Intracanalicular vestibular schwannomas: facial and hearing outcomes according to the location of the tumor in relation to the nerves of the internal auditory canal.

OBJECTIVE: The objective was to evaluate whether the position of the nerves within the internal auditory canal (IAC) has any effect on preoperative and postoperative cochlear and facial nerve function in patients with intracanalicular vestibular schwannoma (VS) resected through the retrosigmoid transmeatal approach. METHODS: Forty-four patients with sporadic intracanalicular VS, from a series of 710 patients with VS who underwent operations from January 1993 to April 2022, were retrospectively reviewed. The pattern of displacement of the cranial nerves and tumor within the IAC was recorded. Tumors were divided into 2 types: type T1A lesions had only anteriorly displaced nerves, and type T1B had posteriorly displaced vestibular nerves and anteriorly displaced facial and cochlear nerves. Differences in surgical outcomes between groups in terms of facial nerve function and hearing preservation were evaluated. RESULTS: Thirty-five cases (79.5%) were T1A tumors and 9 were T1B (20.5%). Gross-total resection and anatomical preservation of the facial and cochlear nerves were achieved in all patients. Postoperatively, all patients with T1A VS maintained normal facial nerve function; however, among T1B VS patients, 6 (67%) retained House-Brackmann grade I, 2 worsened to grade II, and 1 worsened to grade III at 6 months (p = 0.006). The 27 T1A VS patients with serviceable hearing maintained this status, and an additional patient with nonserviceable hearing improved to serviceable hearing; among T1B VS patients, only 2 of the 5 patients with serviceable hearing remained as such, 2 evolved to nonserviceable hearing, and 1 lost hearing after surgery (p = 0.0022). T1B VS patients had a 24-fold risk of facial nerve deterioration (relative risk [RR] 25.2, 95% CI 1.42-448.57, p = 0.028) and a 32-fold risk of hearing deterioration (RR 32.7, 95% CI 1.93-553, p = 0.016) after surgery. CONCLUSIONS: In intracanalicular VS, postoperative cochlear and facial nerve function are directly related to the location of the tumor in relation to the nerves, with worse outcomes in cases where the tumor is located between the vestibular and facial-cochlear nerves.

Retrosigmoid Craniotomy and Intradural Variations: Role of Patient-Specific Preoperative Imaging to Identify Landmarks and Relevant Structures.

OBJECTIVE: There are several landmarks to safely identify the limits of the retrosigmoid approach and its intradural variations; however, there has been little discussion about how those landmarks may vary among patients. METHODS: Patient positions; surface landmarks for the retrosigmoid craniotomy; and structures to recognize for transmeatal, suprameatal, suprajugular, and transtentorial extensions were reviewed. RESULTS: The position of the dural sinuses in relation to the zygomatic-inion line and digastric notch line is readily identified on magnetic resonance imaging. For transmeatal drilling, the position of the semicircular canals, vestibular aqueduct, and jugular bulb is best evaluated on computed tomography. For suprameatal drilling, the labyrinth and the position and integrity of the carotid canal are relevant for planning the anterior extension of the approach. For transtentorial extension, it is desirable to identify incisural structures. For suprajugular drilling, the position of the jugular bulb, invasion of venous structures, and integrity of the roof of the jugular foramen must be checked preoperatively. CONCLUSIONS: The retrosigmoid approach is the workhorse of posterior skull base surgery. By recognizing patient-specific variations in known landmarks, the approach may be tailored prevent complications.

Retrosigmoid Infralabyrinthine (Suprajugular) Approach to the Jugular Foramen: Indications, Limitations, and Surgical Nuances.

BACKGROUND: Among the several approaches described to the jugular foramen (JF), the retrosigmoid infralabyrinthine (suprajugular) approach was one of the most recently described. OBJECTIVE: To describe the indications, limitations, and operative nuances of the suprajugular approach. METHODS: We provided a pertinent review of the anatomy, indications, preoperative evaluation, surgical steps and nuances, and postoperative management. RESULTS: The suprajugular approach is suitable for tumors occupying the intracranial compartment with limited extension into the JF. Volume, width, and configuration of the foramen dictate the feasibility of the approach. Tumors invading the venous system are not suitable for this approach. Preoperative 3-dimensional MRI and computed tomography are used to evaluate intrajugular extension, relationship between the tumor and the jugular bulb (JB), venous system invasion, and shape of the JF. During surgery, exposition of the entire posterior border of the sigmoid sinus is needed and removing the bone over the JB. After identification of the JF, the jugular notch and intrajugular process of the roof of the foramen are removed and intrajugular resection is completed. In cases of high-riding JB, it may be gently pushed down to allow visualization of the anterior foramen. In cases of JB laceration, it may be repaired using a muscle patch and usually does preclude further resection. CONCLUSION: The suprajugular approach is variation of the retrosigmoid approach that, when properly indicated, provides excellent exposure of the medial JF, with most anatomical variations and intraoperative complications predicted by a comprehensive preoperative evaluation.

Extending the Indications of 5-Aminolevulinic Acid for Fluorescence-Guided Surgery for Different Central Nervous System Tumors: A Series of 255 Cases in Latin America

Introduction Fluorescence guidance with 5-aminolevulinic acid (5-ALA) is a safe and reliable tool in total gross resection of intracranial tumors, especially malignant gliomas and cases of metastasis. In the present retrospective study, we have analyzed 5-ALA-induced fluorescence findings in different central nervous system (CNS) lesions to expand the indications of its use in differential diagnoses. Objectives To describe the indications and results of 5-ALA fluorescence in a series of 255 cases. Methods In 255 consecutive cases, we recorded age, gender, intraoperative 5-ALA fluorescence tumor response, and 5-ALA postresection status, as well the complications related to the method. Postresection was classified as '5-ALA free' or '5-ALA residual'. The diagnosis of histopathological tumor was established according to the current classification of the World Health Organization (WHO). Results There were 195 (76.4%) 5-ALA positive cases, 124 (63.5%) of whom underwent the '5-ALA free' resection. The findings in the positive cases were: 135 gliomas of all grades; 19 meningiomas; 4 hemangioblastomas; 1 solitary fibrous tumor; 27 metastases; 2 diffuse large B cell lymphomas; 2 cases of radionecrosis; 1 inflammatory disease; 2 cases of gliosis; 1 cysticercosis; and 1 immunoglobulin G4-related disease.

Modified Craniocervical Approach for Resection of the Styloid Process in Patients with Eagle's Syndrome.

Objective Surgical treatment of Eagle's syndrome remains the mainstay of treatment. Palsy of the marginal mandibular branch of the facial nerve is the most significant complication encountered in transcervical resections, due to direct compression during the approach. We proposed a modification of the craniocervical approach to the jugular foramen to resect the styloid process avoiding the marginal mandibular branch and subsequent palsy. Design This is a single-center retrospective cohort study. Setting The research was conducted at a tertiary medical center. Participants From November 2008 to October 2018, 12 patients with Eagle's syndrome underwent treatment using our modified approach. Main Outcome Measures Demographic data, type of Eagle's syndrome, symptomatic side, size of the styloid process, clinical outcomes, and complications were analyzed. Results Mean size of the styloid processes was of 3.34 cm on the operated side (2.3-4.7 cm) and 2.98 cm on the other (2-4.2 cm). Intraoperative facial nerve irritation occurred in one case. Resection of the entire styloid process was achieved in all cases. Eight cases experienced complete improvement, three cases had a partial response, and one case failed to improve. There were no cases of recurrence. Two patients presented transient postoperative auricular paresthesia. There were no cases of mandibular branch palsy, nor any other complications in our series. Conclusions Our modified transcervical approach is effective in avoiding the marginal mandibular branch of the facial nerve, avoiding postoperative palsy.

5-aminolevulinic Acid and Surgical Margin Analysis in Calvarial Metastasis with Pericranium or Dural Extension: Technical Note

Metastasis to the calvarium with direct pericranium or dural infiltration may be treated with radical surgical removal in selected cases. We describe microsurgical resection of calvarial metastases with fluorescence-guided technique using 5-aminolevulinic acid (5-ALA) in two female patients with breast cancer. Fluorescence findings were positive in both cases. Margins in the scalp and dural layer were 5-ALA negative at the end of surgical removal. Intraoperative pathology was performed in all cases to confirm if oncological limits were free of disease. One case was 5-ALA positive in the outer layer of the dura-mater and another in the pericranium. At the end of the removal in both cases, the surgicalmargins were 5-ALA fluorescence-free. Intraoperative pathology confirmed oncological limits of the resection. 5-aminolevulinic acid fluorescence-guided surgery for calvarial metastases with pericranium and/or dural extension seems to be a safe and reliable method to aid the surgical margins for complete removal, possibly delaying or avoiding adjuvant irradiation for progression control.

Microsurgical Anatomy of the Jugular Foramen Applied to Surgery of Glomus Jugulare via Craniocervical Approach.

The jugular foramen remains one of the most complex regions of the human body. Approaching lesions in this area requires extensive anatomical knowledge and experience, due to the many critical neurovascular structures passing through or around the jugular foramen. Here, we present a concise review of the microsurgical anatomy of the jugular foramen in relation to the craniocervical approach.

Gamma knife radiosurgery for trigeminal neuralgia: first case series from Latin America.

INTRODUCTION: Gamma Knife® radiosurgery (GKRS) for trigeminal neuralgia is an effective treatment with at least a 50% reduction of pain in 75-95% of patients. OBJECTIVE: To present the first series of patients treated for trigeminal neuralgia using GKRS in Latin America. METHODS: Retrospective analysis. Analysis consisted of time to improvement of symptoms, best Barrow Neurological Institute scale (BNI) score after procedure, time without pain, time to recurrence and post-procedural hypoesthesia. RESULTS: Nineteen cases of classical trigeminal neuralgia were analyzed and three cases of symptomatic trigeminal neuralgia were described. Mean time from symptom onset to radiosurgery was 99.6 months, and 78.9% of patients had undergone invasive procedures before treatment. Patients were followed for a mean of 21.7 months. BNI I was achieved in 36.8%, IIIa in 21.1%, IIIb in 21.1%, IV in 5.3% and V in 15.7%. New hypoesthesia developed in 12.1% patients, which was associated with achieving BNI I after the procedure (p < 0.05). Time from diagnosis to GKRS was higher in patients who failed to achieve BNI I (143 vs. 76 months). The distance from the root entry zone in patients who achieved BNI I was greater than patients who did not (1.94 vs. 1.14 mm). Mean distance from the root entry zone in patients with new hypoesthesia was 2.85 mm vs. 1.06 mm (p = 0.06). CONCLUSION: Clinical response to GKRS is related to the time between diagnosis and procedure, thus its indication should be considered early in the management of these patients.

Retrosigmoid Transmeatal Approach with 360-Degree Drilling of the Internal Auditory Canal for the Resection of Intracanalicular Meningioma.

Introduction Vestibular schwannomas are the most common lesions occupying the internal auditory canal (IAC); however, almost in 4 to 5% of meningiomas, metastases, cysts, lipomas, and cavernous malformations have been found in this location, mimicking schwannomas. Even though cerebellopontine angle (CPA) meningiomas with the involvement of the IAC are frequently encountered, the presence of a primary intracanalicular meningioma is rare. Objective To show the technical nuances of the retrosigmoid-transmeatal approach to successfully achieve gross total resection (GTR) with preservation of facial and auditory function. Case Report We present a left intracanalicular meningioma on a 60-year-old man with history of tinnitus and hearing loss. Magnetic resonance imaging (MRI) showed a left intracanalicular lesion completely obliterating the IAC and with minor extension to the CPA cistern, with the vestibulocochlear complex dislocated posteriorly, initially diagnosed as a Hannover's T2 vestibular schwannoma. The patient underwent a left retrosigmoid approach, and during the exposure of the lesion, the diagnosis of a meningioma became evident. The transmeatal phase of the approach was modified with a wide opening of the canal, including the anterior wall. Closure was performed using a muscle graft, duramater flap, and fibrin glue. Results GTR was achieved and the patient developed a mild facial palsy (House-Brackmann grade III) which completely recovered within 3 months. Conclusions The retrosigmoid transmeatal approach is suitable to achieve GTR in intracanalicular meningiomas. Some modifications of the approach intended for vestibular schwannomas are necessary and may be performed during the procedure. The link to the video can be found at: https://youtu.be/A9OXRFIl1e8 .

Gamma knife radiosurgery for trigeminal neuralgia: first case series from Latin America / Radiocirurgia por gamma knife para tratamento da neuralgia do trigêmeo: primeira série de casos na América Latina

ABSTRACT Gamma Knife® radiosurgery (GKRS) for trigeminal neuralgia is an effective treatment with at least a 50% reduction of pain in 75-95% of patients. Objective: To present the first series of patients treated for trigeminal neuralgia using GKRS in Latin America. Methods: Retrospective analysis. Analysis consisted of time to improvement of symptoms, best Barrow Neurological Institute scale (BNI) score after procedure, time without pain, time to recurrence and post-procedural hypoesthesia. Results: Nineteen cases of classical trigeminal neuralgia were analyzed and three cases of symptomatic trigeminal neuralgia were described. Mean time from symptom onset to radiosurgery was 99.6 months, and 78.9% of patients had undergone invasive procedures before treatment. Patients were followed for a mean of 21.7 months. BNI I was achieved in 36.8%, IIIa in 21.1%, IIIb in 21.1%, IV in 5.3% and V in 15.7%. New hypoesthesia developed in 12.1% patients, which was associated with achieving BNI I after the procedure (p < 0.05). Time from diagnosis to GKRS was higher in patients who failed to achieve BNI I (143 vs. 76 months). The distance from the root entry zone in patients who achieved BNI I was greater than patients who did not (1.94 vs. 1.14 mm). Mean distance from the root entry zone in patients with new hypoesthesia was 2.85 mm vs. 1.06 mm (p = 0.06). Conclusion: Clinical response to GKRS is related to the time between diagnosis and procedure, thus its indication should be considered early in the management of these patients.

RESUMO A radiocirurgia por Gamma Knife (GKRS) para neuralgia do trigêmeo é um tratamento comprovado, com redução de pelo menos 50% da dor em 75-95% dos casos. Objetivo: Apresentar a primeira série de pacientes tratados por neuralgia do trigêmeo com GKRS na America Latina. Métodos: Análise retrospectiva. A análise consistiu no tempo até melhora do sintoma, melhor escala do Barrow Neurological Institute (BNI) depois do procedimento, tempo sem dor, tempo até recorrência e hipoestesia pós-procedimento. Resultados: Dezenove casos de neuralgia do trigêmeo clássica foram analisados e três casos de neuralgia do trigêmeo sintomática foram descritos. Tempo médio entre começo dos sintomas e GKRS foi de 99,6 meses e 78,9% dos pacientes já tinham sido submetidos a procedimento invasivo prévio. O tempo de acompanhamento médio foi de 21,7 meses. BNI I foi conseguido em 36,8%, IIIa em 21,1%, IIIb em 21,1%, IV em 5,3% e V em 15,7%. Nova hipoestesia apareceu em 12,1% dos casos, o que foi associado a conseguir BNI I pós-procedimento (p < 0,05). Tempo desde o diagnóstico até GKRS foi maior em pacientes que não conseguiram BNI I (143 vs. 76 meses). Distância da zona de entrada do nervo em pacientes que conseguiram BNI I foi maior (1,94 vs. 1,14mm). Distância do zona de entrada do nervo em pacientes com nova hipoestesia foi de 2,85mm vs. 1,06mm (p = 0,06) Conclusão: A resposta à GKRS está relacionada ao tempo entre diagnóstico e procedimento, pelo que a indicação de GKRS deve ser considerada cedo no tratamento desses pacientes.

Indications of 5-Aminolevulinic Acid and Intraoperative MRI in Glioma Surgery: First Cases in Latin America in a Single Reference Center

Introduction The improvement on the extent of resection (EOR) of gliomas with the combination of 5-aminolevulinic acid (5-ALA) and intraoperative magnetic resonance imaging (iMRI) has been demonstrated in previous studies. We present our results with the combined use of 5-ALA and (iMRI) in the surgery of glial lesions. Methods A total of 64 cases of patients with intracranial gliomas who underwent image-guided surgery using 5-ALA with and without (iMRI) were reviewed. All patients underwent an early postoperative MRI to evaluate the EOR. Other intra-operative techniques (awake surgery, electrophysiological stimulation and monitoring) were also performed according to the location of the tumor. Results A total of 18 tumors did not show intraoperative 5-ALA fluorescence (according to the World Health Organization [WHO] classification of tumors, 2 WHO-grade I, 14 WHOgrade II, 1 WHO-grade III and 1 WHO-grade IV), and 46 tumors showed intraoperative 5-ALA fluorescence (3 WHO-grade II, 3 WHO-grade III, 40 WHO-grade IV). In 28 of the 46 5-ALA positive cases, a safe 5-ALA free resection was achieved. In the 5-ALA negative cases, the (iMRI) findings guided the EOR, and complete resection was achieved in 11 cases. Complete resection was opted out in gliomas infiltrating eloquent areas. Conclusions The combined use of 5-ALA and IMRI showed improved results in glioma surgery, offering the safest maximal EOR. In the 5-ALA positive cases (mostly highgrade), fluorescence was a more useful tool. In the 5- ALA negative cases (mostly lowgrade), the (iMRI) was decisive to guide the EOR of the tumor.

Introdução Em estudos anteriores, foi demonstrado um aperfeiçoamento na extensão da resecção (EDR) de gliomas com a combinação de ácido 5-aminolevulínico (5-ALA) e a imagem de ressonância magnética intraoperatória (iRM). Nossos resultados são apresentados com o uso combinado de 5-ALA e (iRM) para a cirurgia de lesões gliais. Métodos Foram revisados 64 casos de gliomas intracranianos submetidos a cirurgia guiada por imagem por meio do uso de 5-ALA, com ou sem RMI. Todos os pacientes foram submetidos a ressonância magnética (RM) pré-operatória para a avaliação da EDR do tumor. Outras técnicas intraoperatórias (cirurgia acordado, estimulação eletrofisiológica e monitoração) também foram realizadas segundo a localização do tumor. Resultados Um total de 18 tumores não apresentaram fluorescência com o 5-ALA (segundo a classificação de tumores da Organização Mundial de Saúde [OMS], 2 com grau OMS I, 14 com grau II, 1 com grau III e 1 com grau IV) e 46 tumores foram fluorescentes (3 com grau II, 3 com grau III, 40 com grau IV). Dos 46 casos positivos para 5-ALA, em 28 foi obtida uma ressecção segura e livre. Nos casos negativos para 5-ALA, os achados da (iRM) orientaram a EDR, e alcançou-se ressecção total em 11 casos. A ressecção total foi descartada em gliomas com infiltração em áreas eloquentes. Conclusões O uso combinado de 5-ALA e (iRM) mostrou melhores resultados na cirurgia de gliomas, oferecendo uma EDR de segurança máxima. Nos casos positivos para 5-ALA (a maioria de grau alto), a fluorescência mostrou-se um instrumento mais útil. Nos casos negativos para 5-ALA (a maioria de grau baixo), a RMI foi decisiva para orientar a EDR tumoral.

Non-schwannomatosis lesions of the internal acoustic meatus-a diagnostic challenge and management: a series report of nine cases.

Vestibular schwannomas (VS) are the most common lesions of cerebellopontine angle (CPA) corresponding to 76-91 % of the cases. Usually, these lesions present typical CT and MRI findings. Non-schwannomatous tumors restricted to the internal auditory meatus (IAM) are rare and their preoperative radiological diagnosis may be difficult. This article describes nine surgically treated intrameatal non-schwannomatous lesions (NSL) and reviews the literature. In the last 16 years, a total of 471 patients with diagnosis of VS were operated on in our department. Preoperatively, 42 patients had diagnosis of intrameatal schwannomas, but surgery revealed in nine cases NSL (3 meningiomas, 3 arachnoiditis/neuritis, 1 cavernoma, 1 vascular loop, and 1 arachnoid cyst). Most frequent symptoms presented by patients with NSL were hearing loss 89 % (8/9) of patients, tinnitus 78 % (7/9), and vertigo 33 % (3/9). Almost all lesions (8/9) presented MRI findings of isointense signal in T1W with contrast enhancement. The only exception was the arachnoid cyst with intracystic bleeding, which was hyperintense in T1W that is not enhanced with contrast. This series shows an occurrence of 21.4 % of non-schwannomatous tumors in 42 cases of lesions restricted to the IAM. Whenever a solely intrameatal enhanced tumor is detected, it is necessary to think about other diagnostic possibilities rather than VS. Therapeutic management may be changed, specially if radiosurgical treatment is considered.

Características de imagens de ressonância magnética intraoperatória da celulose regenerada oxidada absorvível durante cirurgia para gliomas cerebrais / Intraoperative MRI Features of Absorbable Oxidized Regenerated Cellulose During Cerebral Glioma Surgery

Objetivos: Agentes hemostáticos podem apresentar imagens que podem ser confundidas com tumor cerebral residual/recorrente ou abscesso cerebral em exames de ressonância magnética (RM). As características de RM intraoperatória desses agentes não foram ainda descritas na literatura. Este estudo descreve os aspectos de RM intraoperatória da celulose regenerada oxidada absorvível em cirurgias de gliomas cerebrais.Métodos: 72 pacientes com gliomas cerebrais foram examinados com RM intraoperatória de alto campo (1,5T). 32 apresentavam gliomas de baixo grau e 40 de alto grau. Após ressecção da lesão o leito tumoral foi revestido com o agente hemostático.Resultados: Celulose regenerada oxidada absorvível apresentou sinal hiperintenso na sequência T1 em todos os pacientes o que ajudou na identificação de tumor residual sob o plano do agente hemostático.Conclusões: Na seqüência T1 da RM intraoperatória a celulose regenerada oxidada absorvível apresenta sinal hiperintenso que pode ser um marcador útil para delimitar os bordos de resecção tumoral.

Uso estendido de temozolomida em pacientes com glioblastoma: experiência de uma instituição / The prolonged use of temozolomide in glioblastoma patients: a single institution experience

Protocolo de temozolomida (TMZ) publicado em 2005 mostrou aumento importante da sobrevida dos pacientes com glioblastomamultiforme (GBM). Foi definido um protocolo de 6 meses, mas atualmente, diversos centros especializados utilizam protocolosmais longos, chegando a até 3 anos de terapia contínua. O objetivo deste estudo foi comparar a duração do tratamento nosgrupos de pacientes e avaliar a sobrevida destes grupos. Foram avaliados 54 pacientes com diagnóstico de GBM operados entre2004 e 2009. Os dados foram analisados utilizando-se curvas de Kaplan-Meier, teste ANOVA, regressão logística multivariadae teste de correlação de Pearson. Foram consideradas as variáveis idade, gênero, Escala de Performance de Karnosfsky (KPS)no diagnóstico, lado e localização da lesão, grau de ressecção cirúrgica, tempo de uso de TMZ até recorrência, sobrevidalivre de progressão, KPS na recorrência e sobrevida total. De acordo com análise uni e multivariada não houve correlação cmsignificância estatística entre sobrevida e idade > 45 anos, gênero, KPS no diagnóstico e grau de ressecção. A sobrevida total em6, 12, 18 e 24 meses foi de 96,3%; 72,6%; 58,1%; e 43,5% respectivamente. A duração do tratamento antes da recorrência tevecorrelação positiva (r=0,66) com a sobrevida até 15 meses. Houve correlação (r=0,64) entre duração do uso de TMZ e sobrevidalivre de progressão. Foi observada ainda maior sobrevida (p=0,04) nos pacientes tratados por mais de 12 meses. Conclui-seque os pacientes submetidos a tratamento com TMZ por 15 ciclos tiveram maior sobrevida que os tratados com 6 ou 12 ciclos.

Complications of post-operative seizure prophylaxis in patients submitted to cranial irradiation

The clinical status of patients with malignant intracranial tumors, such as high-grade gliomas, is often aggravated by seizure activity. Phenytoin is typically employed as prophylactic anticonvulsant in this setting. In such patients, severe systemic drug reactions such as erythema multiforme (EM) may occur. However, in a subgroup of patients with brain radiation therapy, EM-like lesions appear to develop in an increased ratio. The acronym ‘EMPACT’ (E: erythema; M: multiform; associated with P: phenytoin; A: and; C: cranial, radiation; T: therapy) has been suggested to best describes this syndrome. In this article, the authors present a case report of a patient treated with phenytoin for seizure prophylaxis, during the post-operative period following resection of a malignant glioma, and who presented a severe cutaneous rash, evolving with serious consequences due to abrupt change of seizure medications. Because of these predictable complications we abandoned our routine institutional protocol which employed phenytoin for seizure prophylaxis for patients in the post-operative period following malignant tumor resection and which expect to be irradiated in the near future. Once both carbamazepine and barbiturates show cross-sensitivity with phenytoin and may interfere with serum levels of chemotherapy drugs, we now advocate, as other worldwide renown neuro-oncological centers, the use of valproate gabapentin, or alternatively, as recent literature guidelines suggests levetiracetam (keppra), for seizure prophylaxis in this select subset of patients.

El estado clínico de los pacientes con tumores malignos intracraneales, como los gliomas de alto grado, es a menudo agravado por la actividad convulsiva. La fenitoína es normalmente empleadaa como anticonvulsivante profiláctico en esto contexto. En estos pacientes, graves reacciones sistémicas, como eritema multiforme (EM) puedem ocurrir. Sin embargo, en un subgrupo de pacientes con terapia de radiación en el cerebro, lesiones de EM, parece que se desarrollan en una proporción mayor. ‘EMPACT’ La sigla (E: eritema, M: multiforme; asociados con P: fenitoína; A: y C: la radiación craneal, T: La terapia) Se ha sugerido que mejor describe este síndrome. En esto artículo, los autores presentan un caso clínico de un paciente tratado con fenitoína para la profilaxia de convulsiones, durante el período post-operatorio después de la resección de un glioma maligno, y que presenta una erupción cutánea grave, que evoluciona con consecuencias graves debido al cambio brusco de medicamentos anticonvulsivos. Debido a estas complicaciones predecibles, que abandonamos nuestro protocolo institucional de rutina que la fenitoína empleadas para la profilaxia de convulsiones en los pacientes en el período post-operatorio después de la resección del tumor maligno y que esperan ser irradiado en un futuro próximo. Una vez que ambos carbamazepina y los barbitúricos mostran sensibilidad cruzada con fenitoína y puede interferir con los niveles séricos de drogas de la quimioterapia, ahora defendemos, como otros centros de renombre mundial neuro-oncológico, el uso de gabapentina valproato, o bien, como orientación la literatura reciente sugiere levetiracetam (keppra), para la profilaxia de las convulsiones en este subgrupo seleccionado de pacientes.

Optimizing costs of intraoperative magnetic resonance imaging. A series of 29 glioma cases.

PURPOSE: The goal of this study was to develop a method to reduce the costs of intraoperative high-field magnet resonance imaging (iMRI). The results of a series of 29 gliomas removed with this technique are presented. METHODS: A series of 29 patients with brain gliomas were operated on using a low-cost method of high-field intraoperative MRI (Signa 1.5 T. MR Excite, GE Inc.). The patients were transported during surgery to the neuroradiological department through a specially located lift in order to perform the intraoperative examinations ("outside iMRI"). The time required for the procedure as well as the possible related complications, such as infection, were analyzed. RESULTS: After studying the intraoperative images, additional tumor resection was needed in 12 of the 29 patients. The median time required to perform the iMRI was 25 min. There was no infection or other complications related to the procedure in this series. CONCLUSIONS: This method offers all clinical advantages of high-field iMRI inside of the operating room, with very low costs and additional advantage of integrating the neurosurgical/ neuroradiological teams. This strategy will give an alternative to several neurosurgical departments in the world to perform high-quality iMRI at very low cost.

Treatment of large and giant residual and recurrent vestibular schwannomas.

This report is a retrospective analysis of the surgical outcome of 15 patients (8 females, 7 males; mean age, 37.8 years) with residual or recurrent vestibular schwannomas operated on between 1987 and 2005. These 15 patients were part of a larger series of 252 consecutive vestibular schwannoma excisions. Tumors were classified as large (10) when their diameter exceeded 3.5 cm and giant (5) when their diameter exceeded 4.5 cm. All patients had previously undergone surgery. Hearing was lost in all cases, 8 had complete facial nerve palsy, 6 had trigeminal nerve deficits, 5 had cranial nerve IX and X palsy, and 10 had ataxic gait. Twelve patients had hydrocephalus. The tumors were reoperated through the retrosigmoid-transmeatal approach. The mean postoperative follow-up was 4.9 years. Complete resection was achieved in all patients. The facial nerve was preserved in 6 of the 7 patients with preoperative facial function. Transient worsening of bulbar cranial nerves palsy occurred in 2 cases. Cerebrospinal fluid leakage occurred in 3 patients. There were no deaths, and the tumors were histologically benign. Surgical removal is the only treatment for these lesions. Total resection associated with a low morbidity rate is possible. Preservation of the facial nerve is difficult due to severe scar tissue.

Tumors of the jugular foramen: diagnosis and management.

OBJECTIVE: Jugular foramen tumors are rare cranial base lesions that present diagnostic and management difficulties. With the availability of new diagnostic procedures these tumors have been more precisely studied and questions of whether, when, and how these lesions should be treated often arise. Data from 106 consecutive patients surgically treated in the past 17 years were retrospectively analyzed to identify surgical outcomes. METHODS: The tumors were approached by a multidisciplinary team composed of neurosurgeons, ear, nose, and throat surgeons, and neuroradiologists. Hypervascular lesions were embolized 3 to 5 days before surgery. The same surgical technique was used to resect all tumors. The surgical defect was covered with vascularized myofascial flaps. The internal carotid artery was infiltrated in two patients, and a saphenous graft bypass was carried out before removal of the lesions. The facial nerve was reconstructed with nerve grafts (great auricular nerve) or XII/VII anastomosis in five cases. Postoperative radiotherapy was carried out for malignant and invasive tumors. RESULTS: Paragangliomas were the most frequent lesions, followed by schwannomas and meningiomas. Complete excision was possible in 89% of benign tumors and 80% of paragangliomas. Lower cranial nerve deficit was the most frequent complication (10 patients, 9.4%), transient in 4 patients. Facial and cochlear nerve paralysis occurred in 8 patients (7.5%). The function of the facial nerve recovered spontaneously in 3 patients. Four patients (3.7%) developed postoperative cerebrospinal fluid leakage. Four patients (3.7%) died after surgery. CONCLUSION: Radical removal of benign jugular foramen tumors is the treatment of choice and may be curative. Large lesions can be radically excised in one surgical procedure with preservation of lower cranial nerves. Cranial base reconstruction with vascularized myofascial flaps reduces the incidence of postoperative cerebrospinal fluid leakage. Damage of the lower cranial nerves is the most serious surgical complication.

Intrinsic tectal low grade astrocytomas: is surgical removal an alternative treatment? Long-term outcome of eight cases.

Low-grade gliomas arising in dorsal midbrain in children and young patients usually present few neurological symptoms and findings, and patients management is controversial. Some authors propose only clinical observation until the patient present signs of increased intracranial pressure when a shunt with or without biopsy, is inserted; others recommend radiotherapy after stereotactic or open biopsy. Microsurgical total removal of tumor may be curative. We present a retrospective analysis of eight patients (mean age 16.6 +/- 11.5 years-old) with low-grade astrocytoma of the tectal region operated on using an infratentorial/supracerebellar approach between 1981 and 2002. All patients presented hydrocephalus and had a shunt insertion before surgical resection of the lesion. The tumour could be totally resected in seven patients. In one case radical removal was not possible due to infiltrative pattern of the lesion. Postoperative radiotherapy was performed in two cases, one patient at the beginning of this series and in the case with infiltrative tumor. This patient presented progressive tumor growth and died five years after surgery. No recurrence occurred after total removal. Post-surgical follow-up time ranged from 2 1/2 to 22 1/2 years (mean 9.9 +/- 5.9 years). Radical microsurgical removal of non invasive tumors is possible without mortality or significant morbidity. It may be curative and should remain as an alternative to be discussed with the patient.