Dedicated Multidetector CT of the Stomach: Spectrum of Diseases

Abstract

Multidetector computed tomography (CT) offers new opportunities in imaging of the gastrointestinal tract. When thin collimation is used, near-isotropic imaging of the stomach is possible, allowing high-quality multiplanar reformation and three-dimensional reconstruction of gastric images. Proper distention of the stomach and optimally timed administration of intravenous contrast material are required to detect and characterize disease. In contrast to gastroscopy and double-contrast studies of the stomach, CT provides information about both the gastric wall and the extragastric extent of disease. Preoperative staging of gastric carcinoma appears to be the main clinical indication for multidetector CT. In addition, multidetector CT allows detection of other gastric malignancies (lymphoma, carcinoid tumors, metastases, gastrointestinal stromal tumors) and benign gastric tumors (neural tumors, polyps). Gastric inflammation (gastritis, ulcers, Ménétrier disease) and miscellaneous gastric conditions (emphysema, gastric outlet obstruction, varices) can also be visualized with multidetector CT. Multidetector CT is a valuable tool for the evaluation of gastric wall disease and serves as an adjunct to endoscopy.

Summation or Axial Slab Average Intensity Projection of Abdominal Thin-section CT Datasets: Can They Substitute for the Primary Reconstruction from Raw Projection Data?

“…In view of these two challenges, the summation (averaging multiple contiguous sections) and axial slab average intensity projection (AIP) of thin-section datasets are particularly interesting, as they reduce the number of images and improve image quality without increase in patient dose by averaging pixel values and therefore canceling image noise across the images. [6][7][8][9] To deal with image overload, many radiologists today are acquiring images using thin collimation and then archiving, filming, and even interpreting images using much thicker (ca 5 mm) section series which are derived from original thinsection datasets by using summation or AIP. [6][7][8][9] Sliding slab AIP is already widely used for the volumetric navigation of thin-section datasets, in which overlapping slabs of a desired thickness are rapidly rendered creating the illusion of continuity from image to image as the user slides the slab along a viewing direction.…”

“…[6][7][8][9] To deal with image overload, many radiologists today are acquiring images using thin collimation and then archiving, filming, and even interpreting images using much thicker (ca 5 mm) section series which are derived from original thinsection datasets by using summation or AIP. [6][7][8][9] Sliding slab AIP is already widely used for the volumetric navigation of thin-section datasets, in which overlapping slabs of a desired thickness are rapidly rendered creating the illusion of continuity from image to image as the user slides the slab along a viewing direction. 6,10,11 Regardless of whether summation and AIP are applied at the time of display in an interactive manner, or at the time of archiving or filming, these techniques are being increasingly used, 6,8,10,[12][13][14] and they are likely to become a primary interpretation mode for thin-section CT datasets, to deal with data overload and to increase image quality.…”

Tumor Estromal Gastrointestinal (Gist): Formas De Presentacion

“…Un 70% se ubican en estómago (4) , un 20-30% en el intestino delgado y un 7% en la región anorrectal. A diferencia del resto del tubo digestivo, en el esófago los leiomiomas son más frecuentes.…”

“…Sin embargo, la observación en el año 1983, que los GISTs expresaban en los estudios inmunohistoquimicos un receptor para el factor de crecimiento de la tirosina kinasa, llamado CD117 en un 100% de los casos, y la proteína CD34 en el 70% de los casos, estableció la diferencia con los tumores mencionados. Otros posibles marcadores tumorales incluyen vimentina, actina, proteína S-100 y desmina.Los GISTs se originan de una célula precursora común, la célula intersticial de Cajal o marcapasos intestinal, o bien de una célula troncal más primitiva de la cual derivan la célula de Cajal y las células musculares lisas (2) .Se pueden localizar en cualquier parte del tracto gastrointestinal, así como también en omento, mesenterio o retroperitoneo.Un 70% se ubican en estómago (4) , un 20-30% en el intestino delgado y un 7% en la región anorrectal. A diferencia del resto del tubo digestivo, en el esófago los leiomiomas son más frecuentes.…”

Endoscopy Induced Gastric Pneumatosis

“…Several causes have been described, emphysematous gastritis being the most lethal. [1][2][3][4] There were no relevant clinical or analytical findings, no signs of pneumatosis in other segments of the gastrointestinal tract or the portal vein. The patient underwent an upper gastrointestinal endoscopy two days before, where two biopsies were performed in the duodenal bulb.…”