J Vasc Interv Radiol

Percutaneous radiofrequency tissue ablation: does perfusion-mediated tissue cooling limit coagulation necrosis?

Goldberg SN. Hahn PF. Tanabe KK. Mueller PR. Schima W. Athanasoulis CA. Compton CC. Solbiati L. Gazelle GS.
Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
PURPOSE: To determine, by decreasing hepatic perfusion during radiofrequency (RF) ablation, whether perfusion-mediated tissue cooling can explain the reduced coagulation observed in in vivo studies compared to that seen with RF application in ex vivo tissue. MATERIALS AND METHODS: RF was applied in vivo with use of cooled-tip electrodes to normal porcine liver without (n = 8) and with balloon occlusion of the portal vein (n = 8), celiac artery (n = 3), or hepatic artery (n = 2), and to ex vivo calf liver (n = 10). In vivo trials of vasopressin (0.3-0.6 U/min) infusion during RF application with (n = 10) and without (n = 2) arterial balloon occlusion were also performed. Intraoperative RF was subsequently performed in seven patients with hepatic colorectal metastases with and without portal inflow occlusion. Remote thermometry was performed in four patients. RESULTS: RF application (12 minutes) during portal venous occlusion produced larger areas of coagulation necrosis than RF with unaltered blood flow (2.9 cm +/- 0.1 vs 2.4 cm +/- 0.2 diameter; P < .01). With celiac and hepatic artery occlusion, coagulation diameter measured 2.7 cm +/- 0.2 and 2.5 cm +/- 0.1, respectively. Infusion of vasopressin without vascular occlusion reduced coagulation diameter to 1.1 cm. However, different methods of hepatic or celiac arterial balloon occlusion with simultaneous vasopressin infusion produced a mean 3.4 cm +/- 0.2 of necrosis. Coagulation in ex vivo liver was 2.9 cm +/- 0.1 in diameter. Clinical studies demonstrated greater coagulation diameter for metastases treated during portal inflow occlusion (4.0 cm +/- 1.3) than for tumors treated with normal blood flow (2.5 cm +/- 0.8; P < .05). Thermometry documented a 10 degrees C increase compared to baseline at 10 mm and 20 mm from the electrode after 5 minutes of portal inflow occlusion during constant RF application. CONCLUSIONS: Perfusion-mediated tissue cooling reduces coagulation necrosis achievable with RF ablation. Reduction of blood flow during RF application increases coagulation in both an animal model and human liver metastases.

Portal venous thrombosis: percutaneous therapy and outcome.

Walser EM. NcNees SW. DeLa Pena O. Crow WN. Morgan RA. Soloway R. Broughan T.
Department of Radiology, The University of Texas Medical Branch, Galveston, USA.
PURPOSE: To study the efficacy of percutaneous treatment for portal vein thrombosis (PVT). MATERIALS AND METHODS: Of 20 patients who were evaluated for symptomatic portal occlusion, 14 were successfully treated with use of percutaneous techniques. In patients with noncavernomatous PVT (n = 15), the initial treatment was to increase portal output by creating a transjugular intrahepatic portosystemic shunt (TIPS), which was successful in 12 cases. Methods to decrease arterial input to the portal system (hepatosplenic arterial embolization) were used as primary therapy in two patients and in an additional two patients with continued symptoms, despite a functioning TIPS. RESULTS: All TIPS survivors had patent shunts, although patients with complete PVT required more frequent revisions compared to patients with nonocclusive PVT. Hepatosplenic arterial embolization controlled symptoms in the four patients who were treated, but both patients with patent TIPS died of liver failure after embolization. Of the 14 patients treated, eight died at a mean of 6.2 months (six from hepatoma). CONCLUSION: TIPS is effective in patients with noncavernomatous PVT, although patients with complete thrombosis experience recurrent shunt occlusions and also may develop hepatoma. If TIPS fails, or if symptoms recur, hepatosplenic arterial embolization may be an option.

Effects of transjugular intrahepatic portosystemic shunts on hepatic metabolic function determined with serial monitoring of arterial ketone bodies.

Terasaki M. Patel NH. Helton WS. Coldwell DM. Althaus SJ. Morimoto T. Yamaoka Y. Ozawa K. Nelson JA.
Department of Radiology, University of Washington School of Medicine, Seattle, USA.
PURPOSE: To investigate the effects of transjugular intrahepatic portosystemic shunt (TIPS) on hepatic metabolic function by measuring serial arterial ketone body ratio (acetoacetate/-hydroxybutyrate; AKBR). MATERIAL AND METHODS: The arterial blood of 30 TIPS patients was assayed before TIPS, 30 minutes after TIPS, and 24 hours after TIPS for acetoacetate, beta-hydroxybutyrate, and glucose. The authors compared the AKBR values to clinical outcome stratified by Child class, emergent versus elective TIPS, and before-TIPS AKBR value < or = 0.5 versus before-TIPS AKBR value > 0.5. RESULTS: A significant change was noted between the AKBR values obtained before TIPS and values 30 minutes after TIPS (0.76 +/- 0.09 vs 0.61 +/- 0.05, P < .05) and between 30 minutes and 24 hours after TIPS (0.81 +/- 0.10, P < .001), but not between the value obtained before TIPS and that obtained 24 hours after TIPS. The 30-day mortality rate in emergency TIPS patients was 50% compared to 7% in the elective TIPS patients (P < .01). The pre-TIPS AKBR values were significantly suppressed in the emergency TIPS patients compared to the elective TIPS patients (0.56 +/- 0.04 vs 0.99 +/- 0.17, P < .005). The 30-day mortality rate in patients with a pre-TIPS AKBR value < or = 0.5 was 75%, which was significantly higher than the 14% rate in patients with a pre-TIPS AKBR value > 0.5 (P < .01). CONCLUSION: A low pre-TIPS AKBR may be predictive of poor outcome after TIPS. Furthermore, AKBR may be of value in determining the timing for performing an elective TIPS.

Complications and technical limitations of hepatic arterial infusion catheter placement for chemotherapy.

Year 1998
Habbe TG. McCowan TC. Goertzen TC. Leveen RF. Culp WC. Tempero MA.
Department of Radiology, The University of Nebraska Medical Center, Omaha 68198-1045, USA.
PURPOSE: To determine the rate of complications associated with hepatic arterial infusion (HAI) catheter placement, as well as technical success related to liver perfusion. MATERIALS AND METHODS: The authors reviewed 44 patients who underwent 106 HAI catheter placements, including 15 men and 29 women with an average age of 55 years (range, 32-82 years). One to nine placements were performed per patient with 61 (58%) via the left brachial artery, 40 (38%) via the right femoral artery, and five (4%) via the left femoral artery. Chemoinfusion lasted 4 days, with initial catheter placement assessed on technetium-99m macroaggregated albumin (MAA) perfusion scans, as well as daily abdominal radiographs. RESULTS: One hundred attempted hepatic arterial catheter placements were completed. Liver perfusion was global in 66 (66%) cases, in the right lobe only in 28 (28%) cases, and in the left lobe only in six (6%) cases. Eight (8%) had gastrointestinal (GI) tract perfusion; this was eliminated in seven cases (7%) after catheter repositioning. Forty-six (43%) placement attempts required embolization of 62 GI vessels to preclude GI chemoinfusion. Complications included one cerebrovascular accident (related to removal of a left brachial catheter), eight brachial artery thromboses (four that required emergent thrombectomy), six hepatic arterial dissections, four hepatic arterial thromboses, and four catheter malfunctions. CONCLUSIONS: HAI catheter placement via the left brachial artery has increased complications. Nearly one-half of placements required embolization of GI vessels to preclude GI perfusion. Global perfusion is possible in two-thirds of cases.

Transcatheter oily chemoembolization of the inferior phrenic artery in hepatocellular carcinoma: the safety and potential therapeutic role.

Year 1998
Chung JW. Park JH. Han JK. Choi BI. Kim TK. Han MC.
Department of Radiology, Seoul National University College of Medicine, Korea.
PURPOSE: To evaluate the efficacy and safety of transcatheter oily chemoembolization therapy (TOCE) via the inferior phrenic artery (IPA) in hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Fifty patients with HCC underwent a total of 82 procedures of TOCE of the IPA, as well as of the hepatic artery. In 16 patients, additional extrahepatic collaterals were depicted and were also embolized in 10 patients. TOCE was performed with an emulsion of iodized oil and doxorubicin hydrochloride, and gelatin sponge particle embolization was added in 32 patients. RESULTS: Initial response showed complete or partial remission of the tumor in 31 patients. The cumulative survival rates after combined TOCE of the hepatic artery, IPA, and other extrahepatic arteries were 89% (6 months), 78% (1 year), 46% (2 year), and 30% (3 year), when calculated from the time of IPA chemoembolization. Liver abscess and empyema developed in one case of combined IPA and multiple intercostal artery chemoembolization. There were no serious complications after IPA chemoembolization alone. CONCLUSION: TOCE of the IPA has a potential therapeutic role as a safe adjunct to TOCE of the hepatic artery in the management of HCC supplied by the IPA.

Subsegmental transcatheter arterial embolization for hepatocellular carcinoma in the caudate lobe.

Year 1998
Terayama N. Miyayama S. Tatsu H. Yamamoto T. Toya D. Tanaka N. Mitsui T. Miura S. Fujisawa M. Kifune K. Matsui O. Takashima T.
Department of Radiology, Fukuiken Saiseikai Hospital, Fukui, Japan.
PURPOSE: To clarify the effectiveness of transcatheter arterial embolization (TAE) for hepatocellular carcinoma (HCC) in the caudate lobe of the liver. MATERIALS AND METHODS: Thirteen patients with HCC in the caudate lobe underwent TAE. TAE was performed by injection of the mixture of anticancer drugs (mitomycin C and doxorubicin or epirubicin) and iodized oil, followed by gelatin sponge particles. Arterial anatomy of the caudate branch, local recurrence rate, and survival rate were evaluated. RESULTS: From 31 TAEs for the caudate lobe, 22 subsegmental TAEs were successfully performed (71%). Local recurrence in the caudate lobe was seen in 10 patients (77%). Subsegmental TAE for the caudate lobe was repeated one to five times. Cumulative local recurrence rates were 33% and 75% within 3 and 6 months, respectively. Survival rates after first TAE for HCC in the caudate lobe were 89% and 74% for 1 and 3 years, respectively. CONCLUSION: Local recurrence rate after subsegmental TAE for HCC in the caudate lobe was high. However, repeated subsegmental TAE possibly improves the prognosis of HCC in the caudate lobe.