Department of Vascular and Endovascular Surgery, Flinders Medical Centre, Bedford Park, South Australia, Australia; College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia.
Department of Vascular and Endovascular Surgery, Flinders Medical Centre, Bedford Park, South Australia, Australia; College of Medicine and Public Health, Flinders University, Adelaide, South Australia, Australia.
J Vasc Surg. 2021 Aug;74(2):606-614.e1. doi: 10.1016/j.jvs.2020.12.108. Epub 2021 Feb 4.
Vascular micro-channels within chronic total occlusions (CTO) have been identified in histopathology and animal studies. They have been proposed as a potential path for achieving endovascular crossing via the lumen. There are currently no noninvasive means of imaging these structures. The aim of this study was to investigate whether contrast-enhanced ultrasound (CEUS) examination can identify micro-channels within CTO in humans.
CTO within the femoropopliteal arteries were imaged with CEUS examination in 38 patients. Segments containing micro-channels were identified and their length measured. The proportion of occlusion length containing micro-channels was assessed for each case. Micro-channel appearances including linear or tortuous configuration, crossing of occlusion caps, and connections to vasa vasorum were recorded.
The median CTO length was 17.0 cm (interquartile range [IQR], 6.9-27.9 cm) and median age of CTO was 12 months (IQR, 6-16 months). Micro-channels were identified in 92.1% of cases (35/38). The median length within a lesion containing micro-channels was 6.4 cm (IQR, 2.4-14.3 cm) and median proportion of CTO containing micro-channels was 47.9% (IQR, 1.7%-28.5%). A linear micro-channel configuration was seen in 84.2% of cases and a tortuous configuration was seen in 57.9% of cases. Micro-channel connections through the cap were seen in 50% (19/38 cases) and connections to the vasa vasorum in 71.1% (27/38 cases). No association was found between the proportion of each lesion containing micro-channels and CTO age, lesion length or calcification severity. There were no adverse effects related to contrast use.
CEUS can be used to detect micro-channels in CTO in human femoropopliteal arteries. This imaging technique is safe and minimally invasive and may represent a practical method for selection of occlusion crossing method. Further work is required to determine whether identification of micro-channels can be used to improve treatment decision-making and provide a better understanding of the natural history of femoropopliteal CTO.
在组织病理学和动物研究中已经发现慢性完全闭塞（CTO）内的血管微通道。它们被提议作为通过管腔实现血管内交叉的潜在途径。目前没有非侵入性的成像方法来显示这些结构。本研究旨在探讨对比增强超声（CEUS）检查是否能在人体内识别 CTO 内的微通道。
对 38 例股腘动脉 CTO 进行 CEUS 检查。识别包含微通道的节段并测量其长度。评估每个病例中闭塞长度包含微通道的比例。记录微通道的外观，包括线性或扭曲配置、闭塞帽的交叉以及与血管周围空间的连接。
CTO 的中位长度为 17.0cm（四分位间距[IQR]，6.9-27.9cm），CTO 的中位年龄为 12 个月（IQR，6-16 个月）。92.1%（35/38）的病例中识别到微通道。包含微通道的病变内的中位长度为 6.4cm（IQR，2.4-14.3cm），包含微通道的 CTO 的中位比例为 47.9%（IQR，1.7%-28.5%）。84.2%的病例中可见线性微通道形态，57.9%的病例中可见扭曲形态。微通道通过帽连接的情况见于 50%（38 例中有 19 例），与血管周围空间连接的情况见于 71.1%（38 例中有 27 例）。每个病变中包含微通道的比例与 CTO 年龄、病变长度或钙化严重程度之间无相关性。与造影剂使用相关的不良事件没有发生。
CEUS 可用于检测人体股腘动脉 CTO 中的微通道。这种成像技术安全且微创，可能是选择闭塞交叉方法的实用方法。需要进一步的工作来确定识别微通道是否可以用于改善治疗决策，并提供对股腘 CTO 自然史的更好理解。
