Although direct evidence comparing CTA to other modalities in endoleak identification after endovascular thoracoabdominal aneurysm repair is lacking, multiple studies and meta-analyses have compared CTA with MRI and US for endoleak identification after EVAR for AAA [78,79,82,83]. A meta-analysis by Guo et al [82] in 2016 evaluated 3,853 patients after EVAR with paired scans of different modalities (CTA, MRA, US) within a 1-month period. In 2,346 paired CTA and duplex US scans, CTA identified 214 additional endoleaks not seen on duplex US (including 26 type I or type III endoleaks), whereas duplex US identified 77 additional endoleaks not seen on CTA (no type I or III endoleaks) [82]. In 1,694 paired CTA and MRA scans, CTA identified 2 additional endoleaks, whereas MRA identified 42 additional endoleaks [82]. A subsequent meta-analysis in 2018 by Zaiem et al [84] also noted that MRI identified more endoleaks than CTA. These findings suggest higher sensitivity of MRI to detect endoleaks, although the authors caution that the increased endoleaks identified could represent false-positive findings or endoleaks that are not clinically important [84]. CTA Chest and Abdomen With IV Contrast Compared with CTA of the chest, abdomen, and pelvis, evaluation of the chest and abdomen only without imaging of the pelvis may fail to detect changing or new pathology in the pelvic vasculature that could require additional intervention. MRA Chest, Abdomen, and Pelvis Without and With IV Contrast The spatial resolution of MRA is less than that of CTA, but the ability to detect branch vessel complications, endoleaks, stent graft complication, or infection has established MRA as an effective modality for imaging after endovascular repair, particularly for nitinol stent grafts, which have reduced susceptibility artifact.
Thoracoabdominal Aneurysm or Dissection Treatment Planning and Follow Up. Although direct evidence comparing CTA to other modalities in endoleak identification after endovascular thoracoabdominal aneurysm repair is lacking, multiple studies and meta-analyses have compared CTA with MRI and US for endoleak identification after EVAR for AAA [78,79,82,83]. A meta-analysis by Guo et al [82] in 2016 evaluated 3,853 patients after EVAR with paired scans of different modalities (CTA, MRA, US) within a 1-month period. In 2,346 paired CTA and duplex US scans, CTA identified 214 additional endoleaks not seen on duplex US (including 26 type I or type III endoleaks), whereas duplex US identified 77 additional endoleaks not seen on CTA (no type I or III endoleaks) [82]. In 1,694 paired CTA and MRA scans, CTA identified 2 additional endoleaks, whereas MRA identified 42 additional endoleaks [82]. A subsequent meta-analysis in 2018 by Zaiem et al [84] also noted that MRI identified more endoleaks than CTA. These findings suggest higher sensitivity of MRI to detect endoleaks, although the authors caution that the increased endoleaks identified could represent false-positive findings or endoleaks that are not clinically important [84]. CTA Chest and Abdomen With IV Contrast Compared with CTA of the chest, abdomen, and pelvis, evaluation of the chest and abdomen only without imaging of the pelvis may fail to detect changing or new pathology in the pelvic vasculature that could require additional intervention. MRA Chest, Abdomen, and Pelvis Without and With IV Contrast The spatial resolution of MRA is less than that of CTA, but the ability to detect branch vessel complications, endoleaks, stent graft complication, or infection has established MRA as an effective modality for imaging after endovascular repair, particularly for nitinol stent grafts, which have reduced susceptibility artifact.