Yasuda G, Takizawa T, Takasaki I, Shionoiri H, Umemura S, Shimoyama K
Second Department of Internal Medicine, Yokohama City University School of Medicine, Yokohama, Japan.
Nephrol Dial Transplant. 1998 Jul;13(7):1690-5. doi: 10.1093/ndt/13.7.1690.
Intravascular ultrasound (IVUS) imaging, a new modality, may be feasible and useful for the assessment of atherosclerotic renal arteries. However, comparison between in vivo and in vitro studies to confirm pathological changes corresponding with IVUS findings obtained from renal arteries was not fully evaluated.
We evaluated ultrasound images of 18 post-mortem human renal arteries and cross-sectional IVUS images of main renal arteries in five patients with renal artery stenosis (RAS) or essential hypertension.
In vitro studies have shown that renal-artery images had three layers when the arteries had fibrous intimal thickening and medial hypertrophy. Renal arteries, in which the fibrous intima was not well developed, showed circumferentially homogeneous bright echoes. In patients with atherosclerotic RAS and essential hypertension, IVUS images showed hyperechoic areas in the renal arterial walls, probably due to atherosclerosis. Typical three-layered ultrasound appearance was not easily seen during in vivo studies.
Our findings suggest that hyperechoic images can be a diagnostic clue of atherosclerosis However, in vitro results do not always correspond exactly to in vivo findings, and caution is needed when findings from in vitro IVUS imaging studies are applied to in vivo studies.
血管内超声（IVUS）成像作为一种新的检查方式，可能对评估动脉粥样硬化性肾动脉是可行且有用的。然而，体内和体外研究之间的比较，以确认与从肾动脉获得的IVUS结果相对应的病理变化，尚未得到充分评估。
我们评估了18条尸检人类肾动脉的超声图像以及5例肾动脉狭窄（RAS）或原发性高血压患者主肾动脉的横断面IVUS图像。
体外研究表明，当肾动脉出现纤维内膜增厚和中层肥厚时，肾动脉图像有三层结构。纤维内膜发育不良的肾动脉显示出周向均匀的明亮回声。在动脉粥样硬化性RAS和原发性高血压患者中，IVUS图像显示肾动脉壁上有高回声区，可能是由于动脉粥样硬化所致。在体内研究中不容易看到典型的三层超声表现。
我们的研究结果表明，高回声图像可能是动脉粥样硬化的诊断线索。然而，体外结果并不总是与体内发现完全相符，当将体外IVUS成像研究的结果应用于体内研究时需要谨慎。
