Anais da 27º Semana Científica - Hospital de Clínicas de Porto Alegre

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Revista HCPA 2007; 27 (Supl.1)
diagnosticados como malignos, continham histórico familiar presente, correspondendo tão somente 12,6%. As demais 87,4%,
apresentaram histórico familiar ausente. Por outro lado, dentre os 381 pacientes, cujo resultado anátomo-patológico foi negativo,
apenas 12,8% tinham histórico familiar e as demais 87,2% não apresentavam antecedentes familiares da doença. Os resultados
obtidos encontram-se de acordo com a literatura. Considerando as limitações dos dados, ressaltamos a necessidade de elaborar
novos estudos bem como avaliar outras variáveis com o intuito de investigar os fatores de risco que preponderam no Câncer de
mama.
Neurocirurgia
WHITE FIBER DISSECTION TECHNIQUE AND ITS CORRELATION WITH DIFFUSION TRACTOGRAPHY OF
MAGNETIC RESONANCE IMAGING: ITS RULE IN GLIOMA AND EPILEPSY SURGERY
GUSTAVO RASSIER ISOLAN; LEONARDO VEDOLIN; LEANDRO INFANTINI DINI; MARINO MUXFELDT
BIANCHIN, JOSÉ AUGUSTO BRAGATTI; FREDERICO SOARES FALCETTA; LUCAS REZNICEK; MARCO ANTÔNIO
STEFANI.
The fiber dissection technique is an anatomical method that involves peeling away the white matter tracts of the brain to display
its three-dimensional anatomic organization. Early anatomists demonstrated many tracts and fasciculi of the brain using this
technique.Diffusion tractography of magnetic resonance imaging (MRI), such as diffusion tensor tractography, on the other hand,
allows us to visualize white matter tracts in vivo and to study white matter integrity quantitatively. The purpose of this study is
compare the major tracts identified in anatomical dissections and Diffusion tractography MRI. Material and methods: Fifhteen
human cadaveric hemispheres were dissected by one of the authors in two different microsurgical laboratories (Hospital
Beneficência Portuguesa de São Paulo e University of Arkansas for Medical Sciences by using a modification of the method
described by Klingler. The correlation between this anatomy and Diffusion tractography MRI is done. Results: The major tracts
and fasciculi are described under the perspective of these two techniques. The authors discuss the current opinion regarding these
techniques in intrinsic brain gliomas and epilepsy surgery. Conclusion: There is good correlation between both techniques.
Clinical studies must be performed to define the real importance of the diffusion tractography MRI not only in planning the best
corridor to approach tumors and lesions but also as a prognostic factor.
THE IMPORTANCE OF THE PREOPERATIVE VENOUS ANATOMY STUDY IN PLANNING SKULL BASE
APPROACHES TO TREAT CENTRAL NERVOUS SYSTEM TUMORS
GUSTAVO RASSIER ISOLAN; GUSTAVO RASSIER ISOLAN M.D., PHD; LEONARDO VEDOLIN MD; MARCO
ANTÔNIO STEFANI M.D., PHD., ÁPIO CLÁUDIO MARTINS ANTUNES M.D., PHD; FREDERICO FALCETTA M.S.;
OMAR ANTÔNIO DOS SANTOS MD; RAFAEL MODKOVSKI MD; ANDRÉ CERUTTI FRANCISCATO MD; THIAGO
TORRES DE ÁVILA MD
The technical difficulty of using the skull base approaches and the likelihood of encountering venous complications depend on the
particular temporal venous anatomy. To reduce such potential risks, neurosurgeons must have adequate knowledge of the
variations in the anatomy of the temporal venous drainage system, particularly of the temporal bridging veins. Based on this, a
detailed preoperative study of the drainage pattern of the superficial venous system is paramount to decide the best approach to
treat central nervous system tumors. The purpose of this study is present our current approach regarding this issue in our patients.
A brief review of the superficial venous anatomy is presented and the imaging methods are discussed.
THE PARADIGM OF SKULL BASE APPROACHES TO TREAT CENTRAL NERVOUS SYSTEM TUMORS: PART I: THE
PETROSAL APPROACH
GUSTAVO RASSIER ISOLAN M.D., PHD; MARCO ANTÔNIO STEFANI M.D., PHD., ÁPIO CLÁUDIO MARTINS
ANTUNES M.D., PHD; FREDERICO FALCETTA M.S.; OMAR ANTÔNIO DOS SANTOS MD; RAFAEL MODKOVSKI
MD; ANDRÉ CERUTTI FRANCISCATO MD; THIAGO TORRES DE ÁVILA MD
Introduction: The petrosal approach provides excellent access to the petroclival region, the basilar trunk and apex, the
anteromedial midbrain and the pons. To acess these regions the petrosal approach offers a number of advantages: (1) the
surgeon’s operative distance to these regions is shorter than in retrosigmoid approaches. (2) There is minimal retraction of the
cerebellum and temporal lobe. (3) The neural structures (seventh and eight nerve) are preserved. (4) The otologic structures
(cochlea, labyrinth, semicircular canals ) are preserved. (5) Finally, the major venous sinuses (transverse and sigmoid), along with
the vein of Labbe and other temporal and basal veins, are preserved. Material and Methods: The petrosal approach was performed
in ten cadaveric specimens at the Microsurgical Laboratory (University of Arkansas for Medical Sciences). Two cases operated at
the Hospital de Clínicas de Porto Alegre are presented to illustrate this approach. These cases were a huge tentorial and petrosal
meningeomas, respectively. Results: the surgical steps patient position, craniotomy flap, cutting the tentorium and closure are
described, as well as the microsurgical anatomy. The tumor total resection was achieved in both patients without postoperative
deficits. Conclusion: The petrosal approach is intended to gain direct access to the petroclival and perimesencephalic regions
while avoiding some of the complications associated with other approaches to this area.