Posterior fossa ependymoma in children: A long-term single-center experience.

INTRODUCTION: Ependymomas in the posterior fossa have poor prognosis. This study reports a single-center pediatric series, focusing on the value of surgical resection. MATERIAL AND METHODS: A single-center retrospective study included all patients operated on by the senior author (CM) for posterior fossa ependymoma from 2002 to 2018. Medical and surgical data were extracted from the hospital's medical database. RESULTS: Thirty-four patients were included. Age ranged from 6 months to 18 years, with a median of 4.7 years. Fourteen patients underwent initial endoscopic third ventriculocisternostomy before the direct surgical resection. Surgical removal was complete in 27 patients. There were 32 surgeries for second-look, local recurrence or metastasis despite complementary chemotherapy and/or radiotherapy. Twenty patients were WHO grade 2 and 14 grade 3. Sixteen patients showed recurrence (47%). Overall survival was 61.8% at a mean 10.1 years' follow-up. Morbidities comprised facial nerve palsy, swallowing disorder, and transient cerebellar syndrome. Fifteen patients had normal schooling, 6 had special assistance; 4 patients reached university, 3 of whom experienced difficulties. Three patients had a job. CONCLUSION: Posterior fossa ependymomas are aggressive tumors. Complete surgical removal is the most important prognostic factor, despite risk of sequelae. Complementary treatment is mandatory, but no targeted therapy has so far proved effective. It is important to continue the search for molecular markers in order to improve outcomes.

A new approach of crenellated fronto-orbital advancement for the management of trigonocephaly: Technical note.

Trigonocephaly is a craniosynostosis characterized by a premature fusion of the metopic suture associating a characteristic triangular head shape, with a frontal medial crest and hypotelorism. Various techniques have been described for its surgical treatment which is usually performed during the first year of life. However, there might be cases with a late referral, after the age of one year. One of the technical issues with a fronto-orbital advancement surgery in a child over one year of age is that there is a significant risk of persistent residual bone defects. This article describes a surgical technique of crenellated fronto-orbital advancement for correcting trigonocephaly in children over one year of age, allowing to reduce residual bone defects.

Surgical management of posterior fossa medulloblastoma in children: The Lyon experience.

INTRODUCTION: Modern approach for the treatment of posterior fossa medulloblastomas remains a challenge for pediatric neurosurgeons and pediatric oncologists and requires a multidisciplinary approach to optimize survival and clinical results. MATERIAL AND METHODS: We report the surgical principles of the treatment of posterior fossa medulloblastomas in children and how to avoid technical mistakes especially in very young patients. We also report our experience in a series of 64 patients operated from a medulloblastoma between 2000 and 2018 in Lyon. RESULTS: All patients had a craniospinal MRI. Eighty-one percent of the patients (n=50) had strictly midline tumor while 19% (n=14) had lateralized one. Eleven percent (n=7) had metastasis at diagnosis on the initial MRI. Forty-one percent (n=29) had an emergency ETV to treat hydrocephaly and the intracranial hypertension. All patient underwent a direct approach and a complete removal was achieved in 78% (n=58) of the cases on the postoperative MRI realized within 48h postsurgery. Histological findings revealed classical medulloblastoma in 73% (n=46), desmoplastic medulloblastoma in 17% (n=11) and anaplastic/large cell medulloblastoma in 10% (n=7). Patients were classified as low risk in 7 cases, standard risk in 30 cases and high risk in 27 cases. Ninety-six percent (n=61) of the patient received radiotherapy. Seventy-six percent (n=48) received pre-irradiation or adjuvant chemotherapy. At last follow-up in December 2018, 65% (n=41) of the patient were in complete remission, 12% (n=8) were in relapse and 27% (n=15) had died from their disease. The overall survival at five , ten and fifteen years for all the series was of 76%, 73% and 65.7% respectively. CONCLUSIONS: Medulloblastomas remain a chimiosensible and radiosensible disease and the complete surgical removal represents a favorable prognostic factor. The extension of surgery has also to be weighted in consideration of the new biomolecular and genetic knowledge that have to be integrated by surgeons to improve quality of life of patients.

Emissary veins and pericerebral cerebrospinal fluid in trigonocephaly: do they define a specific subtype?

INTRODUCTION: The premature fusion of the metopic suture may be associated with the presence of emissary veins (EV) and abnormally large pericerebral cerebrospinal fluid (CSF) spaces which suggest an associated focal disturbance in CSF dynamics. The incidence of such findings and their potential significance in terms of management of the disease have not been fully elucidated. The aim of this study is to investigate whether these phenomena identify specific subtypes of trigonocephaly. In such a direction, we evaluated the volume of the pericerebral CSF spaces and their relationship to the morphology ("Ω," "V," or flat type) of the prematurely fused metopic suture and to the value of the interfrontal angle value on the grounds of computed tomographic (CT) scan examinations. METHOD: The preoperative brain CT scans of 74 children (52 boys, 22 girls) with trigonocephaly who had undergone fronto-orbital remodeling were evaluated. The volume of the pericerebral CSF spaces and the value of the interfrontal angle were calculated. The type of intracranial notch was studied and classified according to its shape on the preoperative CT scan: a groove "Ω," a ridge/"V" ridge or absent when flat and evidence of emissary veins related to the abnormally fused suture. RESULTS: Preoperatively, an endocranial metopic groove or ridge was seen in 70% of the children. Emissary veins were identified in 34 of 74 patients (45%), at a mean distance of 2.04 cm (1.18-2.94 cm) from the nasion. The presence of large pericerebral CSF spaces significantly correlated with the presence of EV (p < 0.05), with the "Ω" type (p < 0.05) and with interfrontal angles under 134° (p < 0.005). CONCLUSIONS: Metopic suture early fusion shows an association between EV, pericerebral CSF spaces, and the "Ω" groove appearance of the suture. This association identifies a specific subgroup in which the presence of emissary veins and large pericerebral CSF spaces is an indicator of local venous hypertension due to the sagittal sinus constriction within an osseous groove created by the abnormal suture fusion process. The implications for the surgical management and long-term results as compared to trigonocephalic children with small or absent normal peripheral spaces and EV are still to be determined.

Cranioplasty for bone defects after craniosynostosis surgery. Case series with literature review.

INTRODUCTION: Surgical treatment of craniosynostosis in children may generate secondary cranial vault defects by incomplete ossification process. The incidence of cranial defects after craniosynostosis surgery is poorly reported in the literature with a variable incidence of 0.5% to 18.2%. To better understand the impact and management of the cranial defects after craniosynostosis surgery, we selected and reviewed al cranioplasties that met this criterion between 2002 and 2019. PATIENTS AND METHOD: We found 41 patients (28 M and 13 F) operated between January 2002 to January 2019 who underwent cranioplasty for cranial defects secondary to craniosynostosis surgery in the infancy. All patient were at least 5 years old (range 5 to 17 years, median 11). The indication was aesthetic in 28 patients and for headaches, learning difficulties or changes in the cerebral blood flow in 13 patients. The material used in cranioplasty was the poly-methyl-methacrylate (PMMA) in 40 patients and customized porous hydroxyapatite (CPHA) in 1 patient. RESULTS: The mean follow-up period after cranioplasty was of 37 months (range 2 to 125 months, median of 27 months). In the postoperative period there were no mortality nor neurological complications. There were 3 cases (7%) of superficial local postoperative wound infection but with no evidence of long-term infection. The long-term CT scan follow-up showed no material migration, dislocation or fractures. CONCLUSION: Considering the characteristics of the cranial vault after craniosynostosis surgery the treatment by cranioplasty with heterologous materials appears to be feasible thus avoiding donor site morbidity. For selected cases with small defects, our experience shows that the use of PMMA may be a safe alternative for the cranial vault repair in children older than 5 years.

Positional cranial deformation in children: A plea for the efficacy of the cranial helmet in children.

BACKGROUND: Cranial deformations have historically aroused the interest of people worldwide. One of the more debated points about positional plagiocephaly is the choice of the treatment. In this article, the senior author (CM) shares his experience on almost 30 years of use of the helmet molding therapy in children with deformation plagiocephaly. METHODS AND POPULATION: We retrospectively and systematically reviewed the cases of 2188 patients (75% males and 25% females) presenting positional head deformity and treated between 1991 and 2013 with a cranial helmet. To assess the effectiveness of the helmet, we compared the cranial index in bilateral plagiocephaly and the Cranial Diagonals Difference (CDD) in unilateral plagiocephaly at the beginning and at the end of the treatment. RESULTS: The cranial indexes ranged between 94.4% and 124.2% before the treatment and decreased significantly between 86.8% and 121.4% after the treatment (P<0.01). The CDD ranged between 0.3 cm and 4.5 cm with an average of 1.50±0.54 cm before the treatment and decreased significantly between 0.1 cm and 2.5 cm with an average of 0.72±0.37 cm after the treatment (P<0.01). For unilateral plagiocephaly, at the beginning of the treatment, 2.5% children presented a mild plagiocephaly, 19.6% a moderate plagiocephaly and 77.9% a severe plagiocephaly. At the end of the treatment, the deformation was classified as mild in 40.2% children, moderate in 44.3% children and severe in 15.5% children with significantly less children in the most severe subgroups (P<0.01) Facial symmetry pre-existed before the treatment in 13.7% of children. This rate was significantly increased at the end of the treatment to 66.7% (P<0.01). In only 8 cases (0.2%), the helmet therapy did not allow to obtain correct clinical results and a surgical posterior cranial remodeling was performed. CONCLUSIONS: The results observed in this series confirms that cranial helmet is a simple and well tolerated alternative which bring satisfying results. Its success implies a good collaboration with parents and a management both by orthoptist, physiotherapist and doctor. Nevertheless, it remains many controversies in the literature concerning in particular long-term cosmetic and functional outcomes. A long-term multicentric prospective study could enable to remove doubts.

[Neuropsychological consequences of craniosynostosis: Non-syndromic scaphocephaly]. / Le retentissement neuropsychologique de la craniosténose : cas de la scaphocéphalie non syndromique.

BACKGROUND: Scaphocephaly increases the rate of some modifications of cognitive and mood profile in a manner that remains to be elucidated. OBJECTIVE: We aimed to describe the impact of scaphocephaly on neuropsychological profile and more particularly on the executive functions. PATIENTS AND METHODS: An experimental group of 19 children older than 5 years, operated on for scaphocephaly, was compared with a control group of 10 children operated on for trigonocephaly, using IQ tasks, attention tasks and mood scales. A group of 6 children from 2 to 4 years old, operated on for scaphocephaly, and a group of 6 children with non-operated scaphocephaly are also described. RESULTS: Both the experimental group and the control group showed unchanged IQ, whereas attention deficit and anxiety disorder were more frequent in the experimental group. Cognitive profiles differed between groups, with a higher rate of impaired inhibitory control of visual processing in the scaphocephaly group, contrasting with a higher rate of impaired auditory verbal working memory in the trigonocephaly group. Comparable profiles were also found in groups of younger or non-operated children with scaphocephaly. CONCLUSIONS: Many children with scaphocephaly must cope with a specific neuropsychological profile throughout development. This study suggests the interest for these children and their families of specific follow-up in reference centers.

Sagittal suture craniosynostosis or craniosynostoses? The heterogeneity of the most common premature fusion of the cranial sutures.

BACKGROUND: Scaphocephaly is usually defined as the deformation of the skull resulting from the premature fusion of the sagittal suture. It is the most common type of craniosynostosis, and can be easily recognized on simple clinical examination. Its pathophysiology is easy to understand and to confirm on neuroradiological examination. In contrast, surgical indications are still somewhat controversial, the dispute mainly concerning therapeutic versus esthetic objectives. In recent years, however, several studies have challenged these basic and relatively simplistic interpretations of the pathophysiology of the condition. MATERIALS AND METHODS: To assess the heterogeneity of scaphocephaly, we reviewed cases of scaphocephaly operated on at the Hôpital Femme-Mère-Enfant, Lyon University Hospital, France during a 10-year period (2008-2017) and performed a review of the literature on scaphocephaly and sagittal suture closure. RESULTS: During the 10-year period, 401 children were operated on for a scaphocephaly at the Hôpital Femme Mère Enfant, Lyon University Hospital. Mean age at surgery was 1.14 years, for a median 0.7 years (range, 4 months to 8. 5 years). Several subtypes could be distinguished according to morphology, intracranial findings on imaging, patient age, and etiology associated to the sagittal synostosis. Two main surgical techniques were used to correct the malformation, depending on patient age, type of deformation and the surgeon's preference: cranial vault remodeling with occipital pole widening, with the patient in a prone position, and parietal enlargement with or without forehead remodeling, in dorsal decubitus. CONCLUSIONS: The complexity and heterogeneous nature of sagittal synostoses depend on different pathogenic mechanisms leading to and interfering with the skull abnormalities: abnormalities of CSF dynamics, possibly associated with systemic alterations, accounting for the varied postoperative morphological and functional course, in terms of cognitive impairment and late complications (notably intra-cranial pressure elevation). However, the real impact of such heterogeneous clinical presentations on surgical indications and surgical results remains to be elucidated.

[Psychological support for children operated on for craniosynostosis and their family. Some thoughts for the craniofacial surgeon]. / Suivi psychologique des enfants opérés de craniosténoses et de leurs proches. Quelques éléments de réflexions pour le chirurgien craniofacial.

What is the impact on child and family when they receive a diagnosis of craniostenosis? And what is the impact of surgery? What is the role of the clinical psychologist in accompanying the child and family, especially during hospital stay and surgery time? We present a few thoughts that help understand the psychological processes at work in case of craniostenosis, giving a little hint of the impact on the life of the child and family - which surgeons, preoccupied by more technical questions, sometimes tend to overlook.

[Why a hydroxyapatite cranioplasty can be used to repair a cranial bone defect in children: Experience of 19 cases]. / Pourquoi peut-on utiliser une plastie en hydroxyapatite pour réparer une perte de substance osseuse de la boîte crânienne chez les enfants : expérience à propos de 19 cas.

INTRODUCTION: The use of an autologous bone graft to repair a cranial bone defect is sometimes impossible in pediatric cases. CUSTOMBONE® made with hydroxyapatite is a good alternative in these indications for neurosurgeons. MATERIAL AND METHODS: We present a pediatric series of 19 children who benefited from a cranioplasty using CUSTOMBONE®. Their ages ranged between 8 months and 13 years with a mean of 6 years and 2 months. The most frequent indication was a cranioplasty after a post-traumatic decompressive craniectomy. RESULTS: No complications were reported. Cosmetic outcome was satisfactory in all patients. Only one plasty needed to be changed after a severe head trauma during the postoperative period. The assessment of cerebral blood flow was improved in all patients postoperatively. Complete ossification of the plasty is a long process. The mean time for the ossification to begin was 13 months (range: 3-22 months). The mean follow-up was 2.7 years. DISCUSSION: The excellent integration of the prosthesis is related to the accuracy of the reconstruction of the preoperative model. The minimum thickness of the plasty (4mm) could represent a challenge in very young children. One limitation is the cost, which remains high. CONCLUSION: CUSTOMBONE® met the criteria of protection and restoration of the normal intracranial physiology with good cosmetic results, which are necessary qualities for excellent clinical outcome.

Pre-radiation chemotherapy improves survival in pediatric diffuse intrinsic pontine gliomas.

BACKGROUND: The median survival of patients with diffuse intrinsic pontine glioma (DIPG) remains less than 1 year. The BSG 98 pre-irradiation chemotherapy protocol showed a significant increase in overall survival. In contrast to current treatment strategies, patients did not have to undergo surgical stereotactic biopsy, which can sometimes lead to complications, to be included in this protocol. MATERIALS AND METHODS: We retrospectively reviewed all the cases of DIPG that were treated in our department from September 15, 2004 to September 15, 2014. We compared the group of patients who followed our BSG 98 protocol to those who were treated with new targeted therapy protocols where systematic biopsy was required. RESULTS: Patients in the BSG 98 protocol were treated with BCNU, cisplatin, and methotrexate, followed by radiation at disease progression. Targeted therapy protocols included radiation therapy along with treatment by erlotinib, cilengitide, or an association of nimotuzumab and vinblastine. Sixteen patients were treated with the BSG 98 protocol, and 9 patients were treated with new targeted therapy protocols. Median overall survival was significantly higher in the BSG 98 group compared to the targeted therapy group (16.1 months (95 % CI, 10.4-19.0) vs 8.8 months (95 % CI 1.4-12.3); p = 0.0003). An increase in the median progression-free survival was observed (respectively, 8.6 vs 3.0 months; p = 0.113). CONCLUSION: The present study confirms that the BSG 98 protocol is one of the most effective current treatment strategies for DIPG. It may be used as the control arm in randomized trials investigating the use of innovative treatments and may be proposed to families who are averse to biopsy.

[Our experience about the use of resorbable plates in the treatment of craniostenosis]. / Notre expérience de l'utilisation des plaques résorbables dans le traitement des craniosténoses.

INTRODUCTION: The use of resorbable plates increases for craniosynostosis surgery. This material, based on polymere (PLA, PGA) can replace steel wire and non resorbable plates. A few studies present surgical results about the use of this material with a long follow-up. We present our ten years experience of using resorbable material for craniosynostosis treatment in children. METHODS: Between 2002 and 2012, we operated 283 craniosynostosis (98 scaphocephalies, 55 trigonocephalies, 79 plagiocephalies et 51 craniofaciostenoses). Among these surgeries, 211 were realized with resorbable material (plates and screws). Different criteria were observed: the esthetic result, the infection rate, the re-intervention, the bone defects and the inflammatory granuloma. RESULTS: Among the 211 craniosynostosis, we found 62 plagiocephalies, 66 scaphocephalies, 50 trigonocephalies, 33 craniofaciostenoses. All the reconstructions were realized with the same resorbable material (Macropore by Medtronic). The rate of complications was low: one scar infection without participation of material for two patients (0.9%), a pseudo-meningocele for two patients (0.9%), epilepsy for four children (1.8%) and bone defect for 15 (7%). We observed no granuloma for these patients. CONCLUSION: Our experience of ten years using resorbable material is very satisfactory. This material permits to realize solid and esthetic reconstructions with a low rate of infection without dangerous reaction for children in young age.

Cranial vault expansion with the split bone flap technique in shunt-related craniosynostosis.

INTRODUCTION: Shunt-related craniosynostosis causing craniocerebral disproportion represents a particular complication of the treatment of hydrocephalus. When the modification of the shunt opening pressure does not improve the symptomatology, surgery for correction of craniocerebral disproportion is indicated. We present the results and advantages of the split bi-frontal bone technique that is a modification of the previous used frontal bone advancement technique. PATIENTS AND METHODS: We retrospectively reviewed 5 patients with iatrogenic craniosynostosis treated in our institution from 1995 to 2012. A splitting bi-frontal bone flap that is left floating posteriorly was performed to increase the cranial volume. RESULTS: All patients were cured. This technique increases the volume of the skull favoring the expansion of the brain and allows good cosmetical results. No perioperative complications were reported. DISCUSSION: The fact that the brain has a more appropriate volume allows the disappearance of the clinical symptomatology related to the split ventricle syndrome. The advantage is the respect of the fronto-orbital shape in children and adults with the same results of the classic frontal advancement in terms of volume expansion. The study of cerebral blood flow confirms the increase of the cerebral blood perfusion and the improvement of the regional cerebral blood flow in borderline regions. We preconize, for the treatment of slit ventricle syndrome, the bi-frontal split technique in children and adults for its efficacy, the low rate of complications and the respect of aesthetical constraints.

Decompressive craniectomy in the treatment of post-traumatic intracranial hypertension in children: our philosophy and indications.

Decompressive craniotomy (DC) in children is a life-saving procedure for the treatment of refractory intracranial hypertension related to traumatic, ischemic and infectious lesions. Different surgical procedures have been proposed including uni or bilateral hemicraniectomy, bi-frontal, bi-temporal, or bi-parietal craniotomies. DC can avoid the cascade of events related to tissue hypoxia, brain perfusion reduction, hypotension and the evolution of brain edema that can be responsible for brain herniation. The monitoring of intracranial pressure (ICP) is very important to take a decision as well as the value of Trans cranial Doppler (TCD). Repeated TCD in the intensive care unit give important information about the decrease of the cerebral perfusion pressure (CPP) and facilitates the decision making. The important question is about how long time we have to wait before to perform the DC. Three conditions can be distinguished: 1) ICP stable and TCD with good parameters: the decision can be postponed; 2) ICP>20 mmHg with good TCD and without clinical signs of deterioration: the decision can be postponed; 3) ICP>20 mmHg with altered CPP and degraded TCD value and clinical signs of brain herniation: the surgical procedure is indicated. The decision of a ventricular drainage can also be discussed but in cases of slit ventricles it is preferable to realize a DC to avoid the problems of multiple taps without finding the ventricular system. In some very specific situations, DC has to be contraindicated. The first one is a prolonged cardiopulmonary arrest with a no-flow longer than 15 minutes and irreversible lesions on the TCD or on the CT-scan. The second most common situation is a patient with GCS of 3 on admission associated with bilaterally fixed dilated pupils. In this case TCD is very useful to document the decrease or the absence of diastolic flux that indicates a very poor cerebral perfusion. In case of severe polytraumatism with multiorgan failure, especially in very severe hemorrhagic shock with incontrollable coagulopathy, the realization of DC is definitely hazardous with y a high risk of cardiac arrest during the surgical procedure. The decision to realize a hemicraniectomy or a bi-frontal craniotomy is related to the presence or not of associated traumatic lesions as hemorrhagic contusions or a sub-dural or extradural hematoma. In cases of diffuse cerebral edema the bi-frontal bone flap is indicated. In all cases a closure of the dura mater with a large dural patch has to be performed avoiding compression of the nervous system. Our results showed a mortality rate of 18%. Eighty percent of the survivors have a good quality of life but only 43% in a scholar age could attend a normal program. Patients treated with DC need a long follow-up and an important rehabilitation program to improve their quality of life. Our report shows that DC in children is effective to control the post-traumatic intracranial hypertension but a long follow-up is recommended to access the sequels and quality of life of these patients.

Tectal plate tumours. Our experience with a paediatric surgical series.

INTRODUCTION: Exophytic tectal plate tumours are a particular kind of brain stem tumour that can be treated with microsurgical resection. This paper reports our surgical experience with a paediatric series stressing and underlines the fact that this surgery can be possible because the rate of surgical mortality is low in experienced hands with acceptable morbidity. MATERIAL AND METHODS: From 1997 to 2010, 27 patients were treated for exophytic tectal plate tumours. The clinical symptomatology was characterized by an intracranial hypertensive syndrome in 77% of cases, visual disorders in 36% of cases and a Parinaud's syndrome in 12% of cases. All patients were studied using a pre-operative cranio-spinal MRI with and without gadolinium. Hydrocephalus was present in 20 cases treated with a VP shunt in 6 cases and an ETV in the other cases. The surgical removal was total in 60% of cases, partial in 28% of cases and only a large biopsy in 12% of cases. From an histological point of view benign gliomas were diagnosed in 84% of cases and in 16% of cases were classified as WHO grade II and III. Eight patients needed complementary treatment, four with chemotherapy and four with chemotherapy associated to radiotherapy. As a surgical complication two patients had hydrocephalus, one patient had a sub-dural acute haematoma, two patients had an infectious complication requiring surgical treatment and antibiotic therapy, and 5 patients a mechanical shunt dysfunction. No post-surgical mortality was observed. RESULTS: The most recent results after a median survival of 4.3 years show that 22 patients are still alive while 5 patients died of a progressive disease. Twenty patients in school age continue to follow a normal school programme but 10 patients need assistance. CONCLUSION: Exophytic tectal plate tumours can be treated based on a microsurgical approach in paediatric patients. In experienced hands surgery can be performed with an acceptable morbidity and with zero percent mortality. In our experience, the sub-occipital transtentorial approach permits a wide view of the region and safe surgical removal.

Histopathology of pineal germ cell tumors.

Germ cell tumors (GCTs) classically occur in gonads. However, they are the most frequent neoplasms in the pineal region. The pineal location of GCTs may be caused by the neoplastic transformation of a primordial germ cell that has mismigrated. The World Health Organization (WHO) recognizes 5 histological types of intracranial GCTs: germinoma and non-germinomatous tumors including embryonal carcinoma, yolk sac tumor, choriocarcinoma and mature or immature teratoma. Germinomas and teratomas are frequently encountered as pure tumors whereas the other types are mostly part of mixed GCTs. In this situation, the neuropathologist has to be able to identify each component of a GCT. When diagnosis is difficult, use of recent immunohistochemical markers such as OCT(octamer-binding transcription factor)3/4, Glypican 3, SALL(sal-like protein)4 may be required. OCT3/4 is helpful in the diagnosis of germinomas, Glypican 3 in the diagnosis of yolk sac tumors and SALL4 in the diagnosis of the germ cell nature of an intracranial tumor. When the germ cell nature of a pineal tumor is doubtful, the finding of an isochromosome 12p suggests the diagnosis of GCT. The final pathological report should always be confronted with the clinical data, especially the serum or cerebrospinal fluid levels of ß-human chorionic gonadotropin (HCG) and alpha-fetoprotein.

The sub-occipital transtentorial approach revisited base on our own experience.

UNLABELLED: The surgical experience of the sub-occipital approach for treatment of pineal gland and pineal region tumors is reported. This approach was originally proposed by Jamieson and modified by Lapras who by changing the shape of the bone flap obtained the elevation of the occipital lobe which consequently resulted in a better exposition of this deep region. The reason why this approach became the basis for their treatment is particularly related to the personal experience of Lapras who reported his fantastic experience of surgery in this deep area and demonstrated the advantages of the sub-occipital transtentorial approach. MATERIAL: Out of 277 patients operated from 1982 to 2012 in Lyon for a pineal tumor, 233 were treated by a sub-occipital approach: 153 males, 125 females, 75 patients of pediatric age. The majority of patients were operated on in a sitting position which represents a surgical specialty of the anesthesiological school of Lyon. RESULTS: Complete tumor removal was possible in 135 patients (58%) and partial in 60 patients (26%). For 38 patients, it was not possible to establish the quality of surgical resection. The incidence of hemianopsia decreased to less that 2% of cases while the incidence of severe pneumocephaly which requires a prolonged intensive care hospitalization was less than 4% of cases. Mortality related to this surgical approach in the Lyonnais school series was 0% during this period. CONCLUSION: In our experience the sub-occipital transtentorial approach seems to us the best approach for pineal tumors because it permits a large exposition of the pineal region favoring the removal of the tumor with a lateral extension and also for tumors extending low into the posterior cranial fossa. In fact, this is our preferred approach because it has been used in a large majority of cases. However, surgeons have to be familiar with other possible approaches to obtain the best result in terms of removal and also to decrease the rate of sequelae to improve the quality of life of these patients.