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J Brotchi

Publications and source records attributed to J Brotchi.

At least 37 records · Page 2Linked to original sources
PubMed2001

The Zeiss-MKM system for frameless image-guided approach in epidural motor cortex stimulation for central neuropathic pain.

OBJECT: Twelve patients (seven female, and five male, mean age 55.6 years) suffering from refractory central (ischemic/traumatic [eight cases]) and neuropathic pain (trigeminal neuropathy [four cases]) underwent surgery for the implantation of an epidural motor cortex stimulation (MCS) device in which the authors used a frameless neuronavigation system, the Zeiss-MKM microscope. METHODS: The authors assessed the spatial accuracy of the neuronavigation system and its potential contribution to improve the quality of targeting pain. In these patients, the positions of the central sulcus, defined by stereotactic magnetic resonance MR imaging, intraoperative somatosensory evoked potentials (SSEPs) and subdural visual verification, were correlated into the stereotactic neuronavigation planning procedure. The mean spatial accuracy of distance between (MR) imaging-defined and actual central sulcus was 2.4 mm (range 5-10 mm). The intraoperative SSEPdefined central sulcus was close to that defined by MR imaging (mean distance 6.4 mm). Although very precise, intraoperative SSEP recordings were impaired by artifacts and wave attenuation in six of the 12 patients. Stereotactic correlations between anatomical and functional data in the navigation system corrected final targeting in 10 of 12 cases. Pain relief was obtained in eight patients. Indeed, inappropriate targeting probably explains the reported variable success rate of MCS and certainly underestimates the actual efficacy. CONCLUSIONS: Since intraoperative SSEP monitoring has, for many years, been considered the standard procedure to approach motor target, the development of an accurate stereotactic image guidance system could help to increase the efficacy of MCS on the alleviation of pain. The excellent spatial accuracy provided by the Zeiss-MKM navigation system allows precise data correlations that represent a remarkable means to validate functional MR imaging as an alternative to SSEP. The authors believe that developing stereotactic image guidance with such a navigation system could improve the success rate of MCS.

Deep Brain Stimulation↗
PubMed2001

Molecular characterization of cell substratum attachments in human glial tumors relates to prognostic features.

Glioma cell attachments to substratum play crucial roles in the invasion by glioma cells of normal brain tissue. These attachments are mediated through interactions between extracellular matrix (ECM) components, integrins, focal adhesion-linked molecules, and the actin cytoskeleton. In the present study, we investigate the molecular elements involved in cell substratum attachments in human glial tumors and their potential relationships to prognostic features. We used 10 human glioma cell lines, for which we characterized glial differentiation by means of quantitative RT-PCR for nestin, vimentin, and GFAP mRNA. We quantitatively determined the amounts of laminin, fibronectin, vitronectin, and thrombospondin secreted by these glioma cell lines in vitro, as well as the amount of each of the eight beta integrin subunits and the adhesion complex-related molecules, including talin, vinculin, profilin, zyxin, alpha-actinin, paxillin, and VASP. After quantification of the levels of migration and invasion of these 10 cell lines in vitro and, through grafts into the brains of nude mice, of their biological aggressiveness in vivo, it appeared that the levels of the beta 5 integrin subunit and alpha-actinin were directly related to biological aggressiveness. These experimental data were clinically confirmed because increasing immunohistochemical amounts of the beta 5 integrin subunit and alpha-actinin were directly related to dismal prognoses in the case of astrocytic tumors. In addition, we show that the beta 4 integrin subunit are expressed significantly more in oligodendrogliomas than in astrocytic tumors. A potential role for the beta 8 integrin subunit in glioma cell substratum attachments is also emphasized.

Actinin↗
PubMed2001

Intracranial meningiomas revealed by non-traumatic subdural haematomas: a series of four cases.

OBJECTIVE: A review of the literature shows 33 cases of ipsilateral subdural haematomas (SDH) associated with meningiomas. We suggest that physiopathological mechanisms could be primary haemorrhages from abnormal vessels in the tumours and the opening of the intratumoral haematomas into the subdural space. Our working hypothesis relies on a series of 300 meningiomas operated upon in our department since 1990; of these, 4 were revealed by SDH. CLINICAL PRESENTATION: The four patients surgically treated in our department had developed a progressive impairment of consciousness. There was no history of trauma, blood dyscrasia or anticoagulant therapy. After diagnosis, the SDH was drained, and the meningeal tumour was totally resected once it had been discovered. In one case, the presence of a tumour was demonstrated by magnetic resonance imaging (MRI) performed only after the evacuation of a recurrent SDH. INTERVENTION: In each case, an acute SDH showing signs of recent bleeding was evacuated. The meningeal tumour discovered proved to be the source of the haemorrhage because of the numerous fresh blood clots both around and inside it. HISTOLOGY: In the four cases histology showed fresh intratumoral haemorrhages (ITH), large blood vessels with thin endothelial linings and haemosiderin deposits. In this review, SDH is associated with other haemorrhage sites in 24 of 37 cases (33+our 4 cases). ITH was present in 14 cases (40%). CONCLUSION: The treatment should consist of the extirpation of the meningioma at the same time as the evacuation of the haematoma. If primary ITH from abnormal vessels is the source of SDH, complete meningioma resection should prevent the recurrence of SDH. Subdural membranes and haematomas should therefore be inspected for their intrinsic pathology, especially when there is no history of trauma.

Aged↗
PubMed2001

Galectins are differentially expressed in supratentorial pilocytic astrocytomas, astrocytomas, anaplastic astrocytomas and glioblastomas, and significantly modulate tumor astrocyte migration.

Galectins, a family of mammalian lectins with specificity to beta-galactosides, are involved in growth-regulatory mechanisms and cell adhesion. A relationship is assumed to exist between the levels of expression of galectins and the level of malignancy in human gliomas. A comparative study of this aspect in the same series of clinical samples is required to prove this hypothesis. Using computer-assisted microscopy, we quantitatively characterized by immunohistochemistry the levels of expression of galectins-1, -3 and -8 in 116 human astrocytic tumors of grades I to IV. Extent of transcription of galectins-1, -3, and -8 genes was investigated in 8 human glioblastoma cell lines by means of RT-PCR techniques. Three of these cell lines were grafted into the brains of nude mice in order to characterize in vivo the galectins-1, -3 and -8 expression in relation to the patterns of the tumor invasion of the brain. The role of galectin-1, -3 and -8 in tumor astrocyte migration was quantitatively determined in vitro by means of computer-assisted phase-contrast videomicroscopy. The data indicate that the levels of galectin-1 and galectin-3 expression significantly change during the progression of malignancy in human astrocytic tumors, while that of galectin-8 remains unchanged. These three galectins are involved in tumor astrocyte invasion of the brain parenchyma since their levels of expression are higher in the invasive parts of xenografted glioblastomas than in their less invasive parts. Galectin-3, galectin-1, and to a lesser extent galectin-8, markedly stimulate glioblastoma cell migration in vitro. Since bands for the transcripts of human galectins-2, -4 and -9 were apparently less frequent and intense in the 8 human glioblastoma cell lines, this system provides an excellent model to assign defined roles to individual galectins and delineate overlapping and distinct functional aspects.

Adolescent↗
PubMed2001

Positron emission tomography with injection of methionine as a prognostic factor in glioma.

OBJECT: Positron emission tomography with L-[methyl-11C]methionine (MET-PET) provides information on the metabolism of gliomas. The aim of this study was to determine the predictive value of MET-PET in the treatment of patients with gliomas. METHODS: Since 1992, 85 patients with a World Health Organization (WHO) classification-verified glioma underwent PET studies in which MET was injected before (74 cases) or after treatment (11 cases). Analysis of PET data was conducted by the same investigator using two scales: a qualitative visual grading scale and a quantitative scale (ratio between tumor uptake and normal brain uptake, classified on a seven-level scale). Uptake of MET was present in 98% of gliomas. The investigator judged this uptake to be moderate to very high based on visual inspection (qualitative scale). For all grades of gliomas, a visual grade of 3 was statistically associated with a shorter patient survival period (p < 0.005). The tumor/normal brain uptake ratio was significantly influenced by the histological grade of the tumor. A statistically poor outcome was demonstrated when this ratio was higher than a threshold of 2.2 for a WHO Grade II tumor and 2.8 for WHO Grade III tumor. For Grade II and III tumors, oligodendrogliomas had a higher uptake of MET than astrocytomas. CONCLUSIONS: Uptake of MET was present in 98% of the gliomas studied. A high uptake is statistically associated with a poor survival time. The intensity of MET uptake represents a prognostic factor for WHO Grade II and III tumors considered separately.

Adult↗
PubMed2000

Statistical parametric mapping of regional glucose metabolism in mesial temporal lobe epilepsy.

We investigated statistical parametric mapping (SPM) use for positron emission tomography (PET) with [(18)F]fluorodeoxyglucose (FDG) data analysis in mesial temporal lobe epilepsy. The study involved 14 patients with temporal lobe epilepsy ultimately treated by anterior temporal lobectomy. Surgical outcome in terms of seizure control was favorable in 12 patients. Two different SPM approaches were designed to analyze each FDG-PET scan: a direct comparison with a control group (n = 27) and a search for significant interhemispheric asymmetry considering the asymmetry existing in the control group. Statistical inference was performed, first, without correction for multiple comparisons (making the hypothesis of temporal hypometabolism) and, second, after correction for multiple comparisons. Search for temporal interhemispheric asymmetry under the hypothesis of temporal hypometabolism was the most reliable SPM approach: hypometabolism was identified on the side chosen for resection in most cases (sensitivity, 71%; specificity, 100%) and was predictive of favorable postsurgical outcome in 90% of the patients. There was no false-positive result within the control group using this approach. After correction for multiple comparisons, SPM also identified in some patients temporal hypermetabolic areas as well as extratemporal cortical and subcortical hypometabolic areas on the side of resection but also on the contralateral side. In a further step, SPM was used for a group analysis of patients with favorable outcome after reversing scans when needed to set an identical lateralization in all patients. This analysis identified multiple ipsilateral temporal and extratemporal hypometabolic regions; when temporal metabolic changes were specifically assessed, the contralateral mesiotemporal region was found hypermetabolic, possibly as a manifestation of compensatory mechanisms in the presence of a unilateral epileptogenic lesion.

Adolescent↗
PubMed2000

FDG-PET as a prognostic factor in high-grade astrocytoma.

BACKGROUND: The prognostic value of the metabolic status of cerebral gliomas determined by positron emission tomography with [18F]-fluoro-deoxy-D-glucose (FDG-PET) has been established in populations with a mixture of grades 2, 3 and 4 gliomas, but remains uncertain when only malignant gliomas are considered (grade 3 and 4). METHODS: FDG-PET performed in 30 patients with anaplastic astrocytoma (grade III) and 61 patients with glioblastoma (grade 4) were classified according to a metabolic grading. The uptake of FDG was lower in the tumor compared to white matter (WM) in grade 1 (4 glioblastoma, 4 anaplastic astrocytoma), it was intermediate between WM and cortex in grade 2 (20 glioblastoma, 22 anaplastic astrocytoma), and it was superior to cortex in grade 3 (38 glioblastoma, 4 anaplastic astrocytoma). RESULTS: Kaplan-Meier survival curves were similar in patient with grades 1 and 2, but were significantly worse (p = 0.007) in grade 3. In multivariate analysis considering age, pathological grade (anaplastic astrocytoma versus glioblastoma), and metabolic grades, the metabolic grade did not appear to be an independent prognostic factor. When anaplastic astrocytomas and glioblastomas were considered separately, metabolic grade is of predictive value only in the group of glioblastomas. CONCLUSION: In malignant gliomas, metabolic grading determined by FDG-PET was not superior to the pathological grading for survival prediction. Still, it remains of predictive value when applied to malignant gliomas histologically classified as glioblastoma.

Adolescent↗
PubMed2000

Differential expression of S100 calcium-binding proteins characterizes distinct clinical entities in both WHO grade II and III astrocytic tumours.

The computer-assisted microscopic analysis of Feulgen-stained nuclei enabled us to identify two subgroups of astrocytomas (WHO grade II) and two subgroups of anaplastic astrocytomas (WHO grade III) with significantly distinct clinical outcomes (Decaestecker et al. Brain Pathol 1998; 8: 29-38). The astrocytomas labelled in the present study as typical (TYP-ASTs) behaved clinically like real astrocytomas while atypical astrocytomas (ATYP-ASTs) behaved similarly to anaplastic astrocytomas. The anaplastic astrocytomas that we labelled as typical (TYP-ANAs) behaved clinically like anaplastic astrocytomas while atypical ones (ATYP-ANAs) behaved like glioblastomas. In the present study, we investigate whether some biological characteristics could be evidenced across these four groups of TYP- and ATYP-ASTs and TYP- and ATYP-ANAs. The data show that the levels of expression (immunohistochemically assayed and quantitatively determined by means of computer-assisted microscopy) of vimentin, the glial fibrillary acidic protein and the platelet-derived growth factor-alpha did not differ significantly across these four groups of astrocytic tumours. The level of cell proliferation (determined by means of both the anti-proliferating cell nuclear antigen and the anti-MIB-1 antibodies; P < 0.001 to P < 0.0001) differed very significantly between the astrocytomas and anaplastic astrocytomas, but not between the typical and atypical variants identified in each group. In sharp contrast, the levels of expression of the S100A3 and S100A5 proteins differed markedly in the solid tumour tissue in relation to the astrocytic tumour types and grades. In addition, while the levels of expression of S100A6 did not change in the astrocytic tumour tissue in relation to histopathological grade, the levels of expression of this S100 protein (but not those of S100A3 and S100A5) differed markedly in the blood vessel walls according to whether these vessels originated from low- or high-grade astrocytic tumours.

Adult↗
PubMed2000

Combined magnetic resonance imaging- and positron emission tomography-guided stereotactic biopsy in brainstem mass lesions: diagnostic yield in a series of 30 patients.

OBJECT: In the management of brainstem lesions, the place of stereotactic biopsy sampling remains debatable. The authors compared the results of magnetic resonance (MR) imaging, positron emission tomography (PET) scanning, and histological studies obtained in 30 patients who underwent MR imaging- and PET-guided stereotactic biopsy procedures for a brainstem mass lesion. METHODS: Between July 1991 and December 1998, 30 patients harboring brainstem mass lesions underwent a stereotactic procedure in which combined MR imaging and PET scanning guidance were used. Positron emission tomography scanning was performed using [18F]fluorodeoxyglucose in 16 patients, methionine in two patients, and both tracers in 12 patients. Definite diagnosis was established on histological examination of the biopsy samples. Interpretation of MR imaging findings only or PET findings only was in agreement with the histological diagnosis in 63% and 73% of cases, respectively. Magnetic resonance imaging and PET findings were concordant in 19 of the 30 cases; in those cases, imaging data correlated with histological findings in 79%. Treatment based on information derived from MR imaging was concordant with therapy based on histological findings in only 17 patients (57%). Combining MR imaging and PET scanning data, the concordance between the neuroimaging-based treatment and treatments based on histological findings increased to 19 patients (63%). In seven patients who underwent biopsy procedures with one PET-defined and one MR imaging-defined trajectory, at histological examination the PET-guided samples were more representative of the tumor's nature and grade than the MR imaging-guided samples in four cases (57%). In 18 patients PET scanning was used to define a biopsy target and provided a diagnostic yield in 100% of the cases. CONCLUSIONS: Although the use of combined PET and MR imaging improves radiological interpretation of a mass lesion in the brainstem, it does not accurately replace histological diagnosis that is provided by a stereotactically obtained biopsy sample. Combining information provided by MR imaging and PET scanning in stereotactic conditions improves the accuracy of targeting and the diagnostic yield of the biopsy sample; an MR imaging- and PET-guided stereotactic biopsy procedure is a safe and efficient modality for the management of mass lesions of the brainstem.

Adolescent↗
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

[Cerebellar hemorrhage complicating a supratentorial craniotomy. A case report and review of the literature].

Postoperative cerebellar hemorrhage after a supratentorial craniotomy represents a rare event. We report a case of a patient with a meningioma of the jugum who developed suddenly after surgery a neurological deterioration due to a cerebellar hemorrhage detected on the CT scan. An occipital craniectomy and an external ventricular drainage were performed in emergency. A complete neurological recovery was observed after surgery. Nineteen similar other cases are found in the literature. Pre- and postoperative high blood pressure, lowered intracranial pressure and mispositioning of the head during surgery could be at the origin of the hemorrhage. Size of the hemorrhage, time between diagnosis and treatment represent two prognostic factors. All patients, who present a neurological deterioration in postoperative course, must have CT scan including posterior fossa.

Cerebellar Diseases↗
PubMed1999

Prevention of epidural fibrosis in a prospective series of 100 primary lumbo-sacral discectomy patients: follow-up and assessment at re-operation.

An implantable device (ADCON-L), which acts as a resorbable barrier to epidural fibrosis following lumbar discectomy, has been shown to minimize the formation of peridural fibrotic scar and to improve the post-operative outcome, in two large controlled and multi-center clinical trials. In this prospective study, 100 patients were treated with the device during their first-time lumbo-sacral discectomy surgeries and monitored for 12 months. During this time interval, four of these patients required re-operation. In these cases, epidural scar and ease of dissection were systematically evaluated and recorded. At the time of re-operation, in all four patients, absent or minimal soft scar tissue was found where ADCON-L had been placed, no adhesions to the involved root were observed, and the dissection was easier than expected; the healing of the surgical wound was excellent , and no residual implant material was found. These observations indicate that the use of ADCON-L at the time of the first lumbar disc surgery minimizes the hazards and difficulty that can be encountered in a subsequent revision surgery due to the presence of epidural fibrosis, and may therefore improve the chances of satisfactory outcome following re-operation.

Adolescent↗
PubMed1999

Traumatic epidural hematoma of the cervical spine: magnetic resonance imaging diagnosis and spontaneous resolution: case report.

OBJECTIVE AND IMPORTANCE: Demonstration of interest of medical treatment of cervical epidural hematomas. CLINICAL PRESENTATION: A young patient developed cervical pain after experiencing cervical trauma. Computed tomography and magnetic resonance imaging demonstrated an epidural cervical hematoma. A spontaneous resolution of the clinical symptoms and the radiological abnormalities was observed. CONCLUSION: Although surgical decompression is generally regarded as mandatory in selected patients with incomplete and nonprogressing deficits, conservative management may be possible.

Adult↗
PubMed1999

Arnold Chiari Type I malformation presenting as a trigeminal neuralgia: case report.

OBJECTIVE AND IMPORTANCE: Arnold Chiari Type I malformation usually presents as headache, arm numbness, dysesthesia, upper weakness, or gait difficulty. We report a case of Chiari malformation presenting as a left trigeminal neuralgia. CLINICAL PRESENTATION: A patient with a history of 29 years of trigeminal neuralgia was admitted. He was treated with three thermocoagulations. Microvascular decompression was planified. Magnetic resonance imaging was performed, and it demonstrated an Arnold Chiari malformation. After surgery, the patient was asymptomatic. INTERVENTION: Posterior fossa decompression by enlarging the foramen magnum and aspiration of the cerebellar tonsils was performed. CONCLUSION: The trigeminal neuralgia could be attributable to a compression of the trigeminal nucleus. The compression of the nucleus could explain both the pain and the regression after surgery. This is the second reported case of pure trigeminal neuralgia in Arnold Chiari malformation.

Aged↗
PubMed1999

Supratentorial pilocytic astrocytomas, astrocytomas, anaplastic astrocytomas and glioblastomas are characterized by a differential expression of S100 proteins.

The levels of expression of the S100A1, S100A2, S100A3, S100A4, S100A5, S100A6 and S100B proteins were immunohistochemically assayed and quantitatively determined in a series of 95 astrocytic tumors including 26 World Health Organization (WHO) grade I (pilocytic astrocytomas), 23 WHO grade II (astrocytomas), 25 WHO grade III (anaplastic astrocytomas) and 21 WHO grade IV (glioblastomas) cases. The level of the immunohistochemical expression of the S100 proteins was quantitatively determined in the solid tumor tissue (tumor mass). In addition twenty blood vessel walls and their corresponding perivascular tumor astrocytes were also immunohistochemically assayed for 10 cases chosen at random from each of the four histopathological groups. The data showed modifications in the level of S100A3 protein expression; these modifications clearly identified the pilocytic astrocytomas from WHO grade II-IV astrocytic tumors as a distinct biological group. Modifications in the level of S100A6 protein expression enabled a clear distinction to be made between low (WHO grade I and II) and high (WHO grade III and IV) grade astrocytic tumors. Very significant modifications occurred in the level of S100A1 protein expression (and, to a lesser extent, in their of the S100A4 and S100B proteins) in relation to the increasing levels of malignancy. While the S100A5 protein was significantly expressed in all the astrocytic tumors (but without any significant modifications in the levels of malignancy), the S100A2 protein was never expressed in these tumors. These data thus indicate that several S100 proteins play major biological roles in human astrocytic tumors.

Adolescent↗