Expertise in surgical neuro-oncology. Results of a survey by the EANS neuro-oncology section.

Introduction: Technical advances and the increasing role of interdisciplinary decision-making may warrant formal definitions of expertise in surgical neuro-oncology. Research question: The EANS Neuro-oncology Section felt that a survey detailing the European neurosurgical perspective on the concept of expertise in surgical neuro-oncology might be helpful. Material and methods: The EANS Neuro-oncology Section panel developed an online survey asking questions regarding criteria for expertise in neuro-oncological surgery and sent it to all individual EANS members. Results: Our questionnaire was completed by 251 respondents (consultants: 80.1%) from 42 countries. 67.7% would accept a lifetime caseload of >200 cases and 86.7% an annual caseload of >50 as evidence of neuro-oncological surgical expertise. A majority felt that surgeons who do not treat children (56.2%), do not have experience with spinal fusion (78.1%) or peripheral nerve tumors (71.7%) may still be considered experts. Majorities believed that expertise requires the use of skull-base approaches (85.8%), intraoperative monitoring (83.4%), awake craniotomies (77.3%), and neuro-endoscopy (75.5%) as well as continuing education of at least 1/year (100.0%), a research background (80.0%) and teaching activities (78.7%), and formal interdisciplinary collaborations (e.g., tumor board: 93.0%). Academic vs. non-academic affiliation, career position, years of neurosurgical experience, country of practice, and primary clinical interest had a minor influence on the respondents' opinions. Discussion and conclusion: Opinions among neurosurgeons regarding the characteristics and features of expertise in neuro-oncology vary surprisingly little. Large majorities favoring certain thresholds and qualitative criteria suggest a consensus definition might be possible.

[Surgical kyphoplasty for management of axis metastasis: technical note kyphoplastie de C2]. / Traitement par kyphoplastie ouverte d'une métastase de C2 : cas clinique et note technique.

C2 vertebral metastases are seldom encountered. They usually cause disabling pain at the upper cervical level and can also result in life-threatening spinal instability. The technique described herein may provide a valuable minimally invasive option for treating this condition. We report a case of C2 metastasis resulting from gastric adenocarcinoma in a 58-year-old male; since there was no spinal instability, open kyphoplasty was performed at C2, resulting in the healing of the body and the base of the odontoid of the C2 vertebra. The X-ray follow-up more than six months after surgery confirmed the absence of any spinal instability at the craniocervical junction. Open kyphoplasty at C2 provides a means to manage a metastasis located in the body of the C2 vertebra. This method maintains the rotatory function of the upper cervical spine, which seems to be a crucial factor, given the poor prognosis usually associated with this condition.

[Minimally invasive transmuscular approach for the treatment of lumbar far lateral disc herniation]. / Utilisation d'un écarteur musculaire tubulaire dans le traitement chirurgical des hernies discales lombaires extraforaminales.

BACKGROUND: The purpose of this study was to evaluate a minimally invasive surgical technique for the treatment of lumbar far lateral disc herniation. This technique combines the tubular retractor with the operative microscope. OBJECTIVE AND METHODS: This retrospective study analyzed the files of 26 patients: 15 men and 11 women. The average age was 56 years (range, 19-83 years). The most commonly operated level was L3-L4 (46%), then L4-L5 (30.5%) and finally L2-L3 (15.5%). All patients were operated under general anesthesia. The intraoperative radioscopic location was absolutely necessary. A 12-15 mm paramedian incision was made on the side of the herniation (30 mm from the medial line). We then inserted the tubular muscular retraction system followed by the 14 mm diameter working channel. Guided by operating microscope, the articular isthmus was reamed to expose the root and the disc. The disc herniation was then removed after opening and removing the inter-transverse ligament. RESULTS: The average duration of the surgery was 55 min. This operating time decreased as the surgeons gained experience. The radicular pain, estimated using the analogical visual scale, varied from seven before surgery to two during the postoperative period. All the patients were standing up the day after surgery. The average duration of the postoperative stay in the hospital was three days (range, 1-5 days). We noted no complications from the surgical procedure. The average duration of the follow-up was two years (range, 6-36 months). CONCLUSION: This technique combines the advantages of endoscopic surgery (less muscular and osseous damage) and microscope-guided surgery (three-dimensional vision) and provided good functional results in this series.

[Management of tumoral epilepsy in meningioma surgery: Review of the literature and survey of French national practices]. / Gestion de l'épilepsie tumorale dans la chirurgie des méningiomes : revue de la littérature et enquête sur les pratiques nationales.

Prophylaxis or treatment of tumor-associated seizures is adaily concern in neurosurgical practice but is often guided by the surgeon's habits rather than evidence from clinical trials, which is lacking. The present study reviews the literature on the incidence, clinical aspects and treatment of epilepsy and epileptic seizures in patients undergoing surgery for meningioma. Based on the published data, we then performed a French nationwide survey of neurosurgeons' practices regarding perioperative management of meningioma-related epilepsy and epileptic seizures.

Optimization of high-grade glioma resection using 5-ALA fluorescence-guided surgery: A literature review and practical recommendations from the neuro-oncology club of the French society of neurosurgery.

BACKGROUND: When feasible, the surgical resection is the standard first step of the management of high-grade gliomas. 5-ALA fluorescence-guided-surgery (5-ALA-FGS) was developed to ease the intra-operative delineation of tumor borders in order to maximize the extent of resection. METHODS: A Medline electronic database search was conducted. English language studies from January 1998 until July 2018 were included, following the PRISMA guidelines. RESULTS: 5-ALA can be considered as a specific tool for the detection of tumor remnant but has a weaker sensibility (level 2). 5-ALA-FGS is associated with a significant increase in the rate of gross total resection reaching more than 90% in some series (level 1). Consistently, 5-ALAFGS improves progression-free survival (level 1). However, the gain in overall survival is more debated. The use of 5-ALA-FGS in eloquent areas is feasible but requires simultaneous intraoperative electrophysiologic functional brain monitoring to precisely locate and preserve eloquent areas (level 2). 5-ALA is usable during the first resection of a glioma but also at recurrence (level 2). From a practical standpoint, 5-ALA is orally administered 3 hours before the induction of anesthesia, the recommended dose being 20 mg/kg. Intra-operatively, the procedure is performed as usually with a central debulking and a peripheral dissection during which the surgeon switches from white to blue light. Provided that some precautions are observed, the technique does not expose the patient to particular complications. CONCLUSION: Although 5-ALA-FGS contributes to improve gliomas management, there are still some limitations. Future methods will be developed to improve the sensibility of 5-ALA-FGS.

Normal pressure hydrocephalus: long-term outcome after shunt surgery.

BACKGROUND/OBJECTIVE: Little is known about the long-term clinical course and management of patients with normal pressure hydrocephalus (NPH) treated by cerebrospinal fluid (CSF) shunting. METHODS: We retrospectively reviewed records of 55 patients diagnosed with idiopathic NPH (INPH) and treated with CSF shunts, all of whom were followed for more than 3 years after the original shunt surgery. At each annual follow-up visit, the patient was assessed by Folstein Mini Mental State Examination, detailed clinical evaluation of gait and assessment of headache, cognition, gait or urination, as assessed by the patient and relatives. RESULTS: The mean duration of follow-up was 5.9+/-2.5 years. There was an overall sustained improvement among all symptoms. Gait showed the highest maintenance of improvement over baseline (83% at 3 years and 87% at the last analysed follow-up of 7 years), cognition showed intermediary improvement (84% and 86%, respectively), and urinary incontinence showed the least improvement (84% and 80%, respectively). Fifty-three percent of patients required shunt revisions. Indications for revision included shunt malfunction (87%), infection (10%) and change of shunt configuration (3%). Overall, 74% revisions resulted in clinical improvement. CONCLUSIONS: Clinical improvement of patients with NPH can be sustained for 5-7 years in some patients with NPH, even if shunt revision surgery is needed multiple times. With earlier diagnosis and treatment of NPH and the increasing lifespan of the ageing population, the need for long-term follow-up after shunt surgery for NPH may be greater than it was in the past. Monitoring, identification and treatment of shunt obstruction is a key management principle.

[Disappearance of retro-odontoid pseudotumor after C1-C2 transarticular fixation screw]. / Disparition d'une pseudotumeur rétro-odontoïdienne sur instabilité C1-C2 par ostéosynthèse transarticulaire C1-C2.

Atlantoaxial degenerative articular cysts are described in various situations like rheumatoid arthritis, dialysis, and fractures... and in the C1-C2 subluxations of degenerative origin. The treatment of these retro-odontoid tumors does not consist in excision of the pseudotumor but in the reduction of instability by cervical fusion. The procedures are varied and comprise neurological and vascular risks. We report a case of C1-C2 subluxation associated with a pseudocyst compressing the cervical spinal cord, which was treated successfully by transarticular screwing without wiring procedure. This technique has never been used previously in this indication. However, the peroperational risks are less important and the results are similar to those of the other procedures.

[Value of relative cerebral blood volume measurement using perfusion MRI in glioma management]. / Intérêt de la mesure du volume sanguin régional cérébral relatif par IRM de perfusion dans la prise en charge des gliomes.

INTRODUCTION: Neoangiogenesis is a critical feature that can differentiate high-grade from low-grade glioma. Conventional MR imaging does not assess this histological feature accurately. The goal of this study was to evaluate the gain in relative cerebral blood volume measurement using perfusion MRI in the management of cerebral gliomas. MATERIALS AND METHODS: Between 1998 and 2001, 32 histologically proven glial tumors were assessed by perfusion MRI using echoplanar imaging (EPI) and gradient-echo techniques. Relative cerebral blood volume (rCBV) was measured in all patients and compared to histological data. RESULTS: rCBV values were significantly correlated to histological grading in all 32 patients (P<0.001). Mean rCBV values were 8.74 (+/-3.79) for glioblastomas, 7.37 (+/-2.83) for anaplastic gliomas and 0.84 (+/-0.61) for low-grade gliomas. Mean rCBV values were significantly different between low- and high-grade gliomas, making it possible to determine a threshold (2.5-3) that can separate these two types of lesion. In determining the histological grading, rCBV was shown to be significantly more accurate than conventional MRI (P<0.005). CONCLUSION: Perfusion MRI using the EPI technique reliably assesses tumoral neoangiogenesis in gliomas preoperatively. The specificity and sensitivity of this technique make this radiological modality a valuable tool in the assessment of cerebral gliomas.

[Prognostic implications of biologic markers in intracranial meningiomas: 120 cases]. / Implications pronostiques de différents marqueurs biologiques dans les méningiomes intracrâniens: à propos de 120 cas.

UNLABELLED: The recurrence and progression of treated intracranial meningiomas highlights the problem of the type of follow-up that should be used and whether early complementary treatment is indicated. The aim of this study was to evaluate different biochemical markers involved in cell proliferation and transformation to identify new prognostic factors in intracranial meningiomas. Between 1989 and 2003, 120 intracranial meningiomas were studied biochemically. The levels of estrogen receptors (RE), progesterone receptors (RP), cathepsin B (CB), cathepsin L (CL), stefin A (ATA), stefin B (STB), cystatin C (CYSC), urokinase (u-PA), type 1 plasminogen activator inhibitors (PAI-1), cathepsin D (CD) and thymidine kinase activity (TK) were measured in tumor extracts using biochemical assays. RESULTS: Out of 120 meningiomas, 73 were grade I, 39 grade II and eight grade III according to the WHO classification. Of these patients, 17 showed recurrence. The mean follow-up was 47 months. Monofactorial analysis showed that expression of progesterone receptors (RP) had an inverse correlation with recurrence (p=0.0025 %) and that thymidine kinase activity (TK), cathepsin L (CL), the WHO grade and the degree of tumor resection correlated with recurrence (p<0.05). Principal component analysis and linear discriminant analysis confirmed these results. The results of this study confirm the importance of biological parameters (PR, CL, TK) as prognostic factors for the risk of recurrence in intracranial meningiomas.

Time rescaling reproduces EEG behavior during transition from propofol anesthesia-induced unconsciousness to consciousness.

General anesthesia (GA) is a reversible manipulation of consciousness whose mechanism is mysterious at the level of neural networks leaving space for several competing hypotheses. We recorded electrocorticography (ECoG) signals in patients who underwent intracranial monitoring during awake surgery for the treatment of cerebral tumors in functional areas of the brain. Therefore, we recorded the transition from unconsciousness to consciousness directly on the brain surface. Using frequency resolved interferometry; we studied the intermediate ECoG frequencies (4-40 Hz). In the theoretical study, we used a computational Jansen and Rit neuron model to simulate recovery of consciousness (ROC). During ROC, we found that f increased by a factor equal to 1.62 ± 0.09, and δf varied by the same factor (1.61 ± 0.09) suggesting the existence of a scaling factor. We accelerated the time course of an unconscious EEG trace by an approximate factor 1.6 and we showed that the resulting EEG trace match the conscious state. Using the theoretical model, we successfully reproduced this behavior. We show that the recovery of consciousness corresponds to a transition in the frequency (f, δf) space, which is exactly reproduced by a simple time rescaling. These findings may perhaps be applied to other altered consciousness states.

[Intracranial ependymomas in adult patients. Prognostic factors, place of surgery and complementary treatment]. / Ependymomes intracrâniens de l'adulte. Facteurs pronostiques, place de la chirurgie et du traitement complémentaire.

Prognostic factors and optimal therapy for adult intracranial ependymoma are still debated. Available data has been generally collected from retrospective and heterogeneous series including pediatric and spinal cases in particular. The goal of this article is to review and discuss the prognostic factors and the various therapeutic strategies suggested in the literature in light of prognostic and decision making features delineated from a multicentric study conducted in France.

[Intracranial ependymomas in adult patients. Retrospective analysis of 121 cases from the multicentric French study]. / Ependymomes intracrâniens de l'adulte. Analyse rétrospective de 121 cas provenant de l'étude multicentrique française.

Ependymomas are rare intracranial tumors observed in adults. Prognostic factors as well as proper therapeutic management remain controversial. We report a retrospective study of 121 cases intracranial ependymomas diagnosed between 1990 and 2004 in adult patients. Mean age was 46 years with a 1/1 sex-ratio. Supratentorial and infratentorial localization was noted for 41 (33.9%) and 80 (66.1%) patients respectively. Total gross resection was achieved for 62.8% of tumors. WHO staging was grade II for 72.7% and III for 27.3%. Recurrence developed in 41 (33.9%) patients. Median follow-up was 70 months. The 5-year and 10-year overall survivals were 85 and 76% respectively; the respective progression-free survivals were 64 and 43%. At univariate analysis, age, KPS, localization, extent of surgery and histological grade were correlated with overall survival. At multivariate analysis age, location, histological grade and extent of surgery contributed most to prediction of overall survival. Concerning progression-free survival, univariate analysis found age, KPS, localization, extent of surgery, complementary treatment and histological grade to be correlated with recurrence. Multivariate analysis retained extent of surgery, histological grade and complementary treatment as the most important predictors of progression-free survival. This study demonstrated that extent of surgery and tumor grade are the two main prognostic factors in adult intracranial ependymomas with respect to overall and progression-free survival. Furthermore, our data suggest that postoperative radiotherapy significantly increases progression-free survival in patients with incompletely resected grade II tumors.

[Open kyphoplasty for management of metastatic spine fracture]. / Traitement par kyphoplastie à foyer ouvert des métastases rachidiennes.

INTRODUCTION: Metastatic spine fractures are very frequent, often occurring in patients with severe medical conditions. Open kyphoplasty and vertebroplasty are part of the classic management of this of fracture. In certain conditions such as spinal cord compression caused by epidural metastatic cancer or collapse of the vertebral body implying a local kyphosis, surgery should allow decompression of the spinal cord and stabilisation of the spine in a simple act. The purpose of this study is to assess a surgical technique combining surgical decompression by laminectomy frequently associated with posterior transpedicular instrumentation and at the same time, an open kyphoplasty to stabilize the anterior part of the spine. MATERIAL AND METHODS: The same procedure was performed in 14 patients during an 18-month period. The average age of the patients was 54 years. All patients suffered severe pain before the surgical procedure (VSA mean: 7). Neurological deficiency was noted in 10 of the 14 patients with this spinal cord compression. Nineteen vertebrae were treated; a short posterior instrumentation was necessary in 11 patients. The average operative time was 90 minutes. Of the patients with neurological deficiency, the clinical status improved after surgery in all. The average VSA of this series 3 days after surgery was 2. The mean quantity of PMMA injected was 7 cc. Two PMMA leaks, one in the intervertebral disc and one forward, were identified on the postoperative CT scan. The average hospital stay was 7 days. CONCLUSION: This procedure enables surgical decompression, vertebral body consolidation and consequently spinal stabilization of the spine. We did not have any complications related to this procedure which, particularly for the elderly population, is an attractive alternative to major surgery such as vertebrectomy.

[Cranial vault chondroma: a case report and literature review]. / Chondrome de la convexité: revue de la littérature à propos d'un cas.

Intracranial chondromas are unusual tumors, which most commonly arise from cartilage rets in the synchondrosis at the base of the skull. They are most likely found in the sellar and parasellar regions, usually located extradurally. In rare instances, these tumors originate from the dura mater of the convexity. In these cases their neuroradiological features may mimic other intracranial tumors. We present the case of a 50-year-old male presenting a large parasagittal tumor originating in the frontal convexity. MRI-scans revealed a cavitated tumor strongly enhanced after gadolinium infusion mimicking a parasagittal meningioma. There was no obstruction of the superior sagittal sinus as shown by cerebral angiogram. Total excision was achieved and the postoperative course was uneventful. No complementary treatment was therefore considered. The histological examination diagnosis was chondroma. Radiological workup performed at four years follow-up did not reveal any recurrence of the lesion. Pathogenic, clinico-radiological and therapeutic issues are discussed and the literature reviewed.

[Percutaneous pedicle screw fixation and kyphoplasty for management of thoracolumbar burst fractures]. / Traitement des fractures de type burst de la charnière thoracolombaire par kyphoplastie et ostéosynthèse percutanée.

OBJECTIVE: To evaluate outcome and potential advantages of a percutaneous posterior approach to burst fractures of the thoraco-lumbar junction without neurological complications by means of a technique combining balloon kyphoplasty and percutaneous pedicule screw fixation. METHODS: In this preliminary study patients who suffered traumatic of the thoraco-lumbar junction presented a Magerl type A3 fracture. The mean age of the patients was 64 years (54-78 years). All had a normal neurological examination. A combined technique using balloon kyphoplasty, that allows restoration of the vertebral height and fixation by means of cement injection with percutaneous osteosynthesis was performed as a minimal invasive alternative treatment. Mean follow-up (plain radiograph and CT scan, pain assessment) was 12 months (range 5-14 months). RESULTS: All patients experienced an early pain relief, successfully mobilized on day 1 after surgery and discharged after a mean stay of 4.5 days. Immediately postoperatively the mean vertebral height restoration was 11.5% and the reduction of the kyphotic angle was 9 degrees. Those results were maintained over the complete follow-up period. Only one patient required analgesic treatment with weak opioids (step II of the WHO pain ladder) 3 months after surgery. CONCLUSIONS: The treatment of burst fractures of the thoraco-lumbar junction with no neurological complication by associating minimally invasive techniques results in good fracture reduction and stabilisation. The main advantage of this approach is to shorten the hospital stay.

[Endovascular treatment of idiopathic intracranial hypertension. Analysis of eight consecutive patients]. / Traitement endovasculaire de l'hypertension intracrânienne bénigne étiquetée "idiopathique". Analyse de huit cas consécutifs.

INTRODUCTION: Optic nerve sheath fenestration or ventricular shunting are classically proposed after failure of medical treatment. Idiopathic intracranial hypertension is caused by venous sinus obstruction in an unknown percentage of cases. Recently, endoluminal venous sinus stenting was proposed as an alternative treatment. PATIENTS AND METHOD: Between September 2003 and December 2004, eight consecutive patients with a diagnosis of idiopathic intracranial hypertension underwent MRI venography and direct retrograde cerebral angiography. RESULTS: There were five females and three males aged 22 to 55 years. All patients had vision disorders. The cerebrospinal fluid pressure ranged from 27 to 45 mmHg with normal composition. All patients presented at least one sinus stenosis. Endovascular stenting of the stenotic venous sinus was performed under intravenous heparin administration. Anti-platelet therapy was administered for 3 months post treatment. Intra-sinus pressures were invariably reduced by stenting. Mean follow-up was 18 months. All patients improved clinically. The cerebrospinal fluid pressure had normalized at 3-month follow-up in all patients. In all patients, multidetector row CT-angiography or MRI venography was performed at 3-, 6- and 12-month follow-up and demonstrated the patency of the stent. DISCUSSION: The importance of venous sinus disease as a cause of idiopathic intracranial hypertension is probably underestimated. Patients with idiopathic intracranial hypertension should be evaluated with direct retrograde cerebral venography and manometry. In patients with venous sinus lesions, treatment by an endoluminal venous sinus stent is a safe and effective alternative for amenable lesions.

[Intracranial ependymomas in adult patients. Diagnosis and histological prognostic factors]. / Ependymomes intracrâniens de l'adulte. Diagnostic histologique et facteurs histopronostiques.

BACKGROUND: Intracranial ependymomas are rare in adults and histopathological prognostic factors are poorly determined. PURPOSE: A retrospective multicentric study was conducted in France in order to assess the prognostic value of histology. MATERIAL: Between 1990 and 2004, 216 adult patients with newly diagnosed ependymomas were treated in 19 French centers. Eligibility required institutional histopathological confirmation of an ependymoma and available clinical history and MRI features (see comparison paper). METHODS: Histological preparations and one paraffin embedded block from each patient were sent to Pr D. Figarella-Branger in Marseille. Central review by four neuropathologists (D. Figarella-Branger, A. Maues de Paula, C. Fernandez and A. Jouvet) was performed. Specimens for which all pathologists agreed with the histological diagnosis of ependymomas were included, whereas cases for which all disagree were excluded and reclassified. In the event of doubt and/or discrepancies between pathologists immunostaining was performed in order to reach a consensus diagnosis. Diagnostic of ependymomas was confirmed in 121 cases (56%). In theses cases, ependymomas were classified according to the WHO system (subtype and grade). The potential prognostic value (overall survival OS and disease free survival DFS) of the following histological parameters was examined: perivascular pseudorosettes, ependymal rosettes, hyalinized vessels, mitotic index, microvascular proliferation, necrosis, area of increased cellularity, nuclear atypia, brain invasion and Mib-1 labelling index. RESULTS: Among the 121 ependymomas, 88 were grade II (47 classic, 17 cellular, 2 papillar, 6 clear cells and 16 tanicytic) and 33 grade III. WHO grading, occurrence of microvascular proliferation, necrosis, nuclear atypia and high proliferative index were correlated with both OS and DFS. Moreover, quantification of certain parameters enabled a reproducible grading system correlated with both OS and DFS.

Carmustine wafer implantation for high-grade gliomas: Evidence-based safety efficacy and practical recommendations from the Neuro-oncology Club of the French Society of Neurosurgery.

There is a growing body of evidence that carmustine wafer implantation during surgery is an effective therapeutic adjunct to the standard combined radio-chemotherapy regimen using temozolomide in newly diagnosed and recurrent high-grade glioma patient management with a statistically significant survival benefit demonstrated across several randomized clinical trials, as well as prospective and retrospective studies (grade A recommendation). Compelling clinical data also support the safety of carmustine wafer implantation (grade A recommendation) in these patients and suggest that observed adverse events can be avoided in experienced neurosurgeon hands. Furthermore, carmustine wafer implantation does not seem to impact negatively on the quality of life and the completion of adjuvant oncological treatments (grade C recommendation). Moreover, emerging findings support the potential of high-grade gliomas molecular status, especially the O(6)-Methylguanine-DNA Methyltransferase promoter methylation status, in predicting the efficacy of such a surgical strategy, especially at recurrence (grade B recommendation). Finally, carmustine wafer implantation appears to be cost-effective in high-grade glioma patients when performed by an experienced team and when total or subtotal resection can be achieved. Altogether, these data underline the current need for a new randomized clinical trial to assess the impact of a maximal safe resection with carmustine wafer implantation followed by the standard combined chemoradiation protocol stratified by molecular status in high-grade glioma patients.