الفهرس 
Radiological anatomy and normal variationOnly 14 pages are availabe for public view
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Abstract
The stomach is involved by spectrum of benign and malignant neoplastic lesions. The clinical manifestations of gastric neoplasms vary from abdominal pain to vague symptoms such as weight loss and anemia. In most cases, Computerized Tomography (CT) is requested to better demonstrate a pathologic process seen or suggested clinically or by other diagnostic means such as upper gastrointestinal radiographic series or endoscopy.
In some cases, gastric disease is first noted on CT scan and may never been seen considered in differential diagnosis before CT examination.
Computed tomography (CT) has proved to be a valuable adjunct to barium studies and endoscopy. CT clearly demonstrated the primary pathologic condition and shows extension of the disease to adjacent or distant structures.
In this essay, different CT techniques used for examination of the stomach such as standard examination of the stomach using gas contrast technique with intravenous contrast administration or spiral CT examination using either positive contrast material as oral gastrographine solution or water contrast material as oral gastrographine solution or water contrast media which allow better visualization of the enhanced wall of the stomach and not interfere with CT angiography like the positive contrast material. Air contrast could be used with the previous such techniques to allow additional distension of the stomach. Air also is negative contrast agent and therefore allows better visualization of the enhanced stomach wall.
Triphasic spiral CT technique used for staging of gastric carcinoma with better evaluation of liver metastases. Three dimensional imaging of the stomach using shaded surface display technique allow the detection and evaluation of the early gastric cancer which become brighter, even endoscopic 3D CT of the stomach may provide an overview of the tumor mass within the lumen of the stomach as seen with gastroscopy. 3D CT stomach has some limitations as creating 3D CT reconstruction is time consuming (about 25-35 min/patient), inability to evaluate distant or lymphangitic metastases and difficulty in detecting flat and small lesions. Lastly virtual endoscopy of the stomach is the most promising technique that allows visualization of the inner surface of the stomach simulates the view traditionally obtained by gastroscopy. All these techniques are presented together for better diagnosis of gastric neoplasms with special emphasis on CT signs and criteria for differentiation of each lesion.
We include in this essay 5 illustrative cases from (British journal of Radiology, 72 (1999)) with different pathological conditions.
Gastric studies have enabled accurate diagnosis and staging of gastric malignancies such as gastric carcinoma, lymphoma and lieomyosarcoma. Better understanding of the need to optimize CT protocols suggests that the diagnostic value of CT in these applications will increase.
In spite of the increasing role of endoscopic ultrasound and magnetic resonance imaging in evaluating the stomach, CT will remain an important cost effective imaging tool.