BioGlue Iceball Stabilization to Minimize the Risk of Hemorrhage During Laparoscopic Renal Cryoablation

The recent progress of tissue adhesives in design strategies, adhesive mechanism and applications

Tissue adhesives have emerged as an effective method for wound closure and hemostasis in recent decades, due to their ability to bond tissues together, preventing separation from one tissue to another. However, existing tissue adhesives still have several limitations. Tremendous efforts have been invested into developing new tissue adhesives by improving upon existing adhesives through different strategies. Therefore, highlighting and analyzing these design strategies are essential for developing the next generation of advanced adhesives. To this end, we reviewed the available strategies for modifying traditional adhesives (including cyanoacrylate glues, fibrin sealants and BioGlue), as well as design of emerging adhesives (including gelatin sealants, methacrylated sealants and bioinspired adhesives), focusing on their structures, adhesive mechanisms, advantages, limitations, and current applications. The bioinspired adhesives have numerous advantages over traditional adhesives, which will be a wise direction for achieving tissue adhesives with superior properties.

Irreversible electroporation: evaluation of nonthermal and thermal ablative capabilities in the porcine kidney

OBJECTIVE

To compare the renal ablative capabilities of nonthermal irreversible electroporation (NT-IRE) with those of thermal irreversible electroporation (T-IRE) in a porcine model.

MATERIALS AND METHODS

A total of 24 laparoscopic renal ablations were performed in 12 pigs using a novel generator capable of alternately delivering NT-IRE and T-IRE. Each pig underwent unilateral interpolar ablation straddling the renal pelvis and lower pole ablation, using a single modality. The pigs were killed at 24 hours and 7 and 21 days. Basic serum laboratory tests, cardiac enzyme levels, and retrograde pyelograms were obtained before and immediately after ablation and at death. Ablation adequacy and lesion size were assessed by histologic examination.

RESULTS

All procedures were successfully completed without complications. For NT-IRE vs T-IRE, the median lesion size (long axis) at 24 hours, 7 days and 21 days was 3.0 vs 3.3 cm (P = 1.0), 2.5 vs 3.9 cm (P = .04), and 1.2 vs 2.8 cm (P = .03), respectively. Prolonged urinary extravasation and collecting system scarring were observed only for T-IRE. Both NT-IRE and T-IRE ablated the renal tissue adequately. NT-IRE was characterized by acute hemorrhagic necrosis, sparing the large blood vessels and extracellular matrix, and T-IRE by coagulation necrosis with associated moderate inflammation.

CONCLUSION

NT-IRE and T-IRE both safe and effectively ablate normal porcine kidneys. NT-IRE created smaller lesions with unique histologic characteristics. Significant collecting system injury occurred with T-IRE. Additional preclinical evaluation aimed at optimizing the ablation protocols is needed.

BioGlue surgical adhesive as a thermal reflector during laparoscopic cryoablation: effect on iceball size and ablation zone diameter

In a porcine model, the application of BioGlue did not appear to increase the size of the iceball generated, nor did it change the amount of subjective bleeding noted.

Background and Objectives:

Cryoablation represents an alternative for treating small renal cortical neoplasms (RCN). Previously, we demonstrated that applying BioGlue during cryoablation diminished bleeding and incidentally noted that the iceballs seemed larger than those in controls. We examined the effects of BioGlue as a thermal insulator of cryoablated tissue to determine its effect on iceball size.

Methods:

Laparoscopic cryoablation (LCA) was performed in 6 female pigs (24 ablations) by using a single 1.47-mm cryoablation probe. One pole of each kidney was randomly treated with BioGlue prior to ablation, while the contralateral pole was the untreated control. The size of the iceball was measured using laparoscopic ultrasound. The tissue ablation zone was measured grossly after the specimens were harvested. We also documented the amount of bleeding on a subjective scale.

Results:

There were no differences in the diameters of the iceballs between the BioGlue and control groups when measured with laparoscopic ultrasound (P=.85). Similarly, the ablation zones on gross measurement were not significantly different (P=.47). No difference occurred in the amount of subjective bleeding.

Conclusions:

In a porcine model, the application of BioGlue prior to LCA does not appear to increase the size of the iceball generated. No change was observed in the amount of subjective bleeding as a result of using BioGlue.