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Dive into the research topics where Muriel Brun is active.

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Featured researches published by Muriel Brun.


Brain & Development | 2000

Schizencephaly: clinical and imaging features in 30 infantile cases.

Delphine Denis; Jean-François Chateil; Muriel Brun; Olivier Brissaud; Didier Lacombe; Daniel Fontan; Véronique Flurin; Jean-Michel Pedespan

Schizencephaly is an uncommon structural disorder of cerebral cortical development, characterized by congenital clefts spanning the cerebral hemispheres from the pial surface to the lateral ventricles and lined by cortical gray matter. Either an antenatal environmental incident or a genetic origin could be responsible for this lesion which occurs between the third and fourth month of gestation. We report the clinical and cranial imaging features of 30 children, of whom 15 had unilateral and 15 had bilateral lesions. Their ages at the time of the first presentation ranged from 1 month to 10 years. They were thoroughly studied from clinical, epileptical, imaging and electroencephalographic (EEG) viewpoints. Five patients were investigated by cranial computed tomography (CT), eight by cranial magnetic resonance (MR) imaging, and 17 by both methods. The clinical features consisted of mild hemiparesis in 17 cases (57%), 12/17 were related to a unilateral phenotype (80% of all unilateral forms) and 5/17 to a bilateral phenotype. A tetraparesis was present in nine cases, all of which were due to a bilateral cleft. Bilateral forms were significantly associated with tetraparesis, whereas unilateral forms were associated with hemiparesis. Mental retardation was observed in 17 cases (57%), and was observed significantly more often in bilateral clefts (80%). When both hemispheres are involved, an absence of reorganization of the brain function between the two hemispheres leads to severe mental deficits, in addition to the cerebral anomaly itself. Eleven patients had seizures (seven from unilateral and three from bilateral forms). The degree of malformation was not related to the severity of epilepsy. Migration disorders, such as dysplasia or heterotopia, were observed in 30% of cases and are also important etiopathogenetic factors. The septum pellucidum was absent in 13 cases (43%), with septo-optical dysplasia in two cases. Corpus callosum dysgenesis was noted in 30% of cases. Four cases of mega cisterna magna were noted. Although familial cases and environmental factors have been previously reported, schizencephaly appears to be, in the majority of cases, sporadic.


Pediatric Radiology | 1996

Gastroschisis: are prenatal ultrasonographic findings useful for assessing the prognosis?

Muriel Brun; Andrée Grignon; Laurent Guibaud; Laurent Garel; Dickens Saint-Vil

Objective. The objective of this study was to assess various prenatal patterns in correlation with survival and the occurrence of complications of antenatally recognized gastroschisis (G).Materials and methods. We retrospectively studied 34 cases of G. Mortality and morbidity in the postnatal period were assessed and correlated with the prenatal presence or absence of: (1) bowel and/or stomach dilatation, (2) thickening and/or hyperechogenicity of the intestinal wall, (3) meconium peritonitis (in the abdomen) before 20 weeks of gestation, (4) asymmetrical bowel dilatation, and (5) associated malformations. Morbidity took into account the length of hospitalization and the number of surgical procedures.Results. The overall survival rate was 94 %. Neither bowel nor stomach dilatation was significantly correlated with mortality. However, evidence of intestinal dilatation greater than 17 mm had a positive predictive value of 67 % for atresia, with a negative predictive value of 86 %. Thickening and/or hyperechogenicity of the bowel wall were not significantly associated with mortality. Meconium peritonitis before 20 weeks and asymmetrical bowel dilatation were not statistically significant because of the small sample size. Twelve patients (35.3 %) had postnatal complications, with a mean hospital stay of 127 days. Outcome was not modified by the mode of delivery. Associated extradigestive anomalies were present in 20.6 % of cases. Chromosomal anomalies were not seen.Conclusion. The prognosis of prenatally detected G is excellent despite the frequency of small bowel atresia (67 %) in the group with postnatal complications. Meconium peritonitis before 20 weeks of gestation and/ or asymmetrical bowel dilatation also appear to be indicators of atresia (2/4, 50 %) or high morbidity (3/4,75%).


Pediatric Radiology | 1998

Breast metastases in adolescent girls: US findings.

Jean-François Chateil; Florence Arboucalot; Yves Pérel; Muriel Brun; Martine Boisserie-Lacroix; F. Diard

Abstract We report five adolescent girls with secondary breast tumours. All were imaged by US and the imaging findings have been analysed. Four girls had rhabdomyosarcoma as the primary malignant disease and one had leukaemia. US features were variable, but most of the cases showed heterogeneous nodules which were quite different from the usual benign lesions (fibroadenoma, abscess, cyst) encountered at this age. The metastases produced a variety of echo characteristics: masses with well-defined margins, hyperechoic foci and sonolucent or hypoechoic nodules with posterior attenuation or lacking posterior enhancement. One lesion was round and heterogeneous with a hyperechoic centre. These US findings in an adolescent girl suggest the need for fine-needle aspiration. Mammograms, when performed, never revealed microcalcifications and were quite difficult to analyse at this age, due to the dense glandular breast tissue.


Fetal Diagnosis and Therapy | 2001

Prenatal Diagnosis of Schizencephaly by Fetal Magnetic Resonance Imaging

Delphine Denis; B. Maugey-Laulom; Dominique Carles; Jean-Michel Pedespan; Muriel Brun; Jean-François Chateil

Schizencephaly is a neuronal migration anomaly characterized by gray matter lined clefts extending from the ventricle to the cortical surface leading to specific lesions, well demonstrated by imaging. The lips of the clefts can be fused or separated. Prognosis is related to the extend of the involved cortex. Both genetic and acquired factors can be responsible for this pathology. Three cases of antenatal diagnosed open schizencephaly are reported. Two cases are unilateral and one is bilateral. A cerebral anomaly has been detected in all cases by routine ultrasonography (US) revealing a ventricular dilatation with cortical associated abnormalities. Prenatal magnetic resonance imaging (MRI) permitted the diagnosis in the 3 cases. All cases had led to abortion because of the importance of the cortical defect. The aim of this report is to point out the importance of fetal MRI in the diagnosis of migration disorder and to discuss the medical implications. Indeed, MRI is better suited than US for the prenatal diagnosis of schizencephaly, being able to detect normal and abnormal brain cellular migration, especially with fast imaging (HASTE sequences). With its multiplanar imaging capability, MRI demonstrates the cleft extending from the pial surface to the ventricular ependyma and thus provides characteristic diagnosis of this disorder. Moreover, ventricular dilatation, a frequent anomaly detected by US should be completed with MRI in order to research a neuronal migration disorder.


Pediatric Radiology | 2000

Capillary haemangioma of the greater omentum in a 5-month-old female infant: a case report.

Jean-François Chateil; Caroline Saragne-Feuga; Yves Perel; Muriel Brun; S. Neuenschwander; Pierre Vergnes; F. Diard

Abstract Capillary haemangiomas are frequent benign tumours in infancy. The authors report a case of capillary haemangioma of the greater omentum, discovered in a child of 5 months of age and studied with US, CT and MRI. The localization of such a lesion in the greater omentum is exceptional. Abdominal US revealed a heterogeneous, multinodular intraperitoneal mass. Doppler study demonstrated hypervascularity of the lesion. CT localized the mass to the greater omentum. The mass was hypodense on the unenhanced scan and enhanced massively after injection. The infant suffered a reaction to contrast medium during the CT. MRI demonstrated a mass which was hypointense on T1-weighted images and hyperintense on T2-weighted images. Laparotomy confirmed the location of the mass within the greater omentum and allowed resection of the tumour.


Pediatric Radiology | 1999

Localised proton magnetic resonance spectroscopy of the brain after perinatal hypoxia : a preliminary report

Jean-François Chateil; Bruno Quesson; Muriel Brun; Eric Thiaudière; Jean Sarlangue; Christophe Delalande; Claude Billeaud; Paul Canioni; F. Diard

Objectives. Perinatal hypoxic ischaemic injury is a significant cause of neurodevelopmental impairment. The aim of this study was to evaluate localised proton magnetic resonance spectroscopy (1H-MRS) after birth asphyxia. Materials and methods. Thirty newborn infants suspected of having perinatal asphyxia (Apgar score < 3) were studied. The mean gestational age was 37 weeks, mean age at the MR examination was 18 days and mean weight was 2.9 kg. A 1.5-T unit was used for imaging and spectroscopy. None of the babies had mechanically assisted ventilation. No sedation was used. Axial T1-weighted and T2-weighted images were obtained. 1H-MRS was recorded in a single voxel, localised in white matter, using a STEAM sequence. Results. Image quality was good in 25 of 30 babies. 1H-MRS was performed in 19 of 30 subjects, with adequate quality in 16. Choline, creatine/phosphocreatine and N-acetylaspartate peaks and peak-area ratios were analysed. Lactate was detected in four infants. The N-acetylaspartate/choline ratio was lower in infants with an impaired neurological outcome, but the difference was not statistically significant. Conclusions. This study suggests that 1H-MRS may be useful for assessing cerebral metabolism in the neonate. A raised lactate level and decreased N-acetylaspartate/choline ratio may be predictive of a poor outcome. However, in our experience this method is limited by the difficulty in performing the examination during the first hours after birth in critically ill babies, the problems related to use of a monovoxel sequence, the dispersion of the ratios and the lack of determination of the absolute concentration of the metabolites.


Archives De Pediatrie | 2008

Apport pronostique de la résonance magnétique cérébrale dans l’encéphalopathie hypoxique-ischémique du nouveau-né à terme : score d’imagerie, spectroscopie. Étude de 26 cas

S. Meyer-Witte; Olivier Brissaud; Muriel Brun; D. Lamireau; M. Bordessoules; J.-F. Chateil

UNLABELLED Neonatal hypoxic-ischemic encephalopathy remains a major cause of chronic disability in childhood. Early diagnosis and prognosis are necessary for the clinician to adapt the treatment. However, there is yet no reliable test to predict the patients evolution. OBJECTIVE The aim of our study was to evaluate the predictive value of a personal magnetic resonance imaging (MRI) scoring system and of magnetic resonance spectroscopy (MRS). MATERIAL AND METHODS We included 26 term newborns in condition of neonatal brain suffering. MR examination was performed during the first week of life for all patients and MRI and MRS data were collected. Standardised follow-up visits were made for all patients. Finally, prognostic value of the different criteria was evaluated with statistical tests. RESULTS Our MRI scoring system proved to be linked to prognosis. A high MRI score, abnormal signal in the internal capsule, white matter or basal ganglia abnormalities with diffusion imaging were associated with unfavourable outcome. These results confirmed the data of the literature concerning the MRI predictive value. Our study also confirmed prognostic interest of MR: particularly, ratios using lactate were significantly linked to prognosis in our study. Specificity of the elevation of these ratios was interesting but sensibility was less optimal. CONCLUSION We suggest using our MRI scoring system which associates standard MRI and diffusion imaging, which is significantly related to outcome. We confirm the prognostic value of MRS in this pathological situation. MR with diffusion sequence and spectroscopy, performed three to four days after birth appears to be an essential tool to manage these patients.


Pediatric Radiology | 2005

Chemical shift imaging and localised magnetic resonance spectroscopy in full-term asphyxiated neonates

Olivier Brissaud; Jean-François Chateil; Martine Bordessoules; Muriel Brun


Journal of Pediatric Surgery | 2005

Glomus tumor of the mesocolon

L. Harper; F. Lavrand; Brigitte Le Bail; Muriel Brun; Stephane Ferron; Pierre Oses; Pierre Vergnes


Emc - Radiologie | 2005

Pathologie de l'œsophage chez l'enfant

Loïc Leflot; P. Pietrera; Muriel Brun; J.-F. Chateil

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Olivier Brissaud

Boston Children's Hospital

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Pierre Vergnes

Boston Children's Hospital

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B. Maugey-Laulom

Boston Children's Hospital

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Yves Perel

Boston Children's Hospital

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