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H Dufour

Publications and source records attributed to H Dufour.

At least 73 records · Page 4Linked to original sources
PubMed2001

[Central neurocytoma revealed by intraventricular hemorrhage. A case report and review of the literature].

A case of intraventricular tumor presenting with intraventricular hemorrhage in a 38-year-old man is reported. Initial symptoms were an acute onset of headache with projectile vomiting. CT-scan revealed intraventricular hemorrhage. Cerebral angiography did not show any vascular malformation. MRI study, performed initially and several days after, disclosed and confirmed the presence of an intraventricular mass. The patient was operated on via a transfrontal route, and a complete tumor removal was achieved. Pathological examination was consistent with a central neurocytoma. Two similar cases from the literature are discussed with respect to differential diagnosis and practical management considerations.

Adult↗
PubMed2001

[Burkitt lymphoma of the cavernous sinus. Apropos of a case].

Cavernous sinus lymphoma is a rare occurrence. We report a case of a 37-year-old woman who was admitted for an oculo-motor paresis and retro-orbital pain. CT scan and MRI disclosed a cavernous sinus tumor. A surgical biopsy was performed through a pterional approach and the histological diagnosis was a solitary primary Burkitt's lymphoma. Aggressive chemotherapy led to a complete and asymptomatic remission after a follow-up of 9 years. The mechanism of the primary localization in the cavernous sinus is discussed.

Adult↗
PubMed2000

Papillary glioneuronal tumour: clinicopathological and biochemical study of one case with 7-year follow up.

Among the mixed glioneuronal tumours, a new variant called papillary glioneuronal tumour has recently been delineated. A case occurring in a 23-year-old man is reported. The tumour was cystic with a mural nodule enhanced by gadolinium injection. It was located within the left parieto-occipital lobe. Surgical excision showed a greyish friable tumour with cystic areas. Histopathological examination revealed a pseudopapillary component comprising a single layer of regular cells, arranged around hyalinised vessels. These cells were immunoreactive with anti-glial fibrillary acidic protein and HNK1 antibodies. A neurocytoma-like component coexisted with round blind cells and focal fibrillary rosettes. These cells were immunostained by anti-neuron-specific enolase and anti-synaptophysin antibodies. Neither mitoses nor ganglioid cells were seen. HNK1, the three isoforms of NCAM, and the L1 adhesion molecule were detected by Western blot analysis. Ultrastructural study showed three different types of cells. The first contained gliofilaments, the second showed long processes with true synapses, and the third was poorly differentiated. However, all had identical nuclei and contained dense bodies. These findings suggest a common origin for the tumour cells derived from a bipotential neuroglial progenitor. As for other mature mixed neuroglial tumours, the prognosis is good. Our patient is free of disease 7 years after complete surgical treatment.

Adult↗
PubMed2000

Intracranial pseudolymphoma.

Intracranial pseudolymphoma is a rare tumor of the central nervous system. A 35-year-old woman presented with a frontal subcutaneous tumor. Magnetic resonance imaging revealed a left frontal meningeal tumor involving subcutaneous tissue without bone involvement. The mass was completely removed and the histological aspect of all tumor sections was that of a lymphoid hyperplasia with polyclonal proliferation. These findings were characteristic of pseudolymphoma defined as a hyperplasia of follicular and diffuse lymphoid type with assessment of its polyclonality by immunophenotyping on frozen sections, completed by molecular biology techniques.

Adult↗
PubMed2000

Centrifugal pumps and heparin-coated circuits in surgical treatment of giant cerebral aneurysms.

Giant cerebral aneurysms may be untreatable by conventional neurosurgical techniques. Early attempts to use circulatory assistance and deep hypothermia were abandoned due to hemorrhagic complications. More recently, interest in circulatory support for complex neurosurgical procedures has been renewed. A consecutive series of 8 patients were operated on for giant cerebral aneurysms with the combined use of deep hypothermia. The protocol included careful preoperative cardiovascular assessment, perfect intraoperative synergy between neurosurgical and cardiac teams, minimally invasive peripheral vascular access including two femoral vein (21 F) and single arterial (17 F) femoral cannulation, use of total Carmeda coating on BioMedicus pumps in closed circuits, and reduced heparinization without Protamine reversal. All cerebral aneurysms were successfully treated through deep hypothermia (15-18 degrees C) as assessed by intraoperative fluoroscopic controls and Doppler vascular assessment. Mean circulatory support time was 174.2 +/- 29.6 min. Circulatory arrest period was 20 +/- 12 min. All patients survived and were extubated within 48 h. No major deficit was observed clinically or on postoperative CT scan. No hemorrhagic complications occurred (mean transfusions was 2.2 blood units). This work supports an extensive use of heparin-coated surfaces for complex circulatory assist techniques, either for cardiac or extra cardiac complex procedures.

Adolescent↗
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

Gamma knife radiosurgery as a primary treatment for prolactinomas.

OBJECT: The purpose of this study was to estimate the efficacy of gamma knife radiosurgery (GKS) in controlling tumor growth and endocrinopathy associated with prolactinomas. METHODS: Between 1993 and 1997, 164 of 469 patients with pituitary adenomas treated by GKS harbored prolactinomas. The dose to the tumor margin ranged from 9 to 35 Gy (mean 31.2 Gy), and the visual pathways were exposed to a dose of less than 10 Gy. The mean tumor diameter was 13.4 mm. The mean follow-up time for 128 cases was 33.2 months (range 6-72 months). Tumor control was observed in all but two patients who underwent surgery 18 and 36 months, respectively, after GKS. Clinical cure was achieved in 67 cases. Clinical improvement was noted with a decrease in the hyperprolactinemia after GKS. Nonetheless, in 31 (29%) of 108 patients who were followed for more than 2 years no improvement in serum prolactin levels was demonstrated, although this could be normalized by bromocriptine administration after treatment. Nine infertile women became pregnant 2 to 13 months after GKS and all gave birth to normal children. There was no visual deterioration related to GKS. Five women experienced premature menopause. In these patients there was subtotal disappearance of the tumor and an empty sella developed. CONCLUSIONS: Gamma knife radiosurgery as a primary treatment for prolactinomas can be safe and effective both for controlling tumor growth and for normalization of prolactin hypersecretion. A higher margin dose (> or = 30 Gy) seemed to be associated with a better clinical outcome. Gamma knife radiosurgery may make prolactinomas more sensitive to the bromocriptine.

Humans↗
PubMed2000

[Neurofibromatosis type 2. Preliminary results of gamma knife radiosurgery of vestibular schwannomas].

BACKGROUND AND PURPOSE: The aim of this study was to assess tolerance and efficacy of gamma knife radiosurgery on vestibular schwannomas for patients affected with neurofibromatosis type 2. METHODS: Between July 1992 and December 1997, a gamma knife procedure was performed on 35 vestibular schwannomas affecting 27 patients (12 females and 15 males, mean age=27 years-old, range: 14-65). Fifteen of the patients were included in the Wishart subtype (severe form) and 12 patients in the Gardner subtype (mild form). This group of 27 patients represented 8,2% of the total group of vestibular schwannomas radiosurgically treated by our team. The mean tumor volume was 4,000 mm(3) (range: 400-14,400 mm(3)) and staging according to Koos classification was 9 stage 2 tumors (extension in the cerebellopontine angle), 19 stage 3 tumors (in contact with the brain stem or cerebellum) and 7 stage 4 tumors (compression of axial structures). The delivered mean marginal dose (50% isodose) was 13 Gy (range: 10-18 Gy). After the treatment, the mean clinical and radiological follow-up was 32 months (range: 6-70). RESULTS: Twenty six (74%) of the treated tumors were controlled by the treatment (15 stabilizations and 11 regressions of the tumor volume) at last follow-up. One microsurgical removal was required in a growing stage 4 tumor and in 2 cases of growing stage 3 tumors. Three post-radiosurgical facial nerve deficits (9%) were observed, 2 of them were transient. According to the Gardner and Robertson classification, classes I (good) and II (serviceable) hearing were preserved at last follow-up in 57% of the patients having the same hearing level prior to the gamma knife. CONCLUSIONS: Our experience confirms that tolerance of gamma knife radiosurgery compares favorably with microsurgery of bilateral vestibular schwannomas. This treatment should be restricted to small and medium growing tumors. Treatment strategy of neurofibromatosis type 2 patients should be planned by multidisciplinary experienced teams disposing of the whole armamentarium. A longer follow-up study is required to confirm the current results regarding the tumor control rate.

Adolescent↗
PubMed2000

[Occipital condyle fractures and clivus epidural hematoma. Case report].

A 47-year-old woman presented with a rare case of epidural hematoma of the clivus. The patient had bilateral occipital condyle fractures (a comminuted fracture on the right side, an avulsion fracture on left side and a lower clivus fracture). On admission the patient was tetraparetic with left abducens palsy. Preoperative imaging showed no atlanto-axial or occipito-atlantal dislocation. The patient was operated with a posterior approach. An occipital craniectomy with C1 laminectomy was achieved without atlanto-occipital fusion. Two years after the trauma, the patient had mild left hemiparesis but was able to walk normally. Head motion was normal, but just mildly decreased by pain in flexion and extension. Imaging control did not show any occipito-atlantal instability. We describe the imaging features allowing precise diagnosis and discuss the management of a rare entity: bilateral occipital condyle fractures and epidural hematoma of the clivus.

Accidents, Traffic↗
PubMed1999

Neuropsychological follow-up of twenty two adult patients after surgery for craniopharyngioma.

The optimal management of craniopharyngioma today remains an unconcluded debate. This prospective study examines the cognitive status and quality of life of 22 patients one year after surgery for craniopharyngioma. Pterional approach (5 left, 15 right) was used in 20 patients (90%), whereas two were operated on using a rhinoseptal approach. Neuropsychological examination was performed twelve months after the operation. For twelve patients, neuropsychological examination was performed before operation. The preoperative evaluation revealed that six patients had impaired neuropsychological testing with memory and frontal dysfunction. Four of these patients have no postoperative neuropsychological defect. After surgery, there were 5 patients in whom abnormalities could be detected on the extended psychometric assessment: two were severe (a Korsakoff's syndrome and a memory defect associated with an intellectual deterioration), and three moderate (recent memory defects with frontal dysfunction, isolated learning defects). Four patients of the 22 were not able to return to their pre-illness activity. The present evaluation emphasizes that a good quality of life and neuropsychological performance were maintained in the majority of patients. Preoperative frontal dysfunction is probably correlated to tumour location, and precisely to the interruption of the direct efferent projections from the frontal cortex to the hypothalamus. Postoperative alterations of neuropsychological function were noticed only in patients with pterional approach. These patients had a poor surgical outcome, preoperative neuropsychological defects or treatment combined with radiotherapy. The two patients who were operated on using a rhinoseptal approach had no neuropsychological deficit. But this surgical approach is best reserved for patients with smaller intrasellar tumours. Further studies are needed to evaluate the neuropsychological advantage of these different approaches.

Activities of Daily Living↗
PubMed1999

Trace lithium in mood disorders.

BACKGROUND: Variations in trace (endogenous) lithium exchanges have been postulated to play a role in the pathophysiology of affective diseases. This prospective study aimed to check whether plasma, erythrocytes and urine trace lithium levels were altered in mood disorders. METHODS: Trace lithium was determined by atomic absorption spectrophotometry in patients without mood stabilizing drugs or somatic diseases, hospitalized for bipolar affective disorders, major depressive episodes, and other psychiatric disorders with depressive features. Patients admitted for psychotic disorders without mood alterations and healthy volunteers served as controls. RESULTS: There were no differences in trace lithium status between the groups. Erythrocytes/plasma ratios appeared higher than described on therapeutic lithium (1.6+/-0.7, N = 199). LIMITATIONS: The study had sufficient power to detect clinically significant differences in whole body lithium handling between the groups. However, it did not address alterations of lithium exchanges across neuronal membranes or the blood-brain barrier. CONCLUSIONS: Alterations of membrane exchanges hypothetically associated with mood disorders are not reflected in plasma or erythrocytes trace lithium levels. The occurrence of mood disorders seems not to be related to abnormalities in endogenous lithium.

Antimanic Agents↗
PubMed1999

Cytogenetic study of 33 ependymomas.

Ependymomas are glial tumors. They constitute approximately 5-10% of intracranial tumors. Ependymomas are tumors which can recur. Predictive factors of outcome in ependymomas are not well-established. Karyotypic studies on ependymomas are relatively scarce, and no specific chromosomal change has been described in these neoplasms. We performed a cytogenetic study of 33 ependymomas, of which eight were recurrent tumors, to determine the type and incidence of cytogenetic changes.

Adolescent↗
PubMed1999

Expression of functional growth hormone secretagogue receptors in human pituitary adenomas: polymerase chain reaction, triple in-situ hybridization and cell culture studies.

We examined the expression of functional growth hormone secretagogue receptors (GHS-R) in a series of 30 human pituitary adenomas-six secreting GH, three GH-PRL, six prolactin (PRL), five adrenocorticotrophic hormone (ACTH), one thyroid stimulating hormone (TSH), four gonadotroph and five non-secreting adenomas. By reverse transcriptase polymerase chain reaction (RT-PCR), the coexpression of the two GHS-R isoforms (Ia and Ib) was found in all the GH-, GH-PRL- and PRL-secreting adenomas, and only in two out of three corticotroph, two out of four gonadotroph and one out of five non-secreting tumours. They were absent in the TSH-secreting adenoma. The PCR products of GHS-R Ia and Ib were identical in size to those from two normal pituitaries. PCR cloning and sequencing of isoforms performed in two somatotroph adenomas revealed only two single, silent base mutations. Triple in-situ hybridization showed colocalization of GHS-R mRNA with messengers of GH and PRL, conjointly or separately, in individual cells of somatotroph, mammosomatotroph, and lactotroph adenomas. The presence of GHS-R mRNA in cells expressing PRL mRNA is emphasized. In cultured cells from six somatotroph and two mammosomatotroph adenomas, the powerful GHS MK-0677 stimulated GH release in a dose-dependent manner, with maximal effect at 6 h. Contrarily, when GHRH was applied, only three somatotrophs and two mamosomatotrophs were stimulated. In the two mammosomatotrophs, the PRL response to MK-0677 and to GHRH was similar to the GH response. An homologous desensitization of the GHS-R and the GHRH receptor was observed 24 h after a first stimulation by a single dose of the corresponding agonist. Heterologous desensitization was not observed. Interestingly, MK-0677 also stimulated, in a dose-dependent way, the hormone release of cells from all tested lactotroph and corticotroph adenomas. The existence of a functional expression of GHS-R in somatotroph, mammosomatotroph, lactotroph and corticotroph adenomas rises the question of the role played by GHS-R in pituitary adenomas, particularly those not engaged in GH secretion.

Adenoma↗
PubMed1999

Metabolic and hemodynamic changes during recovery and tracheal extubation in neurosurgical patients: immediate versus delayed recovery.

UNLABELLED: Delayed recovery has been advocated to limit the postoperative stress linked to awakening from anesthesia, but data on this subject are lacking. In this study, we measured oxygen consumption (V(O2)) and plasma catecholamine concentrations as markers of postoperative stress. We tested the hypothesis that delayed recovery and extubation would attenuate metabolic changes after intracranial surgery. Thirty patients were included in a prospective, open study and were randomized into two groups. In Group I, the patients were tracheally extubated as soon as possible after surgery. In Group II, the patients were sedated with propofol for 2 h after surgery. V(O2), catecholamine concentration, mean arterial pressure (MAP), and heart rate (HR) were measured during anesthesia, at extubation, and 30 min after extubation. V(O2) and noradrenaline on extubation and mean V(O2) during recovery were significantly higher in Group II than in Group I (V(O2) for Group I: preextubation 215 +/- 46 mL/min, recovery 198 +/- 38 mL/min; for Group II: preextubation 320 +/- 75 mL/min, recovery 268 +/- 49 mL/min; noradrenaline on extubation for Group I: 207 +/- 76 pg/mL, for Group II: 374 +/- 236 pg/ mL). Extubation induced a significant increase in MAP. MAP, HR, and adrenaline values were not statistically different between groups. In conclusion, delayed recovery after neurosurgery cannot be recommended as a mechanism of limiting the metabolic and hemodynamic consequences from emergence from general anesthesia. IMPLICATIONS: In this study, we tested the hypothesis that delayed recovery after neurosurgery would attenuate the consequences of recovery from general anesthesia. As markers of stress, oxygen consumption and noradrenaline blood levels were higher after delayed versus early recovery. Thus, delayed recovery cannot be recommended as a mechanism of limiting the metabolic and hemodynamic consequences from emergence after neurosurgery.

Aged↗
PubMed1999

Quantitative and functional expression of somatostatin receptor subtypes in human prolactinomas.

Recently, it was demonstrated that somatostatin analogs preferential for the SSTR5 subtype suppress PRL release from prolactinoma cell cultures by 30-40%. These data supported the idea of somatostatin receptor subtype-specific control of PRL secretion in such tumors. The present study examines the quantitative profile of SSTRs messenger ribonucleic acid (mRNA) in 10 PRL-secreting tumors and correlates the expression with the ability of native somatostatins (SS14 and SS28), SSTR2 preferential analogs (octreotide and BIM-23197), and the SSTR5 preferential analog BIM-23268 to suppress PRL secretion. RT-PCR quantitative analysis showed a large predominance of SSTR5 mRNA [5648 +/- 1918 pg/pg glyceraldehyde-3-phosphate dehydrogenase (GAPDH)] vs. SSTR2 mRNA (148 +/- 83 pg/pg GAPDH). The SSTR1 transcript was also highly expressed in prolactinomas (1296 +/- 669 pg/pg GAPDH). SSTR5 mRNA expression correlated with PRL inhibition induced by both SRIF14 and SRIF28. Among the different analogs tested, only BIM-23268 produced inhibition of PRL release similar to that achieved with the native peptides. Its EC50 for PRL suppression was 0.28 +/- 0.10 nmol/L. No additive effects on PRL suppression were achieved by cotreatment of the tumor cells with SSTR2 and SSTR5 preferential analogs. In the same tumor cell cultures, quinagolide, a potent dopamine agonist, produced a dose-dependent inhibition of PRL with an EC50 at least 10 times lower than that of BIM-23268. Coincubation of quinagolide and BIM-23268, particularly in tumor cells resistant to dopamine agonist treatment, did not produce additive effects on PRL suppression. In conclusion, prolactinomas have a specific pattern of SSTR subtype mRNA expression (SSTR5 and SSTR1). SSTR5 expression is correlated to PRL regulation. These inhibitory effects are superimposable, at a higher concentration, to those of the dopamine agonists, but are not additive, particularly in the adenomas resistant to dopaminergic suppression of PRL release.

Adult↗
PubMed1999

An ultrarapid prognostic index in microprolactinoma surgery.

OBJECT: Prolactinomas account for approximately 40% of pituitary tumors. If the tumor does not exceed 10 mm at its largest diameter (microprolactinoma), the chances of definitive cure as a result of surgery alone vary from 62 to 89% depending on the series. Until now, however, there was no mechanism to predict whether total excision of a tumor had been accomplished. To improve the chances of total excision, we compared the peri- and postoperative kinetics of circulating prolactin (PRL) in patients judged to be cured and those not cured. METHODS: The pre-, peri-, and postoperative variations in blood PRL concentrations were determined using assays conducted at 10-minute intervals. Of the 36 patients included in the study, 27 were considered cured (resumption of a normal menstrual cycle within 6 months, PRL concentration at 9 days [mean +/- standard deviation 2.5+/-2.1 ng/ml] and 12 months [4.5+/-2.2 ng/ml] after the operation < 10 ng/ml and normally stimulated by metoclopramide and thyrotropin-releasing hormone [TRH]). Nine patients were not cured (PRL 20+/-15.7 ng/ml at 9 days after surgery, with no response to metoclopramide and TRH). The kinetics of PRL decrease in definitively cured patients were characterized by the following: 1) the initial slope of the curve decreased by at least 11% within the first 10 minutes after resection, and 2) immediate postoperative PRL concentrations were 20 ng/ml or less. CONCLUSIONS: The measurement of the kinetics of PRL decrease during surgery allows the chance of gross-total resection to be successfully predicted less than 25 minutes after excision of the adenoma. Provided an ultrarapid assay is available (the test used in the present study took < 15 minutes), this prognostic index would be useful to make a decision to continue the surgical procedure when the initial PRL slope is judged to be insufficient. Its use may also be extended to other pituitary tumors such as somatotropic adenoma and basophilic adenoma (Cushing's disease).

Adolescent↗
PubMed1998

Are juvenile pilocytic astrocytomas benign tumors? A cytogenetic study in 24 cases.

We performed a cytogenetic study on 24 pilocytic astrocytomas: 23 in children and 1 in a young adult. We observed 12 normal karyotypes. In 12 karyotypes with structural and/or numerical abnormalities, chromosomes 7, 8, and 11 were most frequently involved. One case recurred and presented chromosomal abnormalities (hyperdiploidy) in the first tumor and additional structural abnormalities in the second tumor. We believe that chromosomal abnormalities in pilocytic astrocytomas are frequent and indicate tumoral progression.

Adolescent↗