Reappearance of table's position in IVR-CT system

This paper reports on reappearance of the re-setup table's position by changing from angiographic mode into CT scanning mode or vice versa in IVR-CT system. Its reappearance was estimated by measuring errors of three directions (anterior-posterior, superior-inferior, right-left direction) from both of reference images and re-setup images. As the result, the error was within 1 mm in both anterior-posterior and superior-inferior direction, and was more than 10 mm in right-left direction. We believed that the former was the tolerable margin of error, but the latter was less favorable in clinical use. After close examination by a medical maker, it was found that our IVR-CT system had a deficiency in the right-left direction's structure: angiography and CT scanning were being performed on the same table. However, we could cope efficiently with the problem by changing a ROM that was a control part to lock a right-left center. We greatly demand an original-designed IVR-CT system that is well coordinated many useful modalities to medical manufacturers. (author)