Thoracic aortic stent graft: comparison of contrast-enhanced MR angiography and CT angiography in the follow-up: initial results.
The objective of this study was to compare contrast-enhanced magnetic resonance angiography (CE MRA) and multislice computed tomographic angiography (MS CTA) in the follow-up of thoracic stent-graft placement. The CE MRA and MS CTA were performed following nitinol stent-graft treatment due to thoracic aneurysm ( n=4), intramural bleeding ( n=2) and type-B aortic dissection ( n=5). Corresponding evaluation of arterial-phase imaging characteristics focused on the stent-graft morphology and leakage assessment. Stent-graft and aneurysm extensions were comparable between both techniques. Complete exclusion (aneurysm, n=4; dissection, n=2) was assessed with high confidence with CE MRA and MS CTA. Incomplete exclusion (intramural bleeding, n=2; dissection, n=3) was assigned to lower confidence scores on CE MRA compared with MS CTA. On CE MRA the stent-graft lumen demonstrated an inhomogeneous signal, the stent struts could not be assessed. The CE MRA can be used as alternative non-invasive imaging for follow-up of nitinol stent grafts. Arterial-phase leak assessment can be less evident in CE MRA compared with MS CTA studies; therefore, the use of late-phase imaging seems to be necessary. The diagnostic gap of stent-graft fracture evaluation using MRA may be filled with plain radiographs.
Weigel
Stefanie
S
Department of Clinical Radiology, University of Muenster, Albert-Schweitzer-Strasse 33, 48149 Muenster, Germany. weigels@uni-muenster.de
Tombach
Bernd
B
Maintz
David
D
Klotz
Stefan
S
Vestring
Thomas
T
Heindel
Walter
W
Fischbach
Roman
R
D000368:Aged; D000497:Alloys; D000784:Aortic Dissection / Q000473:pathology* / Q000628:therapy; D000792:Angiography / Q000379:methods; D017545:Aortic Aneurysm, Thoracic / Q000473:pathology* / Q000628:therapy; D019917:Blood Vessel Prosthesis Implantation; D003287:Contrast Media; D005260:Female; D005500:Follow-Up Studies; D005682:Gadolinium; D006801:Humans; D021621:Imaging, Three-Dimensional; D007472:Iohexol / Q000031:analogs & derivatives*; D018810:Magnetic Resonance Angiography; D008297:Male; D009942:Organometallic Compounds; D015607:Stents; D014057:Tomography, X-Ray Computed
D000497:Alloys; D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol; C013616:nitinol; D007472:Iohexol; C038192:iopromide; D005682:Gadolinium