| IntroductionJaw Bone Tumor is a common tumor of the oral and maxillofacial tumor. Because of their widely resource, complicated categorization, various organic conformation and structure, and diversification of clinical manifestation, mainly its diagnosis before operation depends on the technology of imaging detection. Though are there so many technology of imaging diagnosis, compared with the methods of usual imaging diagnosis currently, it is CT, especially SCT, that can get more accuracy of detection and location for jaw bone tumor. Because of its characters of extraordinary resolution of space and density, and its MPR and multi-aspect imaging, CT is used in diagnosis of jaw bone tumor widely. DSCT is the most advanced equipment of CT, its function of double energy scan develops original clinical application and study aspect. Then patients with jaw bone tumor were examined by DSCT in this study to assess the clinical application value of DSCT.Materials and Methods1. Research objectThe study included 30 patients whom were confirmed to suffer from jaw bone tumor by pathological examination after operation and whose preoperative examinations were performed on Siemens SOMATOM Definition multi-slice spiral computed tomography. According to the histology classify standard of oral and maxillofacial tumor by WHO, these cases were classified into odontogenic tumor and tumor-like lesion, non-odontogenic tumor and tumor-like lesion. According to the biological behavior these cases were classified into cyst, benign tumor and malignancy tumor. 2. Instrument and methodAll of the 30 patients with jaw bone tumor were examined with double energy scan of DSCT under the condition of 140kv/70mAs and 80kv/297mAs, 1.0mm each slice, pitch 1.0 mm, non-interval continuous axial view scan, with the extent from supraobital arch to submaxilla lower margin, soft tissue window (W350,L40) and bone window (W2700,L350) . The primary data were transferred to Siemens MMWP workstation and post-operation with 3-dimension reconstruction and reformation techniques.3. Image processing, image analysis and data measure(1)The primary data were transferred to Siemens MMWP workstation and post-operation with 3-dimension reconstruction and reformation techniques including MPR, VR and CPR in the diagnosis of jaw bone tumor. When image reconstruction, two group imaging of 140kv and 80kv were kept with the same parameter, including soft tissue window and bone window.(2)The images were read and analyzed by two senior radiologists at workstation screen independently. They evaluated the relationship display of tumor and surrounding tissue with different scanning conditions, including the relationship display of tumor and surrounding soft tissue under soft tissue window, the relationship display of tumor and surrounding bone tissue and the relationship display of tumor and teeth under bone window. The estimate standard of section image: 2, the detail of structure can be recognized clear, and the neighborhood can be judged straight; 1, the detail of structure can be recognized, but not clear or the neighborhood could not judged straight; 0, the structure could not be seen. The full marks were 60 score, and the last score was the arithmetic mean by two radiologists.(3)Measure the big size of tumor in the image of axial view, which image displayed the large tumor in sight. Choose ROI in the best image of tumor(except peripheral edema, blood vessel, necrosis, bleed, calcify and bone), in which measure the CT value of tumor and other side masseter thrice, the last score was the arithmetic mean.4. Statistics analysis (l)Use SPSS13.0 software to analyze the data of display difference of tumor and surrounding tissue in different voltage conditions with Wilcoxon Signed Rank Test. All data were divided into two group, A group (140kv) and B group (80kv). The size of test:α= 0. 05.(2)Use SPSS 13.0 software to analyze the data of tumor size difference in different voltage conditions with Paired-Samples T Test. All data were divided into two group , A group (140kv) and B group (80kv). The size of test:α= 0. 05.(3)Use SPSS13.0 software to analyze the data of the CT value of tumor and other side masseter with Paired-Samples T Test. All data were divided into two group, A group (tumor) and B group (masseter). The size of test:α= 0. 05.ResultsIt is significant that the difference between the data of display difference of tumor and surrounding tissue in different voltage conditions. It is significant that the difference between the data of tumor size difference in different voltage conditions. It is significant that the difference between the data of the CT value of tumor and other side masseter.ConclusionDSCT is of great clinical application value in the diagnosis of jaw bone tumor because of its extraordinary resolution of space and density. Use the image of different energy scan, it may display the relationship display of tumor and surrounding tissue well, display the relationship of tumor and surrounding soft tissue under low voltage condition well while display the relationship of tumor and surrounding bone tissue and the relationship display of tumor and teeth under high voltage well. |
