Peak systolic velocity ratio for evaluation of internal carotid artery stenosis correlated with plaque morphology: substudy results of the ANTIQUE study

BackgroundAccurate assessment of carotid stenosis severity is important for proper patient management. The present study aimed to compare the evaluation of carotid stenosis severity using four duplex sonography (DUS) measurements, including peak systolic velocity (PSV), PSV ratio in stenosis and distal to stenosis (PSVICA/ICA ratio), end-diastolic velocity (EDV), and B-mode, with computed tomography angiography (CTA), and to evaluate the impact of plaque morphology on correlation between DUS and CTA.MethodsConsecutive patients with carotid stenosis of ≥40% examined using DUS and CTA were included. Plaque morphology was also determined using magnetic resonance imaging. Spearman’s correlation and Kendall’s rank correlation were used to evaluate the results.ResultsA total of 143 cases of internal carotid artery stenosis of ≥40% based on DUS were analyzed. The PSVICA/ICA ratio showed the highest correlation [Spearman’s correlation r = 0.576) with CTA, followed by PSV (r = 0.526), B-mode measurement (r = 0.482), and EDV (r = 0.441; p < 0.001 in all cases]. The worst correlation was found for PSV when the plaque was calcified (r = 0.238), whereas EDV showed a higher correlation (r = 0.523). Correlations of B-mode measurement were superior for plaques with smooth surface (r = 0.677), while the PSVICA/ICA ratio showed the highest correlation in stenoses with irregular (r = 0.373) or ulcerated (r = 0.382) surfaces, as well as lipid (r = 0.406), fibrous (r = 0.461), and mixed (r = 0.403; p < 0.01 in all cases) plaques. Nevertheless, differences between the mentioned correlations were not statistically significant (p > 0.05 in all cases).ConclusionPSV, PSVICA/ICA ratio, EDV, and B-mode measurements showed comparable correlations with CTA in evaluation of carotid artery stenosis based on their correlation with CTA results. Heavy calcifications and plaque surface irregularity or ulceration negatively influenced the measurement accuracy

Policy sequencing for early-stage transition dynamics – a process model and comparative case study in the water sector

Sustainability scholars increasingly recognize that policy mixes can positively impact socio-technical transitions. However, the temporal dimension of policy interventions remains under-researched, especially in the context of early transition dynamics that typically emerge in niche contexts. In this article, we explore how policy sequencing can play a key role in supporting the scaling-up of early-stage transition dynamics to drive wider system change. We contribute to transition research by proposing a process model for analyzing policy sequences by focusing on the interplay between policy instruments and institutional barriers. We conceptualize two ideal-type policy sequencing patterns - strategic and reactive - which we illustrate with empirical examples from early transition dynamics in the urban water sector of San Francisco (United States) and Sant Cugat del Vallès (Spain). Applying the process model to these case studies reveals how different sequences of policy (instrument) mixes can assist in overcoming institutional barriers, thus supporting transition trajectories

Policy sequencing for early-stage transition dynamics – A process model and comparative case study in the water sector

Sustainability scholars increasingly recognize that policy mixes can positively impact socio-technical transitions. However, the temporal dimension of policy interventions remains under-researched, especially in the context of early transition dynamics that typically emerge in niche contexts. In this article, we explore how policy sequencing can play a key role in supporting the scaling-up of early-stage transition dynamics to drive wider system change. We contribute to transition research by proposing a process model for analyzing policy sequences by focusing on the interplay between policy instruments and institutional barriers. We conceptualize two ideal-type policy sequencing patterns - strategic and reactive - which we illustrate with empirical examples from early transition dynamics in the urban water sector of San Francisco (United States) and Sant Cugat del Vallès (Spain). Applying the process model to these case studies reveals how different sequences of policy (instrument) mixes can assist in overcoming institutional barriers, thus supporting transition trajectories.ISSN:2210-422