Three-dimensional images of the human cerebellum in unprecedented detail can be obtained using a new X-ray imaging technique, as scientists from Switzerland, Germany and France have now demonstrated. Using X-ray grating interferometry, they could even visualise individual cells without the use of a contrast agent.
Modern medicine relies heavily on imaging techniques, both for clinical applications such as diagnostics and treatment planning and for fundamental research. However, present-day methods have their limitations. Visible-light microscopy can yield functional information in two and three dimensions, but has limited penetration depth and depth resolution. This is not a problem for X-ray radiography and tomography, which yield excellent two- and three-dimensional images of calcified tissue such as bone and teeth. For soft tissues, however, standard absorption X-ray images suffer from poor contrast. Magnetic resonance imaging solves this problem, but has insufficient spatial resolution to visualise individual cells.
Scientists from the University of Basel (Switzerland), Synchrotron Soleil (France) and the ESRF, together with groups from the Technische Universität München, HASYLAB, the Karlsruhe Institute of Technology (Germany) and the Paul Scherrer Institut (Switzerland), have now succeeded in recording three-dimensional X-ray images of the human brain in which the different types of soft tissue can easily be distinguished, and that even allow the visualisation of individual cells.
X-ray grating interferometry is an X-ray phase-contrast imaging method. Contrast is generated by the refraction of the X-ray beam while passing through matter, rather than by the absorption of the X-rays as in conventional radiography.This imaging method uses grid structures with high aspect ratio and a micrometre-sized pitch that modulates the phase and/or the amplitude profile of the X-ray wavefront.
With its high sensitivity, X-ray grating interferometry has great potential as an imaging method in fundamental biomedical research.
Esta técnica de elevada resolução permite um diagnóstico adequado e como tal, permite um melhor tratamento para doenças.
ResponderEliminarIsto possibilita um grande avanço na pesquisa de doenças ao nível cerebral cujas causas ainda não são conhecidas. Além disso, também possibilita o estudo de áreas do cérebro sobre as quais existe pouca informação mas que, podem trazer descobertas importantes. O facto desta técnica poder visualizar as células individuais é outra grande vantagem pois é cada vez mais importante conhecer os mecanismos a nível celular e ir à raiz do problema, para encontrar novas soluções.
Apesar dos raios-X serem os primeiros a serem utilizados para técnicas de imagem, eles podem ainda trazer grandes avanços e portanto, é uma técnica que deve continuar a ser explorada.
Devemos continuar a procurar no que já existe novos métodos e soluções!
Tânia Vieira