Multi-slice spiral CT imaging of gastric cancer, spiral CT (multi-sliceCT, MSCT) represents a new recent revolution in CT technology. Dual-detector system in the early 90s in the 20th century, in 1998 detector array 4 rows come out, since 2001, 8 row, 10 row, 16 row 64 row CT have now come out, and quickly accepted by the academic radiology , installed the speed curve is exponential.
Multi-slice spiral CT system equipped with two or more parallel detectors, the accelerated speed of rotation so that the performance of multi-CT system has been further improved. 4-slice spiral CT are better than single-detector CT increased by 8 times, 16 rows can be up to 25 times. The traditional multi-CT axial CT images alone evolved into a true three-dimensional imaging, available in any direction on the fault, and three-dimensional volume data to achieve a good show. Multi-slice spiral CT, the thinnest slice thickness up to 0.5mm, the basic to the isotropic. Spiral CT reduces scanning time and reduce the layer alignment, and thus increases the scanning range. As a result of low dose X ray scanning technology to reduce the patients received radiation dose.
Spiral CT also reduced the overlap of information between all levels, thus improving the sampling rate, and noise can be reduced by 30%, and improved image SNR. CT scan compared with conventional single-layer, multi-slice spiral CT can reduce the use of contrast agents, contrast dosage can be reduced about 60%. Equipped with multi-slice spiral CT in oncology-specific software package, can be a variety of advanced multi-slice spiral CT shows three-dimensional post-processing features, four-dimensional morphological information as well as functional information directly with the tumor radiation treatment planning system matching, for irradiation Wild design, develop dose distribution and treatment programs, but also for the treatment of post-treatment quantitative and qualitative comparison. The imaging information more directly applied to oncology.
Spiral CT of gastric cancer imaging of, for these many advantages, multi-slice spiral CT for the CT greatly stimulated people's interest in gastrointestinal applications, in gastric cancer diagnosis are all ages. CT volume caused by MSCT data, interactive and dynamic 3D image display to the display of gastric lesions clearer image. As slice thickness reduction, so that the detection rate of early gastric cancer can be found in the stomach cavity of the uplift or depression of 0.5mm lesions, while progress in the detection and staging of gastric cancer and more accurate.
Three-dimensional reconstruction can be displayed at any angle around the lesion and violations, lymph node metastasis and distant metastasis, high accuracy positioning of lesions in the axial images, scan speed, high image quality, 3D images obtained more clearly on the disease and more accurate positioning; virtual endoscopy function not only able to detect cavity lesions, cavity lesions on the display can achieve comparable results with endoscopy; it can be combined with the crown, sagittal reconstructed image observed lesions, and can be combined with PACS workstation observed routes movie playback from a different angle and direction of observation of lesions, to achieve the so-called four-dimensional imaging.
Since the acceleration of scanning, MSCT to gastric dynamic enhanced MRI is more accurate, the stomach can really complete the simple arterial and venous phase scanning, resulting in enhancement pattern of lesions more information, a clear indication of the stomach and tumor blood vessel blood vessels, the tumor's blood supply, etc., to include up to 5, including unenhanced scans were plain ,20-25s in the arterial phase, 50s ,90-120s vein of interstitial and 5min of delay period. Three-dimensional reconstruction from raw data can be clearly shown by the gastric feeding artery and draining vein week.
Multi-slice spiral CT imaging of gastric cancer, for patients with known gastric lesions, the general 4X1.0mm collimator settings, can produce a 1mm 1.25mm thickness and reconstruction interval image. Overlap caused by three-dimensional imaging can improve the quality. Use this setting to scan from the top of the right side of Confucianism Kawasaki leap takes 20s. Although you can use the 1.25mm thickness for three-dimensional reconstruction of the data collected can also be used to reconstruct 3-5mm conventional image, to facilitate the film's print and workstations browse the images, reflecting the flexibility of MSCT imaging. Based on the experience of postoperative gastric cancer usually 3mm thick CT review is sufficient.