Limits...
Radiofrequency ablation of rabbit liver in vivo: effect of the pringle maneuver on pathologic changes in liver surrounding the ablation zone.

Kim SK, Lim HK, Ryu JA, Choi D, Lee WJ, Lee JY, Lee JH, Sung YM, Cho EY, Hong SM, Kim JS - Korean J Radiol (2004 Oct-Dec)

Bottom Line: Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver.None of the above changes was found in the livers ablated without the Pringle maneuver.On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (p < 0.05) Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma surrounding the ablation zone compared with RF ablation without the Pringle maneuver.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Kangnam-gu, Seoul, Korea.

ABSTRACT

Objective: We wished to evaluate the effect of the Pringle maneuver (occlusion of both the hepatic artery and portal vein) on the pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone in rabbit livers.

Materials and methods: Radiofrequency (RF) ablation zones were created in the livers of 24 rabbits in vivo by using a 50-W, 480-kHz monopolar RF generator and a 15-gauge expandable electrode with four sharp prongs for 7 mins. The tips of the electrodes were placed in the liver parenchyma near the porta hepatis with the distal 1 cm of their prongs deployed. Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver. Three animals of each group were sacrificed immediately, three days (the acute phase), seven days (the early subacute phase) and two weeks (the late subacute phase) after RF ablation. The ablation zones were excised and serial pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone were evaluated.

Results: With the Pringle maneuver, portal vein thrombosis was found in three cases (in the immediate [n=2] and acute phase [n=1]), bile duct dilatation adjacent to the ablation zone was found in one case (in the late subacute phase [n=1]), infarction adjacent to the ablation zone was found in three cases (in the early subacute [n=2] and late subacute [n=1] phases). None of the above changes was found in the livers ablated without the Pringle maneuver. On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (p < 0.05)

Conclusion: Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma surrounding the ablation zone compared with RF ablation without the Pringle maneuver. Therefore, we suggest that RF ablation with the Pringle maneuver should be performed with great caution in order to avoid unwanted thermal injury.

Show MeSH

Related in: MedlinePlus

Microphotographs (H & E, ×100) of resected specimens obtained after radiofrequency ablation with the Pringle maneuver. The microphotograph of the resected specimen obtained immediately after ablation (A) shows the distended portal vein (arrows), suggesting congestion, while the portal vein (arrows) is normal in the specimen obtained two weeks after ablation (B).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2698168&req=5

Figure 7: Microphotographs (H & E, ×100) of resected specimens obtained after radiofrequency ablation with the Pringle maneuver. The microphotograph of the resected specimen obtained immediately after ablation (A) shows the distended portal vein (arrows), suggesting congestion, while the portal vein (arrows) is normal in the specimen obtained two weeks after ablation (B).

Mentions: The mean grades of the microscopic variables surrounding the ablation zones created in the rabbit livers with the Pringle maneuver in each phase are summarized in Table 3. Portal congestion in livers ablated with the Pringle maneuver at the immediate and acute phases showed more significant changes than that in those livers at the early and late subacute phases (Fig. 7). Centrilobular necrosis in livers ablated with the Pringle maneuver at the early and late subacute phases showed more significant changes than the changes in those livers at the immediate and acute phase.


Radiofrequency ablation of rabbit liver in vivo: effect of the pringle maneuver on pathologic changes in liver surrounding the ablation zone.

Kim SK, Lim HK, Ryu JA, Choi D, Lee WJ, Lee JY, Lee JH, Sung YM, Cho EY, Hong SM, Kim JS - Korean J Radiol (2004 Oct-Dec)

Microphotographs (H & E, ×100) of resected specimens obtained after radiofrequency ablation with the Pringle maneuver. The microphotograph of the resected specimen obtained immediately after ablation (A) shows the distended portal vein (arrows), suggesting congestion, while the portal vein (arrows) is normal in the specimen obtained two weeks after ablation (B).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2698168&req=5

Figure 7: Microphotographs (H & E, ×100) of resected specimens obtained after radiofrequency ablation with the Pringle maneuver. The microphotograph of the resected specimen obtained immediately after ablation (A) shows the distended portal vein (arrows), suggesting congestion, while the portal vein (arrows) is normal in the specimen obtained two weeks after ablation (B).
Mentions: The mean grades of the microscopic variables surrounding the ablation zones created in the rabbit livers with the Pringle maneuver in each phase are summarized in Table 3. Portal congestion in livers ablated with the Pringle maneuver at the immediate and acute phases showed more significant changes than that in those livers at the early and late subacute phases (Fig. 7). Centrilobular necrosis in livers ablated with the Pringle maneuver at the early and late subacute phases showed more significant changes than the changes in those livers at the immediate and acute phase.

Bottom Line: Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver.None of the above changes was found in the livers ablated without the Pringle maneuver.On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (p < 0.05) Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma surrounding the ablation zone compared with RF ablation without the Pringle maneuver.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Kangnam-gu, Seoul, Korea.

ABSTRACT

Objective: We wished to evaluate the effect of the Pringle maneuver (occlusion of both the hepatic artery and portal vein) on the pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone in rabbit livers.

Materials and methods: Radiofrequency (RF) ablation zones were created in the livers of 24 rabbits in vivo by using a 50-W, 480-kHz monopolar RF generator and a 15-gauge expandable electrode with four sharp prongs for 7 mins. The tips of the electrodes were placed in the liver parenchyma near the porta hepatis with the distal 1 cm of their prongs deployed. Radiofrequency ablation was performed in the groups with (n=12 rabbits) and without (n=12 rabbits) the Pringle maneuver. Three animals of each group were sacrificed immediately, three days (the acute phase), seven days (the early subacute phase) and two weeks (the late subacute phase) after RF ablation. The ablation zones were excised and serial pathologic changes in the hepatic vessels, bile ducts and liver parenchyma surrounding the ablation zone were evaluated.

Results: With the Pringle maneuver, portal vein thrombosis was found in three cases (in the immediate [n=2] and acute phase [n=1]), bile duct dilatation adjacent to the ablation zone was found in one case (in the late subacute phase [n=1]), infarction adjacent to the ablation zone was found in three cases (in the early subacute [n=2] and late subacute [n=1] phases). None of the above changes was found in the livers ablated without the Pringle maneuver. On the microscopic findings, centrilobular congestion, sinusoidal congestion, sinusoidal platelet and neutrophilic adhesion, and hepatocyte vacuolar and ballooning changes in liver ablated with Pringle maneuver showed more significant changes than in those livers ablated without the Pringle maneuver (p < 0.05)

Conclusion: Radiofrequency ablation with the Pringle maneuver created more severe pathologic changes in the portal vein, bile ducts and liver parenchyma surrounding the ablation zone compared with RF ablation without the Pringle maneuver. Therefore, we suggest that RF ablation with the Pringle maneuver should be performed with great caution in order to avoid unwanted thermal injury.

Show MeSH
Related in: MedlinePlus