Dual-energy computed tomography imaging of the aorta after endovascular repair: potential for decreasing radiation dose

Congress:

EuroSafe Imaging 2018

Poster Number:

ESI-0037

Type:

EuroSafe Imaging

Keywords:

Aneurysms, Radiation safety, Diagnostic procedure, Audit and standards, CT-Angiography, Vascular, Radioprotection / Radiation dose, Interventional vascular, Action 2 - Clinical diagnostic reference levels (DRLs), Action 3 - Optimisation, diagnostic reference levels, image quality, Dosimetric comparison

Authors:

M. A. Fink, A. Steuwe, M. Cattelaens, L. Born, W. Stiller, H. U. Kauczor, F. Rengier

DOI:

10.1594/esi2018/ESI-0037

DOI-Link:

https://dx.doi.org/10.1594/esi2018/ESI-0037

Fig. 1: Surveillance strategy with optimized DECT protocol for patient monitoring after...

Fig. 2: Dual-energy postprocessing options. For the weighted average image a weighting...

Fig. 3: 1-year follow-up CT of a patient after abdominal EVAR. (A) Real noncontrast...

Fig. 4: 2-year follow-up CT of a patient treated with a Nellix® EndoVascular Aneurysm...

Background/introduction

Endovascular aortic repair (EVAR) has become an accepted and to date widely used minimally invasive alternative for the treatment of thoracic and abdominal aortic pathologies including aortic aneurysms, penetrating aortic ulcers and aortic dissections [1,2]. Imaging plays a crucial role both for preinterventional planning and for postinterventional follow-up. In the postinterventional setting, imaging aims at confirming treatment success and detecting potential complications. Complications of EVAR include endoleaks, endograft migration, endograft collapse, stent thrombosis and perigraft fistula formation [3]. Endoleaks represent the most common complication after...

Description of activity and work performed

To date, the CTA based follow-up after EVAR has been regularly preformed as a triphasic examination using single-energy technique. This triphasic protocol usually includes a non-contrast scan limited to the region of the stent graft, an arterial scan covering the abdominal aorta down to the groin and as indicated also the thoracic aorta, and a delayed phase again limited to the region of the stent graft typically acquired 60-70 s after contrast media injection. Depending on the postinterventional result and the occurrence of complications, such...

Conclusion and recommendations

Patients who undergo long-term imaging surveillance after EVAR are exposed to high cumulative radiation doses over time. To decrease life-time radiation exposure, dual-energy based CTA offers a promising alternative to the traditional triphasic imaging for these patients. Here, we illustrated an optimised biphasic dual-energy CT protocol reducing the radiation exposure during follow-up examinations by about 30%.

Personal/organisational information

Diagnostic and Interventional Radiology, University Hospital Heidelberg, Heidelberg, Germany

References

[1] United Kingdom EVAR Trial Investigators, Greenhalgh RM, Brown LC, Powell JT, Thompson SG, Epstein D, et al. Endovascular versus open repair of abdominal aortic aneurysm. N Engl J Med 2010;362:1863–71. doi:10.1056/NEJMoa0909305. [2] Schermerhorn ML, O'Malley AJ, Jhaveri A, Cotterill P, Pomposelli F, Landon BE. Endovascular vs. open repair of abdominal aortic aneurysms in the Medicare population. N Engl J Med 2008;358:464–74. doi:10.1056/NEJMoa0707348. [3] Mita T, Arita T, Matsunaga N, Furukawa M, Zempo N, Esato K, et al. Complications of endovascular repair for thoracic and...