CVPath Institute, Gaithersburg, MD, USA.
EuroIntervention. 2021 Oct 1;17(8):e688-e698. doi: 10.4244/EIJ-D-20-01336.
In peripheral artery disease, two different types of calcification are frequently observed, i.e., medial and intimal calcification.
The aim of this study was to determine the ability of intravascular ultrasound (IVUS) imaging and optical frequency domain imaging (OFDI) to detect medial and intimal calcification in human peripheral arteries.
We performed ex vivo intravascular imaging of cadaveric human peripheral arteries with calcifications. IVUS and OFDI images were co-registered with histology. A total of 12 legs from nine patients were examined, and 438 cross-sectional images were co-registered with histology.
OFDI could detect 183 of 231 intimal calcifications by histology, whereas IVUS could detect 194 (OFDI: sensitivity 79%, specificity 86%, area under the curve [AUC] 0.83; IVUS: sensitivity 84%, specificity 85%, AUC 0.85). Of 245 medial calcifications by histology, 160 and 164 were detected by OFDI and IVUS, respectively (OFDI: sensitivity 65%, specificity 85%, AUC 0.75; IVUS: sensitivity 67%, specificity 80%, AUC 0.74). Medial calcification with overlying intimal calcification (overlapped calcification) and an unclear border between intima and media were the main reasons for misdiagnosis. Without those 89 overlapped calcifications, sensitivity in both OFDI and IVUS was improved (OFDI: sensitivity 81%, specificity 85%, AUC 0.83; IVUS: sensitivity 88%, specificity 80%, AUC 0.84).
There are limitations in detecting medial calcification in overlapped intimal calcification and with an unclear border between intima and media by both IVUS and OFDI. It is important to distinguish medial calcification from intimal calcification before proceeding with endovascular therapy since different approaches will be required.
在外周动脉疾病中，常观察到两种不同类型的钙化，即中膜钙化和内膜钙化。
本研究旨在确定血管内超声（IVUS）成像和光频域成像（OFDI）检测人外周动脉中膜和内膜钙化的能力。
我们对有钙化的人体外周动脉进行了尸体离体血管内成像。将 IVUS 和 OFDI 图像与组织学进行了配准。共检查了 9 例患者的 12 条腿，共对 438 个横截面图像进行了组织学配准。
OFDI 通过组织学检测到 231 个内膜钙化中的 183 个，而 IVUS 则检测到 194 个（OFDI：敏感性 79%，特异性 86%，曲线下面积 [AUC] 0.83；IVUS：敏感性 84%，特异性 85%，AUC 0.85）。245 个中膜钙化中，OFDI 和 IVUS 分别检测到 160 和 164 个（OFDI：敏感性 65%，特异性 85%，AUC 0.75；IVUS：敏感性 67%，特异性 80%，AUC 0.74）。中膜钙化伴有内膜钙化（重叠钙化）和内膜与中膜之间边界不清是误诊的主要原因。没有这 89 个重叠钙化，OFDI 和 IVUS 的敏感性均得到提高（OFDI：敏感性 81%，特异性 85%，AUC 0.83；IVUS：敏感性 88%，特异性 80%，AUC 0.84）。
IVUS 和 OFDI 在检测重叠的内膜钙化和内膜与中膜之间边界不清的中膜钙化方面存在局限性。在进行血管内治疗之前，区分中膜钙化和内膜钙化很重要，因为需要采用不同的方法。
