Resection of an Intraventricular Metastatic Tumor with Minimally Invasive Port Technique: 2-Dimensional Operative Video.

The use of minimally invasive port technology has been proposed as a safe method to reduce retractor-induced parenchymal injury, particularly for the resection of deep-seated lesions.1-6 A 69-year-old woman with a history of previous colon cancer surgery presented with gait disturbances and progressive headaches. Magnetic resonance imaging revealed a tumor involving the right ventricular atrium that appeared consistent with metastasis. A parieto-occipital craniotomy was performed on the basis of the preoperatively planned surgical trajectory (Video 1). After the dural incision, the arachnoid was opened down to the sulcus under visualization with microscope. Next, the ViewSite Brain Access system tubular retractor (VBAS; Vycor Medical Inc., Boca Raton, Florida, USA) was introduced toward the lesion under navigation guidance. Once the ventricular atrium was entered, the surface of the tumor came into view. It was coagulated and progressively debulked with ultrasonic aspirator. After the mass was adequately decompressed, a plane of dissection between the ependyma and the tumor could be developed with dynamic angulation of the port in order to allow better visualization. Finally, the tumor could be gently rolled away from the choroid plexus and removed. Meticulous hemostasis was achieved, and the tubular retractor was slowly removed. The patient recovered uneventfully without neurologic deficits on follow-up, and the postoperative magnetic resonance imaging evidenced a complete resection of the tumor. The video illustrates technical nuances and demonstrates the feasibility of minimal access port surgery for the resection of intraventricular lesions with low morbidity and mortality using microsurgical techniques. The patient consented to the publication of her image.

Introducing a Realistic, Low-Cost Simulation Model for Clipping of Brain Aneurysms.

BACKGROUND: The current trend toward endovascular treatment of brain aneurysms may have a negative impact on young neurosurgeons who are less exposed to these lesions, thus affecting the acquisition of surgical skills in the field. Different training models have emerged to help cope with this issue, but these have specific pitfalls. Training models based on live animals or cadaveric specimens face increasing restrictions as regulations become a barrier in accessibility for everyday skills development. We introduce a novel, realistic, and inexpensive simulation model using a fresh bovine brain, and we assess its face and content validity as a training tool. METHODS: A fresh bovine brain is used to simulate microsurgical fissure dissection. Arterial and aneurysmal components are created with arteries and veins harvested from chicken thigh. A 12-item questionnaire using the Likert numeric scale (grades 1 - 5) was used to assess the validity of model in 10 surgeons. RESULTS: Ten neurosurgeons performed the simulated clipping of the aneurysm and completed a questionnaire. All surgeons surveyed responded "agree" or "strongly agree" that the simulator, and the skills trained with it, are comparable to clipping brain aneurysms. All respondents believed that this simulator could improve patient safety. CONCLUSIONS: We present a novel, realistic, and inexpensive simulation model for the clipping of brain aneurysms. This model was partially validated by the opinion of field experts. We believe this model has the potential to become a useful training tool for young neurosurgeons who have little exposure to real aneurysm cases.

Flow recovery after posterior clinoidectomy for surgical clipping of anterior choroidal aneurysm.

Inadvertent flow alterations in the parent artery during microsurgical clipping might produce postoperative ischemic complications. Intraoperative recognition of such alterations and its correction might improve operative outcomes in these patients. We present the case of a thirty-five-year-old male with an incidental small left anterior choroidal aneurysm. Microsurgical clipping induced an external compression of the anterior choroidal artery against the posterior clinoidal process which was identified in situ through surgical exploration and the loss of arterial doppler signal in the vessel. After failed attempts at clip repositioning, a posterior clinoidectomy was performed to decompress the artery. This resulted in arterial flow recovery. The aneurysm was successfully treated, and a severe ischemic complication was likely avoided. This intraoperative phenomenon has not yet been described in the literature.

The Minimally Invasive Posterolateral Transcavernous-Transtentorial Approach. Technical Nuances, Proof of Feasibility, and Surgical Outcomes Throughout a Case Series of Sphenopetroclival Meningiomas.

OBJECTIVE: Sphenopetroclival (SPC) meningiomas are considered among the most complex skull-base neoplasms to approach surgically. We aim to determine whether some SPC meningiomas can be safely and effectively treated using a modified minimally invasive pterional posterolateral transcavernous-transtentorial approach (MIPLATTA). METHODS: Fourteen patients harboring SPC meningiomas were surgically treated through a MIPLATTA. MIPLATTA includes a minipterional craniotomy, anterior extradural clinoidectomy, peeling of the temporal fossa, decompression of cranial nerves (CNs) in the cavernous sinus, and sectioning of the tentorium to reach the upper part of the posterior fossa. RESULTS: Gross total resection was achieved in 11 of 14 patients (78%), whereas near-total resection was accomplished in the other 3 patients (22%), each of whom underwent a further complementary retrosigmoid approach for gross total tumor resection. There were no deaths, and 13 of 14 patients were independent at 6 months follow-up (modified Rankin Scale score ≤2). One patient had pontine infarction after the procedure and experienced moderate disability at follow-up (modified Rankin Scale score 3). All patients had some degree of CN impairment. Of 38 cranial neuropathies, 15 (39%) improved, 20 (53%) remained stable, and 3 (8%) worsened postoperatively. Four new CN deficits were observed postoperatively in 3 patients (fourth CN, 2 patients; third CN, 1; fifth CN, 1). CONCLUSIONS: MIPLATTA is a useful and safe treatment alternative that allows resection of large SPC tumors with dominant invasion of cavernous sinus and middle fossa, preserves hearing and facial motor function, and provides good chances of recovery of visual and oculomotor deficits.

Intra- and extradural anterior clinoidectomy: anatomy review and surgical technique step by step.

PURPOSE: The complex relations of the paraclinoid area make the surgical management of the pathology of this region a challenge. The anterior clinoid process (ACP) is an anatomical landmark that hinders the visualization and manipulation of the surrounding neurovascular structures, hence in certain surgical interventions might be necessary to remove it. We reviewed the anatomical relationships that involve the paraclinoid area and detailed the step-by-step techniques of intra and extradural clinoidectomy in cadaveric specimens. MATERIALS AND METHODS: A literature review was done describing the most relevant anatomic relationships regarding the anterior clinoid process. Extradural and intradural clinoidectomy techniques were performed in six dry bone heads and in ten previously injected cadaverous specimens with colored latex (Sanan et al. in Neurosurgery 45:1267-1274, 1999) and each step of the procedure was recorded using photographic material. Finally, an analysis of the anatomical exposure achieved in each of the techniques used was performed. RESULTS: The main advantage of the intradural clinoidectomy technique is the direct visualization of the neurovascular structures adjacent to the ACP when drilling, at the same time, opening the Sylvian fissure will allow the direct visualization of the ACP variants. The main advantage offered by the extradural technique is that the dura protects adjacent eloquent structures while drilling. Among the disadvantages, it is noted that the same dura that would protect the underlying structures also prevents the direct visualization of these neurovascular structures adjacent to the ACP. CONCLUSION: We reviewed the anatomy of the paraclinoid area and made a step-by-step description of the technique of the anterior clinoidectomy in its intra- and extradural variants in cadaveric preparations for a better understanding.

Microsurgical clipping of multiple cerebral aneurysms in the acute phase of aneurysmal subarachnoid hemorrhage through a minipterional approach: The Chilean experience.

OBJECTIVE: The minipterional craniotomy (MPTc) has been widely accepted as a minimally invasive alternative to the pterional approach for the treatment of certain small non-ruptured anterior circulation aneurysms. The aim of this study was to determine the effectiveness and safety of the MPTc in the context of a complex and potentially harmful scenario: acute onset of subarachnoid hemorrhage (SAH) in patients harboring multiple intracranial aneurysms (MIA). METHODS: Patients harboring MIA clipped through a unilateral MPTc were selected from four retrospective databases of four high-volume neurosurgical centers. Patients with a Hunt & Hess score 4 or 5 were not considered candidates for clipping through a MPTc. Medical records and radiological images were retrospectively reviewed. Epidemiological, clinical and radiological data, as well as short-term outcome (modified Rankin scale at 6 month-follow-up) were analyzed. RESULTS: 16 patients harboring 33 aneurysms (16 ruptured, 17 non ruptured) met the inclusion criteria. Each aneurysm size was 5.7 ± 2.1 mm (range 3-11). 12 out of 33 aneurysms were located in the middle cerebral artery (MCA). Anterior communicating (ACom) and MCA aneurysms were the aneurysm locations most commonly ruptured (5 each, 62 %). Complete occlusion was achieved in 32 aneurysms (97 %) and near-complete occlusion in 1 (3%). 13 patients (93 %) were independent at 6 month-follow-up. Mortality rate was 0%. Complications included 1 cerebrospinal-fluid leakage. CONCLUSION: When indicated (Hunt Hess < 4), performing a MPTc is safe and effective in aSAH cases with multiple aneurysms.

Novel Simulation Model with Pulsatile Flow System for Microvascular Training, Research, and Improving Patient Surgical Outcomes.

BACKGROUND: Simulation allows surgical trainees to acquire surgical skills in a safe environment. With the aim of reducing the use of animal experimentation, different alternative nonliving models have been pursued. However, one of the main disadvantages of these nonliving models has been the absence of arterial flow, pulsation, and the ability to integrate both during a procedure on a blood vessel. In the present report, we have introduced a microvascular surgery simulation training model that uses a fiscally responsible and replicable pulsatile flow system. METHODS: We connected 30 human placentas to a pulsatile flow system and used them to simulate aneurysm clipping and vascular anastomosis. RESULTS: The presence of the pulsatile flow system allowed for the simulation of a hydrodynamic mechanism similar to that found in real life. In the aneurysm simulation, the arterial flow could be evaluated before and after clipping the aneurysm using a Doppler ultrasound system. When practicing anastomosis, the use of the pulsatile flow system allowed us to assess the vascular flow through the anastomosis, with verification using the Doppler ultrasound system. Leaks were manifested as "blood" pulsatile ejections and were more frequent at the beginning of the surgical practice, showing a learning curve. CONCLUSIONS: We have provided a step-by-step guide for the assembly of a replicable and inexpensive pulsatile flow system and its use in placentas for the simulation of, and training in, performing different types of anastomoses and intracranial aneurysms surgery.

Aneurisma gigante de Arteria Cerebral Media: Trapping y By-Pass / Giant Aneurysm of the Middle Cerebral Artery: Trapping and By-Pass

Objetivo: Presentar la resolución quirúrgica de un aneurisma gigante de arteria cerebral media mediante técnica de Trapping y By-Pass. Introducción: La tasa de mortalidad a 5 años de pacientes con aneurismas gigantes es del 80%. Debido a su cuello ancho en ocasiones el clipado directo no es posible, requiriendo realizar Trapping del aneurisma seguido de revascularización mediante By-Pass. Material y Método: Se analizaron datos de historia clínica, imágenes complementarias pre y postquirúrgicas, así como imágenes de video intraoperatorias de un paciente portador de aneurisma gigante de arteria cerebral media intervenido en nuestro centro. Resultados: Mediante abordaje Pterional se localizó arteria temporal superficial y sus ramos. Luego de una cuidadosa disección del saco aneurismático se intentó el clipado primario, debido a su cuello ancho, aterosclerosis asociada y trombo intrasacular, el flujo en la rama temporal de arteria cerebral media era comprometido por el clip. Se decidió la oclusión del aneurisma mediante técnica de trapping y, en mismo tiempo quirúrgico, realización de By Pass extra-intracraneano de arteria temporal superficial a rama temporal de arteria cerebral media. A su vez se secciono el aneurisma y se removió el trombo contenido en su interior, logrando disminuir el efecto de masa ejercido por el mismo. Se corroboro permeabilidad intraquirurgica mediante Doppler y en el postoperatorio alejado mediante angiotomografía con reconstrucción 3D. El paciente evoluciono sin complicaciones asociadas con un Rankin modificado de 1. Conclusión: Se presentó resolución quirúrgica de aneurisma gigante de arteria cerebral media mediante técnica de Trapping seguida de By-Pass extra-intra craneano temporo-silviano

Objective: To present the surgical resolution of a giant aneurysm of the middle cerebral artery using Trapping and By-Pass technique. Introduction: The 5-year mortality rate of patients with giant aneurysms is 80%. Due to its wide neck, sometimes-direct clipping is not possible, requiring trapping of the aneu-rysm followed by bypass revascularization. Material and Method: Clinical history data and intraoperative video images of a pa-tient with a giant aneurysm of the middle cerebral artery were analyzed. Results: The superficial temporal artery and its branches were identified through a Pterional approach. After careful aneurysm dissection, primary clipping was attempted, but the flow in the temporal branch of the middle cerebral artery was compromised. Due to its wide neck, associated atherosclerosis and intrasaccular thrombus, an Extra-intracranial bypass was performed from superficial temporal artery to temporal branch of middle cerebral artery, followed by trapping technique of the aneurysm. Then the aneu-rysm was sectioned and the thrombus contained inside was removed, decreasing the mass effect exerted by it. A Doppler probe was used to corroborate bypass permeability, as well as 3D reconstruction angiotomography during the postoperative period. The pa-tient was discharged without associated complications and a modified Rankin scale of 1. Conclusion: Surgical resolution of a giant middle cerebral artery aneurysm was present-ed by Trapping technique followed by extra-intra-cranial temporo-Silvian bypass

Robot-Assisted Insular Depth Electrode Implantation Through Oblique Trajectories: 3-Dimensional Anatomical Nuances, Technique, Accuracy, and Safety.

BACKGROUND: The insula is a deep cortical structure that has renewed interest in epilepsy investigation. Invasive EEG recordings of this region have been challenging. Robot-assisted stereotactic electroencephalography has improved feasibility and safety of such procedures. OBJECTIVE: To describe technical nuances of three-dimensional (3D) oblique trajectories for insular robot-assisted depth electrode implantation. METHODS: Fifty patients who underwent robot-assisted depth electrode implantation between June 2017 and December 2018 were retrospectively analyzed. Insular electrodes were implanted through oblique, orthogonal, or parasagittal trajectories. Type of trajectories, accuracy, number of contacts within insular cortex, imaging, and complication rates were analyzed. Cadaveric and computerized tomography/magnetic resonance imaging 3D reconstructions were used to visualize insular anatomy and the technical implications of oblique trajectories. RESULTS: Forty-one patients (98 insular electrodes) were included. Thirty (73.2%) patients had unilateral insular coverage. Average insular electrodes per patient was 2.4. The mean number of contacts was 7.1 (SD ± 2.91) for all trajectories and 8.3 (SD ± 1.51) for oblique insular trajectories. The most frequently used was the oblique trajectory (85 electrodes). Mean entry point error was 1.5 mm (0.2-2.8) and target error was 2.4 mm (0.8-4.0), 2.0 mm (1.1-2.9) for anterior oblique and 2.8 mm (0.8-4.9) for posterior oblique trajectories. There were no complications related to insular electrodes. CONCLUSION: Oblique trajectories are the preferred method for insular investigation at our institution, maximizing the number of contacts within insular cortex without traversing through sulci or major CSF fissures. Robot-assisted procedures are safe and efficient. 3D understanding of the insula's unique anatomical features can help the surgeon to improve targeting of this structure.

Technical Description of Minimally Invasive Extradural Anterior Clinoidectomy and Optic Nerve Decompression. Study of Feasibility and Proof of Concept.

BACKGROUND: Several diseases that involve the optic canal or its contained structures may cause visual impairment. Several techniques have been developed to decompress the optic nerve. OBJECTIVE: To describe minimally invasive extradural anterior clinoidectomy (MiniEx) for optic nerve decompression, detail its surgical anatomy, present clinical cases, and established a proof of concept. METHODS: Anatomic dissections were performed in cadaver heads to show the surgical anatomy and to show stepwise the MiniEx approach. In addition, these surgical concepts were applied to decompress the optic nerve in 6 clinical cases. RESULTS: The MiniEx approach allowed the extradural anterior clinoidectomy and a nearly 270° optic nerve decompression using the no-drill technique. In the MiniEx approach, the skin incision, dissection of the temporal muscle, and craniotomy were smaller and provided the same extent of exposure of the optic nerve, anterior clinoid process, and superior orbital fissure as that usually provided by standard techniques. All patients who underwent operation with this technique had improved visual status. CONCLUSIONS: The MiniEx approach is an excellent alternative to traditional approaches for extradural anterior clinoidectomy and optic nerve decompression. It may be used as a part of more complex surgery or as a single surgical procedure.

Abordaje Quirúrgico a la Cisterna Interpeduncular / Surgical Approach to the Interpeduncular Cistern

Objetivo: Describir el acceso quirúrgico a la fosa interpeduncular para la resección de cavernomas ubicados en situación ventromedial del mesencéfalo. Introducción: El abordaje ¨Pretemporal¨ contralateral con resección orbitocigomatica utilizando la via transilviana, permite abordar la cara ventral de la fosa interpeduncular para lesiones comprendidas entre la union diencefalo-mesencefálica y el surco ponto-mesencefálico. Materiales y Métodos: Datos de historia clínica, fotografías y videos obtenidos de un caso quirúrgico operado en nuestro servicio. Disecciones cadavéricas en 14 piezas anatómicas de tronco cerebral (9 siguiendo la técnica de Klingler y 5 piezas sin congelar, de modo comparativo), 23 especímenes inyectados describiendose los corredores quirúrgicos a la región, mas estudios complementarios. Discusión: La bibliografía internacional consultada propone el abordaje orbitocigomatico homolateral para lesiones situadas en la fosa interpeduncular. En nuestro caso elegimos el abordaje ¨Pretemporal¨ con resección orbito-cigomática contralateral dada la localización alta de la lesión y la disposición de su eje mayor (antero-posterior) en sentido opuesto, ofreciendo de este modo un mejor ángulo de ataque por esta vía propuesta. Conclusión: En nuestra experiencia el abordaje ¨Pretemporal¨ contralateral con orbitotomia y en ¨particular¨ la resección cigomática mejoró el ángulo de trabajo, desde inferior a superior y de lateral a medial, para alcanzar de este modo lesiones mesencefálicas ventro-mediales ¨altas¨ en el plano sagital, versus un acceso ¨Orbitocigomatico¨ clásico homolateral.

Utilidad de las Escalas de Gradación en el Tratamiento Quirúrgico de Malformaciones Arteriovenosas Cerebrales / Usefulness of the Gradation Scales in the Surgical Treatment of Cerebral Arteriovenous Malformations

Introducción: Las malformaciones arteriovenosas (MAVs) cerebrales comprenden una compleja patología responsable de hasta el 38% de las hemorragias en pacientes de entre 15-45 años, acarreando cada episodio de sangrado un 25-50% de morbilidad y un 10-20% de mortalidad. La decisión terapéutica en un paciente con una MAV debe tener en cuenta la comparación entre los riesgos propios de la intervención y los de la historia natural de esta enfermedad. Objetivo: Evaluar la utilidad de predecir riesgo quirúrgico de diferentes escalas de gradación de MAV cerebrales según nuestra experiencia en una serie de casos. Material y Métodos: Se realizó un análisis bibliográfico de escalas de gradación de riesgo quirúrgico de MAV cerebrales utilizando como motor de búsqueda Pubmed incluyendo como palabras clave "malformación arteriovenosa cerebral" y "escala de gradación" (brain arteriovenous and malformation grading scale). Se analizaron de forma retrospectiva aquellos pacientes intervenidos quirúrgicamente por MAV en este hospital público, se las clasificó acorde a las escalas analizadas y se compararon los resultados obtenidos con los previstos en ellas. Resultados: Se analizaron 90 pacientes intervenidos quirúrgicamente por MAV, sin tratamiento coadyuvante. De forma retrospectiva se los agrupó acorde a las escalas de Spetzler Martin (SM), Spetzler-Ponce (SP) y suplementaria de Lawton. Las MAV grado 3 se subclasificaron según las escalas de Lawton y de de Oliveira. Considerando buenos resultados aquellos con Rankin modificado (mRs) igual o menor a 2. Con un rango de seguimiento de 12 a 48 meses, encontramos buenos resultados en el 100% de MAV SM grado 1, 91.7% de las grado 2, 80% en grado 3 y 42.9% en grado 4. Utilizando la escala SP, 93.7% de buenos resultados en tipo A, 80% en tipo B y 42.9% en tipo C. Subclasifican-do las MAV SM 3 acorde a las escalas de de Oliveira y Lawton, 84% de buenos resultados en el tipo 3A, 71.3% en las 3B, 92% en MAV tipo 3-, 72.1% en el tipo 3+, 60% en tipo 3. Utilizando la escala suplementaria de Lawton combinada con SM, buen resultado en 100% grados II y III, 85,7% grado IV, 87,6 grado V, 80% grado VI, 75% grado VII y 66,6% grado VIII. Conclusión: Reafirmamos en esta serie, la utilidad de estimar riesgo quirúrgico con las escalas SM, SP, y la subclasificación de las MAV grado 3 propuesta por Lawton. Y principalmente el utilizar la escala suplementaria de Lawton-Young al considerar el tratamiento quirúrgico de los pacientes con MAV que sangraron.

Introduction: Brain arteriovenous malformations (AVM) are a complex disease responsible for up to 38% of hemorrhages in patients between 15-45 years old, carrying every bleeding episode a 25-50% risk of morbidity and a 10-20% of mortality. The therapeutic decision in a patient with an AVM needs to consider both the risks of the intervention and the risks of the natural evolution of the disease. Objective: To assess the effectiveness of different AVM grading scales in predicting surgical risks according to our experience in a case series. Material and Method: a literature review of the AVM grading scales was made, through Pubmed including as key words "brain arteriovenous malformations" and "grading scale". A retrospective analysis was made of patients with AVM who were operated in our institution, they were classified according to the scales and their results were compared. Results: 90 patients were operated in our institution with AVM. Retrospectively, they were classified according to the Spetzler-Martin (SM), Spetzler-Ponce (SP), Lawton supplementary, and the sub-classifications in AVM grade 3, from Lawton and de Oliveira. Good outcome were considered when modified Rankin Scale (mRs) was equal or less than 2. The follow-up ranged from 12-48 months, having good outcome in 100% of AVM SM grade I, 91,7% grade II, 80% in grade III and 42,9% in grade IV. Using the SP scale, 93,7% of good outcome in grade A, 80% in grade B and 42,9% in grade C. In the sub-classification of AVM SM 3, we found 84% of good outcome in type 3A de Oliveira and 71,3% in type 3B. According to the Lawton scale, good outcome were found in 92% in type 3-, 72,1% in type 3+ and 60% in type 3. Using Lawton supplementary scale combined with SM, there were 100% of good outcome in grades II and III, 85,7% in grade IV, 87,6% in grade V, 80% in grade VI, 75% in grade VII, 66,6% in grade VIII. Conclusion: In our series, we reaffirm the effectiveness to predict surgical risk of the following scales: SM, SP and the Lawton's sub-classification of AVM grade 3. Specially, the use of the supplementary Lawton-Young scale in the surgical treatment of bleeding AVMs.

[Usefulness of Gradation Scales in the Surgical Treatment of Cerebral Arteriovenous Malformations]. / Utilidad de las Escalas de Gradación en el Tratamiento Quirúrgico de Malformaciones Arteriovenosas Cerebrales.

INTRODUCTION: Brain arteriovenous malformations (AVM) are a complex disease responsible for up to 38% of hemorrhages in patients between 15-45 years old, carrying every bleeding episode a 25-50% risk of morbidity and a 10-20% of mortality. The therapeutic decision in a patient with an AVM needs to consider both the risks of the intervention and the risks of the natural evolution of the disease. OBJECTIVE: To assess the effectiveness of different AVM grading scales in predicting surgical risks according to our experience in a case serie. MATERIAL AND METHOD: A literature review of the AVM grading scales was made, through Pubmed including as key words "brain arteriovenous malformations" and "grading scale". A retrospective analysis was made of patients with AVM who were operated in our institution, they were classified according to the scales and their results were compared. RESULTS: 90 patients were operated in our institution with AVM. Retrospectively, they were classified according to the Spetzler-Martin (SM), Spetzler-Ponce (SP), Lawton supplementary, and the sub-classifications in AVM grade 3, from Lawton and de Oliveira. Good outcome were considered when modified Rankin Scale (mRs) was equal or less than 2. The follow-up ranged from 12-48 months, having good outcome in 100% of AVM SM grade I, 91,7% grade II, 80% in grade III and 42,9% in grade IV. Using the SP scale, 93,7% of good outcome in grade A, 80% in grade B and 42,9% in grade C. In the sub-classification of AVM SM 3, we found 84% of good outcome in type 3A de Oliveira and 71,3% in type 3B. According to the Lawton scale, good outcome were found in 92% in type 3-, 72,1% in type 3+ and 60% in type 3. Using Lawton supplementary scale combined with SM, there were 100% of good outcome in grades II and III, 85,7% in grade IV, 87,6% in grade V, 80% in grade VI, 75% in grade VII, 66,6% in grade VIII. CONCLUSION: In our serie, we reaffirm the effectiveness to predict surgical risk of the following scales: SM, SP and the Lawton's sub-classification of AVM grade 3. Specially, the use of the supplementary Lawton-Young scale in the surgical treatment of bleeding AVMs.

[Foreign accent syndrome after aneurysmal disappearance due to AVM treatment]. / Remisión de aneurisma luego de exéresis de MAV con aparición de síndrome del acento extranjero.

INTRODUCTION: Aneurysms associated with arteriovenous malformations (AVM) are vascular lesions are usually found in up to 15% of cases, increasing the overall risk of bleeding. The behavior against associated aneurysms is dichotomous while there are reports of disappearance of the same after the removal of the AVM; other items emphasize early treatment. Foreign accent syndrome is a rare neurological disorder in which the patient speaks his mother language as would a foreigner and sounds as foreign "accent" to native listeners. OBJECTIVE: To report a patient who developed foreign accent syndrome after excision of an AVM and the evolution of an associated aneurysm. CASE PRESENTATION: A pediatric patient after a resection of fronto-opercular AVM referred back completely on an aneurysm associated hyper flow, presented with postsurgical foreign accent syndrome. CONCLUSION: A rare syndrome and spontaneous resolution of a proximal aneurysm after excision of an AVM is hereby reported.

Remisión de aneurisma luego de exéresis de MAV con aparición de síndrome del acento extranjero / Aneurysm remission after MAV surgery with appearance of foreign accent syndrome

Introducción: Los aneurismas asociados a malformaciones arteriovenosas (MAV) son lesiones vasculares que suelen encontrarse hasta en el 15% de los casos, incrementando el riesgo global de hemorragia. La conducta frente a los aneurismas asociados es dicotómica en la literatura, mientras existen reportes de la desaparición de los mismos luego de la exéresis de la MAV, otros artículos enfatizan su tratamiento precoz. El síndrome del acento extranjero es un raro trastorno neurológico en el que el paciente habla su lengua materna como lo haría una persona extranjera y suena con “acento” extranjero a oídos de los oyentes nativos. Objetivo: Presentar un paciente que desarrolla el síndrome del acento extranjero posterior a la exéresis de una MAV y la evolución de un aneurisma asociado. Presentación de caso: Paciente pediátrico que luego de la exéresis de una MAV fronto-opercular posterior izquierda remite por completo un aneurisma de hiperflujo asociado, presentando en el postquirúrgico el síndrome del acento extranjero.Conclusión: Queda reportado el caso de este raro síndrome y la resolución espontánea de un aneurisma proximal luego de la exéresis de una MAV.

Introduction: The aneurysms associated with arteriovenous malformations (AVM) are vascular lesions that are usually found in up to 15% of cases, increasing the overall risk of bleeding. The behavior against associated aneurysms is dichotomous while there are reports of the disappearance of the same after the removal of the AVM, other items emphasize early treatment. Foreign accent syndrome is a rare neurological disorder in which the patient speaks his mother language as you would a foreigner and sounds with foreign "accent" to native listeners.Objective: To report a patient who developed foreign accent syndrome after excision of an AVM and the evolution of an associated aneurysm.Case presentation: pediatric patient that after a resection of fronto-opercular AVM refers back completely on an aneurysm associated hyper flow, presenting postsurgical foreign accent syndrome.Conclusion: the case of this rare syndrome and spontaneous resolution of a proximal aneurysm after excision of an AVM is hereby reported.

Giant Pseudoaneurysm as a delayed Surgical Complication in a Patient Operated on a Giant Neuroma of the Vagus Nerve: Case Report and Management Considerations / Pseudoaneurisma gigante como complicação cirúrgica em paciente operado com neuroma gigante do nervo vago: relato de caso e considerações

The vertebral artery has four segments. The horizontal portion of the V3 segment is the most exposed portion of the vertebral artery to potential iatrogenic injuries during surgical approaches to the posterior fossa.We present an unusual case of a patient who was operated on a giant neuroma of the left vagus nerve, with incidental vertebral artery iatrogenic injury, the development of a delayed giant pseudoaneurysm, and the treatment for this complication. We conclude that endovascular treatment may be a good option for the management of this serious surgical complication.

A artéria vertebral tem quarto segmentos. A porção horizontal do segmento V3 é a mais exposta a potenciais lesões iatrogênicas durante procedimento cirúrgico de acesso à fossa posterior. Apresentamos caso incomum de paciente submetido à cirurgia para neuroma gigante no nervo vago esquerdo, com acidental lesão da artéria vertebral iatrogênica, desenvolvimento de posterior pseudoaneurisma gigante e tratamento para esta complicação. Concluímos que o tratamento endovascular pode ser uma boa opção para o cuidado desta grave complicação cirúrgica.

Mapeo del lenguaje utilizando estimulación magnética transcraneal repetitiva por navegación: un estudio comparativo con la estimulación cortical directa intraoperatoria / Language mapping using repetitive transcranial magnetic stimulation by navigation: a comparative study with direct intraoperative cortical stimulation

Introducción: la estimulación cortical directa (DCS) es una metodología corrientemente usada para localizar áreas del lenguaje en intervenciones quirúrgicas que incluyan resecciones.La estimulación magnética transcraneana repetitiva (rTMS) a demostrado también su capacidad para inducir alteraciones transitorias. Recientemente el desarrollo del Sistema de Navegación de TMS asegura precisa localización del sitio estimulado. El objetivo del trabajo es estudiar la confiabilidad de la estimulación magnética transcraneal repetitiva navegada (nrTMS) en la localización de los sitios del lenguaje. Métodos: Once pacientes seleccionados para mapeo del lenguaje por DCS fueron evaluados pre-cirugía con nrTMS. Los mapeos de lenguaje prequirúrgicos mediante nrTMS fueron comparados con DCS. Resultados: Un total de 25 nrTMS sitios del lenguaje y 38 DCS fueron localizados. La sensibilidad y la especificidad obtenida fue de 88.4 y 95.6, respectivamente. La distancia media fue evaluada en 4,5mm. Conclusiones: Los dispositivos de nrTMS permiten la identificación de las áreas corticales del lenguaje. Con un alto grado de concordancia con el mapeo TMS. La nrTMS se muestra como una herramienta de interés en la investigación y aplicación práctica en la función del lenguaje.

Introduction: direct cortical stimulation (DCS) is currently used to localise language areas in surgical resections. Repetitive transcranial magnetic stimulation (rTMS) has also shown its capacity to induce transient language alterations. Newly developed Navigated Brain Systems of TMS ensure precise topographical localisation of the stimulated site. The objective was to study the reliability of navigated repetitive transcranial magnetic stimulation (nrTMS) in language sites localisation.Methods: Eleven patients selected for DCS language mapping were presurgically evaluated with nrTMS. These presurgicalnrTMS language maps were then compared with DCS.Results: A total number of 25 nrTMS and 38 DCS language sites were localised. Sensitivity and specificity were calculated as 88.4 and 95.6 respectively. Mean distance was assessed as 4.5 millimetres. Conclusions: nrTMS devices allow identification of cortical language areas, with a high degree of concordance to TMS mapping. NrTMS shows up as an interesting tool for research and practical application in language function.

Unusual case of isolated frontal sinus mycosis after several years of frontal sinus fracture: case report / Caso incomum de micose isolada do seio frontal depois de vários anos da fratura do seio frontal: relato de caso

Fractures of the frontal sinus account for 5 to 12% of all the maxillofacial fractures. There are different complications related to frontal sinus fractures and some of them may develop even years after the traumatic episode. Isolated fungal infection of the frontal sinus is very exceptional. The most commonly affected paranasal sinus by fungal infection is maxillary sinus. We present an unusual case of isolated fungal infection of the frontal sinus on an immunocompetent patient who had an old frontal sinus fracture that had happened 70 years before. To the best of our knowledge, this is the first reported case in which these particular circumstances coexist.

As fraturas do seio frontal correspondem a 5 a 12% das fraturas maxilofaciais. Há diferentes complicações relacionadas às fraturas do seio frontal, e algumas delas podem se desenvolver depois de anos do trauma. A infecção fúngica do seio frontal é bastante incomum. O seio paranasal mais comumente afetado por infecções fúngicas é o seio maxilar. Apresentamos um caso incomum de infecção fúngica isolada no seio frontal de um paciente imunocompetente com uma antiga fratura do seio, ocorrida 70 anos antes. Até onde sabemos, este é o primeiro caso relatado da coexistência dessas duas circunstâncias particulares.

Selección del lado de abordaje a los aneurismas de la arteria comunicante anterior / Selection of the approach side to the aneurysms of the anterior communicating artery

Objetivo: analizar el lado de abordaje pterional elegido teniendo en cuenta la disposición del segmento postcomunicante de las arterias cerebrales anteriores (A2) en el plano coronal y sus implicancias quirúrgicas. Material y Método: Estudio observacional descriptivo retrospectivo. Se analizaron 24 pacientes con aneurismas de la arteria comunicante anterior de variedad superior y antero-superior, operados en el período 2009-2014. Se operaron 22 pacientes con Hemorragia Subaracnoidea (91.67%) y 2 pacientes con aneurismas incidentales (8.33%). Se estudió la dominancia del segmento precomunicante (A1), la variedad de A2 (abierta o cerrada) y sus consecuencias quirúrgicas: necesidad de aspiración del girus recto (AGR), utilización de clip fenestrados, presencia de contusión debido a retracción cerebral, isquemia en territorio de perforantes (ITP) y cuello remanente. Resultados: De los 24 pacientes estudiados, 12 (50%) presentaban una variedad A2 abierta. Tan solo 1 requirió AGR, 1 sufrió ITP y 2 contusiones, sin necesidad de utilizar clips fenestrados ni tampoco registrarse algún cuello remanente. Los 12 pacientes restantes (50%) presentaron una variedad A2 cerrada. En este grupo fue necesario AGR en 8 casos, utilización de clip fenestrados en 3 casos, se registraron 3 ITP, 3 contusiones y 1 con cuello remanente (p=0.01). Conclusión: Creemos que abordar a los aneurismas de variedad superior y antero-superior del lado en el que las A2 representan una variedad abierta, permite lograr una correcta exposición anatómica con el consiguiente clipado aneurismático adecuado y reducción de las complicaciones quirúrgicas.

Objective: to analyze the chosen side in a pterional approach based on the position of the postcommunicating segment of anterior cerebral artery (A2) in a coronal plane, and its surgical requirements and complications. Material and Method: A descriptive observational retrospective study has been designed. We analyzed 24 patients with anterior communicating artery aneurysms projecting superior and supero-anterior, who underwent microsurgical clipping between 2009-2014. This study includes 22 subarachnoid hemorrhages (91.67%) and 2 incidental aneurysms (8.33%). We studied the dominancy of the precommunicating segment (A1), A2 plane (open or closed) and the surgical requirements: gyrus rectus aspiration (GRA) or the need of fenestrated clips, and complications: cerebral contusion due to brain retraction, perforators' ischemia (PI) and residual neck. Results: Out of the 24 patients, 12 (50%) were A2 open plane. Only 1 required GRA, 1 suffered perforators' ischemia and 2 had cerebral contusion. No fenestrated clip was used, and there was no residual neck. The remaining 12 patients (50%) had an A2 close plane. In this group, GRA was necessary in 8 cases and the use of fenestrated clip in 3. Perforators' ischemia was present in 3 cases, whereas another 3 patients suffered cerebral contusion and 1 had a residual neck (p=0.01). Conclusion: We suggest that approaching anterior cerebral arteries aneurysms projecting superior and supero-anterior from an A2 open plane, allows an optimal anatomical exposure view with an adequate aneurysm clipping and reducing surgical complications.