Department of Physiology and Biomedical Engineering, Rochester, MN 55905, USA.
Int J Cardiovasc Imaging. 2013 Aug;29(6):1325-33. doi: 10.1007/s10554-013-0198-6. Epub 2013 Feb 27.
To evaluate the potential of whole-body CT to detect localized areas of decreased or increased vascularity in coronary arterial walls. We used both microsphere embolization of coronary artery vasa vasorum to generate small areas of hypoperfusion and surrounding hyperperfusion of the arterial wall and diet-induced hypercholesterolemia. As a stimulus for localized angiogenesis, such as occurs in early plaque formation in the coronary arterial wall, microspheres were injected selectively into the LAD coronary artery lumens of anesthetized pigs. Fourteen pigs (acute) then had a segment of their LAD harvested during injection of contrast medium and snap-frozen for subsequent cryo-static micro-CT. An additional thirteen pigs (chronic) were allowed to recover, fed a high cholesterol diet and 3 months later were again anesthetized and a segment of the LAD artery harvested and scanned. The spatial distribution of the contrast agent within the arterial wall was measured in contiguous micro-CT images at right angles to the lumen axis with the area of wall in each cross-sectional image being approximately (0.1 mm)(3) in size. In the acute animals there were no localized areas of increased contrast around the hypoperfused embolized perfusion territories in the arterial wall, but in the chronic animals the hypoperfused areas were surrounded by increased contrast. These results suggest that CT might be able to detect localized regions of increased vascularity in the arterial wall as an indicator of early atherosclerotic stimulation of vasa vasorum proliferation.
为了评估全身 CT 检测冠状动脉壁局部区域血管减少或增加的潜力。我们使用冠状动脉血管丛微球栓塞来产生小面积的灌注不足和动脉壁周围的高灌注，以及饮食诱导的高胆固醇血症。作为局部血管生成的刺激物，如在冠状动脉壁早期斑块形成中发生的那样，微球被选择性地注入麻醉猪的 LAD 冠状动脉管腔中。然后，14 只猪（急性）在注射对比剂时采集其 LAD 的一段，并立即冷冻用于随后的冷冻静态 micro-CT。另外 13 只猪（慢性）被允许恢复，给予高胆固醇饮食，3 个月后再次麻醉并采集一段 LAD 动脉进行扫描。在与管腔轴成直角的连续 micro-CT 图像中测量动脉壁内造影剂的空间分布，每个横截面图像中的壁面积约为 (0.1 mm)(3)。在急性动物中，在灌注不足的栓塞灌注区域周围没有局部区域的对比度增加，但在慢性动物中，灌注不足区域被对比度增加所包围。这些结果表明，CT 可能能够检测到动脉壁中局部区域的血管增多，作为血管丛增殖的早期动脉粥样硬化刺激的指标。
