Radiochirurgie des malformations arterio-veineuses du tronc cerebral stereotactic radiosurgery for brainstem arteriovenous malformations

Introduction: Les malformations artério-veineuses ou angiomes cérébraux sont des anomalies vasculaires congénitales qui se définissent par la présence d’un shunt artério-veineux anormal.Matériels et méthodes: Nous avons mené une étude rétrospective entre Janvier 1992 et Décembre 2010 au service de radiochirurgie de l’hôpital de la Timone, 1557 patients ont été traités par radiochirurgie pour une malformation artérioveineuse dont 61 patients pour une localisation du tronc cérébral (3.91%).Résultats: L’âge moyen de 35.8-/+16.6 ans (4-75).16 patients avaient bénéficié d’une embolisation préradiochirurgicale (26.23%). Le mode de découverte était une hémorragie pour 53 patients (87%). Le volume moyen de traitement était de 1.43+/-1.96 cm3 (0.09-14.20). Le score RBAS était en moyenne de 1.36 +/- 0.34 (0.64-2.35). La dose moyenne de prescription à l’enveloppe l’isodose 50% délivrée était de 22.9 +/-2.9 Gy (12-30), la dose médiane était de 24 Gy).Notre taux d’oblitération global après une ou deux procédures était de 67.27%, pour un délai moyen de suivi est de 56.7 mois+/-43.3 (8.1-251.7). Les facteurs en rapport avec une oblitération) : score RBAS bas (p=0.012), une dose de traitement supérieur à 20Gy (p=0.034). Nous avons eu une mortalité de 1.63% et un pourcentage de saignement après la procédure de 6.55% et 3.2% déficits neurologiques radio-induits.Conclusion: La radiochirurgie est maintenant devenue incontournable dans le traitement des malformations du tronc cérébral même s’il existe un risque hémorragique persistant jusqu’à la guérison (3.5%). Le taux d’oblitération complète est de 67.27%Mots clés: malformations artério-veineuses, tronc cérébral, radiochirurugieEnglish Title: Stereotactic radiosurgery for brainstem arteriovenous malformationsEnglish AbstractIntroduction: Arterioveinous malformations (AVM) or cerebral angiomas are congenital vascular abnormalities which are defined by the presence of abnormal arterio-veinous shunt.Methods:  We lead a retrospective study recruiting 1557 patients treated between January 1992 and December 2010 in the Radiosurgery Unit of La Timone hospital in Marseille. All patients received radiosurgery for management of an AVM, 61 of them being brainstem AVMs (3.91%).Results: Mean age was 35.8 +/- 16.6 years. Sixteen patients underwent arterial embolization before surgery (26.23%). Hemorrhage was the primary onset for 53 patients (87%). Mean volume before treatment was 1.43+/-1.96 cm3 (0.09-14.20). Average RBAS score was 1.36 +/-0.34 (0.64-2.35). Average prescripted dose for 50% delivered iso-dose was 22.9 +/-2.9 Gy (12-30), mean dose was 24 Gy. Our global occlusion rate after one or two treatments was 67.27%, considering an average follow-up of 56.7 months +/- 43.3 (8.1- 251.7). Occlusion related factors were: low RBAS score (p=0.012), received dose higher than 20Gy (p=0.034). Our death rate was 1.63% and our post-procedure bleeding rate was 6.55% with 3.2% of neurological post-procedure deficience.Conclusion: Having regard of remaining hemorrhage risk until complete recovery (3.5%), radiosurgery is nonetheless now a key treatment in the management brainstem AVMS. Complete occlusion rate in our study was 67.27%.Keywords: arteriovenous malformations, brainstem, radiosurger

Neurosurgical application of tractography and cortical - subcortical stimulation

La tractographie et stimulation peropératoire optimiseraient l'exérèse tumorale en conservant la qualité de vie. Les principes du tenseur de diffusion, de la tractographie et de la stimulation cérébrale sont présentés. Une étude de la tractographie des radiations optiques et sa validation sur un modèle lésionnel ont permis de confirmer la faisabilité de la reconstruction. Parmi les algorithmes testés, le plus performant était le " Tensor Line " prédisant un risque de quadranopsie lorsque plus de 5 pour cent des trajectoires avaient une intersection avec le volume lésionnel. La 2ème partie portait sur les processus cognitifs du langage dont la traduction, en stimulation corticale lors de chirurgies éveillées pour 7 patients bilingues. Vingt six zones d'interférences de tâches ont été retrouvées mais aucune n'était spécifique de la traduction qui reste complexe à étudier. Enfin, les perspectives d'intégration de ces 2 techniques sont évoquées à travers 3 cas cliniques.Tractography and intraoperative stimulation would optimize tumor resection preserving the quality of life. The principles of diffusion tensor, tractography and brain stimulation are shown. A study of tractography of optic radiation and validation on a lesion model was able to confirm the feasibility of the reconstruction. Among the tested algorithms, the most effective was the "Tensor Line" predicting a risk of quadrantanopia when more than 5% of the trajectories have an intersection with the lesion volume. The second part focused on the cognitive process of language whose translation by cortical stimulation during awake surgery for 7 bilingual patients. Twenty-six interference tasks area were found but none was specific to the translation, which is complex to study. Finally, the prospects for integration of these 2 techniques are discussed through three clinical cases

Application neurochirurgicale de la tractographie et de la stimulation corticale et sous corticale

La tractographie et stimulation peropératoire optimiseraient l'exérèse tumorale en conservant la qualité de vie. Les principes du tenseur de diffusion, de la tractographie et de la stimulation cérébrale sont présentés. Une étude de la tractographie des radiations optiques et sa validation sur un modèle lésionnel ont permis de confirmer la faisabilité de la reconstruction. Parmi les algorithmes testés, le plus performant était le " Tensor Line " prédisant un risque de quadranopsie lorsque plus de 5 pour cent des trajectoires avaient une intersection avec le volume lésionnel. La 2ème partie portait sur les processus cognitifs du langage dont la traduction, en stimulation corticale lors de chirurgies éveillées pour 7 patients bilingues. Vingt six zones d'interférences de tâches ont été retrouvées mais aucune n'était spécifique de la traduction qui reste complexe à étudier. Enfin, les perspectives d'intégration de ces 2 techniques sont évoquées à travers 3 cas cliniques.Tractography and intraoperative stimulation would optimize tumor resection preserving the quality of life. The principles of diffusion tensor, tractography and brain stimulation are shown. A study of tractography of optic radiation and validation on a lesion model was able to confirm the feasibility of the reconstruction. Among the tested algorithms, the most effective was the "Tensor Line" predicting a risk of quadrantanopia when more than 5% of the trajectories have an intersection with the lesion volume. The second part focused on the cognitive process of language whose translation by cortical stimulation during awake surgery for 7 bilingual patients. Twenty-six interference tasks area were found but none was specific to the translation, which is complex to study. Finally, the prospects for integration of these 2 techniques are discussed through three clinical cases

Can DTI fiber tracking of the optic radiations predict visual deficit after surgery?

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An Open-Label, Analgesic Efficacy and Safety of Pituitary Radiosurgery for Patients With Opioid-Refractory Pain: Study Protocol for a Randomized Controlled Trial

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Unmasking Partial Seizure after Deep Brain Stimulation for ă Treatment-Resistant Depression: A Case Report

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Stereotactic Radiation Therapy for Renal Cell Carcinoma Brain Metastases in the Tyrosine Kinase Inhibitors Era: Outcomes of 120 Patients

International audienceThe objective of the study was to evaluate the outcomes of a large consecutive series of 362 patients with renal cell carcinoma (RCC) brain metastases using stereotactic radiosurgery (SRS) in the tyrosine kinase inhibitor (TKI) era. Sixty-one patients (226 metastases) were treated using Gamma-Knife and 63 patients (136 metas-tases) using linear accelerator. The association of SRS with TKI is highly efficient in brain metastases from RCC and, appears safe and avoids whole-brain radiotherapy. Background: The objective of the study was to evaluate the outcomes in terms of efficacy and safety of a large consecutive series of 362 patients with renal cell carcinoma (RCC) brain metastases treated using stereotactic radi-osurgery (SRS) in the tyrosine kinase inhibitor (TKI) era. Patients and Methods: From 2005 to 2015, 362 consecutive patients with brain metastases from RCC were treated using SRS in 1 fraction: 226 metastases (61 patients) using Gamma-Knife at a median of 18 Gy (50% isodose line); 136 metastases (63 patients) using linear accelerator at a median of 16 Gy (70% isodose line). The median patient age was 58 years. At the first SRS, 37 patients (31%) received a systemic treatment. Among systemic therapies, TKIs were the most common (65%). Results: The local control rates were 94% and 92% at 12 and 36 months, respectively. In multivariate analysis, a minimal dose >17 Gy and concomitant TKI treatment were associated with higher rates of local control. The overall survival rates at 12 and 36 months were 52% and 29%, respectively. In multivariate analysis, factors associated with poor survival included age !65 years, lower score index for SRS, concomitant lung metastases, time between RCC diagnosis and first systemic metastasis 4 months, occurrence during treatment with a systemic therapy, no history of neurosurgery, and persistence or occurrence of neurological symptoms at 3 months after SRS. Seventeen patients had Grade III/IV adverse effects of whom 3 patients presented a symptomatic radionecrosis. Conclusion: SRS is highly effective in patients with brain metastases from RCC. Its association with TKIs does not suggest higher risk of neurologic toxicity