Assessment of normal and atherosclerotic arterial wall thickness with an intravascular ultrasound imaging catheter

Avaliação tardia de endopróteses coronarianas com sirolimus: comparação da tomografia computadorizada por múltiplos detectores com a angiografia quantitativa e o ultra-som intracoronariano

“…However, potential limitations to the kind of analysis mentioned in this study and even in investigations using more up-to-date equipment 13,14 make it clear that the routine use of multidetector tomography is not recommended for noninvasive follow-up of stent implantation, especially nondrugeluting stents.…”

“…Nevertheless, our findings are representative of the time in which the study was carried out and prompt similar trials when new equipment capable of rendering 64 images per cycle becomes available. Either way, despite claiming that MDCT scanners that generate 40 images per cycle may be useful for clinical use, the study by Gaspar et al produced only reasonable results using these systems, which had sensitivity of 88.9%, specificity of 80.6%, negative predictive power of 97.4%, and positive predictive power as low as 47.1% 13 . The difficulties faced by computed tomography regarding noninvasive analysis of stents are well-characterized in the study by Maintz, who analyzed 68 different coronary stents in a CT scanner capable of obtaining 64 images per cycle 14 .…”

“…Recent studies using multidetector technology equipped with 40 to 64 detectors still reported limitations in the diagnosis of in-stent restenosis, the results of which varied according to the type of prosthesis studied 13,14 . Although Gaspar et al have reported moderately satisfactory results using 40-slice CT scanners 13 , Mintz and associates, assessing coronary artery stents in vitro, determined that results depend on the specific model of the prosthesis being evaluated 14 . On the other hand, the presence of neointimal hyperplasia may represent a complicating factor for analysis of coronary stents late results by means of computed tomography.…”

Intravascular ultrasound imaging following balloon angioplasty

“…Several studies have shown excellent correlations between the lumen cross-sectional area measured from ul- trasound images compared with direct measurements from histologic cross-sections [1,5,6,8,9]. In addition, an in vitro study using acrylamide casts of a phantom model has demonstrated that contrast angiography overestimates the true lumen cross-sectional area compared with intravascular ultrasound when the lumen is not elliptical but irregular experienced interventional angiographers are impressed by the huge amount of residual atheroma that remains at the site of balloon angioplasty.…”

Computer aided diagnosis of Coronary Artery Disease, Myocardial Infarction and carotid atherosclerosis using ultrasound images: A review

“…The catheter is inserted into an artery where the US sensor captures intravascular images. These images depict the morphology of both plaque and arterial wall [115]. IVUS can help to detect the presence and to determine the atherosclerosis composition in angiographically normal reference sites [116].…”