Zhipeng Gao BEng, Presenter: Nothing to Disclose

Xiaoyi Ren, Abstract Co-Author: Nothing to Disclose

Xiaonan Cui, Abstract Co-Author: Nothing to Disclose

Donghua Meng, Abstract Co-Author: Nothing to Disclose

Jun Wang, Abstract Co-Author: Nothing to Disclose

Zhao Xiang Ye, Abstract Co-Author: Nothing to Disclose

We can obviously find that the use of the 100 kVp protocol for chest CT substantially improved vascular enhancement with 20% reduction in the radiation dose, even though IOCM (270 mgI/mL) was 10% less iodine than LOCM (300 mgI/mL), 

Over the last decade, the use of CT has increased dramatically in clinical examination. There has been growing interest in decreasing the radiation dose during chest CT examinations, since CT examination has the potential risks of radiation-induced carcinogenesis. At the same time, CIN is closely related to hospital acquired acute renal failure.

Vascular enhancement was significantly higher in 100 kVp protocol (group C: 204.9±32.4HUand group D:188.7±26.0HU) than 120 kVp protocol (group A: 172.1±24.4HU and group B:155.4±21.7HU). In addition, ED was lower in 100 kVp protocol (group C: 3.9±0.6 mSv and group D: 3.8±0.74 mSv) than 120 kVp protocol (group A: 4.8±1.3 mSv and group B: 5.0±1.2 mSv). The subjective degree of image quality and CNR was not significantly different among the four groups. 

In this study, ED was 20% lower in 100 kVp protocol than 120 kVp. The ED of Group D (100 kVp and 270 mgI/mL setting) was 3.8±0.74 mSv which was approximately the natural ambient radiation exposure.The application of lower tube voltage in CT increases the photoelectric effect, leading to a higher mean attenuation value of iodine. Vascular enhancement was significantly higher in 100 kVp (group C: 204.9±32.4HU and group D:188.7±26.0HU) than 120 kVp  (group A: 172.1±24.4HU and group B:155.4±21.7HU). The vascular enhancement of group D(100 kVp with IOCM setting) was 188.7±26.0HU, just approximated the general setting group A (120 kVp with LOCM setting). We used a weight-based adjustment of a combined modulation type of automatic exposure control technique to increased the tube current-time product (reference mAs) in the 100 kVp protocol to compensate for the increased image noise .In the objective and subjective image analyses of the image study, the image noise of the 100 kVp protocol was not significantly different from that of the 120 kVp protocol. In addition, The subjective degree of image quality and CNR was not significantly different among the four groups.  

Gao, Z, Ren, X, Cui, X, Meng, D, Wang, J, Ye, Z, Low Tube Voltage (100 kVp) Setting in Enhanced Chest CT: Improved Vessel Enhancement and Simultaneous Decreased Radiation Dose and Iodine Dose.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14004296.html