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Biomedical subjects

J F Chateil

Publications and source records attributed to J F Chateil.

At least 55 records · Page 3Linked to original sources
PubMed1997

Magnetization transfer imaging in vivo of the rat brain at 4.7 T: interpretation using a binary spin-bath model with a superLorentzian lineshape.

Proton magnetization transfer contrast (MTC) imaging, using continuous wave off-resonance irradiation, was performed on the rat brain in vivo at 4.7 Tesla. The observed MTC was studied in three different brain regions: the corpus callosum, the basal ganglia, and the temporal lobe. By systematically varying the offset frequency and the amplitude of the RF irradiation, the observed signal intensities for each region of interest were modeled using a system including free water and a pool of protons with restricted motions (R. M. Henkelman, X. Huang, Q. Xiang, G. J. Stanisz, SD Swanson, M. J. Bronskill, Magn. Res. Med. 29, 759 (1993)). Most of the relaxation parameters of both proton pools remained fairly constant for the three regions of interest, with a T2 value of about 9 micros for the immobilized protons, whereas the rate of exchange increased significantly from the temporal lobe to the corpus callosum. The optimal acquisition parameters for the improved MTC under steady-state saturation were found to be 2-10 kHz offset frequency and 500-800 Hz RF irradiation amplitude. Conversely, an irradiation amplitude of 3 kHz at an offset frequency of 12 kHz is required to minimize the direct effect of off-resonance irradiation. Such an approach could be extended to human brain imaging with the aim of characterizing tissue-specific disease.

Animals↗
PubMed1997

Cranial aneurysmal bone cysts presenting with raised intracranial pressure: report of two cases.

Aneurysmal bone cysts in the skull vault are reported in two patients 7 and 9 years old, who presented with vomiting and headaches caused by raised intracranial pressure. CT showed the cystic lesion in the diploë, with predominantly inward expansion. Fluid-fluid levels were seen on both CT and MRI; the latter also showed bleeding within the cyst. MR angiography showed compression of the superior sagittal sinus in the second case.

Bone Cysts, Aneurysmal↗
PubMed1997

18p monosomy with midline defects and a de novo satellite identified by FISH.

We report a girl with an 18p deletion and showing a total GH deficiency, a single central maxillary incisor, and a pituitary dysplasia. This suggests that del(18)(p) could be involved in pituitary dysplasia. We review the association between midline developmental defects and chromosome 18 anomalies. This case is due to a de novo satellite resulting from an unbalanced translocation t(18p;13p) identified by FISH. This is the first case of this cytogenetic mechanism in the 18p monosomy.

Child, Preschool↗
PubMed1997

[Encephalocraniocutaneous lipomatosis].

BACKGROUND: Encephalocraniocutaneous lipomatosis (ECL) involving the scalp and cerebellum was observed without asymptomatic expression. CASE REPORT: A seven-month-old infant presented with two soft subcutaneous hairless tumors of the scalp without any associated clinical anomaly. Neuroradiology explorations (radiography, CT-scan and MRI) showed a lipoma in the cerebellum linked with a occipital cutaneous lipoma through a bone defect. At the age of 3 years, the child remains healthy. DISCUSSION: ECL is a rare neurocutaneous disorder that consists of skin lipomas associated with various cerebral anomalies. ECL may occur as a circumscribed form of the Proteus syndrome, since a few ECL patients have associated manifestations of proteus syndrome as well as localized hypertrophy. However, minor forms of ECL are possible and may be compatible with normal life.

Brain Diseases↗
PubMed1996

[Superior sagittal sinus thrombosis in children during the first year of life: clinical aspects, imaging and development].

BACKGROUND: Thrombosis of the intracranial sinuses and veins may be septic or aseptic, and in the latter case are often due to alteration in hemodynamics. It may also be seen in young babies without known predisposing factors. PATIENTS: From 1988 to 1994, 11 children had cerebral venous thrombosis (longitudinal sinus) in the first year of their life. Their ages ranged from two days to 11 months. Transient seizures, lethargy, pseudo tumor cerebri were the first clinical symptoms. The presence of longitudinal sinus thrombosis was suggested by unenhanced CT scan, confirmed by colour doppler flow imaging and magnetic resonance angiography, with absence of blood flow in the longitudinal sinus. Repeated doppler flow imaging showed thrombus resolution within 3 weeks. Thrombosis was associated with predisposing factors in seven cases and appeared idiopathic in the four others. CONCLUSION: Diagnosis of longitudinal sinus thrombosis can be made more accurately and noninvasively by colour doppler flow and angio-MRI. Treatment with anticoagulants appears unnecessary and dangerous in idiopathic forms.

Female↗
PubMed1996

[Increasing frequency and diagnostic difficulties in intestinal stenosis after necrotizing enterocolitis].

BACKGROUND: Stenosis after necrotizing enterocolitis (NEC) has increased from 15 to 57% over the last 10 years in our unit. The aim of this study is to point out the difficulty of diagnosis and treatment, and search for factors explaining this increase. PATIENTS AND METHODS: From 1986 to 1991, 42 newborns had NEC, followed by intestinal strictures in 19 of them (57% of the 33 survivors). Data from these 19 patients were compared with those of the 14 without intestinal strictures. The 33 survivors were also compared with those of an earlier study including 25 NEC seen from 1979 to 1986. RESULTS: After medical treatment (n = 12), intestinal stenosis led to occlusion after three weeks, was located to both small and large intestine and was short and tight. After surgical treatment (n = 7), stenosis was shown by opacification before digestive anastomosis (n = 5) or revealed by occlusion (n = 2); it stayed on the colon, was long or multiple, requiring extensive resections. No difference could be found between data from patients with or without stenosis. Although newborns were actually more premature, the risk of stenosis was more frequent when newborns of same gestational ages and/or weights were compared. CONCLUSIONS: Intestinal stenosis is a frequent complication after NEC; its diagnosis is often difficult and requires extensive digestive resections. No clinical or therapeutic factor could be found to explain the actual increase in frequency.

Birth Weight↗
PubMed1996

[Acute torsion of an accessory spleen].

A case of acute torsion of an accessory spleen is reported. In a 15-year-old girl was admitted to hospital with acute abdominal pain. Ultrasonography showed a round, hypoechoic, solid mass. Computed tomography demonstrated a low-density mass with peripheral enhancement after intravenous contrast medium. These findings suggest the presence of a capsule. At laparotomy, the patient was found to have torsion and infarction of an accessory spleen. Sonographic and computed tomographic findings are discussed.

Acute Disease↗
PubMed1996

[Imaging of Erdheim-Chester disease].

Erdheim-Chester disease is a form of Histiocytosis which involves the adults and is distinct from Histiocytosis X. It is characterized by a constant diaphyseal and metaphyseal bone involvement predominating in the lower links. The diagnosis can readily be envisaged when the typical radiological findings are present. Bone involvement may be isolated and well tolerated, or can be associated with systemic involvement and a severe prognosis. We describe three cases of women aged 46, 50 and 73 years. One patient presented with isolated bone lesions, while the two others had a multiorgan localization. From the three cases and from an extensive review of the literature, we describe the spectrum of bone and visceral lesions that can be seen by imaging. The emphasis is put on lesions of the skeletal system, the retroperitoneum, the nervous system, and the pericardium. Furthermore, the relationships between Erdheim-Chester disease and Histiocytosis X are discussed.

Aged↗
PubMed1995

Infantile myofibromatosis.

An unusual case of infantile myofibromatosis with foci of calcifications was presented, with atypical age of onset and location. The radiological features of this tumor are not always evocative, and histological examination is necessary for diagnosis.

Actins↗
PubMed1995

Phenotypic variability in van der Woude syndrome.

The association of lower lip pits with cleft lip and/or palate defines the van der Woude syndrome (VWS). VWS has an autosomal dominant mode of inheritance wiht a high penetrance and a variable expression. A gene involved in the origin of VWS is linked to loci on chromosome 1q32-q41. The gene might be involved in the programmed cell death of neural crest derived cells. Other malformations have been associated with the syndrome (dental defects, syngnathia, limb abnormalities, popliteal webs...). We report 4 cases with VWS demonstrating the wide clinical variability. One case shows brain abnormalities that might be part of the clinical spectrum of VWS.

Abnormalities, Multiple↗
PubMed1994

[Agyria-pachygyria and pachygyria in children. Contribution of imaging].

BACKGROUND: Lissencephaly (agyria-pachygyria) is a defect in migration of cerebral neurons resulting in failure of cortical gyri to develop. Progress in imaging techniques improves its diagnosis. POPULATION AND METHODS: The files of 17 patients (ten boys and seven girls), aged 7 months to 16 years, were retrospectively studied. The clinical picture consisted of mental retardation (17 patients), seizures (eight patients), facial dysmorphia (seven patients), axial hypotonia (four patients). CT scan was performed in 16 cases and MRI with T1 and T2 weighted images in all 17. RESULTS: The CT scan identified pachygyria in 12 cases. Cerebral calcifications were seen in four cases. MRI detected typical changes in all 17 cases: thickened cortex and gyri, loss of cortical white matter interdigitations, lack of operculisation of the sylvian fissure. Pachygyria was generalized (six patients) or localized (11 patients). Associated abnormalities were dysgenesis of corpus callosum in three patients, cerebellar hypoplasia in one, deep grey matter heterotopia in one; hypersignal of the white matter was identified on T2 weighted images in five patients. CONCLUSION: MR imaging permits precise analysis of abnormalities secondary to a defect in neuronal migration.

Adolescent↗
PubMed1993

[Imaging of scoliosis].

The majority of scoliosis (80%) and especially the idiopathic scoliosis are simply investigated by plain films of the entire spine with erect frontal and lateral views, and supine frontal view at the initial examination. Repeated erect frontal views are sufficient for the follow-up. The important radiation dose (average of 1.2 mG for the frontal view and 2.2 mG for the lateral views) imposes to reduce the frequency of these radiographs. This radiological study allows: to separate non structural and structural curves; the identification and the measurement of a structural curve, discussion for its etiology, appraisal of its progressiveness, discussion of the operative or non operative treatment, and radiological follow-up. Modern imaging (C.T, C.T myelography, MRI) is indicated only in very particular cases: idiopathic scoliosis with neurological symptoms, congenital scoliosis with structural vertebral abnormalities, especially these with posterior arch abnormalities, and progressive scoliosis in spinal dysplasiae. Painful scoliosis are unusual. If pain is present consideration should be given for diagnosis of an underlying lesion. In this case a relevant strategy using modern imaging becomes useful and will be discussed.

Humans↗
PubMed1993

[Accessory thymus in cervical ectopy: apropos of a case].

Cervical tumors of thymic origin are considered to be uncommon lesions in the differential diagnosis of neck masses. They can be either cystic or solid. The authors present one case of solid cervical thymic tumor in a 2 month-old baby. The embryogenesis of the thymus explains the cervical location of these tumors. Theories of physiopathology are presented. The clinical presentation is variable and their nature is often recognized only upon surgery and preoperative pathologic examination. Some cases of thymoma and respiratory complications resulting from ectopic thymus have been described in the literature, so that total excision of the mass must be performed. This lesion may be more common than suggested in the literature.

Choristoma↗
PubMed1993

[Multicystic renal dysplasia with ectopic implantation of the ureter in boys. Apropos of 6 cases].

The prevalence of multicystic dysplastic kidney has increased since the development of antenatal ultrasound diagnosis. Even though, the rarity of symptomatic forms and case reports of spontaneous regressions antenatally or after postnatal ultrasound follow-up have reduced indications of nephrectomy which is less and less appropriate. However, discovery of ectopic ureteric implantation in boys makes certain additional investigations as intravenous pyelography, cystography and ultrasound, essential before making any therapeutic decision. Nevertheless, some cases remain undescriptible. In these cases, operative opacification of any patent ureter can provide more precise information about ureteric implantation. Lastly, only a dissection and resection as complete as possible of any patent ureter and pelvic cystic dilatation can prevent subsequent complications.

Child, Preschool↗
PubMed1992

[Ectasia of the umbilical recess during the antenatal period. 3 case reports].

Having found three cases of ectasia of the umbilical recess in the antenatal period we decided to review the embryology and the ultrasound of the anatomy of the portal system. We consider that this is a normal anatomic variant of the portal system because the lesion is asymptomatic and regresses spontaneously.

Congenital Abnormalities↗