• Purpose At present, it is difficult with patients with hypercalcification caused by dialysis to visualize blood vessels in the area of lower limb CTA due to the influence of calcification, and there are many cases in which it is impossible to recognize blood vessels. In view of this problem, we focused on material decomposition, an advantage of dual energy CT, in order to visualize blood vessels in case we face patients with hypercalcification. We actually performed imaging and examined it in order to decide...

• Method Imaging using dual energy was performed in patients with ASO (31 subjects). Eleven of these 31 subjects were patients that had been followed up, and from this examination on, the imaging method has been changed to the one using dual energy for them. Each image taken this way was reconstructed into CPR, MPR, VR, and MIP, and then they were compared and examined. Evaluation was performed visually by two radiologists and ten radiographers. Devices used •TOSHIBA Aquliion64 • SIEMENS SOMATOM Force The imaging...

Blood vessels, which could not be recognized due to the influence of calcification, could be recognized by the imaging method with dual energy when visual evaluation is done for images taken at this time and VR, MIP, MPR, and CPR reconstituted based on it. Extraction of peripheral blood vessels and collateral circulation was also better than the image in Figure (1.2.3.4.5). Also, he positional relationship of calcification within the blood vessel was well recognized visually if seen from CPR, MPR, etc.

From the above results, it can be said that material decomposition by means of dual energy is useful for CTA examination because it well extracts blood vessels, which would be otherwise unrecognizable due to calcification, etc. Additionally, since there is a possibility that dual energy can be used for other than CTA, we would like to continue to make use of the usefulness of dual energy in the future.

• Ohashi, Kazuya SIMENS Technical Report 01 CT technology which needs to be understood well - tube voltage settings - p. 6-7 • Hiwasa, Tsuyoshi Publication: MEDICAL VIEW Title: Current situation and prospects of dual energy CT - Toward next-generation standard CT - Implementation of true Dual Energy Imaging in Dual Source CT p. 435 – 439 Sommer, Wieand H., MD and Nikolau, Konsatantin, MD SIMENS Title: SOMATOM Sesionns the Difference in Computed Tomography Volume 23 p. 30