Optimal window width and center level settings in 256-slice spiral CT diagnosis of costal cartilage fracture / 中国医学影像技术

Objective To investigate the optimal window level and center level settings in the diagnosis of costal cartilage fracture with 256-slice spiral CT through ROC analysis. Methods Thirty patients with suspected costal cartilage fractures underwent 256-slices chest spirals CT scaning. CT value of costal cartilage was measured by three experienced radiologists. The soft copy images of three kinds of window level and window width (-100 HU/1120 HU, 100 HU/1120 HU, 300 HU/1120 HU) were analyzed independently in PACS with dual-blind method, and the diagnosis results were taken ROC analysis with SPSS 16.0 software. The diagnostic accuracy of three physicians were evaluated and compared according to the area under the ROC curve (Az). Results A total of 8 patients of costal cartilage fractures were confirmed by CT diagnosis combined with clinical follow-up. The mean CT value of 30 patients was (98.78±32.86) HU. The area under the ROC curve with the window level and center level settings of (100 HU/1120 HU) were bigger than that of other window level and window width (P=0.045,P=0.002). Kappa identity test showed that there was a powerful conformability between the diagnostic results of three physicians. Conclusion 256-slice spiral CT is a good way for the diagnosis of costal cartilage fractures with suitable window level and center level settings.

Way of DIB Derived from DICOM Medical Image File / 中国医学物理学杂志

Objective: According to clinical investigation, analysis on the storage format of DICOM3.0 medical images files and displaying them is the basis of medical image processing. It is very important for medical imaging technology. Methods: Firstly, with the DICOM standard, the format of the medical images is studied, mostly the format of the information header and data element. Then the DIB display of the DICOM images in Windows platform is put forward, using linear window-transformation. Results: It is successfully realized the display of CT、MR images. With the manual window-transformation, the displaying would be better. Conclusion: As the results show, the method studied in the paper can preferably realize the display of the DICOM medical images, meeting certain clinical needs, and laying a foundation for the following study.

The selection of window width and level for measuring the airway dimensions with spiral CT scan: an experimental study in Japanese white big-ear rabbits / 介入放射学杂志

Objective To investigate the optimal window width and window level for measuring the airway dimensions with spiral CT scan in Japanese white big-ear rabbits so as to lay the foundation for airway stenting in animal experiments. Methods Multi-slice spiral CT scanning of cervico-thoracic region was performed in 30 healthy adult Japanese white big-ear rabbits, the anteroposterior and transversal diameter of the thoracic trachea, the anteroposterior diameter of the right and left bronchus were measured with lung window, mediastinum window and special fat window separately. The revealing rate of the tracheal wall and the measuring results in different windows and levels were recorded and compared with the anatomical data. The differences of the relevant data were statistically analyzed. Results With lung window, the tracheal wall was well demonstrated, but the relevant data were smaller than that with mediastinum window. With mediastinum window, the data were bigger and the tracheal wall border appeared blurred. The results obtained with fat window were close to the actual anatomical data. Conclusion For accurately measuring the anteroposterior and transversal diameter of the thoracic trachea in Japanese white big-ear rabbits with multi-slice spiral CT scan, fat window should be adopted, which is helpful for the preparation of tracheal and bronchial stents.