Saita Ten, Fujii Kenichi, Hao Hiroyuki, Imanaka Takahiro, Shibuya Masahiko, Fukunaga Masashi, Miki Kojiro, Tamaru Hiroto, Horimatsu Tetsuo, Nishimura Machiko, Sumiyoshi Akinori, Kawakami Rika, Naito Yoshiro, Kajimoto Noriko, Hirota Seiichi, Masuyama Tohru
Cardiovascular Division, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 6638501, Japan.
Department of Surgical Pathology, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan.
Eur Heart J Cardiovasc Imaging. 2017 Mar 1;18(3):342-349. doi: 10.1093/ehjci/jew054.
This study evaluated whether optical frequency domain imaging (OFDI) could identify various coronary calcifications and accurately measure calcification thickness in comparison with histopathology.
A total of 902 pathological cross-sections from 44 coronary artery specimens of human cadavers were examined to compare OFDI and histological images. Histological coronary calcification was classified into four different types: (i) superficial dense calcified plates, (ii) deep intimal calcification, (iii) scattered microcalcification, and (iv) calcified nodule. The thickness of calcification was measured when both the leading and trailing edges of calcification were visible on OFDI. Of the 902 histological cross-sections, 158 (18%) had calcification: 105 (66%) were classified as superficial dense calcified plates, 20 (13%) as deep intimal calcifications, 30 (19%) as scattered microcalcifications, and 3 (2%) as calcified nodules. Superficial dense calcified plates appeared as well-delineated heterogeneous signal-poor regions with sharp borders on OFDI. Deep intimal calcifications could not be identified on OFDI. Scattered microcalcification appeared as homogeneous low intensity areas with indiscriminant borders. Calcified nodule, a high-backscattering protruding mass with an irregular surface, also appeared as a low intensity area with a diffuse border. The ROC analysis identified calcium thicknesses <893 µm as cut points for the prediction of measurable calcification (72% sensitivity and 91% specificity, area under the curve = 0.893, P < 0.001).
Our study demonstrated the potential capability of OFDI to characterize various types of coronary calcifications, which may contribute to the understanding of the pathogenesis of coronary atherosclerosis.
本研究评估光学频域成像（OFDI）与组织病理学相比，能否识别各种冠状动脉钙化并准确测量钙化厚度。
共检查了44例人体尸体冠状动脉标本的902个病理切片，以比较OFDI和组织学图像。组织学上冠状动脉钙化分为四种不同类型：（i）浅表致密钙化板，（ii）内膜深层钙化，（iii）散在微钙化，（iv）钙化结节。当钙化的前缘和后缘在OFDI上均可见时，测量钙化厚度。在902个组织学切片中，158个（18%）有钙化：105个（66%）被分类为浅表致密钙化板，20个（13%）为内膜深层钙化，30个（19%）为散在微钙化，3个（2%）为钙化结节。浅表致密钙化板在OFDI上表现为边界清晰的异质性信号缺失区域，边界锐利。内膜深层钙化在OFDI上无法识别。散在微钙化表现为边界不清的均匀低强度区域。钙化结节是一个表面不规则的高后向散射突出肿块，也表现为边界模糊的低强度区域。ROC分析确定钙化厚度<893 µm为可测量钙化预测的切点（敏感性72%，特异性91%，曲线下面积=0.893，P<0.001）。
我们的研究证明了OFDI表征各种类型冠状动脉钙化的潜在能力，这可能有助于理解冠状动脉粥样硬化的发病机制。
