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Resume Introduction Nous avons compare quatre methodes d’evaluation des modifications de perfusion cerebrale chez 11 patients presentant une hydrocephalie a pression normale et beneficiant d’une tomoscintigraphie cerebrale au Bicisate (ECD, Neurolite®) marque au technetium 99 avant et apres injection d’acetazolamide. Materiel et methodes Ces 11 patients ont beneficie d’une tomoscintigraphie cerebrale avant et apres injection de 1 g d’acetazolamide. Nous avons utilise le 99mTc-Bicisate en split-dose avec une premiere injection de 370 MBq et une seconde de 1100 MBq. Apres reconstruction des volumes sous le logiciel MIRAGE®, nous avons realise une premiere analyse visuelle secondairement aidee de Neurogam® puis une analyse semi-quantitative manuelle par analyse des rapports ROI/REF et automatique avec les versions SPM99 et SPM2 du logiciel SPM. Resultats La methode d’analyse visuelle est immediate mais frequemment mise en defaut. L’apport du logiciel Neurogam® (Segami) semble une aide interessante a evaluer en fonction de l’experience du medecin-interprete. La methode semi-automatique manuelle est fastidieuse et ses resultats dependent du choix des regions d’interet et de reference necessaire a la normalisation d’activite. Enfin, la methode automatique realisee avec le logiciel SPM est fiable pour une analyse de population, mais son efficacite lors de l’analyse individuelle reste a evaluer.

In order to identify the cortical areas involved in the reading process and to spare them during surgery, we systematically studied cortical areas by direct cortical stimulation in patients operated on for brain tumours. Seventy-six cortical stimulation mapping studies for language were performed in 35 monolingual and 19 bi- or multilingual patients over a 5-year period. We systematically searched for reading interference areas in addition to standard naming areas using an 'awake surgery' technique for brain mapping. A 'reading aloud' task (translated into different languages in multilingual patients) was used. Brain mapping was performed in left (44 patients) and right (10 patients) hemispheres. Cortical areas involved in reading were identified according to the type of interference, location and distinctness from naming areas. Stimulation of several major hemispheric regions resulted in significant interference with reading aloud: (i) the lower part of the pre- and postcentral gyri (P < 0.00001); (ii) the dominant supramarginal, angular and the posterior part of the superior temporal gyri (P < 0.00001); (iii) in the dominant inferior and middle frontal gyri (P < 0.001); and (iv) in the posterior part of the dominant middle temporal gyrus (P < 0.05). Interferences in reading were generally found in small cortical areas, with intervening areas evoking no reading interferences. Only partial overlap between reading and naming sites was found. Reading-specific sites were preferentially found when stimulating dominant inferior parietal or posterior temporal areas. Different types of reading interferences were noted. While 'articulatory' interferences were found in pre- and postcentral gyri bilaterally, and ocular-induced movements in bilateral middle frontal gyri, paraphasias were found mainly in the dominant supramarginal and posterior superior temporal gyri. Reading arrest sites were found in many regions. Reading interference sites were also occasionally found in the non-dominant hemisphere. In bilingual patients, if common cortical areas could be found, language- and reading-specific areas were sometimes detected, lending support to the concept that bilinguals can have relatively distinct cortical representation of their language skills. Finally, in this series, the location of reading interference sites and their relative specialization showed considerable individual variability.

Cerebral cavernous malformations (CCM) are hamartomatous vascular malformations characterized by abnormally enlarged capillary cavities without intervening brain parenchyma. They cause seizures and focal neurological deficits due to cerebral hemorrhages. CCM loci have already been assigned to chromosomes 7q (CCM1), 7p (CCM2), and 3q (CCM3) and have been identified in 40%, 20%, and 40%, respectively, of families with CCM. Loss-of-function mutations have been identified in CCM1/KRIT1, the sole CCM gene identified to date. We report here the identification of MGC4607 as the CCM2 gene. We first reduced the size of the CCM2 interval from 22 cM to 7.5 cM by genetic linkage analysis. We then hypothesized that large deletions might be involved in the disorder, as already reported in other hamartomatous conditions, such as tuberous sclerosis or neurofibromatosis. We performed a high-density microsatellite genotyping of this 7.5-cM interval to search for putative null alleles in 30 unrelated families, and we identified, in 2 unrelated families, null alleles that were the result of deletions within a 350-kb interval flanked by markers D7S478 and D7S621. Additional microsatellite and single-nucleotide polymorphism genotyping showed that these two distinct deletions overlapped and that both of the two deleted the first exon of MGC4607, a known gene of unknown function. In both families, one of the two MGC4607 transcripts was not detected. We then identified eight additional point mutations within MGC4607 in eight of the remaining families. One of them led to the alteration of the initiation codon and five of them to a premature termination codon, including one nonsense, one frameshift, and three splice-site mutations. All these mutations cosegregated with the disease in the families and were not observed in 192 control chromosomes. MGC4607 is so far unrelated to any known gene family. Its implication in CCMs strongly suggests that it is a new player in vascular morphogenesis.

Background We prospectively evaluated the role of endoscopic third ventriculocisternostomy in the management of acute obstructive hydrocephalus created by cerebellar hematomas. Method Following a therapeutic diagram based on clinical and radiological signs, endoscopic third ventriculocisternostomy was used to treat hydrocephalus associated with cerebellar hematomas in 8 patients (male: 5, female: 3, mean age: 67 years-old). Causes of cerebellar hemorrhage were spontaneous in 6 cases, traumatic in 1 case, and acute bleeding of a posterior fossa tumor (lung metastasis) in the remaining case. Deeply comatose patients (Glasgow Coma Score between 3 and 5) and patients with signs of brainstem compression were initially excluded from this study. Findings Overall clinical improvement after third ventriculocisternostomy was achieved in all patients and was associated with the decrease of the ventricle size on follow-up CT scans. One patient who initially had a clot evacuation associated with an external ventricular drainage and persistant hydrocephalus had a successful third ventriculocisternostomy in the post operative course. No complication related to the procedure was noted. Interpretation In selected patients, third ventriculocisternostomy can be used to treat hydrocephalus associated with posterior fossa hematomas.

OBJECTIVE—To support the hypothesis about the potential compensatory role of ipsilateral corticofugal pathways when the contralateral pathways are impaired by brain tumours. METHODS—Retrospective analysis was carried out on the results of functional MRI (fMRI) of a selected group of five paretic patients with Rolandic brain tumours who exhibited an abnormally high ipsilateral/contralateral ratio of activation—that is, movements of the paretic hand activated predominately the ipsilateral cortex. Brain activation was achieved with a flexion extension of the fingers. Statistical parametric activation was obtained using a t test and a threshold of p

The purpose of this prospective, double-blind study was to correlate motor functional MRI (fMRI) with cortical brain mapping by intraoperative stimulation using 3D reconstructed images of the surface of the brain, and to validate the spatial data of fMRI in patients with brain tumors.Fourteen patients with tumors of the rolandic region underwent functional MR mapping of the hand region and subsequently cortical mapping before tumor resection. Data obtained with fMRI and brain mapping were not known previously by the neurosurgeon and by the neuroradiologist, respectively (double-blind study).In each case, the results of direct cortical mapping matched those obtained with fMRI, both positively and negatively, although the extent of the functional activations was larger than the area required to elicit the corresponding movement during intraoperative brain mapping.fMRI can be used before surgery to assess motor functional area in patients with rolandic tumors. More studies are needed to validate during surgery the real extent of fMRI activations.

The aim of the study was to evaluate the short term and long-term effects of long acting repeatable bromocriptine (= Parlodel-LAR*) in patients with macroprolactinomas. Twenty-nine patients (15 men and 14 women) aged 42 +/- 2.7 (M +/- SEM) years were injected with Parlodel-LAR* every 4 weeks during 3.3 +/- 0.3 years. The starting dose was 50 mg/injection, then it was increased to 100 mg in 11 patients and 150 mg in 9 patients. PRL levels decreased in all but one patient 4 weeks after the first injection (270 +/- 59 vs 934 +/- 210 ng/ml, p0.001), then became less than 20 ng/ml in 20/29 (69%) patients and finally became undetectable or low in 13/29 (45%) patients. Visual field defects were present in 12/29 patients before treatment. In 11/12 patients, treatment with Parlodel-LAR* resulted in an improvement and complete correction of visual field defects was observed in 8/12 patients. Adenoma size (2.5 +/- 0.2 cm before treatment) was reduced by at least 20% in 24/29 (83%) patients. Disappearance of adenoma was observed on CT scan in 8/29 (28%) patients after 28.7 +/- 5.3 months of treatment. Minor side effects occurred in 20 patients after the first injection then disappeared in 18 patients within the following 6 months of treatment. One patient had rhinorrhea after 3 months of treatment. Treatment with Parlodel-LAR* results in beneficial short-term effects (with rapid correction of recent onset visual field defects) and long-term effects (which can include complete disappearance of adenoma on CT scan evaluation) in patients with macroprolactinomas.

Objective To assess the feasibility of synthesis of O -(2-[ 18 F]-fluoroethyl)-L-tyrosine (FET), a new positron emission tomographic (PET) tracer described in several studies but not yet considered standard in management of glioma, in routine practice and to determine FET uptake in a homogeneous group of patients with suspected high-grade glioma. Design Prospective nonrandomized trial. Patients Twelve patients with suspicion of high-grade glioma. Results The mean (SD) FET uptake ratio was 3.15 (0.72) for the 12 patients and 3.16 (0.75) for the 11 patients with glioblastoma. Conclusion The initial results are promising and indicate that FET PET is a valuable and applicable tool for the imaging of high-grade glioma.

Object. In an attempt to gain a better understanding of the cerebral functions represented in the angular gyrus and to spare them during surgery, the authors studied patients with brain tumors located close to the angular gyrus and mapped cortical sites by using electrostimulation. Methods. Before undergoing tumor removal, six right-handed patients (five with left and one with right hemisphere tumors) were studied using cortical mapping with the aid of calculating, writing, finger-recognition, and color-naming tasks in addition to standard reading and object-naming tasks (for a total of 36 brain mapping studies). Strict conditions of functional site validation were applied to include only those cortical sites that produced repetitive interferences in the function tested. Preoperatively, four of the patients exhibited discrete symptoms related to Gerstmann syndrome while performing very specific tasks, whereas the other two patients presented with no symptoms of the syndrome. No patient had significant language or apraxic deficits. Distinct or shared cortical sites producing interferences in calculating, finger recognition, and writing were repeatedly found in the angular gyrus. Object- or color-naming sites and reading-interference sites were also found in or close to the angular gyrus; although frequently demonstrated, these latter results were variable and unpredictable in the group of patients studied. Finger agnosia and acalculia sites were also found elsewhere, such as in the supramarginal gyrus or close to the intraparietal sulcus. Mechanisms involved in acalculia, agraphia, or finger agnosia (either complete interferences or hesitations) during stimulation were various, from an aphasia-like form (for instance, the patient did not understand the numbers or words given for calculating or writing tasks) to an apparently pure interference in the function tested (patients understood the numbers, but were unable to perform a simple addition). Conclusions. Symptoms of Gerstmann syndrome can be found during direct brain mapping in the angular gyrus region. In this series of patients, sites producing interferences in writing, calculating, and finger recognition were demonstrated in the angular gyrus, which may or may not have been associated with object-naming, color-naming, or reading sites.

Object. In an attempt to gain a better understanding of how multiple languages are represented in the human brain, the authors studied bilingual patients who underwent surgery for brain tumors, during which the authors mapped cortical language sites by using electrostimulation. Methods. Reading, counting, and word retrieval tasks were studied in 12 right-handed bilingual patients with no language deficit. All bilingual patients were native to France. One patient spoke four languages. The patients constituted a nonhomogeneous group in terms of language proficiency or age of acquisition. Languages were evaluated and classified into three major groups, depending on proficiency and date of acquisition. Strict conditions of language site validation were applied, separating typical anomia sites from speech arrest or other language sites (such as hesitation sites). A total of 30 speech arrest sites, 16 anomia sites, and three sites of language difficulties (not typically classified as speech arrest) were found throughout the 26 language studies performed. Strict overlapping of language areas (for all language tasks) was found in five patients, whereas the remaining seven had at least one area that was language-specific and sometimes task-specific. Specific areas for a particular language were found for word retrieval tasks (anomia) in eight sites (50%) but also in six (20%) of the reading or counting sites (speech arrest), either in frontal (three patients) or in temporoparietal (four patients) regions. Among the four early bilingual patients tested (languages acquired before the age of 7 years), three had language-specific cortical areas. Interestingly, six patients in this series who had a discrepancy between two languages did not have more cortical areas devoted to the less proficient language (with acknowledgment of the limit in cortical exposure available for testing by the craniotomy). Conclusions. In this series, the authors found that bilingual patients could have common but also different cortical areas for both languages in temporoparietal areas and in frontal areas. In some cases, the authors found that language tasks such as counting, reading, or word retrieval in different languages can be sustained by language- and task-specific cortical areas. In bilingual patients, cortical mapping should ideally be performed using different language tasks in all languages in which the patient is fluent.

We prospectively evaluated the role of endoscopic third ventriculocisternostomy in the management of acute obstructive hydrocephalus created by cerebellar hematomas.Following a therapeutic diagram based on clinical and radiological signs, endoscopic third ventriculocisternostomy was used to treat hydrocephalus associated with cerebellar hematomas in 8 patients (male: 5, female: 3, mean age: 67 years-old). Causes of cerebellar hemorrhage were spontaneous in 6 cases, traumatic in 1 case, and acute bleeding of a posterior fossa tumor (lung metastasis) in the remaining case. Deeply comatose patients (Glasgow Coma Score between 3 and 5) and patients with signs of brainstem compression were initially excluded from this study.Overall clinical improvement after third ventriculocisternostomy was achieved in all patients and was associated with the decrease of the ventricle size on follow-up CT scans. One patient who initially had a clot evacuation associated with an external ventricular drainage and persistant hydrocephalus had a successful third ventriculocisternostomy in the post operative course. No complication related to the procedure was noted.In selected patients, third ventriculocisternostomy can be used to treat hydrocephalus associated with posterior fossa hematomas.

OBJECTIVE The aim of this article was to analyze the technical and methodological issues resulting from the use of functional magnetic resonance image (fMRI) data in a frameless stereotactic device for brain tumor or pain surgery (chronic motor cortex stimulation). METHODS A total of 32 candidates, 26 for brain tumor surgery and six chronic motor cortex stimulation, were studied by fMRI scanning (61 procedures) and intraoperative cortical brain mapping under general anesthesia. The fMRI data obtained were analyzed with the Statistical Parametric Mapping 99 software, with an initial analysis threshold corresponding to P < 0.001. Subsequently, the fMRI data were registered in a frameless stereotactic neuronavigational device and correlated to brain mapping. RESULTS Correspondence between fMRI-activated areas and cortical mapping in primary motor areas was good in 28 patients (87%), although fMRI-activated areas were highly dependent on the choice of paradigms and analysis thresholds. Primary sensory- and secondary motor-activated areas were not correlated to cortical brain mapping. Functional mislocalization as a result of insufficient correction of the echo-planar distortion was identified in four patients (13%). Analysis thresholds (from P < 0.0001 to P < 10−12) more restrictive than the initial threshold (P < 0.001) had to be used in 25 of the 28 patients studied, so that fMRI motor data could be matched to cortical mapping spatial data. These analysis thresholds were not predictable preoperatively. Maximal tumor resection was accomplished in all patients with brain tumors. Chronic motor cortex electrode placement was successful in each patient (significant pain relief >50% on the visual analog pain scale). CONCLUSION In brain tumor surgery, fMRI data are helpful in surgical planning and guiding intraoperative brain mapping. The registration of fMRI data in anatomic slices or in the frameless stereotactic neuronavigational device, however, remained a potential source of functional mislocalization. Electrode placement for chronic motor cortex stimulation is a good indication to use fMRI data registered in a neuronavigational system and could replace somatosensory evoked potentials in detection of the central sulcus.

The indications for surgery of slow growing tumours like low grade astrocytomas in eloquent areas are difficult. The timing and the benefit/risk ratio of the surgery must be evaluated, taking into account the potential post operative deficit. The purpose of this study was: a) to validate the data obtained with functional MRI (FMRI) by direct cortical stimulation in patients who are candidate for surgery; b) to demonstrate the usefulness of FMRI coupled with cortical brain mapping and 3D reconstructions of the surfaces of the brain in low grade astrocytoma. FMRI of the hand-motor cortex was performed in 8 patients with low grade astrocytomas. They subsenquently underwent direct cortical mapping to correlate the results of FMRI and resective surgery sparing the functional area. In the 8 cases, the results of direct cortical mapping in the precentral region matched accurately those obtained from FMRI. When surgical resection of low grade astrocytoma in the motor areas is considered, FMRI used with intra-operative cortical mapping can help the surgeon to spare functional areas during tumour removal.

This study, conducted by a group of neurosurgeons who devote a large portion of their professional time to the treatment of degenerative lumbar spine lesions, was prompted by the dramatic increase in the number of lumbar spinal fusion procedures performed over the last few years in a broad spectrum of disorders ranging from chronic incapacitating low back pain to lumbar spinal stenosis. In the authors' experience, lumbar spinal fusion is rarely warranted and often of dubious efficacy. To investigate this contradiction, the authors reviewed the medical literature on lumbar spinal fusion for the treatment of degenerative spinal stenosis. They have defined lumbar instability as objectively as possible, reviewed clinical and roentgenographic features, described spinal fusion techniques with the drawbacks of each, and evaluated outcomes of surgery for degenerative lumbar spinal stenosis with or without fusion. Findings demonstrate that spinal fusion is a technique of unproven benefit that should be used only in carefully selected patients until results of reliable, prospective, comparative clinical trials become available. In the authors' opinion lumbar spinal fusion should be used as the first-line treatment only in young patients with clinical manifestations directly related to lumbar instability as defined in this study, when decompression requires removal of both facet joints and of the disk (which is rarely the case) or when simple decompression is followed by a recurrence of symptoms ascribable to worsening vertebral slippage.

A non randomized pilot study has been undertaken to evaluate the feasibility of local immunotherapy (IT) of recurrent glioblastoma multiforme (GM) by continuous intracerebral perfusion of recombinant interleukin-2 (rIL-2, Eurocetus) with and without lymphokine activated killer (LAK) cells. At time of surgical removal of the tumor, a catheter was implanted in the cavity left by tumor debulking allowing continuous perfusion of rIL-2. Five patients received 18 x 10(6) IU/day or rIL-2 for five days. At days 1, 3, and 5 after surgery, rIL-2 perfusion was briefly interrupted for the injection of LAK cells. Eight other patients received rIL-2 alone, either 24 x 10(6) IU/day (five patients) or 54 x 10(6) IU/day (three patients). Capillary leak syndrome, which is the main side effect of systemic infusion of rIL-2, was never observed, but local immunotherapy induced fever, confusion, and cerebral edema in all patients. Despite local IT, tumor progression was diagnosed by CT scan 4 to 12 weeks after the treatment.

Arteriovenous malformations (AVMs) and benign or low grade, small malignant tumors can be treated by stereotactic radiotherapy in a single fraction. This report describes a technique for stereotactic treatment of small lesions using conventional, fractionated, photon beam irradiation. The Laitinen's stereoadapter, non-invasive head frame was used. This device was tested for accuracy by serial mountings and found to be accurate within 1 mm. The accuracy of the dose delivered was within 2%. Adaptation of this device to the linear accelerator required the design of secondary circular collimators which decreased the penumbra from 3-4 mm to 2-3 mm. The dose fall off outside the target volume is steep enough when using two non-coplanar arcs (90 to 10% within 1 cm). Thermoluminescent dosimetry (TLD) in a humanoid phantom showed good correlation with the calculated dose. This system permits delivery of fractionated radiation therapy to small volumes, easily and accurately, under stereotactic conditions.

Brain abscesses are associated with high mortality and morbidity even in the antibiotic era and with complex imaging techniques, mainly because of delayed diagnosis. Several reasons can be identified: (1) the incidence of abscesses is low, about 1.1/100 000 person-year1; (2) clinical features may be non-specific without evidence of infection and with neurological signs similar to tumours, which are 50 times more frequent; (3) neuroradiological imaging may be confusing specially in the early stages. The only way to improve the outcome of this pathology is to consider an abscess when faced with a space occupying lesion and to perform a stereotactic biopsy even in elderly or severely deteriorated patients. Recently, in vivo 1H MR spectroscopy (MRS) was reported to give metabolic information on brain abscesses very different from that of brain tumours, permitting a non-invasive differential diagnosis between these two diseases.2 (A) T2 weighted MRI in the axial plane. (B) In vivo1H MRS spectrum from abscess (echo time=135 ms). (C) In vitro 400 MHz 1H MRS spectrum from aspirated pus (aa = aminoacids Ac=acetate, Ala=alanine, Gly=glycine, Lac=lactate, Succ=succinate, Tau=taurine). We report a case in which the diagnosis of an abscess was made on the basis of in vivo 1H MRS resulting in complete …

Introduction L’encephalite limbique paraneoplasique est caracterisee par des troubles mnesiques et de la personnalite le plus souvent associes a un cancer pulmonaire a petites cellules. Nous rapportons un cas associe a un cancer du rein. Observation Une patiente de 60 ans a ete hospitalisee pour prise en charge de troubles mnesiques et phasiques associes a des troubles du comportement et de l’humeur d’apparition subaigue. Le scanner et l’IRM cerebrale retrouvaient des anomalies en rapport avec une sequelle d’un meningiome bilateral dont la composante droite avait ete operee en 2004 et la gauche irradiee en 2005. L’EEG retrouvait des pointes temporales gauches. L’analyse du LCR ne mettait pas en evidence d’hyperproteinorachie mais la presence d’un profil oligoclonal. Le bilan etiologique ne retrouvait pas d’argument pour une origine infectieuse, inflammatoire ou degenerative. Le scanner thoraco-abdomino-pelvien retrouvait une masse hyperdense du pole inferieur du rein gauche. Dans l’attente de l’exerese, une corticotherapie intra veineuse a ete mise en place avec efficacite. La nephrectomie gauche a confirme le diagnostic d’adenocarcinome a cellules claires bilateral. Dix jours apres l’intervention on constatait une amelioration de la symptomatologie clinique confirmee par les evaluations neuropsychologiques, une disparition des anomalies EEG et du profil oligoclonal. La patiente a beneficie d’un traitement par Endobuline® dans l’attente du traitement par radiotherapie du cancer du rein droit. Discussion II s’agit du 7e cas d’encephalite limbique associe a un cancer du rein decrit dans la litterature. Ce cas est typique dans sa presentation clinique bien que les troubles de la vigilance ne soient pas classiques. L’EEG et l’analyse du LCR sont contributifs, les anticorps antineuronaux sont negatifs comme dans les cas rapportes precedemment. La physiopathologie n’est pas connue. Conclusion Nous rapportons un cas d’encephalite limbique associe a un cancer du rein ayant regresse apres traitement de la tumeur associe a un traitement immunomodulateur complementaire.

Seventy-four measurements of cerebral blood flow (CBF) were performed using the Xenon 133 inhalation method in 50 cases of spontaneous subarachnoid hemorrhage. This method is non-traumatic, reproducible and dependable. A correlation was found between clinical condition and CBF values, but in a number of cases which cannot be dismissed, very low mean CBF values or ischemic foci were revealed where clinical state gave no indication of same. A poor correlation appeared between vasospasm seen by angiography and ischemic foci detected by isotopic technique. Patients' age influenced CBF values but not clinical evolution. CBF values, measured in the first two weeks of illness, were significantly higher in those patients having favorable outcome, whatever their clinical state at the time of CBF measurement (comas excluded). The figure of 60 ml/100g/min. for mean cortical flow seemed to be a critical level below which risk of complications was greater. Conversely, in every case where mean cortical flow measured above 70 ml, outcome was favorable. Thus, CBF measurement promises to be a valuable prognostic tool, playing an important role in the therapeutic strategy for this type of patient.

Following a recent statistical survey of 56 cases over a period of 3 years the authors considered the choice between the frontal or the parieto-temporal approaches to intracerebral haematomas. From their anatomical studies they considered that the frontal route is the better for approach to haematomas of the external capsule, whereas the parieto-temporal approach is preferred for haematomas of the internal capsule.

The development of atraumatic measurement of CBF by inhalation or intravenous injection of xenon 133 and the recent perfection of dependable and easy to handle apparatus have stimulated renewed interest in this problem and have resulted in new publications in the last few years [1, 2, 5, 6, 10].

The authors sought to compare 1H magnetic resonance spectroscopy (MRS) spectra from extracts of low-grade and high-grade gliomas, especially with respect to the signals of choline-containing compounds.Perchloric acid extracts of six high-grade and six low-grade gliomas were analyzed by 1H MRS at 9.4 Tesla.The signals of glycerophosphocholine (GPC) at 3.23 ppm, phosphocholine (PC) at 3.22 ppm, and choline (Cho) at 3.21 ppm were identified in both types of tumors. The absolute concentrations of all Cho-containing compounds (GPC + PC + Cho) in high-grade and low-grade gliomas were significantly different. The relative contributions of each of the Cho-containing compounds to the total choline signal were also statistically different. For high-grade gliomas, the choline signal is composed of GPC, PC, and Cho in a well-balanced contribution, whereas in low-grade gliomas, the signal is largely due to GPC with a small involvement of PC and Cho.The differences in the concentration and the repartition of Cho-containing compounds seem to be a marker of high-grade gliomas. They could also help to discriminate between high- and low-grade gliomas in some difficult cases, especially if there is histologic uncertainty between anaplastic astrocytomas and low-grade oligodendrogliomas.

To evaluate the capabilities and the limitations of motor functional magnetic resonance imaging (fMRI) in the presurgical evaluation of the cerebral tumors located in or near the motor homunculus. To correlate each type of activation with the histologic characteristics of each tumor.fMRI was performed in 17 patients (14 adults and 3 children), without any motor deficit, presenting with various intracerebral tumors. Three fMRI activation paradigms were used: contralateral to the lesion: ballistic opposition of the fingers, flexion-extension of the foot and click of the tongue. Four patients, without motor deficit, with cerebral tumors far from the motor homunculus were used as control group to look for nonspecific activations. In all cases, the histopathology of the tumor was known accurately.In 11 patients with infiltrating tumors, the activated areas were clearly displaced. They were often intratumoral and scattered in correlation with the degree of infiltration. Two patients with noninfiltrating tumors (meningioma) showed extratumoral shift of the activated areas. Four patients presenting cerebral tumors far from the homunculus motor did not show intratumoral activation. The supplementary motor area and the ipsilateral primary motor cortex were also reproducibly activated during the motor tasks. The task of the tongue was often artifacted, probably because of the head motion.These preliminary results suggest that the histopathologic characteristics of a tumor, and especially its microscopic structure, play a role in the organization of the motor functional area. In a small number of cases, fMRI could be used intraoperatively with a neuronavigation system.

The therapeutic efficacy of intravenous nimodipine to treat the syndrome of delayed ischemic deterioration or vasospasm after subarachnoid hemorrhage caused by a ruptured aneurysm was investigated in a randomized, double-blind, placebo-controlled multicenter study. A total of 188 patients (nimodipine (N) = 102, placebo (P) = 86) were enrolled in the study, both pre- and postoperatively, within 24 hours of clinical deterioration connected with vasospasm or within 24 hours of arteriography that identified vasospasm. After 61 patients were excluded for not meeting study criteria or for protocol violation, the results were supported by 127 validated case reports: 73 patients received intravenous treatment with nimodipine, and 54 were given placebo. Analysis of the main criterion of efficacy, the number of deaths and of patients with severe deficit related to vasospasm alone, showed a significant statistical difference (N = 8 (19%), P = 17 (49%), P = 0.01). The risk of death or disability was reduced by 66% in the treated group. Analysis of this criterion by type of inclusion (clinical or angiographic) also showed a significant reduction in the clinical group (P = 0,05), but there was no difference in the angiographic group. The risk of mortality connected with vasospasm was reduced by 82%, but analysis by group showed that there was no significant difference for those patients included on clinical criteria, whereas mortality was reduced to a much greater extent in the angiographic group. These results demonstrate the therapeutic efficacy of nimodipine in reducing secondary ischemic brain damage in patients already suffering from angiographic vasospasm or delayed ischemic deterioration.