الفهرس 
Anatomical Considerations Anatomy of the StomachOnly 14 pages are availabe for public view
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Abstract
Gastric malignant neoplasms represent one of the major causes of death from malignant disease worldwide. Optimal staging is extremely valuable in the choice of accurate plan of management, thus reducing mortality rate.
Preoperative staging has often included endoscopic ultrasonography (US) and computed tomography (CT).
Endoscopic ultrasonography has been reported to be the most effective diagnostic modality for T staging of gastric cancer as it can detect the gastric wall with five layers of its internal structures; however, it has limitations in the depth of the field of view and it is operator dependant.
Actually, recent advances in CT technology and 3D imaging software have sparked renewed interest in the imaging of the gastrointestinal tract and multidetector CT has offered several potential advantages over single-section techniques; these advantages include: faster data acquisition, greater anatomic coverage, and comparable coverage times with much thinner section collimation together with better resolution. It also allows high-quality multiplanar reformation and three dimensional reconstructions of different images.
There are several pathologies affecting the stomach with different MDCT representations, these pathologies include: adenocarcinoma, lymphoma, gastrointestinal stromal tumors, neuro-endocrine tumors, and metastases.
With the aid of MDCT and the more recent advances in visualization of the stomach as using water as a contrast media, it was possible to identify the lesion more. The usage of water allowed better evaluation of the enhancing gastric wall and allowed better detection of subtle disease. It also does not interfere with 3D imaging and CT angiography.
Helical CT with two-phase scanning is effective for identifying the unique enhancement patterns of early gastric cancer. Contrast-enhanced images obtained during the arterial phase proved useful for tumor detection. Contrast-enhanced CT images obtained during the portal venous phase are helpful for N and M staging.
The use of MPRs allows the radiologist to choose an optimal imaging plane to accurately evaluate the depth of tumor invasion of the gastric wall and to identify the thin fat plane between the tumor and adjacent organs to avoid the partial-volume averaging effect. MPRs were proved to be superior to transverse images in T staging not only because of thinner sections but also because of optimal imaging planes. The use of the combination of virtual gastroscopy and dynamic contrast-enhanced MPR images obtained at multi– detector row CT after air and water distention of the stomach can improve tumor detection rates as well as accuracy rates in T and N staging
3-D MDCT imaging data have to be interpreted in conjunction with axial and two-dimensional MPR for accurate staging of gastric cancer.
3-D imaging, with the same volume data obtained by spiral CT, especially by MDCT, can be repeatedly made with different reconstruction methods. It has a high accuracy, sensitivity and specificity in diagnosing and staging of gastric carcinoma.
In conclusion, MDCT is an important tool for diagnosing and staging gastric malignant disease, and is very important in the detection of the affected lymph node, extension into nearby organs and distant metastases.