Through the orbit and beyond: Current state and future perspectives in endoscopic orbital surgery on behalf of the EANS frontiers committee in orbital tumors and the EANS skull base section.

Introduction: Orbital surgery has always been disputed among specialists, mainly neurosurgeons, otorhinolaryngologists, maxillofacial surgeons and ophthalmologists. The orbit is a borderland between intra- and extracranial compartments; Krönlein's lateral orbitotomy and the orbitozygomatic infratemporal approach are the historical milestones of modern orbital-cranial surgery. Research question: Since its first implementation, endoscopy has significantly impacted neurosurgery, changing perspectives and approaches to the skull base. Since its first application in 2009, transorbital endoscopic surgery opened the way for new surgical scenario, previously feasible only with extensive tissue dissection. Material and methods: A PRISMA based literature search was performed to select the most relevant papers on the topic. Results: Here, we provide a narrative review on the current state and future trends in endoscopic orbital surgery. Discussion and conclusion: This manuscript is a joint effort of the EANS frontiers committee in orbital tumors and the EANS skull base section.

Combined petrosal approach: a systematic review and meta-analysis of surgical complications.

Transpetrosal approaches are known to be associated with a significant risk of complications, including CSF leak, facial palsy, hearing impairment, venous injury, and/or temporal lobe injury. We aimed to evaluate the morbidity of the standard combined petrosal approach (CPA), defined as a combination of the posterior (retrolabyrinthine) and the anterior petrosal approach. We performed a systematic review and meta-analysis of articles reporting on clinical series of patients operated on for petroclival meningiomas through CPA. Studies that used the terminology "combined petrosal approach" without matching the aforementioned definition were excluded as well as clinical series that included less than 5 patients. A total of 8 studies were included involving 160 patients. The pooled complication rates were 3% (95% CI, 0.5-5.6) for CSF leak, 8.6% (95% CI, 4.1-13.2%) for facial palsy, 8.2% (95% CI, 3.9-12.6%) for hearing impairment, 2.8% (95% CI, 0.9-6.5%) for venous complications, and finally 4.8% (95%, 1.2-8.4%) for temporal lobe injury. Contrary to the general belief, CPA is associated with an acceptable rate of complications, especially when compared to alternative approaches to the petroclival area. In view of the major advantages like shorter trajectory, multiple angles of surgical attack, and early tumor devascularization, CPA remains an important tool in the armamentarium of the skull base surgeon.

Basal Cisternostomy for Severe TBI: Surgical Technique and Cadaveric Dissection.

Introduction: Cisternostomy is emerging as a novel surgical technique in the setting of severe brain trauma. Different surgical techniques have been proposed with a variable degree of epidural bone work. We present here the surgical technique as it is currently performed in our Institution. Methods: Anatomical dissection of one adult cadaveric head, injected and non-formalin fixed was perfomed. A large right fronto-temporo-parietal craniotomy was accomplished. Extradural sphenoidal drilling till opening of the superior orbital fissure was performed. The microsurgical anatomy of basal cisternostomy was then explored. Results: A step by step description of the surgical technique, enriched with cadaveric and intraoperative images, was made. Conclusion: Basal cisternostomy is a promising surgical technique that does not necessarily include complex surgical maneuvers. Trained neurosurgeon can safely implement it in their clinical practice.

Endoscopic treatment of spinal arachnoid cysts.

BACKGROUND/OBJECTIVE: Spinal arachnoid cysts (SAC) are intradural lesions, which may provoke a compression of the spinal cord and roots. Endoscopic techniques are increasingly used to minimize the surgical access and the postoperative scar tissue. Shunts may also represent an option. The aim of this paper is to illustrate the technique of endoscopic-assisted fenestration and positioning of a cysto-peritoneal diversion in a thoracic SAC using a flexible endoscope and to perform a systematic literature review on this subject. MATERIAL AND METHODS: We reported our case and we performed a review of the literature, searching for all the adult cases of Type III SACs in English language treated through endoscopic procedures. RESULTS: We found 5 articles matching our search criteria and we included 9 adult patients in our analysis. Six patients were females and the most common localization was the thoracic spine. Six patients underwent selective laminectomies followed by endoscopic fenestration without cyst wall resection. Three patients had a percutaneous endoscopic inspection of the cyst and in two cases a cysto-subarachnoid shunt space was performed. Improvement of pre-operative neurological deficit was reported in six patients, no patients experienced clinical deterioration. The mean follow-up was 22 months and no progression or recurrence was reported. CONCLUSION: The implementation of endoscopy allows a minimally invasive treatments with good visualization of cyst anatomy and precise shunt positioning under real-time guidance. Endoscopy is technically demanding but it can offer similar clinical outcomes when compared to microscopic procedures with a limited rate of post-operative complications.The long-term risk of recurrence should be established by prospective studies.

Petroclival meningiomas: update of current treatment and consensus by the EANS skull base section.

BACKGROUND: The optimal management of petroclival meningiomas (PCMs) continues to be debated along with several controversies that persist. METHODS: A task force was created by the EANS skull base section along with its members and other renowned experts in the field to generate recommendations for the management of these tumors. To achieve this, the task force reviewed in detail the literature in this field and had formal discussions within the group. RESULTS: The constituted task force dealt with the existing definitions and classifications, pre-operative radiological investigations, management of small and asymptomatic PCMs, radiosurgery, optimal surgical strategies, multimodal treatment, decision-making, and patient's counselling. CONCLUSION: This article represents the consensually derived opinion of the task force with respect to the management of PCMs.

A systematic review of the primary squamous cell carcinoma of the external auditory canal: survival outcome based on T-staging and proposal of a new classification.

OBJECTIVE: This study aimed to provide a systematic review on survival outcome based on Pittsburgh T-staging for patients with primary external auditory canal squamous cell carcinoma. METHOD: This study was a systematic review in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines performed until January 2018; pertinent studies were screened. Quality of evidence was assessed using the grading of recommendation, assessment, development and evaluation working group system. RESULTS: Eight articles were chosen that reported on 437 patients with external auditory carcinoma. The 5-year overall survival rate was 53.0 per cent. The pooled proportion of survivors at 5 years for T1 tumours was 88.4 per cent and for T2 tumours was 88.6 per cent. For the combined population of T1 and T2 cancer patients, it was 84.5 per cent. For T3 and T4 tumours, it was 53.3 per cent and 26.8 per cent, respectively, whereas for T3 and T4 tumours combined, it was 40.4 per cent. Individual analysis of 61 patients with presence of cervical nodes showed a poor survival rate. CONCLUSION: From this review, there was not any significant difference found in the survival outcome between T1 and T2 tumours. A practical classification incorporating nodal status that accurately stratifies patients was proposed.

Pediatric cranial osteoblastoma: Technical note of surgical treatment and review of the literature.

Osteoblastoma of the skull is a rare entity, and they account only for 2-4% of all the cases of osteoblastoma. We perform a comprehensive review of the pertinent literature on the subject and we report a case of a 3-year-old girl presenting with a 6-month history of a supraorbital mass and exophthalmos due to an osteoblastoma of the frontal and ethmoid bones involving the orbit and anterior skull base. A 3D printed model of the patient's skull was used for the preoperative planning and reconstruction strategy. Total en-bloc resection of the tumor followed by immediate reconstruction was achieved. No recurrence was detected 3 years after the surgery. Gross total resection is strongly advised with skull osteoblastoma, especially in young age, because of the risk of the recurrence and malignant transformation. 3D printing is proven to be a valuable tool to enhance surgical performance by avoiding complications while achieving total resection with accurate reconstruction. Long-term follow-up is important to detect recurrences and improve the management of these young patients.

Malignant PRES and RCVS after brain surgery in the early postpartum period.

The management of women with brain tumors in the early post-partum period may be demanding as the patho-physiological changes that occur during pregnancy may also manifest in the early post-partum period. The aim of our paper is to report a case of late-onset post-partum pre-eclampsia after brain tumor surgery, complicated by posterior reversible encephalopathy syndrome (PRES) and reversible cerebral vasoconstriction syndrome (RCVS). Hemicraniectomy and intensive care management were necessary to obtain a favorable neurological outcome. The inherent literature on the subject is also analyzed through a systematic research. This is the first case of supratentorial decompressive hemicraniectomy in post-partum PRES, while there has been only one other case of posterior fossa decompression described in this cohort of patients. PRES and RCVS can complicate the neurosurgical management of women in the postpartum period. A careful evaluation of the clinical presentation is necessary as in some particular cases an aggressive medical and surgical treatment is required to obtain a favorable outcome.

Neuroendoscopic septostomy: Indications and surgical technique.

BACKGROUND: Endoscopic septostomy is the treatment of choice for monolateral obstruction of the foramen of Monro. Common causes of this condition include: neoplasms, hemorrages, infections, congenital atresia, idiopathic occlusion. METHOD: All the steps for performing a safe endoscopic pellucidotomy are presented. A brief discussion about the most common technical variations and their rationale is added. CONCLUSION: Endoscopic pellucidotomy is a safe and effective treatment when a thorough understanding of anatomy is achieved.

Chiari I malformation: surgical technique, indications and limits.

BACKGROUND: Chiari malformation type I (CM-I) is a rare disease characterised by herniation of cerebellar tonsils below the foramen magnum with associated anomalies of posterior fossa. We describe here the surgical technique, indications and limits of surgical treatment. METHOD: The authors describe the surgical technique, including: posterior fossa decompression, opening of the foramen of Magendie and duraplasty in case of CM-I. CONCLUSIONS: Posterior fossa decompression plus duraplasty is a safe and effective procedure for patients with CM-I malformation.

[Adult intramedullary gliomas]. / Tumeurs gliales intramédullaires de l'adulte : la série du rapport.

OBJECTIVES: Intramedullary gliomas are rare tumors accounting for less than 4% of all primary central nervous system tumors. The aims of this retrospective multicenter study were to assess their natural outcome as well as management. METHODS AND MATERIALS: We studied 332 patients from 1984 to 2011. Histopathological examination revealed 72% ependymomas (94% were low grade tumors), 24% astrocytomas (29% were high grade tumors), 2.4% mixed gliomas and 1.7% oligodendrogliomas. RESULTS: The mean age at diagnosis was 42.4 years for ependymomas, with male predominance, versus 39.6 years for astrocytomas. Pain was the most common initial presentation. In 20% of cases, astrocytomas were biopsied alone, but more than 80% of ependymomas had surgical resection. Radiotherapy and chemotherapy were reserved for malignant tumors, especially if they were ependymomas. The 5-year survival rate was 76.8% for astrocytomas and 94.5% for ependymomas. Histology, functional status prior to surgery, and tumor grade are among the prognostic factors. CONCLUSION: Our study showed that surgical treatment of gliomas is well codified, at least for ependymomas, but adjuvant treatment continues to play a marginal role in the management even in astrocytomas, which are infiltrative tumors.

[Intramedullary ependymomas: A French retrospective multicenter study of 221 cases]. / Épendymomes intramédullaires : étude rétrospective multicentrique française sur 221 cas.

AIM: Intramedullary ependymomas (IE) are the most frequent intramedullary tumors in the adult population. The gold standard treatment is to obtain gross total removal without any new postoperative neurological deficit. The authors report the results of a multicenter series with a long-term follow-up and the analysis of clinical, radiological, surgical data as well as the complementary treatments. MATERIALS AND METHODS: A retrospective analysis of adult patients with IE operated on between January 1984 and December 2011 at 7 French centers (Bordeaux, Kremlin-Bicêtre, Lille, Lyon, Marseille, Montpellier, Nice, and Nîmes) was performed. The minimal follow-up was 12 months. The clinical evaluation was based on the McCormick classification in the pre and postoperative period at 3 months, 1 and 5 years. RESULTS: Data of 221 adult patients with a pathologically confirmed diagnosis of IE were considered: 134 patients were treated at the Neurosurgical Department of Kremlin-Bicêtre Hospital, 26 were treated at Lille and 61 were treated in the southern region of France (Marseille, Bordeaux, Montpellier, and Lyon). The epidemiological analysis was performed on the entire cohort of patients, while follow-up considerations were made solely on the 134 patients managed at Kremlin-Bicêtre Hospital to obtain homogeneous data. A slight male prevalence was observed (59 % of cases), with an average age of 41.8 years at diagnosis. The mean age at first clinical manifestations was 39.6 years, thus the average duration of symptoms before the diagnosis was 29 months. Neuropathic pain and neurological deficit were the most revealing symptoms in 64 % and 32 % of cases respectively. The localization of the IE was basically cervical in 35.7 %, primarily thoracic in 25.8 % and cervico-thoracic in 22.2 %. The mean tumor length in the sagittal plan was 20.4mm (range 1 to 99mm). A cystic cavity was present in 76.5 % of cases while an intratumoral hemorrhage was detected in 30.3 % of cases. The rate of complete removal was performed in 79.2 % of cases when considering the whole cohort and in 91 % of cases treated at Bicêtre Hospital. In 95 % of cases a WHO grade I or II ependymoma was isolated and in 5 % of cases a WHO grade III. The McCormick scale (MCs) (Lou et al., 2012) [1] was used to rate the degree of preoperative functional impairment in 4 grades. In the immediate postoperative period a worsening of functional capacity was observed. Only 28.8 % of patients had MCs 1 in the immediate postoperative period; 34.8 % had MCs 2; 20.4 % had MCs 3 and 16 % had MCs 4. At 5 years of follow-up (101 patients) the frequencies of grades 1 and 2 were increased: 59 % of patients had MCs 1, 20.8 % had MCs 2, 10,9 % had MCs 3 and 9.3 % had MCs 4. The extension of the lesion on the sagittal plan calculated on the preoperative MRI, was the only predictive factor associated with the immediate postoperative outcome and the short-term follow-up (P=0.04), whereas the preoperative neurological status is the only predictive factor for long-term follow-up (P=0.005). CONCLUSION: Gross total removal remains the mainstay treatment for IE. Early surgery is indicated if the patient is symptomatic or the tumor increases in size. A postoperative regular follow-up is mandatory for at least 10 years due to the risk of recurrence. If a growing residue is detected, a second intervention is recommended without any adjuvant treatment if a WHO grade I lesion is confirmed by the pathological analysis. Complementary treatment should be reserved for high-grade ependymomas or in case of unresectable and progressive residue.

[Intramedullary astrocytomas: A French retrospective multicenter study]. / Astrocytomes intramédullaires : analyse rétrospective française multicentrique.

AIM: The authors report the results of a multicenter retrospective series with a long-term follow-up and the analysis of clinical, radiological, surgical data as well as the complementary treatments in patients with intramedullary astrocytomas (IA). MATERIALS AND METHODS: We performed a retrospective analysis of all the patients with IA operated on between 1984 and 2011 at 7 French centers (Kremlin-Bicêtre, Lille, Lyon, Marseille, Montpellier, Nice, and Nîmes). The minimum follow-up was 12 months. The clinical evaluation was based on the McCormick scale (MCS) results from the pre- and postoperative period. RESULTS: Data from 95 patients with a pathologically confirmed diagnosis of IA were considered: 54 patients were treated at the Neurosurgical Department of Kremlin-Bicêtre Hospital, 8 were treated at Lille and 33 were treated in the south region of France. The epidemiological analysis was performed on the whole cohort of patients while follow-up considerations were made solely on the 54 patients managed at Kremlin-Bicêtre Hospital to obtain homogeneous data. The average age at diagnosis was 35.6 years without significant gender difference (47 % men for 53 % women). The age at first clinical manifestation was 33.7 years. The average duration of the symptoms before the diagnosis was 22.9 months. Neuropathic pain was the principal revealing symptom (76 % of cases). The localization of IA was thoracic in 40 %, purely cervical in 28.4 %. Complete removal was achieved in 29.5 % of cases when considering the whole cohort and in 38 % of cases treated at Bicêtre Hospital. The histological distribution recorded was: grade 1 in 35 %; grade 2 in 35 %; grade 3 in 22 % and grade 4 in 8 %. During the early postoperative period (3 months) a worsening of functional capacity was observed with an increase in the frequencies of ranks 3 and 4 of MCS in 18.4 %. At 5 years follow-up, the frequencies of ranks 1 and 2 were increased. The application of a Cox model for the determination of the relative risk of death for IA grade 1 and 2 (66 patients) showed a probability of survival at 5 years of 78.6 % (CI 95 %: 68.6 %-87.6 %). Survival at 10 years is to 76.8 % (CI 95 %: 62.3 %-84.2 %). CONCLUSION: Surgery is indicated if the patient is symptomatic or the tumor increases in size. A radical excision remains the mainstay of treatment, while searching to preserve the motor function. A total resection was however only possible in 38 % of cases. A regular postoperative follow-up is compulsory and the adjuvant treatment is based on chemotherapy and radiotherapy according to the histological type.

Neuroglial intramedullary tumors: The collaboration between neurosurgeons and neuropathologists.

Intramedullary tumors constitute approximately 5% of spinal tumors and about 80% are of neuroglial origin. We reviewed our series of adult patients with spinal neuroglial intramedullary tumors operated on between 1984 and 2011 at the neurosurgical department of Bicêtre hospital. The histopathological records for 196 patients were retrospectively analyzed. The majority of tumors were ependymomas (68%) and astrocytomas (27.5%). The importance of a proper and detailed neuropathological diagnosis is the key to define patient management. The available literature data about the genetic profiles of these rare tumors are summarized and reviewed.

Cerebral abscess after neuro-vascular embolization: Own experience and review of the literature.

BACKGROUND: Cerebral abscesses are a rare complication after therapeutic neuro-endovascular procedures. METHOD: The aim of this article is to report a case of cerebral abscess after the endovascular embolization of a cerebral aneurysm and to discuss and review all the cases of cerebral abscess secondary to neurovascular embolization described in the literature up to now. RESULTS: A 40-year-old female patient was treated using an endovascular embolization for a ruptured aneurysm of the basilar artery tip. After 2 months she presented with a cerebellar abscess. Antibiotic therapy was started, and a surgical drainage of the collection was performed, with a favorable postoperative outcome. Twelve other cases were reported in the literature, in five cases secondary to the treatment of a cerebral aneurysm, in six cases secondary to a cerebral arterio-venous malformation (AVM) and in one case secondary to a dural arterio-venous fistula (DAVF). The pathophysiology and risk factors of cerebral abscess formation are discussed in detail. CONCLUSIONS: The risk of cerebral abscesses after neuro-endovascular embolization is not negligible, and a growing number of patients affected by this complication may be expected in the near future because of the spreading of neuro-endovascular techniques. The role of prophylactic antibiotic therapy in specific subgroups of patients is still debated.

[Intramedullary hemangioblastomas]. / Les hémangioblastomes intramédullaires.

AIM AND BACKGROUND: Intramedullary hemangioblastomas are rare lesions representing 1 to 5% of spinal tumors. The aim of this study was to review our experience with the surgical management of intramedullary hemangioblastomas. MATERIALS AND METHODS: We performed a retrospective analysis of all the patients with intramedullary hemangioblastomas operated on between 1993 and 2011 in our department. All the patients were screened for Von Hippel Lindau disease. The minimum follow-up was 3 years. The clinical presentation, radiological findings, surgical procedure and outcomes were recorded and analyzed. RESULTS: Our consecutive series included 59 patients with a total of 65 tumors. The mean age at diagnosis was 38 years. Forty-two patients (72.5%) had Von Hippel Lindau disease. The main symptom was pain (58% of cases). The most common location was cervical spinal cord. The average size was 15mm. The resection was complete in 95% cases resulting in clinical improvement in 12% cases, stability in more than 86% of cases and deterioration in less than 2% cases. CONCLUSION: All patients with intramedullary hemangioblastoma should have a screening for the Von Hippel Lindau disease and if the diagnosis is correct, close monitoring should be initiated. Surgical removal is strongly advised in cases of neurological deficits or radiological progression of the tumour.

Intramedullary hemangioblastoma: Microsurgical resection technique.

Spinal hemangioblastomas are benign and highly vascular tumors accounting for 1-5% of intramedullary spinal tumors in surgical series. Surgery is curative in sporadic cases. We present the description of a surgical technique to safely resect an intramedullary hemangioblastoma. A dorsal midline myelotomy provides an excellent exposure of the tumor and identification of the feeding arteries. Interruption of these arteries and precise dissection of the tumor from the cord tissue followed by division of the venous drainage allow the in toto excision of the tumor. Closure of the dorsal myelotomy may be achieved with sequential fusion of the pial and arachnoid edges using a "welding" technique.

Role of preoperative embolization of intramedullary hemangioblastoma.

OBJECT: Hemangiobastomas (HB) are rare lesions accounting for 1 to 5% of all spinal cord tumors. Due to their hypervascular nature, an angiography may be proposed preoperatively in order to identify tumoral vascular anatomy. Preoperative embolization may be indicated to reduce intraoperative bleeding, thus facilitating tumor resection and minimizing surgical risk. The aim of this paper is to report our experience of preoperative embolization in intramedullary hemangioblastomas. METHODS: We performed a retrospective analysis of all patients operated on for intramedullary hemangioblastomas between 1995 and 2014 who had undergone embolization before surgery. RESULTS: Seven patients were analyzed: there were 6 females and 1 male, mean age 43years, 6 patients had Von Hippel-Lindau disease. Four tumors were located in the cervical spine and three in the dorsal spine. The average maximum sagittal diameter was 19mm (range 8-32mm), while the average maximum axial diameter was 11.5mm (range 6-21mm). The embolic agent used was Histoacryl (NBCA). Endovascular embolization was routinely performed the day before surgery. One patient experienced a major preoperative complication with a vertebrobasilar infarctus with consequent unilateral cerebellar syndrome and gait instability. Minor extravasation of embolic agent was observed in two cases. In one of these two cases, there was also the penetration of the embolic agent in the tumor; the resection was impossible due to the hard consistency of the tumor. In the other 6 patients, the resection was total. Six patients had identical preoperative and postoperative McCormick score and one patient shifted to a better score at follow-up. CONCLUSION: Preoperative endovascular embolization is an effective adjunct treatment. It is useful in reducing the surgical bleeding and thus the operative risks. The procedure is not always safe and complications could occur. We recommend preoperative embolization in selected cases.