CO 2 Digital SubtractionSplenoportography with the “Skinny” Needle: Experimental Study in aSwine Model

Abstract

Purpose: To evaluate the safety and theeffectiveness of CO 2 splenoportography with the“skinny” needle. Methods: A flexible, 22 gaugeneedle (“skinny” needle) was introduced into the exteriorizedspleens of five pigs. After checking the intrasplenic positioning withCO 2 injection, increasing doses of CO 2 (10–60cm 3 ) were injected using a dedicated CO 2 injector with digital imaging. The puncture sites were observed duringand after CO 2 injections, and after removal of the needle.The spleens were then removed for gross and microscopicexamination. Results: In all animals digital subtractionCO 2 splenoportograms showed the splenic, extra- andintrahepatic portal veins, and the most distal portion of the superiormesenteric vein. No CO 2 extravasation occurred in thespleen. There was no significant bleeding from the puncture site afterremoval of the needle. Gross and microscopic examination revealed noevidence of splenic rupture or intrasplenic hematoma. Conclusion: CO 2 splenoportography with the“skinny” needle is a safe and simple method of visualizing theportal vein and its branches. Careful appraisals of the clinicalusefulness of the method will be needed in various clinical settings.