Paulo Henrique Pires Aguiar

Esthesioneuroblastomas with intracranial extension: proliferative potential and management

A total of 15 patients with esthesioneuroblastomas were treated between 1978 and 1992 at the Neurosurgery Department, Nordstadt Hospital, Hannover. In 9 cases, the tumors invaded the anterior cranial fossa. One patient died before any surgical intervention. Eight tumors were operated by a combined paranasal and subfrontal approach. Gross total tumor removal was achieved in all cases. Apart from anosmia, the only postoperative complication was transient mental changes in one case. Immunohistochemical analyses with MIB 1 monoclonal antibodies, directed against recombinant parts of Ki-67 antigen, were performed to estimate the proliferative potential of the esthesioneuroblastomas. Most of the tumors showed high proliferating cell indexes, which ranged from 3 to 42% (mean, 16%). The proliferating cell index with MIB 1 showed a correlation with postoperative outcome, although this was not statistically significant. Esthesioneuroblastomas can be totally removed surgically. The proliferating cell index may reflect histologically the biological behavior of tumor. Long-term follow-up is mandatory, and immunohistochemical studies may be of help in predicting outcome.

Brainstem cavernomas: a surgical challenge

OBJECTIVE The authors show their experience with brainstem cavernomas, comparing their data with the ones of a literature review. METHODS From 1998 to 2009, 13 patients harboring brainstem cavernomas underwent surgical resection. All plain films, medical records and images were reviewed in order to sample the most important data regarding epidemiology, clinical picture, radiological findings and surgical outcomes, as well as main complications. RESULTS The mean age was 42.4 years (ranging from 19 to 70). No predominant gender: male-to-female ratio, 6:7. Pontine cases were more frequent. Magnetic resonance imaging was used as the imaging method to diagnose cavernomas in all cases. The mean follow-up was 71.3 months (range of 1 to 138 months). Clinical presentation was a single cranial nerve deficit, VIII paresis, tinnitus and hearing loss (69.2%). All 13 patients underwent resection of the symptomatic brainstem cavernoma. Complete removal was accomplished in 11 patients. Morbidity and mortality were 15.3 and 7.6%, respectively. CONCLUSIONS Cavernomas can be resected safely with optimal surgical approach (feasible entry zone) and microsurgical techniques, and the goal is to remove all lesions with no cranial nerves impairment.

Anatomia microcirúrgica da artéria carótida externa: um estudo estereoscópico

CONTEXTO: O conhecimento das estruturas anatomicas da arteria carotida externa por meio do estudo estereoscopico pode determinar melhores resultados em microcirurgias da arteria carotida externa. OBJETIVO: Descrever as estruturas da arteria carotida externa sob a visao estereoscopica, identificando seus multiplos aspectos. METODOS: Doze regioes cervicais foram dissecadas, utilizando-se microscopico cirurgico com 3 a 40x de aumento. As disseccoes anatomicas foram documentadas utilizando-se a tecnica para obtencao de imagens tridimensionais (3D), objetivando a producao de impressoes estereoscopicas. RESULTADOS: O uso da tecnica estereoscopica possibilitou a abordagem da circulacao arterial extracraniana, sendo realizados estudos cirurgicos do tipo combinado fossa posterior e fossa infratemporal, tornando as microcirurgias e os procedimentos neurocirurgicos vasculares mais precisos. CONCLUSAO: O uso das imagens obtidas pela tecnica estereoscopica produziu um resultado mais assertivo em relacao ao estudo da anatomia para a microcirurgia e procedimentos neurocirurgicos, facilitando melhor aprendizado previamente a realizacao de procedimentos complexos em neurocirurgia.

Prospective factors of temporary arterial occlusion during anterior communicating artery aneurysm repair.

INTRODUCTION This study was undertaken to determine variables that could predict, in the perioperative period of anterior communicating artery (ACom) aneurysms surgeries, the likelihood of postoperative sequelae and complications, after temporary arterial occlusion (TAO). PATIENTS AND METHODS In a universe of 32 patients submitted to ACom aneurysm repair in the last 7 years, 21 needed TAO intraoperatively, and had their data examined retrospectively. RESULTS Aneurysms larger than 7 mm were more likely to be treated with longer TAO time than small aneurysms, (p < 0.0001). There was no statistical correlation between time of occlusion and outcome. Age, Glasgow Coma Scale at initial evaluation, and Fisher scale at first CT scanning were independent factors of unfavorable outcome (p < 0.001). Meanwhile gender, tobacco addiction, obesity, arterial hypertension, dyslipidemia, location of TAO (A1 or A2), intraoperative rupture (IR) and the aneurysm size were not identified as independent prognostic factors.During follow-up period, two thirds of the patients had a favorable outcome, accomplishing normal daily life activities without major complications. Most patients developed clinical vasospasm (66.6 %), with 19 % of the patients harboring a severe disease. Delayed ischemic neurological deficit was observed in 28.5 %, without any statistical correlation to time of TAO or IR. CONCLUSION TAO during ACom aneurysm repair does not seem to add more morbidities to the procedure, and is not an independent prognostic factor.

Abscesso cerebelar por Nocardia: relato de caso

The authors describe a case of cerebellar abscess by Nocardiain a patient with the acquired immunodeficiency syndrome (AIDS) that was submitted to a posterior fossa craniectomy for diagnosis and treatment. Pathological and neuroimage findings are discussed as well as the surgical approach taking into account literature data on the subject.

Feasibility and Limitations of the Retrosigmoid and Presigmoid Approaches Combined With the Anterior Petrosal Approach to Meningiomas in the Petroclival Area

Meningiomas located in the petroclival junction are difficult lesions to manage. Usually, they are diagnosed when they become large-sized symptomatic lesions and extend to adjacent areas. The curative treatment is surgical resection, but the intricate and eloquent neurovascular anatomy of the petroclival complex and adjacent areas challenges the surgeon while considering total tumor resection against the acceptable morbidity and mortality. The authors report 10 case series of tumors arising from or extending to the petroclival junction; they included 10 meningiomas: 4 petroclival, 3 sphenopetroclival, 2 tentorial at the petroclival area, and 1 anterior petrosal operated from 2007 to 2011 in the Hiroshima University Hospital. They were subjected to the combined approaches: anterior petrosal, presigmoid, and retrosigmoid. The translabyrinth approach was added in 2 cases where hearing was previously lost. Gross total resection was possible in 6 cases. The mortality rate was 0. The main complications were postoperative cerebrospinal fluid leak in 1 case, permanent cranial nerve palsy in 3 cases, and venous congestion in 1 case. The main limiting factors for good outcome are the tumor size, wide attachment, hard consistency, bleeding, and preoperative clinical status. Involvement of the basilar artery and perforators, attachment to the brainstem, and avoidance of venous damage are also important points to be considered. As a rule, the anterior petrosal approach yields direct access to the tumor attachment, permitting early devascularization, and direct approach to medial cranial fossa base content. The retrosigmoid is necessary when the tumor is very large and has extended below the internal acoustic meatus. The presigmoid access is useful for cases where the tumors extend to the medial cranial fossa; it reduces the required amount of retraction of the temporal lobe, as it permits the surgeon to change the angle of attack from the lateral to the inferior range.