Shinichi Ohta, Presenter: Nothing to Disclose

Norihisa Nitta MD, Abstract Co-Author: Nothing to Disclose

Hideji Otani MD, Abstract Co-Author: Nothing to Disclose

Shobu Watanabe MD, Abstract Co-Author: Nothing to Disclose

Yuki Tomozawa MD, Abstract Co-Author: Nothing to Disclose

Kiyoshi Murata MD, Abstract Co-Author: Nothing to Disclose

Akinaga Sonoda MD, Abstract Co-Author: Nothing to Disclose

Ayumi Seko MD, Abstract Co-Author: Nothing to Disclose

Keiko Tsuchiya, Abstract Co-Author: Nothing to Disclose

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

To evaluate embolic effect and degradability of degradable gelatin microspheres (GMSs) which have a variety of particle sizes in canine hepatic embolization.

4 different-sized (100, 200, 500, and 1000 μm) GMSs and Gelpart (1mm) which is a porous gelatin embolic material available in Japan were used. 50 beagles (N=10 in each group) were used for the hepatic embolization. Celiac angiography was performed before and after embolization of left hepatic artery. Follow-up celiac angiography was performed 2 days (N=4), 14 days (N=2), or 28 days (N=4) after the embolization in each group, and then liver were removed for histopathological evaluation. Reperfusion of left hepatic artery was evaluated in terms of demonstration of arterial brunches. In hepatic specimens residual GMSs were checked and then the surrounding tissue injury, the inflammatory change, and embolic formation of the artery were evaluated. Blood and serum chemistry were also evaluated.

Mean amount used of GMSs (100, 200, 500, and 1000μm) and Gelpart was 55, 35, 31, 15.5, and 14.5mg, respectively. Hepatic arterial reperfusion was not observed 2days after the embolization in each group; however, it was completely observed 28 days after the embolization. In histopathological specimens the number of smaller GMSs was remarkably decreased 28days after the embolization, while that of larger GMSs was slightly decreased. The surrounding tissue injury and the inflammatory change of the artery were observed in each group; however, no difference was confirmed between each group. The embolic formation of the artery was observed more in the smaller GMSs than in the larger GMSs. Elevation of AST, ALT and CRP was seen in each group 2 days after the embolization; however, it was transient elevation.

Particle size of GMSs didn’t affect the reperfusion in the canine hepatic angiography. On the contrary, particle size of GMSs affected the degradability since the smaller GMS was degraded faster than larger GMSs. Smaller GMSs had strong embolic formation, although hepatic damage using smaller GMSs was same as larger GMSs.

Degradable GMSs of various sizes have enough embolic effect and are recommended for a customized TAE procedure by changing the level of occlusion.

Ohta, S, Nitta, N, Otani, H, Watanabe, S, Tomozawa, Y, Murata, K, Sonoda, A, Seko, A, Tsuchiya, K, Takahashi, M, Degradable Gelatin Microspheres: Evaluation of Embolic Effect and Degradability Due to the Difference in Particle Size.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11007420.html