The feasibility of a low iodine concentration contrast medium (140 mg/mL) during low-tube-voltage aortic CT angiography

Congress:

ECR 2020

Poster Number:

C-08958

Type:

Scientific Exhibit

Keywords:

Case-control study, Retrospective, Image verification, Contrast agent-intravenous, CT-Angiography, CT, Vascular, Contrast agents, Arteries / Aorta, Performed at one institution

Authors:

Y. Ohka¹, K. Takegami¹, S. Kudomi¹, T. uehara¹, S. Tokurei², M. Okada ¹, T. Nomura¹, K. miyoshi¹; ¹Yamaguchi/JP, ²Fukuoka/JP

DOI:

10.26044/ecr2020/C-08958

DOI-Link:

https://dx.doi.org/10.26044/ecr2020/C-08958

Fig. 2: Two injection protocols for aortic CTA used in this study. In the 70-kV CTA,...

Fig. 3: Measurement regions for image analysis; (a) The CT values and SNR were measured...

Fig. 6: The CT values and the SNR plotted as a function of body weight measured at the...

Fig. 7: Residual CM at the subclavian vein. The low-concentrated CM (140 mg/mL)...

Purpose

During contrast enhanced CT examinations, the amount of an iodine contrast medium (CM) should be optimized to reduce the risk of the kidney disease [1,2]. A lot of researchers plan to improve injection protocols and scan conditions using various techniques. In our study, we focused our attention on the combination of a low tube voltage CT (70-kV) and a CM with the low iodine concentration (140 mg/mL). A CT value derived in the scan of 70-kV shows two times more than that of 120-kV, and...

Methods and materials

This retrospective study was approved by our institutional review board. We selected 150 patients who underwent aortic CTA using a dual-source scanner (SOMATOM Force, Siemens Healthineers) between 19th July and 31st October 2018. Body weight, volume CT dose index (CTDIvol) values indicated in the dose report of the CT system, and injection conditions were reviewed for all patients. During the period, 100 patients underwent standard-voltage CTA with standard iodine dose as the reference protocol (protocol 1), and the remaining 50 patients underwent 70-kV aortic CTA...

Results

Fig. 4 summarizes comparisons of body weight, iodine doses, injection rates, duration times, CTDIvol values, averaged CT values, SD and SNR between standard and 70-kV aortic CTA. Fig. 5 indicated the relationships between the body weight and the CTDIvol. were consistent between the standard CTA protocol and 70-kV aortic CTA with low-concentration CM of 140 mg/mL. The averaged CT values at the aortic arch and descending aorta were 455.3±52.0 and 448.2±53.3 HU in the standard aortic CTA and 435.2±47.4 and 426.6±45.4 HU in 70-kV aortic...

Conclusion

Compared with the standard aortic CTA, the combination protocol of 70-kV and low-concentration CM of 140 mg/mL allowed us to reduce iodine amount by 50% while maintaining contrast enhancement. Additionally, the low-concentration CM of 140 mg/mL was effective to reduce the residual CM at the subclavian vein significantly. Further verification of application for other contrast-enhanced CT will be needed for more practical examinations.

Personal information and conflict of interest

Yurina Ohka R.T. Yamaguchi University Hospital, Japan [email protected] We have nothing to desclose.

References

[1] Maurice Laville and Laurent Juillard. Contrast-induced acute kidney injury: how should at-risk patients be identified and managed? J. Nephrol. 2010;23(04):387-398. [2] Connie L. Manske, J. Michael Sprafka, John T. Strony, et al. Contrast nephropathy in azotemic diabetic patients undergoing coronary angiography. Am. J. Med. 1990;89(5):615-620. [3] Kyongtae T. Bae. Intravenous contrast medium administration and scan timing at CT: Considerations and approaches. Radiology. 2010;256(1):32-61. [4] Michael M. Lell, Gregor Jost, Jahannes Georg Korporaal et al. Optimizing contrast media injection protocols in state-of-the art computed tomography...