Table 2 Aortic infections: CT, MR and 18 F FDG-PET/CT imaging features, advantages and disadvantages

AV endocarditis

[20–22, 25, 26]

• Leaflet vegetation

• Leaflet perforation

• Perivalvular abscess

• IFB extension

• Pseudoaneurysm

• Vegetations >2 mm oscillating & complications

• Increased radiation dose with multiphase CT

• Functional assessment

• Lower spatial resolution than CT

• Flow-related artefacts

• Distal septic emboli

• Low sensitivity (66 %)

PV endocarditis

[36, 44–46]

• Valve dehiscence

• Perivalvular abscess

• Pseudoaneurysm

• Valve dehiscence on multiphase CT

• Increased radiation dose with multiphase CT

• Prosthesis-related artefacts

• Functional assessment

• Prosthesis-related artefacts

• Flow-related artefacts

• Increases specificity of modified Duke criteria to 91–97 %

• Distal septic emboli

• Not evaluable until >90 days post-insertion

Infectious aortitis

[47, 49, 57]

• Aortic wall thickening (often crescentic) ± enhancement

• Pockets of gas

• Adjacent fat stranding & fluid

• Demonstrates gas & periaortic inflammation

• Aortic mural enhancement can be hard to appreciate

• Superior aortic wall assessment

• Sensitive for periaortic abscess

• Gas & surrounding inflammatory changes harder to define

• Small series reports sensitivity of 100 %

• Low spatial resolution

Mycotic aneurysm

[47, 49, 54, 59]

• Saccular aneurysm

• Rapid growth in aneurysm size

• Adjacent fat stranding & fluid

• Periaortic inflammation easily demonstrated

• Increased radiation if multiple sequential studies

• Lack of radiation in sequential studies

• Peri-aneurysm inflammation less well defined than on CT

• Can distinguish infected from bland aneurysm

• Low spatial resolution

Aortic graft infection

[44, 45, 49, 92, 94–96]

• Pseudoaneurysm

• Perigraft soft tissue stranding

• Perigraft fluid & gas

• Aortoenteric fistula

• Periaortic inflammation is clearly visible

• Can demonstrate fistula

• Increased radiation dose with multiphasic CT

• Can distinguish perigraft fluid from haematoma

• Prosthesis-related artefacts

• Reported sensitivity of 89–100 %

• False positives in early postoperative phase