Chiaki Takasawa, Presenter: Nothing to Disclose

Kazumasa Seiji MD, PhD, Abstract Co-Author: Nothing to Disclose

Kenichi Matsunaga, Abstract Co-Author: Nothing to Disclose

Toshio Matsuhashi, Abstract Co-Author: Nothing to Disclose

Kei Takase, Abstract Co-Author: Nothing to Disclose

Shoki Takahashi MD, Abstract Co-Author: Nothing to Disclose

The purpose is to reveal the property of NBCA-LIP mixture and to obtain fundamental evidence of the optimal NBCA-Lip ratio for clinical use.

We measured the viscosity of samples at eight different NBCA-Lip ratios 〔NBCA: Lipiodol =1:1 (NBCA density 50%), 1:2(33%), 1:3(25%), 1:4(20%), 1:5(16.7%), 1:6(14.3%) , 1:7(12.5%), 1:8(11.1%), 1:9(10%)〕. As an index of the diffusing capacity of the NBCA-Lip polymer in blood, we measured the area of the polymer. To determine the polymerization time, NBCA-Lip was dropped on blood, and we recorded the state of polymerization by video. Selective embolization of the branch of renal artery with NBCA-Lip (mixture ratio of 1:1, 1:3, or 1:9) was performed. Eight kidneys were embolized using each NBCA-Lip ratio. Immediately after embolization, CT volumetry of the specimen was performed and the vascular bed in which the embolic material was distributed was evaluated. We evaluated the cortex/total kidney ratio of the vascular bed and considered this to be the index of the distal embolization effect. A histopathological evaluation determined the following two points to evaluate how distal the NBCA-Lip travelled in the artery: Point 1: The smallest minor axis of the arteriole containing embolic material in the lumen was measured in each kidney. Point 2: The number of arterioles with a minor axis ≤40 μm containing embolic material in the lumen was counted.  

The viscosity, the area of the polymer and the polymerization time increased with the Lipiodol volume. The vascular bed of the embolized blood vessel tended to increase as the Lipiodol volume decreased. In addition, the embolized vascular bed was significantly bigger with NBCA-Lip ratios of 1:3 and 1:9 than with 1:1, no significant difference between 1:3 and 1:9 was observed. At a low NBCA density, narrow arterioles were embolized, and the peripheral distribution of the embolic material tended to be broad. More arterioles were embolized at 1:3 and 1:9 ratios than at 1:1, whereas no significant difference was found between 1:3 and 1:9.  

For NBCA-Lip ratios of 1:1–1:9, embolization occurred more distally and involved a wider vascular bed with decreasing NBCA densities. We postulated that polymerization time had a greater influence on this tendency than did the viscosity of the NBCA-Lip.

We suggested the evidence of the optimal NBCA-Lip ratio for successful TAE.  

Takasawa, C, Seiji, K, Matsunaga, K, Matsuhashi, T, Takase, K, Takahashi, S, A Fundamental Examination of the Effect of N-butyl-2-cyanoacrylate (NBCA)-iodized Oil Mixtures on Arterial Embolization.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11020170.html