Lettau Michael, Kotter Elmar, Bendszus Martin, Hähnel Stefan
Division of Neuroradiology, Department of Neurosurgery, University of Freiburg, Medical Center, Breisacher Street 64, 79106 Freiburg, Germany; Division of Neuroradiology, Department of Neurology, University of Heidelberg, Medical Center, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany.
Department of Radiology, University of Freiburg Medical Center, Breisacher Street 64, 79106 Freiburg, Germany.
J Neuroradiol. 2014 Oct;41(4):259-68. doi: 10.1016/j.neurad.2013.10.003. Epub 2014 Jan 9.
CT angiography (CTA) is an increasingly used method for evaluation of stented vessel segments. Our aim was to compare the appearance of different carotid artery stents in vitro on CTA using different CT scanners. Of particular interest was the measurement of artificial lumen narrowing (ALN) caused by the stent material within the stented vessel segment to determine whether CTA can be used to detect in-stent restenosis.
CTA appearances of 16 carotid artery stents of different designs and sizes (4.0 to 11.0 mm) were investigated in vitro. CTA was performed using 16-, 64- and 320-row CT scanners. For each stent, artificial lumen narrowing (ALN) was calculated.
ALN ranged from 18.77% to 59.86%. ALN in different stents differed significantly. In most stents, ALN decreased with increasing stent diameter. In all but one stents, ALN using sharp image kernels was significantly lower than ALN using medium image kernels. Considering all stents, ALN did not significantly differ using different CT scanners or imaging protocols.
CTA evaluation of vessel patency after stent placement is possible, but is considerably impaired by ALN. Investigators should be informed about the method of choice for every stent and stent manufacturers should be aware of potential artifacts caused by their stents during noninvasive diagnostic methods such as CTA.
CT血管造影（CTA）是一种越来越常用于评估支架置入血管节段的方法。我们的目的是在体外使用不同的CT扫描仪比较不同颈动脉支架在CTA上的表现。特别感兴趣的是测量支架置入血管节段内支架材料引起的人工管腔狭窄（ALN），以确定CTA是否可用于检测支架内再狭窄。
对16个不同设计和尺寸（4.0至11.0mm）的颈动脉支架进行体外CTA表现研究。使用16排、64排和320排CT扫描仪进行CTA检查。计算每个支架的人工管腔狭窄（ALN）。
ALN范围为18.77%至59.86%。不同支架的ALN差异显著。在大多数支架中，ALN随支架直径增加而降低。除一个支架外，使用锐利图像内核时的ALN显著低于使用中等图像内核时的ALN。考虑所有支架，使用不同的CT扫描仪或成像方案时，ALN无显著差异。
支架置入后血管通畅性的CTA评估是可行的，但会受到ALN的显著影响。研究人员应了解每种支架的选择方法，支架制造商应意识到其支架在CTA等无创诊断方法中可能引起的伪影。
