Ethics and meningiomas: From prudence to obstinacy? The position of the neurosurgeon (for treatment or insurance purposes) in the case of complaints concerning post-operative clinical deterioration.

To treat or not to treat an asymptomatic or pauci-symptomatic benign meningioma, that is the question. And if treatment is necessary, what is the best technique: radical resection, sub-total resection or radiotherapy? This question is also pertinent for meningiomas of the skull base, posterior part of the sagittal sinus, anterior part of the foramen magnum and cerebellopontine angle. When the results of the treatment are good, the patient and the surgeon are satisfied. But when a new neurological deficit appears after the treatment, the patient is entitled to obtain compensation. What should be the position of the specialist medical assessor in this situation when the prognosis of these benign tumors is unknown? Is the preoperative information that is due to the patient complete, objective and sufficient? Is the therapeutic indication unquestionable? Is the technique irreproachable? For meningiomas, there is no "evidence-based medicine"; the therapeutic option is often based on the personal experience and/or the education of the surgeon and thus is, in fact, highly subjective.

[The origins of the French neurosurgery]. / Aux origines de la neurochirurgie française.

Modern French neurosurgery starts at the beginning of the XXth century under the motivation of Joseph Babinski. He submitted his patients to Thierry de Martel who had learned this new specialized area of medicine with H. Cushing in the États-Unis and V. Horsey in Great Britain. His first successfully treated case of an intracranial tumor was published in 1909. But the true founding father was Clovis Vincent, initially a neurologist and collaborator of de Martel, who became the first chairman in 1933 of the neurosurgical department at the Pitié hospital of Paris and the first professor of neurosurgery in 1938. After the Second World War, many departments were created outside of Paris. Neurosurgery was definitively recognized as a specialized area in medicine in 1948. Currently, more than 400 neurosurgeons work in France. Because I had the very great privilege to be present at the birth of this society in 1970 and to still be in contact with some of the second and third generation of French neurosurgeons who led it to its high international recognition, the Chairman of the French Neurosurgical Society asked me to write this short historical vignette.

[Evaluation of the clinical and radiological results of cervical longitudinal median somatotomy without graft]. / Evaluation des résultats cliniques et morphologiques de la somatotomie cervicale médiane longitudinale sans greffe.

OBJECTIVES: To evaluate the clinical and radiological results of cervical longitudinal median somatotomy without graft, used for the treatment of cervical myelopathy and radiculopathy, and compare it to techniques with graft and to laminectomies. MATERIAL AND METHOD: Thirty-four patients (25 males and nine females), with a mean age over 60 years, were included in a study comparing pre- and postoperative clinical status on the Japanese Orthopaedic Association (JOA) functional scale and radiological status with evaluation of the cervical curve on plain films and dynamic tests in flexion and extension. RESULTS: No significant difference was found with the clinical and anatomical results published in the literature concerning median somatotomies performed with graft and/or osteosynthesis and laminectomies and their variants. CONCLUSIONS: The cervical longitudinal median somatotomy without graft is an easy and reliable technique that can be proposed as first-line treatment for cervical spondylotic myelopathy related to anterior compression. It decreases the cost and the duration of the surgical procedure, it protects the patient from the complications and sequelae related to graft harvesting and the use of implants. It should be limited to patients without preoperative kyphosis who are over 50 years old.

Propionibacterium acnes contamination in lumbar disc surgery.

Previous studies have shown that Propionibacterium acnes may be responsible for low-grade infection of the intervertebral discs of patients with severe sciatica. The aim of this study was to prospectively investigate the presence of bacteria in disc fragment samples obtained during surgery for lumbar disc herniation. P. acnes was cultured from disc fragments in two (3.7%) of 54 patients studied. In addition, control cultures taken from ligamentum flavum and muscle from these two patients were also positive for P. acnes. Similar control cultures were positive for P. acnes from a further ten (18.5%) patients. Four air samples taken during surgery all contained P. acnes; the organism was also found from three of 54 laminar flow control cultures. Sample contamination appears the most likely cause for the presence of P. acnes in the lumbar disc fragment cultures.

[Histopathology of central nervous system cavernomas]. / Anatomie pathologique des cavernomes du système nerveux central.

Central nervous system cavernomas are vascular malformations, which occur in two circumstances: sporadic forms and familial autosomal dominant forms. The lesion consists of enlarged, closely packed vessels without interposition of brain parenchyma, surrounded by hemosiderin and gliosis, calcified in few cases. In 80% of sporadic forms the lesion is unique, multiple lesions are rare (median: 4). In familial forms the lesions are always multiple. Cavernomas are often associated with other vascular malformations, especially with venous developmental anomalies. The size of cavernomas is variable from 1 mm to several centimeters. About 70% of cases are supratentorial and 30% in the posterior fossa, particularly in the brain stem. Macroscopic and histopathological findings are typical and the diagnostic is generally easy.

[Results of surgical treatment]. / Résultats du traitement chirurgical.

In this chapter we report the results of the main papers of the international literature, but it is difficult to make an objective synopsis because only the best results are published and failure and complications remain confidential. Few papers describe "general complications" as thrombo phlebitis, wound infection, cardio respiratory insufficiency... which are probably as frequent as for all intracranial or spinal surgical procedures. The postoperative neurological status depends essentially on the location of the lesion. In non eloquent area, the postoperative neurological status is almost always excellent. But in a hemispheric functional area, basal ganglia and brain stem it is frequent to observe neurological sequellae; in the better series of the literature, 80% of the patients achieve a good outcome equivalent to or better than before the operation, but 20% are worsened. It is important to remember this fact before discussing the surgical indication. The risk of hemorrhage disappears after total surgical resection; and it is one of the benefits of the treatment, but this objective can be reached only when the lesion is unique. The risk persists in multiple forms and "de novo" cavernomas are always possible especially in familial forms. The main benefit is the treatment of epilepsy for seizure control. In case of good concordance between the location of the cavernoma and the clinical and electrical data, lesionectomy alone or lesionectomy with resection of the perilesional hemosiderin ring provide good results. In the event of severe epilepsy without good concordance between the site of the cavernoma and symptoms, the surgical approach may be functional and outcome less satisfactory.

[Natural history of cavernomas of the central nervous system]. / Histoire naturelle des cavernomes du système nerveux central.

We present a critical review of the literature on the central nervous system cavernomas in order to highlight their natural history and to define the most appropriate management of these rare lesions. The prevalence is now estimated from 0.3 to 0.7% in the general population without any significant difference by gender; 25% of cases are pediatric. Two forms of the disease can be described: sporadic forms in 80% of cases, characterized by isolated or rare lesions and familial dominant autosomic forms characterized by multiple and evolutive lesions. The incidence is not well known, the consultation of the French PMSI database suggests that 50 to 100 cases are operated on each year (1 to 2 per million). Cavernomas are dynamic lesions: growing in many cases, seldom remaining quiescent and disappearing in rare cases. The anatomical evolution is more pejorative in familial forms. "De novo" cases are now well known, either in familial or sporadic forms and after radiotherapy. Many lesions are totally asymptomatic, but the frequency of symptomatic forms is debated in the literature from 3 to 90%... The hemorrhagic risk is evaluated from 0,5 to 3% each year, depending on the localization, and the risk of rebleeding is more important but not well known. The epileptic risk is correlated to the localization, more frequent for temporal and frontal lesions from 4,5 to 11% each year, but these data are controversial. The natural history depends on the topography: hemispheric, deep-seated, brain stem, cerebellum or intramedullary and in pediatric situations. Each situation will be treated in this report.

[Microcystic meningiomas: comparison of histology and computed tomography]. / Aspects histologiques et tomodensitométriques des méningiomes microkystiques.

INTRODUCTION: Microcystic meningiomas are defined by large vacuolated and stellate shaped cells. We recently examined a microcystic meningioma mimicking a malignant tumor on computed tomography (CT). The aim of the current study was to compare the radiological features of microcystic meningiomas with their histological patterns. METHODS: We have diagnosed 7 intracranial microcystic meningiomas among 204 meningiomas registered in the files of our Department of Pathology from 1994 to 2001. All CT scans performed before surgery were reviewed. RESULTS: Three of the microcystic meningiomas appeared as entirely microcystic tumors. Two of them were homogeneously hypodense or isodense on CT scan. The third mening was heterogeneous, containing some blood. The histologic pattern of the 4 other meningiomas showed microcystic tumor cells associated with meningothelial or fibrous tumor cells. These meningiomas were heterogeneous on CT scan. All meningiomas seemed to be connected to the dura mater. Three tumors were strongly and homogeneously enhanced after contrast media injection while 3 others were heterogeneously enhanced. No enhanced CT scan was available for 1 case. Astrocytomas were incorrectly diagnosed by CT scan in the 3 heterogeneously enhanced tumors. Meningiomas were correctly diagnosed in the 3 strongly enhanced tumors. CONCLUSION: The presence of microcystic tumour cells in meningiomas often results in erroneous diagnosis on CT scan, particularly for those which are heterogeneously enhanced. In these cases, a diagnosis of astrocytoma is often made.

[Non traumatic spinal epidural hematomas. Report of twenty cases. Review of the literature and outcome aspects]. / Hématomes épiduraux non traumatiques du rachis. Présentation de 20 cas. Revue de la littérature et étude des aspects évolutifs.

BACKGROUND AND PURPOSE: We report a personal series of 20 non traumatic spinal epidural hematomas and study outcome aspects with a review of data in the literature. METHOD: Clinical presentation of non-traumatic spinal epidural hematomas observed between January 1980 and December 1998 was acute in 17 cases (85%) and chronic in 3 (15%). Symptoms were spinal and/or radicular pain, sensorimotor and sphincter dysfunction. Radiological evaluation consisted in myelography (n=6), myelography-CT scan (n=5), CT scan (n=1) and MRI (n=9). Patients underwent surgery in 15 cases, between 8 hours and 2 months after the first symptoms. All our patients were clinically reevaluated between 2 and 4 months after either surgery or admission for cases of spontaneous resolution. RESULTS: Good results (complete neurological resolution or moderate sequelae) were observed in 14 patients (70%). A partial recovery with major persistent neurological impairment was observed in 1 patient (5%), an initial persistent neurological impairment in 1 (5%). Three patients (15%) died and 1 (5%) was lost to follow-up. Complete spontaneous resolution were observed in four patients. CONCLUSION: Postsurgical outcome is mainly related to the preoperative neurological impairment, the duration of spinal cord compression and the time interval between the onset of symptoms and maximal deficit. A prompt laminectomy is necessary except in the cases where a spontaneous resolution can be expected from the early neurological course.

[A patient with white matter involvement and superficial hemosiderosis of the central nervous system]. / Atteinte de la substance blanche et hémosidérose marginale du névraxe.

We present a patient with a superficial siderosis and a white matter involvement on MRI and a demyelinating pattern on visual evoked potentials. White matter involvement is supposed to be secondary to vascular modifications induced by superficial siderosis.

[Multidisciplinary treatment of neurologic pain and indications for antalgic surgery]. / Prise en charge de la douleur neurologique en équipe pluridisciplinaire et décision de chirurgie antalgique.

We present our multidisciplinary approach systematically adopted for patients with resistant pain. All the anatomic, pathophysiological, clinical, radiographical, electrophysiological and psychological aspects of pain should be considered before deciding on treatment indication. These principles are illustrated by a description of different available medical and surgical techniques for the treatment of paraplegic pain. We emphasize the importance of pain centers in caring for these patients. All possibilities for antalgic treatment can be considered in such centers, providing a better approach to all aspects of pain.

[Chondrosarcoma of the infratemporal fossa with intracranial extension. Case report and review of the literature]. / Chondrosarcome de la fosse infra-temporale avec extension intra-crânienne. Revue de la littérature et discussion à propos d'un cas.

Chondrosarcomas are rarely observed in the infratemporal fossa. We report a rare case with temporal extension into the middle cerebral fossa without meningoencephalic invasion. Surgical excision was followed by radiotherapy. The patient died 7 years later from another cause free of tumoral recurrence. We discuss the current understanding of cephalic chondrosarcomas involving the infratemporal fossa.

[Anterior and antero-lateral surgery for degenerative cervical spine diseases. Role of graft and osteosynthesis. Analysis of practices of the French-speaking european neurosurgeons]. / Chirurgie antérieure et antéro-latérale du rachis cervical dégénératif. Place de la greffe et de l'ostéosynthèse. Analyse de la pratique des neurochirurgians européens francophones.

The neurological complications of cervical spondylosis depend on the direct or indirect effects of the mechanical compression of the spinal cord and roots. Nobody questions the interest of a surgical decompression, when the medical treatment is ineffective, but there is no consensus on the choice of the surgical approach and on the necessity of performing a graft with or without osteosynthesis after an anterior decompression. On the initiative of the French Speaking Neurosurgical Society (SNLF), we have analyzed the practices of its European members in 1998 and report here the results of this study which collects 3 645 surgical procedures for degenerative pathology of the lower cervical spine responsible for radiculopathy or myelopathy. An anterolateral approach was used in 85.3 % of all cases, among which 87.9 % of extensive discectomy (Smith Robinson or Cloward technique) and 12.1 % of median somatotomy. In case of discectomy, no grafting was performed in 34.7 % of cases, grafting without fixation in 25.7 %, grafting with plating in 14.9 %, interbody cages in 21.9 %, other techniques in 2.8 %. In case of somatotomy, no grafting was performed in 17.8 % of cases, grafting without fixation in 15.5 %, and grafting with plating in all other cases. When a graft was performed, an autograft was used in 59.5 % of cases, hydroxyapatite in 24.4 %, and many other bone substitutes in rare cases every time. For the fixation, monocortical screwing was used in 75 % of all cases, and bicortical in 25 %. The reasons for these practices are equivocal and not based on scientific attitude. The reasons given are : to avoid discal plucking, to prevent or treat kyphosis and postoperative spinal instability, to prevent cervical postoperative pain, to help eliminate osteophytes and hypertrophy of the ligamentum flavum.

Development of an intracerebral glioma model in whole body irradiated hairless rats.

AIMS: To study the in vivo radiosensitivity of malignant gliomas, an animal glioma model was developed using the implantation of glioma cell lines into the brain of the Hairless rat (a mutant from the Sprague-Dawley strain, characterised by its complete absence of hair). METHODS: 10(6) malignant cells were suspended in 10 microliters phosphate buffered saline (PBS) and injected at a 4 microns depth into the left frontal lobe of an anaesthetised animal through a small craniotomy hole without opening the dura mater. The glioma cell line C6 (obtained from a chemically-induced rat glioblastoma) was introduced into 11 animals, and the human glioblastoma line G5 into 12 animals. RESULTS: The tumour take was checked using histological criteria. It was poor: 0% for the G5 line and only 27.3% for the C6 line. To improve the tumour growth rate, rats were subjected to a single dose (3.5 Gray) total body irradiation, 24 hours prior to injection, causing a marked immunosuppression. 84.6% of the rats grafted with the C6 line then produced tumours. Similar results (75% tumour take) were obtained using a stereotactic inoculation of the tumour cells. CONCLUSIONS: Thanks to the contribution of whole body irradiation, an animal intracerebral glioma model was establish, which can be used for clinical and biological studies.

Expression of beta2 integrins and macrophage-associated antigens in meningeal tumours.

This study assessed the expression of leukocyte integrins and macrophage-associated antigens in meningiomas. Fourteen benign meningiomas, ten atypical/anaplastic meningiomas, two hemangiopericytomas and one solitary fibrous tumour (SFT) were included. Frozen sections were immunostained using antibodies directed against leukocyte integrins, CD68, CD14, CD2, CD1a, DRC1 and CD34. Their expression was evaluated semi-quantitatively. Ki67 positive cells were counted. Arachnoid membranes served as controls. Arachnoid cells expressed the beta2-integrin subunit and KP1. Beta2 was detected in the tumour cells of 14 meningiomas. In nine cases, this was associated with an alpha-integrin subunit. There was no statistical difference in the expression of beta2 between benign and atypical/anaplastic meningiomas. KP1 was constantly expressed by the tumour cells of meningiomas. It was not expressed by other meningeal tumours. CD34 was detected in the fibrous meningiomas, hemangiopericytomas and the SFT. In each tumour, macrophages were more numerous than T lymphocytes. There was no statistical difference in the density of macrophages and T lymphocytes between the benign and atypical/anaplastic meningiomas. There was no correlation between the Ki67 proliferation index and macrophage infiltration. Meningiomas, through the expression of leukocyte antigens, have a very particular phenotype. The expression of beta2 integrins could play a role in the attraction of immunocompetent cells in the stroma of meningiomas.

Expression of beta1 and beta4 integrins in normal arachnoid membrane and meningiomas.

BACKGROUND: The aim of this work was to study the expression of alpha, beta1, and beta4 integrin subunits in meningiomas. METHODS: Seventeen atypical or anaplastic meningiomas were retrieved from the files of Hôpital de Bellevue, Saint-Etienne, France. They were compared with 17 benign meningiomas consecutively examined in 1997 and 6 schwannomas. The tumors were classified according to standard histologic criteria. Frozen sections were immunostained for alpha1, alpha2, alpha3, alpha4, alpha5, alpha6, beta1, and beta4 integrin subunits; collagen; laminin and fibronectin; cytokeratin; vimentin; neural cell adhesion molecule (NCAM); and MIB-1. RESULTS: The study included 7 fibrous meningiomas, 6 transitional meningiomas, 19 syncytial meningiomas, and 2 secretory meningiomas. The expression of alpha1, alpha3, alpha5, alpha6, and beta1 was constant. The expression of alpha1 was higher in fibrous meningiomas than in syncytial meningiomas. Only in transitional, syncytial, and secretory meningiomas was the expression of alpha2 detected. The expression of alpha2 and beta4 was associated with the expression of cytokeratin in the glandular structures of secretory meningiomas, whereas it was associated with NCAM expression in the whorls of meningothelial meningiomas. The expression of integrin receptors by tumor cells was strongly correlated with that of their respective ligands in the extracellular matrix. In invasive meningiomas, the expression of alpha3 and alpha6 by tumor cells was significantly lower. The higher the MIB-1 proliferation index, the lower the expression of alpha3. The 6 schwannomas expressed only alpha2, alpha3, alpha6, beta1, and beta4 integrins. CONCLUSIONS: Each histologic subtype of meningioma has a specific spectrum of integrin expression. The study of alpha3 and alpha6 may have prognostic value in the assessment of meningiomas. The study of the integrin profile is valuable for the differential diagnosis of fibrous meningiomas and schwannomas.