The computer aided three dimensional reconstruction can provide information regarding the tumor scope and anatomy characteristics, thereby assisting in risk assessment and surgical plan. The computer aided three-dimensional reconstruction can provide information for diagnosing and treating local advanced thyroid cancer. To begin, obtain plain and enhanced CT images of the patients using a 256 layer spiral CT system.
Obtain the scan data from the CT system in DICOM format. Then import the data into the 3D visualization software by clicking on the Open button. If the data contains image noise, process the data for Gaussian smoothing by first selecting the data with the right mouse button, and then clicking on the Gaussian smoothing button.
Next, select the tab Different Models in the software according to the structure to be reconstructed, such as blood vessels or the skin. Set the color, maximum threshold and minimum threshold. Adjust the upper and lower thresholds based on the observed preview effect.
Repeat the procedure to obtain the segmentation data of other structures such as the bones. Click on the calculation button to complete the preliminary 3D model reconstruction. Then use the smoothing algorithm button to optimize the segmented data and ensure that the reconstructed sawtooth edges match the real tissue.
Then use the one click navigation button to locate the 2D and 3D images and determine whether the segmentation effect was accurate. Use the pen or brush tool to fix the incorrect layers. For preoperative evaluation, view the 3D model and evaluate the tumor volume and location.
Using the magnification, rotation, tissue transparency and separation functions, evaluate the relationships between the tumor and the adjacent tissues using a combination of various structures. In the case of a 50 year old patient with thyroid carcinoma, initial evaluation using CT angiography suggested that a large number of vessels were involved in the tumor. Using CT data, the surgical team completed computer-aided 3D modeling of the tumor.
Evaluation of the 3D model revealed the relationships between the tumor and the blood vessels, and further operative procedures were determined. It's important to check whether the three dimensional images is consistent with the CT images for successful reconstruction.