OBJECTIVE The authors sought to construct, implement, and evaluate an interactive and stereoscopic resource for teaching neuroanatomy, accessible from personal computers. METHODS Forty fresh brains (80 hemispheres) were dissected. Images of areas of interest were captured using a manual turntable and processed and stored in a 5337-image database. Pedagogic evaluation was performed in 84 graduate medical students, divided into 3 groups: 1 (conventional method), 2 (interactive nonstereoscopic), and 3 (interactive and stereoscopic). The method was evaluated through a written theory test and a lab practicum. RESULTS Groups 2 and 3 showed the highest mean scores in pedagogic evaluations and differed significantly from Group 1 (p < 0.05). Group 2 did not differ statistically from Group 3 (p > 0.05). Size effects, measured as differences in scores before and after lectures, indicate the effectiveness of the method. ANOVA results showed significant difference (p < 0.05) between groups, and the Tukey test showed statistical differences between Group 1 and the other 2 groups (p < 0.05). No statistical differences between Groups 2 and 3 were found in the practicum. However, there were significant differences when Groups 2 and 3 were compared with Group 1 (p < 0.05). CONCLUSIONS The authors conclude that this method promoted further improvement in knowledge for students and fostered significantly higher learning when compared with traditional teaching resources.

The white fiber dissection technique is a valuable tool for understanding the three-dimensional disposition of the anatomic structures. The lateral mesencephalic sulcus, the peritrigeminal area, and the inferior olivary nucleus provide surgical spaces and delineate the relatively safe alleys where the brainstem can be approached without injuring important neural structures.

RESUMOO traumatismo cranioencefálico (TCE) é a principal causa de morte e sequela em crianças e adultos jovens nos países industrializados ocidentais. A lesão encefálica definitiva que se estabelece após o TCE é o resultado de mecanismos fisiopatológicos que se iniciam com o acidente e estendem-se por dias ou semanas. As lesões encefálicas no TCE podem ser classificadas em difusas e focais. Esses dois mecanismos costumam associar-se em um mesmo paciente, embora, geralmente exista o predomínio de um tipo. O conhecimento dos mecanismos fisiopatológicos da lesão cerebral no traumatismo cranioencefálico é fundamental para o estabelecimento de medidas terapêuticas clínicas e cirúrgicas. Neste artigo, realizamos uma revisão crítica da literatura sobre os princípios fisiopatológicos da lesão cerebral no paciente com traumatismo cranioencefálico. UNITERMOS FISIOPATOLOGIAA lesão encefálica definitiva que se estabelece após o TCE é o resultado de mecanismos fisiopatológicos que se iniciam com o acidente e se estendem por dias a semanas. Assim, do ponto de vista didático, as lesões cerebrais são classificadas em primárias e secundárias 8 . As lesões primárias são aquelas que ocorrem no momento do trauma. No paciente com ferimentos por projétil de arma de fogo ou arma branca que penetram o crânio, a lesão primária ocorre em virtude do trauma direto ao parênquima encefálico. Por outro lado, nos traumatismos fechados, caracterizados quando não ocorre contato com o conteúdo intracraniano, as lesões primárias podem resultar da movimentação cerebral associada à energia cinética do acidente. Nas lesões decorrentes de forças de aceleração e desaceleração não é necessário o impacto do crânio contra estruturas externas. Como o encéfalo e a caixa craniana possuem densidades diferentes, quando submetidos às mesmas forças inerciais, respondem de forma desigual. Esse descompasso de movimentos pode promover a ruptura de veias cerebrais que desembocam nos seios durais, bem como impacto e laceração do parênquima contra as estruturas rígidas do crânio. Somado a esse mecanismo como a região central do encéfalo é relativamente fixa em virtude da presença do tronco encefálico, as regiões periféricas do cérebro e cerebelo tendem a apresentar maior amplitude de movimento. Essa diferença na amplitude dos movimentos entre a região central e a periférica do encéfalo gera o estiramento de axônios e de vasos sanguíneos cerebrais, o que pode resultar desde uma disfunção temporária até ruptura dessas estruturas 9,10 . As lesões secundárias decorrem de agressões que se iniciam após o momento do acidente, resultantes da interação de fatores intra e extracerebrais, que se somam para inviabilizar a sobrevivência de células encefálicas poupadas pelo trauma inicial. No local do acidente, intercorrências clínicas como hipotensão arterial, hipoglicemia, hipercarbia, hipóxia respiratória, hipóxia anêmica e distúrbios hidroeletrolíticos são os principais fatores de lesão secundária. Posteriormente, são somados outros distúrbios metabólicos e infecciosos sistêmi...

We systematically reviewed the literature concerning the anterior cranial fossa schwannomas to understand their pathogenesis, determine their origin, and standardize the terminology. We performed a MEDLINE, EMBASE, and Science Citation Index Expanded search of the literature; age, gender, clinical presentation, presence or absence of hyposmia, radiological features, and apparent origin were analyzed and tabulated. Cases in a context of neurofibromatosis and nasal schwannomas with intracranial extension were not included. Age varied between 14 and 63 years (mean ¼ 30.9). There were 22 male and 11 female patients. The clinical presentation included seizures (n ¼ 15), headache (n ¼ 16), visual deficits (n ¼ 7), cognitive disturbances (n ¼ 3), and rhinorrhea (n ¼ 1). Hyposmia was present in 14 cases, absent in 13 cases (39.3%), and unreported in five. Homogeneous and heterogeneous contrast enhancement was observed in 14 and 15 cases, respectively. The region of the olfactory groove was the probable site in 96.5%. Olfactory tract could be identified in 39.3%. The most probable origin is the meningeal branches of trigeminal nerve or anterior ethmoidal nerves. Thus, olfactory groove schwannoma would better describe its origin and pathogenesis and should be the term preferentially used to name it.

T he primary goal of intracranial aneurysm treatment is complete, permanent, and safe aneurysm occlusion while maintaining flow in the vessels associated with the aneurysm. Aneurysms are very diverse; therefore, the surgical approach depends in large part on the specific aneurysm to be treated, its relationship to the skull, the surrounding structures, and morphology. In this context, the pterional (PT), or frontotemporosphenoidal, approach is one of the most commonly used in vascular neurosurgery. 1,2,6,12,[26][27][28] abbreviatioNs MPT = minipterional; mRS = modified Rankin Scale; PT = pterional; ROI = region of interest. methods Fifty-eight patients with ruptured and unruptured anterior circulation aneurysms were enrolled into a prospective randomized study. The first group included 28 patients who underwent the MPT technique, and the second group comprised 30 patients who underwent the classic PT craniotomy. To evaluate the aesthetic effects, patients were asked to grade on a rule from 0 to 100 the best and the worst aesthetic result. Photographs were also taken, assessed by 2 independent observers, and classified as showing excellent, good, regular, or poor aesthetic results. Furthermore, quantitative radiological assessment (percentage reduction in thickness and volumetric analysis) of the temporal muscle, subcutaneous tissue, and skin was performed. Functional outcomes were compared using the modified Rankin Scale (mRS). Frontal facial palsy, postoperative hemorrhage, cerebrospinal fistula, hydrocephalus, and mortality were also analyzed. results Demographic and preoperative characteristics were similar in both groups. Satisfaction in terms of aesthetic result was observed in 19 patients (79%) in the MPT group and 13 (52%) in the PT group (p = 0.07). The mean score on the aesthetic rule was 27 in the MPT group and 45.8 in the PT group (p = 0.03). Two independent observers analyzed the patient photos, and the kappa coefficient for the aesthetic results was 0.73. According to these observers, excellent and good results were seen in 21 patients (87%) in the MPT and 12 (48%) in the PT groups. The degree of temporal muscle, subcutaneous tissue, and skin atrophy was 14.9% in the MPT group and 24.3% in the PT group (p = 0.01). Measurements of the temporal muscle revealed 12.7% atrophy in the MPT group and 22% atrophy in the PT group (p = 0.005). The volumetric reduction was 14.6% in the MPT and 24.5% in the PT groups (p = 0.012). Mortality and mRS score were similar in both groups at the 6-month evaluation (p = 0.99). coNclusioNs Minipterional craniotomy provides clinical results similar to those of the PT technique. Moreover, it provides better cosmetic results. It can be used safely and effectively to surgically treat aneurysms of the anterior circulation instead of the PT approach.Clinical trial registration no.: NCT01872741 (clinicaltrials.gov)

BackgroundPneumocephalus (PNC) is defined as a pathological collection of gas within the cranial cavity. The authors studied the effects of hyperbaric oxygenation (HBO2) therapy on a group of patients with PNC, comparing them with a control group to determine the relative impact on pneumocephalus volume, clinical symptoms, and duration of hospitalization.MethodsTwenty-four patients with PNC treated at our hospital were consecutively studied. These patients were divided into a treated group (n=13) and a control group (n=11). Thirteen patients (treated group) were treated with HBO2 therapy sessions in a monoplace hyperbaric chamber at 2.5 atmospheres with 100% oxygen concentration. The control group was treated with normobaric oxygenation.ResultsClinical improvement was seen in all patients. In the treated group, a decrease of the gas bubble was observed on the computerized tomography scan after each session of HBO2. The treated group also experienced a lower rate of meningitis compared with the control group. The length of hospital stay was significantly higher in the control group compared with the treated group.ConclusionsHBO2 therapy in selective cases may lead to clinical and radiological improvement in patients with PNC.

-Pilocytic astrocytoma (PA) is a benign tumor that rarely spread along the neuraxis. At the moment there are no more than five cases of leptomeningeal dissemination (LD) from PA at diagnosis described in the literature. Different patterns of presentation or recurrence may be noted: local recurrence, malignant transformation, multicentric disease or metastatic disease. LD and multicentric disease can be distinct pathological entities. We report two cases and analyse literature, emphasizing leptomeningeal spread at presentation. Hydrocephalus, biopsy and parcial ressection are likely to be favorable factors to the occurrence of LD. Otherwise, LD may be part of natural history of PA, as evidenced by its ocurrence in non-treated cases.KEY WORDS: pilocytic astrocytoma, leptomeningeal dissemination, multicentric disease, cerebrospinal fluid, metastasis, radiation therapy, chemotherapy, hydrocephalus.Disseminação leptomeníngea de astrocitoma pilocítico ao diagnóstico: relato de dois casos. Disseminação leptomeníngea de astrocitoma pilocítico ao diagnóstico: relato de dois casos. Disseminação leptomeníngea de astrocitoma pilocítico ao diagnóstico: relato de dois casos. Disseminação leptomeníngea de astrocitoma pilocítico ao diagnóstico: relato de dois casos. Disseminação leptomeníngea de astrocitoma pilocítico ao diagnóstico: relato de dois casos.RESUMO -Astrocitoma pilocítico (AP) é tumor benigno que raramente se dissemina ao longo do neuroeixo. Até o momento não há mais que cinco casos de AP que se tenham apresentado com disseminação leptomeníngea (DL) descritos na literatura. Diferentes padrões de apresentação ou recorrência podem ser observados: recorrência local, transformação maligna, doença multicêntrica ou doença metastática. DL e doença multicêntrica podem ser entidades diferentes. Relatamos dois casos e analisamos a literatura. Hidrocefalia, biópsia e ressecção parcial são provavelmente fatores predisponentes à DL. Por outro lado, DL pode ser parte da história natural de AP, como pode ser evidenciado pela sua ocorrência em casos não tratados.

This study shows that pseudoaneurysms and active extravasation of contrast are common findings in this subset of patients. Although the natural history of these lesions is still poorly understood, additional investigation with ipsilateral external carotid angiography may be recommended, considering the potentially catastrophic consequences of late rupture.