Virtual Histology Intravascular Ultrasound Evaluation of Atherosclerotic Carotid Artery Stenosis: Time for Fully Quantitative Image Analysis

Imaging modality-dependent carotid stenosis severity variations against intravascular ultrasound as a reference: Carotid Artery intravasculaR Ultrasound Study (CARUS)

“…Other factors, such as cardiac output and arterial blood pressure/peripheral vascular resistance [ 53 ], contralateral carotid artery occlusion (or severe stenosis) and lesion length may affect DUS velocities. Our pilot analysis indicated that automated pullback of the IVUS catheter tends to be uneven at carotid bifurcations, precluding measurements of the lesion length [ 71 ]; a problem similar to the effect of movement artifacts raised previously by other investigators in coronary bifurcations [ 72 ]. In addition, in the carotids, there is also an additional, prominent, “jumping” of the IVUS probe, back-and-forth, with the heartbeat [ 71 ].…”

“…Our pilot analysis indicated that automated pullback of the IVUS catheter tends to be uneven at carotid bifurcations, precluding measurements of the lesion length [ 71 ]; a problem similar to the effect of movement artifacts raised previously by other investigators in coronary bifurcations [ 72 ]. In addition, in the carotids, there is also an additional, prominent, “jumping” of the IVUS probe, back-and-forth, with the heartbeat [ 71 ]. The role of contralateral carotid occlusion (if present) and the potential role of the lesion length on DUS flow velocities require further evaluation.…”

Transcoronary stem cell transfer and evolution of infarct-related artery atherosclerosis: evaluation with conventional and novel imaging techniques including Quantitative Virtual Histology (qVH)

“…Indeed, 87.5% of IVUS-identified lesions in this study could be detected with QCA (see Table III vs. Table II ). Importantly, our study applied not only a range of routinely available state-of-the-art techniques (such as conventional IVUS, “automatic” VH image analysis limited to quantification of the “total” per plaque cross-sectional area NC/FF/FT/Ca and prone to several fundamental analysis artefacts [ 29 , 30 , 55 ] and other constraints [ 56 ]) but also a novel algorithm of qVH evaluation [ 21 ]. Recently validated qVH algorithm [ 21 ], with its precise evaluation of fundamental plaque biophysics-based characteristics [ 23 , 24 ] ( Figure 1 ), has been presently introduced for the first time in a longitudinal clinical study use ( Figures 2 , 3 , Table IV ).…”

“…Further limitations of the conventional VH-IVUS analyses arise from inability to quantitatively discriminate artefacts [ 29 , 30 ], use of different TCFA definitions use across studies [ 22 , 48 , 56 , 63 ] as well as the “requirement” of the TCFA phenotype “presence” in 3 consecutive VH-IVUS frames” to determine the lesion as TCFA [ 23 ]. Because the radiofrequency image capture is triggered by the R have on ECG [ 22 ], the latter results in the dependence of TCFA identification on heart rate at the time of IVUS interrogation which is clearly flawed [ 55 ]. These limitations of conventional analysis lead to fragility of TCFA identification in over 40% coronary plaques getting labelled as a “TCFA” [ 56 ].…”

Commentary: Vertebral Artery Ostial Stenosis Stenting Technique

“…Finally, similar to the symptomatic carotid bifurcation stenosis, symptomatic VAOS is likely to be a "mixed bag" where different lesion subsets 26 may benefit from different lesion-specific procedural strategies that involve different stent types. 27,28 Indeed, highly symptomatic vertebral 29 or subclavian/vertebral bifurcation lesions have been treated with proximal protection and maximized (at that time) coverage of friable/thrombus-containing plaque material to minimize embolization to the brain with no significant ISR in the long run.…”