Percutaneous Thrombin Injection Based on Computational Fluid Dynamics of Femoral Artery Pseudoaneurysms

Objective@#To analyze the computational fluid dynamics (CFD) of femoral artery pseudoaneurysm (FAP), identify a suitable location and timing for percutaneous thrombin injection (PTI) based on this analysis, and report our clinical experience with the procedure. @*Materials and Methods@#CFD can be used to analyze the hemodynamics of the human body. An analysis using CFD recommended that the suitable location of the needle tip for PTI is at the center of the aneurysm sac and the optimal timing for starting PTI is during the early inflow phase of blood into the sac. Since 2011, seven patients (three male and four female; median age, 60 years [range, 43–75 years]) with FAP were treated with PTI based on the devised suitable location and time. Prior to the procedure, color Doppler ultrasonography was performed to determine the location and timing of the thrombin injection. @*Results@#The technical success rate of the PTI was 100%. The amount of thrombin used for the procedure ranged from 200 IU to 1000 IU (median, 500 IU). None of the patients experienced any symptoms or signs of embolic complications during the procedure. Follow-up CT images did not reveal any embolism in the lower extremities and showed complete thrombosis of the pseudoaneurysm. @*Conclusion@#Based on our study of CFD, PTI administered centrally in the FAP during early inflow, as seen on color Doppler, can be an effective technique.

Experimental renal and hepatic artery embolization with a new embolic agent, atelocollagen, in a porcine model.

PURPOSE: We aimed to investigate the potentiality of atelocollagen, a new embolic agent which is collagen type I in a porcine experimental model. MATERIALS AND METHODS: Three pigs underwent transcatheter embolization of lower interlobular arteries of the renal artery (n=6) and one branch of the hepatic artery (n=3) with collagen type I. Angiography was performed prearterial, during, and postarterial embolization. After the procedure, samples from the embolized organs were evaluated by histological analysis. RESULTS: Six lower interlobular renal arteries and three hepatic arteries were successfully embolized by administration of 0.8±0.3 mL and 2.9±1.2 mL, respectively, of the collagen type I. Histological findings of the embolized kidney specimens showed that the collagenous materials filled the arterial lumen, whose size ranged from 2.02 to 839.82 µm and reached the level of afferent arteries of glomerular tufts. Although the area of occluded arteries of the liver was smaller than the kidney, histological findings of the liver specimens showed that the collagenous materials filled small arterial lumens from 2.81 to 187.86 µm in diameter. CONCLUSION: Atelocollagen, a collagen type I, has the potential to be used to embolize the distal vessels of both renal and hepatic arteries.