma/genética , Glioma/patología , Glioma/terapia , Humanos , Infusiones Intravenosas , Inyecciones Intralesiones , Imagen por Resonancia Magnética , Masculino , Ratones , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Tumores Neuroectodérmicos Primitivos/genética , Tumores Neuroectodérmicos Primitivos/patología , Tumores Neuroectodérmicos Primitivos/terapia , Calidad de Vida , Neoplasias Supratentoriales/genética , Neoplasias Supratentoriales/patología
18.
AJNR Am J Neuroradiol ; 35(10): 2002-6, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24874532

RESUMEN

Interhypothalamic adhesion is a newly described disease entity, characterized by an abnormal parenchymal band connecting the medial margins of the hypothalami across the third ventricle. Additional anomalies, including cleft palate, gray matter heterotopia, cerebellar hypoplasia, optic atrophy, hippocampal under-rotation, and white matter lesions, may coexist. The purpose of this clinical report is to describe the imaging findings from a series of 13 patients with interhypothalamic adhesions discovered on brain MR imaging.


Asunto(s)
Encefalopatías/patología , Hipotálamo/anomalías , Encéfalo/anomalías , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino
19.
AJNR Am J Neuroradiol ; 35(8): 1593-9, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24651820

RESUMEN

BACKGROUND AND PURPOSE: Brain injury is a major complication in neonates with complex congenital heart disease. Preliminary evidence suggests that fetuses with congenital heart disease are at greater risk for brain abnormalities. However, the nature and frequency of these brain abnormalities detected by conventional fetal MR imaging has not been examined prospectively. Our primary objective was to determine the prevalence and spectrum of brain abnormalities detected on conventional clinical MR imaging in fetuses with complex congenital heart disease and, second, to compare the congenital heart disease cohort with a control group of fetuses from healthy pregnancies. MATERIALS AND METHODS: We prospectively recruited pregnant women with a confirmed fetal congenital heart disease diagnosis and healthy volunteers with normal fetal echocardiogram findings who underwent a fetal MR imaging between 18 and 39 weeks gestational age. RESULTS: A total of 338 fetuses (194 controls; 144 with congenital heart disease) were studied at a mean gestational age of 30.61 ± 4.67 weeks. Brain abnormalities were present in 23% of the congenital heart disease group compared with 1.5% in the control group (P < .001). The most common abnormalities in the congenital heart disease group were mild unilateral ventriculomegaly in 12/33 (36.4%) and increased extra-axial spaces in 10/33 (30.3%). Subgroup analyses comparing the type and frequency of brain abnormalities based on cardiac physiology did not reveal significant associations, suggesting that the brain abnormalities were not limited to those with the most severe congenital heart disease. CONCLUSIONS: This is the first large prospective study reporting conventional MR imaging findings in fetuses with congenital heart disease. Our results suggest that brain abnormalities are prevalent but relatively mild antenatally in fetuses with congenital heart disease. The long-term predictive value of these findings awaits further study.


Asunto(s)
Encéfalo/anomalías , Enfermedades Fetales/patología , Cardiopatías Congénitas/complicaciones , Adulto , Femenino , Enfermedades Fetales/diagnóstico , Feto , Humanos , Recién Nacido , Embarazo , Prevalencia , Estudios Prospectivos
20.
AJNR Am J Neuroradiol ; 34(4): 895-8, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23153867

RESUMEN

Failure to detect FCD and similar lesions encountered in patients with tuberous sclerosis can have significant clinical consequences, such as preventing surgical intervention for medically refractory epilepsy and misguiding prognostic information regarding cognitive development. Here, we show the beneficial effects on detection of FCD and cortical tubers when using a magnetization transfer T1 sequence for children with seizures who underwent MR imaging at our institution.


Asunto(s)
Encefalopatías/patología , Encéfalo/patología , Epilepsia/patología , Imagen por Resonancia Magnética , Malformaciones del Desarrollo Cortical/patología , Esclerosis Tuberosa/patología , Niño , Preescolar , Electroencefalografía , Femenino , Humanos , Lactante , Masculino , Malformaciones del Desarrollo Cortical de Grupo I , Pronóstico
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