Accuracy of spiral CT in preoperative staging of gastric carcinoma: correlation with surgical and pathological findings.

OBJECTIVE: To assess the accuracy of spiral CT scan in the preoperative staging of gastric carcinoma by comparing it with surgical/pathological staging. MATERIAL AND METHOD: Twenty-eight patients with gastric carcinoma who underwent both preoperative CT scan and surgery were retrospectively studied for TNM classification. All CT scans were reviewed for tumor location, gastric wall thickness, tumor extension, N1 and N2 nodal involvement, and metastases to the liver, peritoneum and lung. RESULTS: Spiral CT staging was correct in 20 of 28 patients (71.4%). The preoperative CT scan had 96.1% sensitivity, 100% specificity and 96.4% accuracy for evaluating serosal invasion. The sensitivity, specificity and accuracy for assessing pathologic lymph node involvement were 73.1, 50.0 and 84.2 percent, respectively. In the present study, peritoneal metastasis could not be identified by CT but CT had 100% sensitivity for evaluating hepatic metastases. CONCLUSION: Spiral CT is a useful modality for preoperative staging of gastric carcinoma with high accuracy for evaluating serosal invasion and hepatic metastases.

Helical CT assessment on hilar cholangiocarcinoma: comparison value of arterial phase and portovenous phase correlation.

OBJECTIVE: To study the correlation between the findings of hilar cholangiocarcinoma in hepatic arterial phase and portal venous phase. Attention will focus on whether the arterial phase imaging shows more detail than portal phase imaging. MATERIAL AND METHOD: Descriptive study design with retrospective data collection in Srinagarind Hospital, Khon Kaen University. CT scans of the upper abdomen of 34 patients with pathologically proven hilar cholangiocarcinoma between 2002 and 2004 were reviewed for: (1) characteristic of the tumor; (2) adenopathy, (3) arterial involvement, (4) venous involvement, and (5) degree of biliary involvement on both the hepatic arterial and portal venous phases. RESULTS: The correlation was high for characteristics of the tumor, the tumor enhancement pattern, and detection of adenopathy, degree of biliary involvement, and arterial involvement, but low for portal venous involvement which the portal venous phase detected better than the hepatic arterial phase. CONCLUSION: In hilar type cholangiocarcinoma, the portal venous phase yielded the best findings. Furthermore, it showed all findings that were seen in the hepatic arterial phase. According to the present study, the authors suggest doing a pre-contrast study then a portal venous phase imaging for evaluation and diagnosis of hilar type cholangiocarcinoma. There is no necessity to perform hepatic arterial phase in hilar cholangiocarcinoma.

Multidetector-row CT of Malignant Biliary Obstruction / 대한소화기학회지

Multidetector-row computed tomography (MDCT) is useful for the evaluation of malignant biliary obstruction because it allows faster scanning, which decreases motion and breathing artifacts, as well as thinner collimation. In addition, MDCT leads to improved 3-dimensional assessment of vascular structures and biliary tree. The purpose of this pictorial essay is to introduce scanning techniques and image acquisition methods for the evaluation of malignant biliary obstruction and to highlight the unique display of diagnostic information by multiplanar reformations of the biliary tract with MDCT.

Applications of Multidetector-row CT for the Imaging Diagnosis of Liver Disease / 대한소화기학회지

Owing to the development of multidetector-row CT (MDCT), capability in the imaging diagnosis of liver disease has increased surprisingly. First, a marked decrease in scan duration of the liver enables us to select the accurate scan time optionally. Secondly, a marked decrease in slice thickness enables us to render isotropic and three-dimensional images completely. In this pictorial review, we described the optimal contrast enhancement of the liver on MDCT and its significance as well as the applications of isotropic and three-dimensional images obtained by MDCT.

Virtual CT Colonoscopy and Virtual CT Barium Enema using Multidetector-row CT / 대한소화기학회지

CT colonography is a promising technique that provides both multiplanar and endoluminal perspective of the air-filled, distended, cleaned colon. "Virtual colonoscopy" refers to computer-simulated 3D endoscopic visualization of the colonic mucosal surface. Unlike barium enema and conventional colonoscopy, CT colonography can give cross- sectional and endoluminal images of the colon and enables to image extracolic abnormality. CT colonography offers potential advantages over colonoscopy in that it causes little discomfort to the patient, and does not need sedation. It is more accurate in spatial location of lesions and creates no complication. To date, most studies assessing CT colonography have focused in technical development, less aggressive bowel preparation, and computer-aided diagnosis of polyp detection. In the future, CT colonography would be a diagnostic and screening tool for the colorectal polyp and cancer.

Multidetector-row CT of the Gastrointestinal Tract / 대한소화기학회지

Recently, the availability of multidetector-row CT (MDCT) and continuous refinement in three-dimensional (3D) imaging process have greatly expanded the role of CT in evaluating patients with gastrointestinal diseases. MDCT is the latest advancement in CT technology and is now more readily available. This imaging modality can offer full examination of the entire intestinal tract as well as powerful information about the bowel itself and its surrounding structures, which are inherent advantages of CT over conventional barium or optical endoscopic studies. In most cases, MDCT with various 3D technologies can make an easy, rapid, and accurate diagnosis by one-stop imaging, and enables to avoid other examinations. Therefore, knowledge and awareness of valuable clinical applications and proper scan technique of MDCT imaging is essential to achieve the diagnostic goal of one-step imaging.

Recent Progress in Abdominal CT Imaging / 대한소화기학회지

In this pictorial review, we introduce recent technical development of CT scanning in the imaging of the abdominal organs, namely, the gastrointestinal tract, colon, liver, biliary tract, and pancreas. With multidetector- row CT scanner, we can depict the abdominal organs by doing thin-section volumetric images and displaying the images in transverse axial, coronal, and sagittal plane reconstruction with isotropic images. We can see the interior of the abdomen directly as in the operating theatre. In addition, we can see the interior of the gastrointestinal tract as if we are flying through a tunnel.