Liver Track Embolization After Islet Cell Transplant: Comparison of Two Techniques

The purpose of this study was to compare the efficacy and safety of microfibrillar collagen paste with those of gelatin sponge for liver track embolization after islet cell transplants.

In a single-institution, retrospective study, 37 patients underwent 66 islet cell transplants from January 2005 through October 2015. Transplants were performed with 6-French transhepatic access, systemic anticoagulation, pretransplant and posttransplant portal venous pressure measurement, and image-guided liver track embolization with gelatin sponge (2005-2011) or microfibrillar collagen paste (2012-2015). The findings on 20 patients (two men, 18 women; mean age, 48 years) who underwent 35 gelatin sponge embolizations were compared with the findings on 13 patients (six men, seven women; mean age, 48 years) who underwent 22 microfibrillar collagen paste embolizations (four patients, nine procedures without embolization excluded). Medical record review was used to compare laboratory test results, portal venous pressures, and 30-day adverse bleeding events (classified according to Society of Interventional Radiology and Bleeding Academic Research Consortium criteria) between groups.

The technical success rates were 100% in the microfibrillar collagen paste group and 91% in the gelatin sponge group. Group characteristics were similar, there being no differences in platelet count, partial thromboplastin time, or number of islet cell transplants per patient (p > 0.05). A statistical difference in international normalized ratio (1.0 versus 1.1) was not clinically significant (p = 0.012). Posttransplant portal venous pressure was slightly higher among patients treated with gelatin sponge (13 versus 9 mm Hg, p = 0.002). No bleeding occurred after microfibrillar collagen paste embolization, whereas nine bleeding events followed gelatin sponge embolization (0% versus 26%, p = 0.020). In univariate comparison of bleeding and nonbleeding groups, the use of gelatin sponge was statistically associated with postprocedure hemorrhage.

Microfibrillar collagen paste is effective and safe for liver track embolization to prevent bleeding after islet cell transplants. It appears to be more efficacious than gelatin sponge.