2117. Quantitative Analysis of Dynamic CTA for the Detection of Endoleaks after Abdominal Aorta Aneurysm Endovascular Repair: A Feasibility Study
Authors * Denotes Presenting Author
  1. Rock Savage *; Medical University of South Carolina
  2. Tilman Emrich; Medical University of South Carolina
  3. Akos Varga-Szemes; Medical University of South Carolina
  4. Richard Bayer; Medical University of South Carolina
  5. U. Joseph Schoepf; Medical University of South Carolina
To assess the feasibility of quantitative analysis of dynamic computed tomography angiography (dCTA) for the detection of endoleaks in patients who underwent endovascular repair of abdominal aortic aneurysms (EVAR).

Materials and Methods:
Twenty patients scheduled for contrast-enhanced CT angiography (CTA) of the abdominal aorta post-EVAR were prospectively enrolled. All patients received a standard triphasic CTA protocol, followed by an additional dCTA. Based on a modified 5-point Likert scale, dCTA and dynamic CT perfusion (dCTP) were assessed for the detection of endoleaks. The ratio between the endoleak and aneurysm sac using blood flow for dCTP and Hounsfield units (HU) for dCTA was calculated.

19 patients (18 males, median age 74 years) were finally included. Nine endoleaks were detected in 7 patients using triphasic CTA as the reference standard. There was complete agreement for endoleak detection on a per-patient basis. Both dCTA and dCTP identified an additional endoleak in one patient. The diagnostic confidence using dCTP for detection of endoleaks was not significantly different to dCTA (5.0 [5 - 5] vs. 4.5 [4 - 5]; p = 0.11). dCTP demonstrated superior diagnostic confidence for endoleak exclusion compared to dCTA (1.0 [1 - 1] vs 1.5 [1.5 - 1.5]; p <0.01). The dCTP endoleak-index was significantly higher than the dCTA-index (18.5 [10.8 - 20.5] vs. 3.5 [5 - 2.7]; p = 0.02).

Quantitative dynamic computed tomography angiography imaging enables detection of endoleaks and demonstrates a higher detection rate in comparison to triphasic CTA.