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Biomedical subjects

N Girard

Publications and source records attributed to N Girard.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Trigeminal neuralgia: results of microsurgical and endoscopic-assisted vascular decompression].

INTRODUCTION: Vascular compression of the Vth cranial nerve is the leading cause of trigeminal neuralgia. Microvascular decompression has been promoted by Jannetta since 1970. We used the minimally invasive retrosigmoid approach, with the complementary help of endoscopic procedure. OBJECTIVES: MRI results, surgical findings and pain relief were studied after endoscopic assisted microvascular decompression. MATERIAL AND METHODS: Between 1991 and 2000, 98 surgeries were performed on 79 patients unresponsive to medical treatment, after an average of 6 years from the onset of the disorder. The mean follow-up period after operation was 28 months. RESULTS: MRI predicted neurovascular conflict with sensitivity of 93.6% and specificity of 100%. Pain relief after surgery was complete in 69% of the cases, partial in 21%. Surgery was a failure in 6% of the cases and 4% of patients were lost. Complications were limited to 10% of CSF disorders but only 1% (1 patient) needed a surgical revision. CONCLUSION: Microvascular decompression, performed through a key-hole approach, without cerebellum retraction and with endoscopic assisted surgery, yields a low risk of morbidity, even in elderly patients, and could be considered acceptable causal treatment of trigeminal neuralgia.

Decompression, Surgical↗
PubMed2002

Clinical features and neuroradiological findings of mitochondrial pathology in six neonates.

OBJECTS: We hoped to itemize the clinical and neuroradiological features of six neonates with mitochondrial disorders. METHODS: We examined a case series of six neonates. The diagnosis of mitochondrial cytopathy was made on the basis of spectrophotometric measurements of respiratory chain enzyme activities in skeletal muscle biopsy specimens. Magnetic resonance (MR) imaging was performed in all cases. CONCLUSIONS: The antenatal onset in five cases and the lack of any symptom-free interval are suggestive of fetal expression of the disease. No specific symptoms were found: arthrogryposis congenita multiplex in one, progressive hepatocellular dysfunction in three, encephalomyelopathy and cardiomyopathy in four. Complex I deficiency was found in three patients, while one patients had a defect of complex IV and the last a combined defect of complexes I and IV. Neuroradiological findings were either cerebral atrophy or white matter abnormalities of the brain stem in all cases but one and gave additional information, because clinical symptoms are not quite specific. The combination of clinical and MRI findings in neonatal cases can rule out hypoxic ischemic encephalopathy, which suggests an additional screening method to look for mitochondrial disorder.

Brain↗
PubMed2002

[Early cerebral MRI in preterm infants: correlations with EEG and outcome].

AIM OF THE STUDY: Assess the potential benefits of performing an early cerebral MRI to evaluate the gravity of cerebral lesions among premature neonates at risk of neurologic sequels and establish correlations between EEG findings, abnormal neuroimaging findings and neurodevelopment. METHODS: A MRI was performed in 34 premature newborn babies with abnormal neurological clinical signs, and/or with two abnormal EEG and/or with two abnormal cerebral ultrasound scans. The mean age and the adjusted age of our population were 5 weeks (range 1-11 weeks) and 35 weeks of adjusted age (range 29-40 weeks) respectively. The neuroimaging findings were correlated to the results of three EEGs (recorded before 15 days old, between 15 days and one month old, and after the first month of life) and to neurodevelopment. RESULTS: Two statically significant correlations were found between: 1) the severity of brain injuries observed in MRI and the results of the latest EEG (sensitivity 100%, specificity 60%), 2) the severity of brain injuries observed in MRI and abnormal neurodevelopment (sensitivity 75%, specificity 80%). There was no correlation between the abnormal development and the results of EEG recordings. CONCLUSION: Early cerebral MRI is justified in a selected premature population. It is useful for the diagnosis, the evaluation of the severity of brain injury and for the management of these children. The correlation with EEGs traces allows the detection of the majority of prematures babies that will develop sequels.

Brain Diseases↗
PubMed2002

[Adenocarcinoma of the endolymphatic sac in children. A case report].

We report a case of an adenocarcinoma of the endolymphatic sac in a 13 years old child, which was fortuitously discovered at the time of radiological investigation of growth delay. Arising from the end of the endolymphatic sac, this rare tumour shares a similar clinic expression with other cerebellopontine angle pathologies. Radiological investigation reveals a moth eaten appearance to the posterior temporal bone and specific bony inclusions. With MRI there is an intense and/or intermediate signal on T1, a hyper signal on T2 and T1 enhancement with injection of gadolinium. Treatment is surgical and local recurrences are not uncommon. After histological confirmation, a search for Von Hippel-Lindau disease is mandatory because this tumour is not exceptional among this subset of patients. Diagnosis and therapeutic criteria will be highlighted by our case and a review of the literature.

Adenocarcinoma↗
PubMed2002

[Craniopharyngioma in children: MRI study of 43 cases].

BACKGROUND AND PURPOSE: Craniopharyngiomas are intra-cranial tumors, relatively frequent in children, expanding in the pituitary stalk axis, from the third ventricle to the sphenoid body. Plain films and CT scan generally show a calcified lesion, deforming the sella turcica. MRI improves tumor description and topographic and structural analysis of the lesion. The aim of this study is to analyze the MRI aspect of craniopharyngiomas in a pediatric population and to correlate findings with surgical data. METHODS: MR and CT studies of 43 pediatric cases of histology-proven craniopharyngiomas were reviewed retrospectively. Tumor emergence, extensions and signal on different sequences were recorded. We searched for radio-surgical correlations. RESULTS: Craniopharyngiomas can be classified into two groups: intra-sellar tumors and third ventricle floor tumors (infundibulum and tuber cinereum). Preferential routes of extension are observed in each group correlated with consistency (cystic and/or solid). Surgical data confirmed these results. CONCLUSIONS: MRI is crucial for the pre-therapeutic evaluation of craniopharyngiomas allowing not only a detailed description of the tumor but also guiding therapeutic decisions. This series demonstrated that craniopharyngiomas exhibit two different types of localization and behavior. Embryonic development of the tumor explains the topographical differences.

Adolescent↗
PubMed2001

Schizencephaly: correlation between the lobar topography of the cleft(s) and absence of the septum pellucidum.

The bipolar defects observed in schizencephalies-clefts in the hemispheric mantle on the one hand, absent septum pellucidum on the other--without any anatomic or functional continuity suggest that there is some sort of common specific vulnerability of both structures. A study of the correlation between lobar location of the clefts and involvement of the septum pellucidum was undertaken, considering the hypothesis that the septum pellucidum is the portion of a "medial medullary velum" that corresponds to the frontal lobe, while the psalterium would correspond to the parieto-occipital lobe and the fimbria corresponds to the temporal lobe. This retrospective study of 16 cases of schizencephaly properly investigated by MR discloses a perfect correlation, all cases with absent septum pellucidum having clefts into the frontal lobe, all cases with present septum pellucidum having clefts in the parietal, temporal, and occipital lobes, and only the few instances (3 cases) of overlapping findings being characterized by clefts in the central area, where the distinction between posterior frontal and anterior parietal lobes is uncertain because of the cortical dysplasia related to the clefts. Partial defects of the septum also proved to correlate closely, topographically, with the location of the clefts. Therefore, the facts confirm a segmental organization of the mantle and septal defects, suggesting a developmental rather than a destructive mechanism, which could at least be related to a segmental pattern of selective vulnerability.

Brain Damage, Chronic↗
PubMed2001

Fetal brain MR imaging.

In the past 10 years, improvements in MR imaging and faster imaging techniques have dramatically increased the use of in-utero fetal brain MR imaging. Challenging abnormalities now can be diagnosed prenatally through a careful analysis of morphology and signal changes. Using illustrations of normal brain development as a starting point, this article illustrates and discusses major brain malformations and specific morphologic changes, destructive lesions, and isolated ventriculomegalies, and the advantages and disadvantages of T1 and T2 sequences are provided.

Brain↗
PubMed2001

Neuroimaging of epilepsy in children.

Epilepsy is, above all, a pediatric disease. The electroclinical expression of epilepsy depends on several factors, including the presence of a subjacent brain anomaly and the age of the child. Genetic, congenital, and perinatal disorders account for most of the cases. MR imaging should identify any abnormality of the brain, in order to understand the condition and, in selected cases, to be able to treat the patient surgically.

Brain↗
PubMed2000

[Hypoxic-ischemic encephalopathy in the full-term newborn. Contribution of electroencephalography and MRI or computed tomography to its prognostic evaluation. Apropos of 26 cases].

OBJECTIVES: Perinatal asphyxia complicated by hypoxic ischemic brain injury still remains the source of neurological lesions often serious and definitive. A major aim of neonatologists is to appreciate the severity of the hypoxic ischemic brain injury in the first days of life and to evaluate the forecast. The purpose of this work is to establish a relation between clinical signs, EEG, neuroimaging (MRI and CTS) and neuro-development. MATERIALS AND METHODS: 26 neonates from paediatric resuscitation unit (Hospital North, Marseille) were enrolled in a retrospective study since February 1994 to December 1997. All the newborns had at least one anamnestic criteria of perinatal asphyxia, an early electroencephalogram in the first two days of life and another between the third and the seventh day of life, and neuroimaging in the first 15 days of life: CTS in five cases and MRI in 21 cases. RESULTS: There was a good electro-clinic (P: 0.01) and prognostic (P: 0.03) correlation in patients within stage 3 of the "Sarnat classification". In the stage 2, the EEG did not provide valuable information about severity of the injury, and neuroimaging (especially MRI) allowed better prognosis. Diffuse brain injury or lesions of basal ganglia in MRI were associated, independently of clinical settings and EEG tracings, with a poor neurodevelopmental outcome (P: 0.02). The MRI was diagnostic in four cases of congenital encephalopathy complicated with neonatal suffering. CONCLUSION: Our study confirms the interest of the association of clinical settings, EEG tracings and MRI in the diagnosis and the prognostic of the hypoxic-ischemic encephalopathy in term neonate.

Disease Progression↗
PubMed2000

Therapeutic efficacy of intralesional 131I-labelled hyaluronectin in grafted human glioblastoma.

The grafted human glioblastoma cell CB109 was used as a model for intralesional therapy with 131I-labelled hyaluronectin glycoprotein (131I-HN).131I-HN bound specifically to in situ hyaluronic acid (HA), a main component of the extracellular matrix which is involved in tumour invasion. Labelling experimental conditions were determined and, finally, 25 microCi/microgHN, 1 microg chloramine-T/microgHN and a 60-s stirring period provided a 131I-HN preparation with an optimal affinity for HA (64% compared to unlabelled HN). Following intratumoral injection, 131I-HN was retained with a limited diffusion outside the tumour. On day 4 the radioactivity concentrated in the tumour was still 25 times greater than that in the liver, spleen and kidneys combined. For therapeutic assays, 65 microCi 131I-HN was injected into the tumour, resulting in a delivery of 6.8 Gy over a 7-day period. Controls received unlabelled HN, heat-inactivated HN, a mixture of inactivated HN plus free 131I or no treatment (six animals per group). Tumour volumes were evaluated every second day from treatment day and the rate of tumour growth was expressed as a ratio of tumour size at time intervals to the tumour size at the time of injection. Growth curves were compared: heat-inactivated with or without free 131I had no anti-tumour effect. Unlabelled HN-injected tumours had a slightly slower growth rate than untreated tumours (p < 0.02) and growth rate of 131I-HN-injected tumours was much lower (p < 0.00002). A pronounced inhibitory effect with intralesional 131I-labelled HN injection resulted from a combination of a) blockage of HA, a proliferation facilitating factor, and b) local irradiation of tumoral tissue, while uptake in normal tissues was minimized.

Animals↗
PubMed2000

Markers of tumor invasion are major predictive factors for the long-term outcome of corticotroph microadenomas treated by transsphenoidal adenomectomy.

OBJECTIVE: To assess the postsurgical outcome of patients with corticotroph microadenomas and to define predictors of the long-term outcome, with special emphasis on markers of tumor extension. DESIGN: Prospective study of 53 corticotroph microadenomas treated by enlarged adenomectomy. Patients followed for at least 2 years were classified into two groups: those in long-term remission and uncured patients (immediate failures and recurrences). Pre-, per- and postoperative parameters were analyzed as predictors of the long-term outcome. METHODS: Baseline hormone assessments were performed preoperatively, 8 days after surgery and every 6-12 months thereafter. Pituitary magnetic resonance imaging (MRI) allowed analysis of possible tumor extension to adjacent structures. Apparent completeness of the surgical removal was determined, and fragments labeled either 'tumor' or 'surrounding pituitary tissue' were submitted to serial sectioning. RESULTS: Immediate control of hypercortisolism was achieved in 43/53 patients (81%). However, later recurrences were observed in five patients (9%). Preoperative MRI showed tumor extension into adjacent structures with good specificity (91%) for prediction of surgical failure. Evidence of local invasion at surgery was also significantly predictive of the long-term outcome. A corticotroph adenoma was found at histological examination in 96% of the patients, and 26% had irregular limits, a feature significantly correlated with a poor outcome. Immediate postoperative plasma cortisol did not allow discrimination between long-term remissions and recurrences. CONCLUSION: Surgical failure was best predicted by signs of tumor 'invasiveness' at MRI, confirmed by peroperative examination and histology.

Adenoma↗
PubMed2000

Normal outcome after prenatal diagnosis of thrombosis of the torcular Herophili.

We report a case of prenatal diagnosis of thrombosis of the torcular Herophili. Detection at 22 weeks' gestation by ultrasound scan of an anechoic mass located immediately above the tentorium led to magnetic resonance imaging (MRI) being performed at 28 weeks which established the diagnosis of an isolated thrombosis of the torcular Herophili. MRI remained stable throughout pregnancy, and postnatal MRI confirmed the diagnosis at 2.5 months of age. The child is now 16 months old and developing normally.

Adult↗
PubMed2000

Grandpa's radical neck surgery: a historical memory.

This article is a professional and personal stroll down memory lane. The sister authors investigated one of the first radical neck procedures for cancer, performed in the early 1950s on their grandfather. The historical Operating Room Nurse role is briefly reviewed, and some of the effects of the surgery on the family are discussed. The surgeries today on ears, nose, and throat would not be possible without the brave pioneer patients, physicians, and nurses of the past.

Head and Neck Neoplasms↗
PubMed1999

Human breast-cancer metastasis formation in a nude-mouse model: studies of hyaluronidase, hyaluronan and hyaluronan-binding sites in metastatic cells.

Few animal models are available to study metastasis formation. The purpose of the present study was to obtain a useful model of metastasis formation in nude mice in an attempt to analyze the stroma reaction and in particular the production and the expression of hyaluronan (HA), hyaluronidase, and HA-binding sites by cultivated cells, and HA and hyaluronectin (HN) in the invasive areas of tumors. Nude mice were subjected to i.p. injections of several human cancer cell lines (PLC/PRF/5, HepG2, CB 191, CB 193, PC3, CAL 51, SA 87 and SA 98), and formation of metastases was analyzed in different organs (lung, liver, kidney, spleen and axillary nodes) by immunohistochemical techniques. CAL 51, a breast-cancer-metastasis-derived cell line with a normal karyotype, produced i.p. tumors in 75% animals and metastases in 90% animals (detected in the liver and axillary nodes). Two modes of invasion by CAL 51 cells were observed in the liver: one, direct, from the surface of the liver and the other, indirect, via the bloodstream. HA and HN were strongly expressed at the invasion areas. A cell line derived from hepatic metastasis of CAL 51 (HMD CAL 51) presented an abnormal karyotype. HMD CAL 51 produced more hyaluronidase (12-fold) and HA (10-fold) and expressed more CD44 (1.6-fold) and other HA-binding sites (9.5-fold) than the established cell line CAL 51. Our results show that i.p. injection of the CAL 51 cell line into nude mice provides a useful model of metastasis formation. The passage of the CAL 51 cells from the primary state to the metastatic state was characterized by a dramatic increase of HA and hyaluronidase production, and expression of HA, HN and HA-binding sites.

Animals↗
PubMed1999

Hyaluronectin secretion by monocytes: downregulation by IL-4 and IL-13, upregulation by IL-10.

Hyaluronectin (HN) is a component of the extracellular matrix of connective tissue and is particularly associated with tumour inflammatory and connective stroma reaction, where it co-localizes with hyaluronic acid (HA). The HN/HA ratio has been suggested to be involved in tumour aggressivity and in the atherosclerosis process. IL-10 has also been described in atherosclerotic lesions and in cancer. HN production was therefore investigated in vitro in peripheral blood monocyte cell (PBMC) cultures, with and without bacterial lipolysaccharide (LPS) or interleukins (ILs) in the medium. HN was characterized in monocytic cell cytoplasm and in culture supernatants. Anti-IL-10 antibody suppressed the LPS-stimulating effect on HN production. HN synthesis rate was greatly increased in IL-10-activated cultures while IL-4 and IL-13, two other anti-inflammatory ILs, decreased HN release. In the presence of IL-10, the IL-4 or Il-13 inhibitory effect on HN synthesis was reversed. The results support the view that intratumoral release of IL-10 by monocytes may induce local production of HN. In conjunction with the known ability of HN to bind to HA, which is a cell migration and tumour invasion facilitating factor, and to inhibit HA-induced angiogenesis, our findings suggest that HN may modulate the effect of HA on atherosclerosis, angiogenesis and cancer development.

Antibodies↗
PubMed1999

The pitfall of silent neurosarcoidosis.

Sarcoidosis in childhood is seldom reported. Most cases are observed in older children and preadolescents as bilateral pulmonary disease and eye lesions. Arthritic features are more likely to be observed in infants and children younger than 4 years of age who do not develop pulmonary disease. Neurosarcoidosis is exceptional in this age group and seldom suspected when the neurologic symptoms are present. The authors report a pediatric patient with systemic sarcoidosis who developed a severe but silent neurologic involvement. Numerous masslike lesions were discovered on systematic cranial magnetic resonance imaging. The authors recommend a complete screening of extrapulmonary manifestations in children with sarcoidosis. The proper management of patients with incidentally discovered neurosarcoidosis has yet to be established.

Brain Diseases↗