Radiofrequency-assisted partial splenectomy: Histopathological and immunological assessment of the splenic remnant in a porcine model

Abstract

Radiofrequency (RF) ablation has recently been expanded from palliative treatment into tissue-preserving surgery with controversial results. RF has been accused of septic complications and dysfunction of the target organ due to uncontrolled energy distribution. The aim of this study was to evaluate the short- and long-term implications of RF energy to the remaining splenic tissue after laparoscopic and open RF-assisted partial splenectomy. Thirty pigs randomly underwent laparoscopic RF partial splenectomy (n = 10), open RF partial splenectomy (n = 10) using the Radionics Cooltip radiofrequency system (Tyco Hellas), while a third group (n = 10) underwent the conventional procedure. Intraoperative parameters were recorded. Complete blood counts, along with splenic function tests, were estimated preoperatively, immediately postoperatively, and at 1 and 6 months after the procedure. Histology was also evaluated. A separate group of five animals randomly undergo conventional resection (n = 2) and open RF resection (n = 3). These animals were sacrificed 1 month postoperatively and were used for histology only. The blood loss was minimal in both RF groups. No septic complications were observed throughout the follow-up period. Laboratory values at 1 month postoperatively showed decreased splenic function in both RF groups. Histology at 1 month was indicative of a chronic inflammatory reaction to the RF groups whereas, in the control group, prominent hypervascular granulated tissue was observed. Six months postoperatively, the platelet count remained elevated in the RF groups. Histology revealed intense fibrosis at the ablation site, as opposed to friable granulated tissue in the conventional group. Radiofrequency energy acts as an excellent haemostatic tool. The healing process shifts from the thermal injury to chronic inflammatory reaction and, 6 months later, to intense fibrosis as opposed to the hypervascular granulated tissue presented in the nonablated spleen. However, the longer the RF energy is applied, the more the splenic function is transiently affected.