Gustavo Rassier Isolan
Universidade Federal do Rio Grande do Sul
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Featured researches published by Gustavo Rassier Isolan.
Neurological Research | 2010
Paulo Henrique Aguiar; Rogério Aires; Edward R. Laws; Gustavo Rassier Isolan; Angela Flavia Logullo; Chirag G. Patil; Laurence Katznelson
Abstract Objective: The present article presents an overview of the literature, and analyses the methods and the primary questions related to assessment of proliferation index using the Ki-67/MIB-1 labeling index in pituitary adenomas. Although atypical adenomas are characterized by their atypical morphological features by an elevated mitotic index, a Ki-67 (MIB-1) labeling index greater than 3% and extensive nuclear staining for p53, use of the proliferation index (LI) of pituitary adenomas in assessing the degree of tumor aggressiveness is a controversial topic in the literature, and there are disparate results involving many studies. Methods: A review of literature was carried out to correlate the role of Ki-67 LI and its correlation with clinical findings, tumor size, invasiveness, recurrence, adenoma subtype, adenoma doubling time, and pituitary carcinomas is addressed. Results: The prognosis cannot be predicted on the basis of the Ki-67 LI alone. Although there is no direct relation between Ki-67 LI and some of these variables and controversial data were found regarding some topics, our review justify the use of Ki-67 in the analysis of pituitary adenomas as an additional information for clinical decision. Conclusion: Although assessment of proliferative may be helpful in predicting subsequent tumor recurrence or invasiveness, there are many other important and as yet unidentified factors pituitary tumors. It is clear that further research is needed to clarify these molecular mechanisms to predict those with a potentially poor clinical outcome.
Pituitary | 2009
Gustavo Rassier Isolan; Paulo Henrique Aguiar; Edward R. Laws; Atahualpa Cauê Paim Strapasson; Otavio Bejzman Piltcher
The knowledge of the normal anatomy and variations regarding the management of tumors of the sellar region is paramount to perform safe surgical procedures. The sellar region is located in the center of the middle cranial fossa; it contains complex anatomical structures, and is the site of various pathological processes: tumor, vascular, developmental, and neuroendocrine. We review the microsurgical anatomy (microscopic and endoscopic) of this region and discuss the surgical nuances regarding this topic, based on anatomical concepts.
Neurosurgical Focus | 2010
Gustavo Rassier Isolan; Marino Muxfeldt Bianchin; José Augusto Bragatti; Carolina Machado Torres; Gilberto Schwartsmann
Hallucinations can be auditory, visual, tactile, gustatory, or olfactory, and can be caused by psychiatric (such as schizophrenia and depression), neurological (such as cerebrovascular accidents, neoplasia, and infection), or endocrine and metabolic disorders. Musical hallucinations related to neurological disorders are rare. The authors present a case of a patient with a right insular glioma who developed transient musical hallucinations after microsurgical resection of the tumor.
Pituitary | 2013
Gerson Evandro Perondi; Gustavo Rassier Isolan; Paulo Henrique Pires Aguiar; Marco Antonio Stefani; E. Frederico Falcetta
The transsphenoidal approach is the preferred access used in surgical treatment of most sellar region pathologies. The use of endoscopy is advantageous, and it is considered a good alternative to the traditional microsurgical technique. The purpose of this study is to recognize and describe anatomical variations of the sphenoid sinus and the sellar region, mainly describing the anatomy of the posterior wall of the sphenoid sinus and analyzing intercarotid distances in 3 regions. Thirty sphenoid blocks treated with formaldehyde were injected and dissected. Using endoscopy, anatomical variations were studied and the intercarotid distances were measured at the tuberculum sellae, sellar floor and clivus. The types of sphenoid sinus found were: conchal in 1 (4.76xa0%), pré-sellar in 2 (9.52xa0%) and sellar in 19 (85.7xa0%) specimens. The mean distance found from the sphenoid sinus ostium to the sella turcica was 19xa0mm (±6.5)xa0mm. The mean intercarotid distances found at the tuberculum sellae, sellar floor and clivus were respectively 13.32, 18.00 and 18.90xa0mm. Endoscopy, with its magnification and lighting provide a panoramic view of deep fields. The anatomical variations described in this study support the need for a careful evaluation of preoperative images in each case.
Arquivos De Neuro-psiquiatria | 2001
Pasquale Gallo; Leandro Infantini Dini; Glauco André Saraiva; Ildo Sonda; Gustavo Rassier Isolan
The purpose of this article is to describe the clinical and pathological features of metastatic angiosarcoma in the central nervous system. Only a few cases of cerebral metastasis from angiosarcoma of the heart have been recorded in the literature; particularly related to intracerebral hemorrhage. A case of secondary cerebral angiosarcoma of the heart in a 33 years old man is presented. The initial symptoms were headache, vomiting, lethargy and aphasia. There was a mass in the left temporal lobe with hemorrhage and edema on the computerized tomography (CT). After 24 hours the neurological status worsened and another CT scan showed rebleeding on the tumor area. He underwent an emergency craniotomy but died two days after. Considering the longer survival of sarcoma patients with new modalities of treatment, the incidence of brain metastasis may increase, demanding a better preventive and more aggressive approach. Besides, due to the hemorrhagic nature of such lesions, we suggest the immediate surgery to prevent a fast and lethal evolution because rebleeding.
Journal of Neurology and Neurophysiology | 2011
José Augusto Bragatti; Carolina Machado Torres; Gustavo Rassier Isolan; Marino Muxfeldt Bianchin
People with epilepsy (PWE) have an increased risk for cognitive, behavioral, and psychosocial disorders. The presence of comorbidities may directly affect quality of life of PWE. For example, there is an increased risk for suicide in PWE, compared to the general population. Association between epilepsy and mental disorders is a condition known since Antiquity, and its ranges from 20 to 50%, reaching 80% in selected populations, like individuals with temporal lobe epilepsy (TLE), and medically intractable patients, candidates to surgical treatment, and these indices are far superior to those found in general population (10-20%). Risk factors for the main psychiatric comorbidities in PWE (depression, anxiety and psychosis) are classified in (1) neurobiological, (2) psychosocial, and (3) pharmacological nfactors. There is a bidirectional relationship between epilepsy and mental disorders, namely, not only the epileptic disorder can antedate settlement of psychiatric symptoms in a given patient, but also the diagnosis of mood and behavioral disorders may be made before a first epileptic seizure. This bidirectionality suggests that structural and functional modifications of one disease increase the risk for the development of the other. In this review, we included the most recent articles concerning the terms “mental disorders”, “epilepsy”, and “risk factors” in PubMed. Book chapters were also referred for this work. We gave preference for population-based studies, especially those with nmore than 100 patients studied.
Einstein (São Paulo) | 2012
Paulo Henrique Pires Aguiar; Carlos Alexandre Martins Zicarelli; Gustavo Rassier Isolan; Apio Cláudio Martins Antunes; Rogério Aires; Sérgio Murilo Georgeto; Adriana Tahara; Fahd Haddad
OBJECTIVEnThe authors show their experience with brainstem cavernomas, comparing their data with the ones of a literature review.nnnMETHODSnFrom 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.nnnRESULTSnThe 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.nnnCONCLUSIONSnCavernomas 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.
Jornal Vascular Brasileiro | 2012
Gustavo Rassier Isolan; Adamastor Humberto Pereira; Paulo Henrique Pires Aguiar; Apio Cláudio Martins Antunes; João Pedro Mousquer; Marcel Rozin Pierobon
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.
Clinical Neurology and Neurosurgery | 2017
Sâmia Yasin Wayhs; Guilherme Lepski; Leonardo Frighetto; Gustavo Rassier Isolan
Surgical resection of petroclival meningiomas remains challenging due to their deep location and relationship to vital neurovascular structures. Although the natural history of these tumors involves a slow course, the incidence of cranial nerve deficits and the extent of tumor resection vary widely in the literature. Some reviews on this topic have been conducted, but data remain fragmentary and based on retrospective case series, which hinders attempts at meta-analysis. Within this context, research into the use of minimally invasive approaches, including in neuroendoscopy, continues to emerge. The objective of this narrative review is to analyze the available literature on the surgical treatment of petroclival meningiomas, with a focus on attempts at endoscopy-assisted resection.
Journal of Epilepsy and Clinical Neurophysiology | 2010
Gustavo Rassier Isolan; Marino Muxfeldt Bianchin; Carolina Machado Torres; José Augusto Bragatti; Juliana Bohn Assman; Frederico Soares Falcetta
STUDY DESIGN: Two case reports of a choroidal fissure cyst in the temporal horn associated with complex partial seizure. OBJECTIVES: To describe the clinical course, image findings and literature review of choroidal fissure cysts. SUMMARY AND BACKGROUND DATA: there are few reported cases of choroidal fissure cysts. RESULTS: We report two patients with complex partial seizures and temporal choroidal fissure cysts. The seizures were controlled in both patients. CONCLUSION: The choroidal fissure cyst diagnosis must highlight the importance of considering this lesion in the differential diagnosis of temporal lobe cyst and temporal lobe seizure.