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Biomedical subjects

F Brunelle

Publications and source records attributed to F Brunelle.

At least 91 records · Page 5Linked to original sources

Lung growth and maturation after tracheal occlusion in diaphragmatic hernia.

Tracheal occlusion (TO) was performed at 120 d of gestation by noninvasive endoscopic technique using a releasable latex balloon, in fetal lambs with diaphragmatic hernia (DH) established at 85 d. The lungs were studied at 139 d in five fetuses with DH + TO, five fetuses with DH only, and six control fetuses. Fluid retention consecutive to TO allowed fetal lungs to grow. Histological pulmonary structure was more mature in DH + TO than in DH alone. The growth-inducing effect of TO was however incomplete, with an increased protein/DNA ratio. Tissue phospholipids were increased, but this was not reflected in the surfactant compartment. The major surfactant component, disaturated phosphatidylcholine, was reduced to 58% of its control value in DH, and further reduced to 17.5% of its control value in DH + TO. The proportion of surfactant protein B immunoreactive cells, assumed to represent the proportion of type II cells, was increased in DH (27% of all parenchymal cells), and reduced in DH + TO (7.8%) as compared with control fetuses (15%). In conclusion, although noninvasive tracheal occlusion in utero is feasible and may partly compensate the adverse effects of DH on lung organogenesis, it reduces the number of type II cells and induces a dramatic surfactant deficit. Using this technique in human fetuses requires careful consideration until further evaluation of lung functional characteristics has been achieved in this experimental model.

Animals↗

Hydrocephalus and craniosynostosis.

OBJECT: A retrospective study of 1727 cases of craniosynostosis was undertaken to determine the interrelationship between abnormal cerebrospinal fluid (CSF) hydrodynamics and craniosynostosis. METHODS: The patients were divided into two groups: nonsyndromic craniosynostosis and syndromic craniosynostosis. Cases of occipital plagiocephaly without suture synostosis and cases of shunt-induced craniosynostosis were excluded from the study. The majority of patients (1297) were treated surgically for their cranial deformity; 95% of these patients had a postoperative follow-up review period lasting 5 years. Clinical and radiographic charts covering the time from presentation through the follow-up period were reviewed. CONCLUSIONS: Abnormal intracranial CSF hydrodynamics was found in 8.1% of the patients (3.4% of whom had received shunts and 4.5% of whom had not). Three types of CSF hydrodynamic disturbance were observed: progressive hydrocephalus with ventricular dilation, nonprogressive ventriculomegaly, and dilation of the subarachnoid spaces. Hydrocephalus occurred much more frequently in patients with syndromic craniosynostosis (12.1%) than in those with isolated craniosynostosis (0.3%). In fact, patients with kleeblattschädel exhibited hydrocephalus as a constant feature and patients with Crouzon's syndrome were far more likely to have hydrocephalus than those with other syndromes. In Apert's syndrome, ventricular dilation occurred very frequently, but it was almost always nonprogressive in nature. In most cases of syndromic craniosynostosis, venous sinus obstruction and/or chronic tonsillar herniation were found. Their role in the pathophysiology of hydrocephalus in craniosynostosis is discussed.

Acrocephalosyndactylia↗

Papillomas and carcinomas of the choroid plexus in children.

OBJECT: Choroid plexus tumors are rare intraventricular tumors (1% of all intracranial tumors) that occur mainly in children. The pathophysiological characteristics of associated hydrocephalus, surgical management, and oncological issues related to these tumors remain a matter of debate. To understand more about these tumors, the authors have reviewed their experience with the management of 38 children with choroid plexus tumors. METHODS: There were 25 cases of papilloma and 13 of carcinoma. The mean age of the patients at presentation was 22.5 months, and one-half of the patients were younger than 2 years of age. Hydrocephalus was present in 33 patients and poorly correlated with the size, site, and pathological characteristics of the tumor. In nine children, a ventriculoperitoneal shunt was required after tumor excision, calling into question the notion that cerebrospinal fluid oversecretion is the only cause of hydrocephalus. Complete excision was achieved in 96% of the cases of papilloma and 61.5% of the cases of carcinoma. These surgical procedures were complicated by the risks of intraoperative hemorrhage, which proved to be fatal in two cases, and postoperative brain collapse, which led to subdural fluid collections requiring subdural shunt placement in six patients. Preoperative embolization was partially successful in four cases and significantly assisted surgery. Preoperative controlled drainage of excessively dilated ventricles and intraoperative gluing of the cortical incision have been used to address the problem of postoperative brain collapse. Patients with carcinomas were treated postoperatively by chemotherapy alone (seven cases), radiotherapy (one case), or chemotherapy plus radiotherapy (one case). The overall 5-year survival rate was 100% for patients with papillomas and 40% for those with carcinomas. CONCLUSIONS: Total surgical excision is curative in cases of papillomas. For carcinomas, the most effective treatment remains total surgical excision; however, adjuvant treatment in the form of chemotherapy in patients younger than age 3 years, supplemented by radiation therapy in older children, can moderately reduce the risk of recurrence.

Adolescent↗

Loss of imprinted genes and paternal SUR1 mutations lead to hyperinsulinism in focal adenomatous hyperplasia.

Two types of histopathological lesions, a focal adenomatous hyperplasia of islet cells of the pancreas in about 30% of operated sporadic cases, and a diffuse form can be observed in congenital hyperinsulinism, or Persistent Hyperinsulinemic Hypoglycemia of Infancy (PHHI). In sporadic focal forms, specific losses of maternal alleles (LOH) of the imprinted chromosomal region 11p15, restricted to the hyperplastic area of the pancreas, were observed. Similar mechanisms are observed in embryonal tumors and in the Beckwith-Wiedemann syndrome which is also associated with neonatal but transient hyperinsulinism. However this region also contains the sulfonylurea receptor (SUR1) gene and the inward rectifying potassium channel subunit (KIR6.2) gene, involved in recessive familial forms of PHHI, but not known to be imprinted. We now report somatic reduction to hemizygosity or homozygosity of a paternal SUR1 constitutional heterozygous mutation, in five patients with a focal form of PHHI. Thus this somatic event (LOH) which leads both to b cell proliferation and to hyperinsulinism can be considered as the somatic equivalent, restricted to a microscopic focal lesion, of constitutional uniparental disomy associated with unmasking of a heterozygous parental mutation leading to a somatic recessive disorder.

ATP-Binding Cassette Transporters↗

[Intrahepatic arteriovenous fistula. Prenatal diagnosis, physiopathological study and neonatal management]l.

A case of arteriovenous fistula of the liver diagnosed at 30 weeks of gestation is reported. The etiologies of an hypoechogenic structure in the fetal liver are discussed showing the contribution of pulsed wave Doppler and color Doppler to the diagnosis. The clinical evolution towards heart failure led us to examine the pathophysiology of such a lesion. The prenatal management of this arteriovenous malformation is exposed.

Adult↗

Somatic deletion of the imprinted 11p15 region in sporadic persistent hyperinsulinemic hypoglycemia of infancy is specific of focal adenomatous hyperplasia and endorses partial pancreatectomy.

Sporadic persistent hyperinsulinemic hypoglycemia of infancy (PHHI) or nesidioblastosis is a heterogeneous disorder characterized by profound hypoglycemia due to inappropriate hypersecretion of insulin. An important diagnostic goal is to distinguish patients with a focal hyperplasia of islet cells of the pancreas (FoPHHI) from those with a diffuse abnormality of islets (DiPHHI) because management strategies differ significantly. 16 infants with sporadic PHHI resistant to diazoxide and who underwent pancreatectomy were investigated. Selective pancreatic venous sampling coupled with peroperative surgical examination and analysis of extemporaneous frozen sections allowed us to identify 10 cases with FoPHHI and 6 cases with DiPHHI. We show here that in cases of FoPHHI, but not those of DiPHHI, there was specific loss of maternal alleles of the imprinted chromosome region 11p15 in cells of the hyperplastic area of the pancreas but not in normal pancreatic cells. This somatic event is consistent with a proliferative monoclonal lesion. It involves disruption of the balance between monoallelic expression of several maternally and paternally expressed genes. Thus, we provide the first molecular explanation of the heterogeneity of sporadic forms of PHHI such that it is possible to perform only partial pancreatectomy, limited to the focal somatic lesion, so as to avoid iatrogenic diabetes in patients with focal adenomatous hyperplasia.

Chromosome Deletion↗

Arteriovenous malformation of the vein of Galen in children.

Arteriovenous malformation of the vein of Galen (VGM) is a unique vascular anomaly in children. Its extra parenchymal location allows for aggressive endovascular treatment. Depending on the age of the child, the clinical presentation of VGM varies from congestive heart failure to hydrocephalus. The deleterious consequences to the brain depend on many factors, the most important of which is the volume of blood shunting through the malformation and away from the brain parenchyma ("steal" phenomenon). High flow in a fetus with a developing brain will lead not only to brain ischemia but also to multiple organ failure. At the other end of the spectrum, a small malformation can be well tolerated. Treatment should be tailored to each individual case.

Cerebral Veins↗

Vein of Galen vascular malformations in infants: clinical, radiological and therapeutic aspect.

A series of 14 vein of Galen vascular malformations diagnosed in the pediatric populations and treated at the Hospital for Sick Children-Necker, Paris, between 1988 and 1994 is presented. Five of the patients were diagnosed in the neonatal period, of whom 4 presented with life-threatening, intractable cardiac decompensation and high-flow arteriovenous fistulae. Embolization was performed on vital indications in 4 patients during the first week after birth. One embolization failed with fatal outcome. Of the 3 who were embolized, 2 succumbed within 1 week and 1 survived with marked improvement of cardiac symptoms. The older children presented with hydrocephalus and neurologic symptoms. The 10 patients older than 1 year were embolized. These procedures were successful in 90 %, with hemodynamic stabilization and improvement of clinical symptoms. In this group the mortality rate was 10 %. The total mortality rate was 29 %. Hydrocephalus was secondary to a compression of the Sylvian aqueduct in 44 % of cases. Five patients had ventricular drainage before embolization followed by a staged elective embolization. Transarterial embolizations were performed in 11 patients, whereas 2 patients were embolized via the transvenous route.

Arteriovenous Fistula↗

Congenital lumbosacral lipomas.

Congenital lumbosacral lipomas can be responsible for progressive defects. The general feeling is that tethering of roots, filum, or cord probably explains this evolution, and that untethering of these structures could prevent late deterioration. Like the vast majority of neurosurgeons, we too have routinely and systematically operated on lumbosacral lipomas, even in the absence of neurological deficits. This policy stemmed from our belief that spontaneous neurological deterioration was frequent, recovery from preoperative deficits rare, and surgery both efficient and benign in nature. After 22 years of experience, we felt that it was necessary to review our series of 291 lipomas (38 lipomas of the filum and 253 of the conus) operated on from 1972 to 1994. To reassess the value of prophylactic surgery, we attempted an accurate evaluation of (1) the risk of pathology, (2) the risks involved in surgery, (3) the postoperative outcome with respect to preoperative deficits, and (4) the postoperative outcome in asymptomatic patients at 1 year and at maximum follow-up. Special attention was paid to 93 patients whose postoperative follow-up was more than 5 years (average 8.7, median 8, range 5-23 years). Of these 93 patients, 39 were asymptomatic preoperatively (7 with lipoma of the filum and 32 with lipoma of the conus). Lipomas of the filum and of the conus are entirely different lesions and were studied separately. In 6 cases prenatal diagnosis had been possible. The mean age at surgery was 6.4 years. Low back skin stigmata were present in 89.4% of cases. Preoperative neurological deficits existed in 57% of the patients and were congenital in 22%. Clinical signs and symptoms recorded were pain in 13.3% of the patients and/or neurological deficits affecting sphincter (52%), motor (27.6%) and sensory (22.4%) functions. Deficits were progressive in 22.4% of cases, slowly progressive in 58.8% of these and rapidly progressive in the remaining 41.2%. In 36 patients (13.2%) the lipomas were seen to grow either subcutaneously or intraspinally. Among these patients, 21 were infants, 2 were obese adolescents, and 10 were pregnant women. The metabolism of the fat within the lipomas was studied in 11 patients and found to be similar to that at other sites. Lipomas were associated with various other malformations, either intra- or extraspinal. These associated anomalies were rare in the case of lipomatous filum (5.2%) but frequent with lipomas of the conus, except for intracranial malformations (3.6%). Therapeutic objectives were spinal cord untethering and decompression, sparing of functional neural tissue and prevention of retethering. Procedures used to achieve these goals were subtotal removal of the lipoma, intraoperative monitoring, duroplasty, and sometimes closure of the placode. Histologically, lipomas consisted of normal mature fat. However, 77% of them also included a wide variety of other tissues, originating from ectoderm, mesoderm, or entoderm. This indicates that lipomas are either simple or complex teratomas. The results of the study are as follows. (1) Surgery was easy and safe when performed for treatment of lipomas of the filum (no complications), but difficult and hazardous in the case of lipomas of the conus (20% local, 3.9% neurological complications). (2) All types of deficit could be improved by surgery, which was beneficial in all cases of lipoma of the filum and 50% of cases of lipoma of the conus. (3) In asymptomatic patients long-term surgical results depended on the anatomical type of the lipoma. They were excellent in lipomas of the filum. In lipomas of the conus they were good in the short term but eroded with time. At more than 5 years of follow-up only 53.1% of the patients were still free of symptoms. (4) Reoperations were performed in 16 patients (5.5%), 5 (31.2%) of whom improved postoperatively, while in 7 (43.7%) progression stopped, in 3 (18.7%) deterioration continued and in 1 (6.2%) the condition was wor

Adolescent↗

Pituitary stalk interruption syndrome: a clinical-biological-genetic assessment of its pathogenesis.

The detection of pituitary stalk interruption syndrome (PSIS) by magnetic resonance imaging is a diagnostic marker of permanent GH deficiency (GHD), but the pathogenesis of PSIS is unknown. Fifty-one patients (27 males) with GHD and PSIS were classified according to whether the GHD was isolated (group 1, 16 cases) or associated with other anterior pituitary abnormalities (group 2, 35 cases). The 2 groups had similar characteristics (frequencies of perinatal abnormalities, ages at occurrence of first signs and at diagnosis, height, GH peak response to stimuli other than GHRH), but associated malformations were less frequent in group 1 (12%) than in group 2 (54%; P < 0.01), hypoglycemia occurred in 25% of group 1 and 70% of group 2 (P < 0.01), and the GH peak response to GHRH was less than 10 micrograms/L in 0% of group 1 (4 cases evaluated) and 57% of group 2 (21 cases; P < 0.05). Thirty-one cases (61%; 25 from group 2) had features suggesting an antenatal origin: familial form (4 cases), microphallus (10 boys), and/or associated malformations (50%; 21 cases). Twenty-seven cases (53%, 22 from group 2) had features suggesting a hypothalamic origin. The three group 1 patients with a GH peak of 1 microgram/L or less had no large GH-N gene deletion. One familial form had no linkage between the GHD phenotype and abnormal GH-N locus, and the only mutation described to date in the GHRH receptor gene was absent. The two patients with low plasma PRL levels had no Pit-1 gene abnormality. Thus, most of the patients with GHD associated with multiple anterior pituitary abnormalities and PSIS have features suggesting an antenatal origin. The GH-N, GHRH receptor, and Pit-1 genes do not seem to be implicated in PSIS.

Adolescent↗

Giant perimedullary arteriovenous fistulas of the spine: clinical and radiologic features and endovascular treatment.

PURPOSE: To present the clinical and radiologic features of giant perimedullary arteriovenous fistulas (GAVFs) in 12 consecutive cases and to evaluate the results of endovascular treatment. METHODS: We retrospectively reviewed the clinical and radiologic data as well as the results of balloon endovascular treatment obtained from 1980 to 1989. RESULTS: GAVFs, defined as large intradural perimedullary direct arteriovenous high-flow shunts, are revealed mainly in childhood either by subarachnoid hemorrhage or by progressive neurologic disorders. MR imaging and myelography show major vascular dilatations. The angioarchitecture of GAVFs can only be assessed by selective spinal angiography. Ten patients were treated by balloon occlusion resulting in eight anatomic cures and six good clinical results. One balloon migrated to the venous side, leading to clinical deterioration. CONCLUSION: GAVF is a special subgroup of intradural perimedullary arteriovenous fistula. The endovascular approach should be the first line of treatment, with surgery reserved for special circumstances. Nondetachable balloon occlusion is a safe and efficient method for treating GAVFs.

Adult↗

[Spindle-cell hemangioendothelioma with monomelic and multifocal form in a child].

BACKGROUND: Spindle-cell hemangioendothelioma is a soft tissue skin tumor recently identified histologically. It can occur at all ages but generally is seen in young adults. The lesion usually occurs as a subcutaneous mass involving the limbs. CASE REPORT: A particular case of spindle-cell hemangioendothelioma was observed in an 18-month-old child. The lesions progressed with a monomelic distribution on the upper limb. Histological diagnosis of spindle-cell hemangioendothelioma was achieved at the age of 6 years. DISCUSSION: The age of the patient and the monomelic distribution is particular in this case of spindle-cell hemangioendothelioma, inciting a nosological discussion on this disease and other vascular tumors of childhood and the relationship of these types of lesions with Maffucci's syndrome. Although no anomalies have been detected to date, radiological surveillance is needed as cases of Maffucci's syndrome associated with spindle-cell hemangioendothelioma is described in the literature.

Hand↗

Prenatal MRI diagnosis of fetal cerebral tuberous sclerosis.

Tuberous sclerosis (TS) is an autosomal dominant phakomatosis. A high percentage of spontaneous mutations leads to the diagnosis of new cases in normal families. This diagnosis is suspected at antenatal ultrasound on the discovery of multiple cardiac tumors. Antenatal cerebral ultrasound shows a normal appearance in affected fetuses. Eight fetuses with multiple cardiac tumors were studied with antenatal MRI with, in five cases, an abnormal appearance showing hyperintense subependymal and cortical nodules on T1-weighted images. Among the three remaining patients MRI was non-contributive in one due to movement artefact, one had abnormal postnatal MRI consistent with TS and one had a normal postnatal and clinical examination. We conclude that MRI is a valuable tool in making the diagnosis of TS in fetuses with multiple cardiac tumors.

Female↗

Desmoplastic supratentorial neuroepithelial tumours of childhood: imaging in 5 patients.

Desmoplastic neuroepithelial tumours are rare supratentorial neoplasms of infancy with a favourable prognosis. We characterised their imaging findings by reviewing the clinical and radiological reports of five affected children. The tumours were massive, predominantly cystic and with preferential frontal and parietal lobe involvement. The cystic component was in the white matter, with no communication with the ventricle. The solid part was superficially, abutting a meningeal surface, and showed intense contrast enhancement. A heterogeneous predominantly solid mass was observed in one patient. Thinning and deformation of the skull adjacent to the tumour was shown in four cases. Peritumoral oedema was absent or moderate. No calcification or haemorrhage were present. Angiography showed a tumour blush from the internal or external carotid arteries in one case each. Follow-up (3 months-9 years, mean 4.5 years) showed no recurrence.

Angiography↗

Embolisation of vascular lesions of the spinal column in childhood: a report of three cases.

We report three cases of embolisation of hypervascular vertebral lesions in children. We embolised two cases of osteoblastoma prior to surgery, and one thoracic vertebral haemangioma. The technique and clinical results are described. We conclude that embolisation of vascular lesions of the spinal column in children is useful preoperatively or to reduce pain in vertebral haemangiomas.

Child↗

Magnetic resonance imaging for diagnosis of Shwachman's syndrome.

Shwachman's syndrome is a rare disease characterized by the association of chronic diarrhea due to exocrine pancreatic insufficiency, metaphyseal dysostosis, and neutropenia. The diagnosis requires demonstration of lipomatosis, or fatty replacement of the pancreas, which is the typical pathological feature of the disease. Magnetic resonance imaging (MRI) was performed in 13 patients with exocrine pancreatic insufficiency, 7 with Shwachman's syndrome, 2 with Pearson's syndrome, 1 with normal sweat test later diagnosed as cystic fibrosis, and 3 without identified syndrome, and in 7 control children. Ultrasonography in the patients did not differentiate between atrophy and lipomatosis and could not be performed in 3. MRI visualized the pancreas in all. The same image was noted in all patients with Shwachman's syndrome with a normal-sized or enlarged pancreas, a hyperintense signal on T1- and T2-weighted image, and a null signal on short time inversion recovery (STIR)-weighted image, characteristic of fat. In all other patients, the findings were very different: The pancreas was a small structure surrounded with fat. In 1 patient without identified syndrome, the pancreas appeared to be partially replaced with fat. MRI is an excellent imaging technique to correlate the nature of a tissue and its radiological representation, especially fat, which gives a very typical signal. In our brief series of patients with Shwachman's syndrome, MRI had 100% positive predictive value in demonstrating lipomatosis. In atypical cases of pancreatic insufficiency in which some of the clinical features of Shwachman's syndrome are absent. MRI is an invaluable aid in the diagnostic procedure.

Adolescent↗