Coronary stent assessment on multidetector computed tomography: source and predictors of image distortion.
Level 3 - non-randomized controlled study
Observational comparative diagnostic imaging study comparing MDCT measurements against quantitative coronary angiography.
PubMed 17707094 · doi:10.1016/j.ijcard.2007.04.097
What was done
Researchers evaluated 151 non-opacified coronary stents in 89 patients (81% men, mean age 65±10 years) imaged with a 40-slice multidetector computed tomography (MDCT) scanner. Stent dimensions and image distortion on MDCT were compared across different stent types, sizes, and orientations against quantitative coronary angiography (QCA) measurements obtained immediately post-implantation and manufacturer data.
What was found
Stent image quality on MDCT was good for 107 stents (71%), moderate for 38 (25%), and poor for 6 (4%), with 2 (<1%) unassessable. Blooming artifact led to a mean MDCT luminal inner diameter 30±14% smaller than QCA (2.0±0.5 mm vs 2.9±0.3 mm, p<0.001) and a mean outer diameter 31±14% larger than QCA (3.8±0.5 mm vs 2.9±0.3 mm, p<0.001). Luminal diameter was unrelated to strut thickness or stented vessel, but was significantly smaller for vertically oriented stents (p=0.017), cobalt alloy compared to stainless steel (p=0.011), and varied by stent type (p=0.006).
Why it matters
This study quantifies the degree of artificial lumen reduction caused by MDCT blooming artifacts, highlighting specific stent materials and orientations that hinder accurate non-invasive assessment of in-stent restenosis.
Limits
The study is limited to 40-slice MDCT technology, which has lower spatial resolution than newer generation scanners. The sample was predominantly male (81%), and the abstract does not report clinical outcomes or diagnostic accuracy for actual restenosis detection.
Cited by
- supports CT coronary angiography causes blooming artifact around preexisting coronary stents, preventing clear visualization inside the stent.