RESUMO
OBJECTIVE: A computerized version of the Schaltenbrand and Wahren's stereotactic brain atlas for image-guided functional neurosurgery planning has been developed and integrated into our PC-based planning system. METHODS: The SW atlas plates were digitized, contoured and labeled for both hemispheres. The computerized atlas may be interactively registered with patient's data using linear and non-linear transformation. The implemented computational tools and applications are presented. RESULTS: Our computer system permits navigation through original or reconstructed slices, multiple-views synchronization and zoom to improve the localization of the commisures and the surgical targets, likewise the optimum path selection. Atlas position in the target's region can be interactively actualized and lesion's position and volume may be simulated. CONCLUSIONS: Its benefits of this approach include increased accuracy of target definition, decreased the number of electrode tracts and for instance the time of the surgery, and reduced surgical complications.
Assuntos
Mapeamento Encefálico/instrumentação , Encéfalo/anatomia & histologia , Encéfalo/cirurgia , Procedimentos Neurocirúrgicos/métodos , Cirurgia Assistida por Computador/instrumentação , HumanosRESUMO
The implementation of effective methods of testing the precision of computations, is essential for the development of medical systems, such as the stereotactic planning software for neurosurgery. During the development of our planning system we designed, in addition to the traditional phantom test, some tests based on digitally constructed images. These tests give quantitative and qualitative measurement of the precision and stability of the calculations, and are easy to implement and isolate the program error from the mechanical and image acquisition errors. The verification of our software shows good precision in coordinates calculation and a significant impact of pixel size and interscan spacing on the precision.
Assuntos
Técnicas Estereotáxicas , Terapia Assistida por Computador/métodos , Encéfalo/cirurgia , Calibragem , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Software , Validação de Programas de ComputadorRESUMO
OBJECTIVE: The objective of this paper was to review information related to the various factors which may trigger the mechanisms of cell death, induced or programmed, which take place in the nervous system and their relationship with the aetiopathogenesis of the neurodegenerative diseases. DEVELOPMENT: In recent years it has been recognized that cell death may be not only the consequence of accidental damage but also a sign of a suicide programme. This form of death is currently known as apoptosis. It is a process which is morphologically distinct from accidental cell death or necrosis. It does not cause an inflammatory response. This type of death is not only involved in the development and haemostasis of tissues, but also in setting off neuronal degeneration in experimental models of Parkinson's disease, Huntington's chorea, etc. CONCLUSIONS: In the cell death occurring in neurodegenerative diseases there is more than one induction mechanisms. Understanding the factors which trigger cell death, and the chain of events leading to this, gives grounds for the design of new pharmacological strategies for the treatment of these diseases.