Résumé
Hay una gran variedad de artefactos en imágenes que se producen por la interacción entre los equipos y el paciente. Reconocerlos es importante, ya que pueden inducir informes erróneos o encubrir una patología. Por ello, una vez detectados, es necesario emplear técnicas para su eliminación. Describimos los artefactos más frecuentes en tomografía computada y resonancia magnética.
A wide variety of artefacts are observed in diagnostic imaging. They are caused by the interaction between the equipment and the patients. To recognise them is important, because they can induce pitfalls in the reports or mask some disease. Once they have been detected, it is necessary to apply techniques in order to elimínate them. A description is presented of the most common artefacts in computed tomography and magnetic resonance imaging.
Sujets)
Humains , Mâle , Femelle , Spectroscopie par résonance magnétique , Tomodensitométrie , Artéfacts , Imagerie diagnostique , Techniques et procédures diagnostiquesRésumé
Recent advances have allowed the identification and characterization of well defined vesicular subcellular organelles involved in multiple basic cellular physiological processes, with demonstrated clinical relevance. Among these, three particular subcellular organelles have received special attention based on their proven and postulated participation in the sorting and targeting of small-and large-molecular weight molecules during exocytosis and endocytosis, and in cell signaling and transduction events. These have characteristic proteinaceous coat structures that allows their classification accordingly, into what has been described as clathrin coated vesicles and COP-coated vesicles and caveolae. In this review article a brief description of clathrin-coated vesicles and COP-coated vesicles is presented. Caveolae (CAV), in turn, constitute a novel subcellular organelle that has received special attention based on its proven and postulated participation in transcytosis, potocytosis, and in cell signaling and transduction events. In this review of the literature a more extensive discussion is presented of CAV. In this context the article discusses the structural features of caveolae, its constituent protein caveolin(s), the functional aspects of this new organelle, and its postulated clinical relevance