An animal experimental study using high-resolution C-arm CT to evaluate the expansion degree and wall apposition of the intracranial blood flow diverter
Objective To explore the application value of high-resolution C-arm CT technology in the evaluation of stent opening and wall apposition during the placement of blood flow diverters(FD)in the carotid arteries of Bama miniature pigs.Methods Tubridge FD was inserted into the carotid artery of Bama miniature pigs using endovascular treatment.A high-resolution C-arm CT scan was performed immediately after the operation to evaluate the expansion degree of the FD and the quality of the post-processed images.Then a three-dimensional digital subtraction angiography(3D-DSA)scan of the FD-inserted blood vessel was performed.The post-processing workstation was used to have high-resolution C-arm CT and 3D-DSA image reconstructed using dual-volume fusion technology to obtain the fused image(referred to as the dual-volume reconstruction method),and diluted contrast agent was continuously injected while performing the high-resolution C-arm CT scan.The stent vascular reconstruction images obtained later(referred to as the diluted contrast medium method)were compared,and the radiation exposure doses of the two operating methods were documented to evaluate their accuracy and safety in FD apposition assessment.The occurrence of adverse events during surgery and within 24 hours after FD implantation was observed.Results A total of 9 Tubridge FDs were placed in the left carotid arteries of 9 Bama miniature pigs.High-resolution C-arm CT plain scan reconstructed images showed that 8 FDs had full expansion and 1 case of underexpansion of the distal end of the FD.The image quality was grade Ⅰ in 8 cases and grade Ⅱ in 1 case.In terms of stent apposition,both the double-volume reconstruction method and the diluted contrast agent method could clearly demonstrate the apposition of FDs.Among them,8 FDs showed good apposition(apposition score:0 points),and 1 FD showed poor apposition at the distal end(apposition score:1 point,classified as type Ⅰa).The consistency rate of the two assessment results was 100％.In terms of radiation exposure dose,the dual-volume reconstruction method was significantly higher than the diluted contrast agent method(906.89±44.49 μGym2 vs.725.44±42.17 μGym2,t=24.36,P＜0.001).Two experimental pigs suffered from moderate vasospasm during the application of diluted contrast media.No complications such as vascular dissection or thrombus detachment were observed in all animals during the operation and within 24 hours after operation.Conclusion High-resolution C-arm CT can clearly display the fine structure and full expansion of the domestic intracranial blood flow diverters,and combined with a variety of post-processing techniques,its wall apposition can be effectively observed.
万方数据
维普
