Laparoscopic radiofrequency ablation of hepatic cavernous hemangioma. A preliminary experience with 27 patients.

BACKGROUND: Radiofrequency ablation (RFA), currently used extensively for liver tumors, also has been applied successfully to hepatic cavernous hemangioma (HCH) percutaneously. The aim of this study was to assess the feasibility, safety, and efficacy of laparoscopic RFA for patients with HCHs. METHODS: Between March 2001 and March 2004, 27 patients with symptomatic and rapid-growth lesions were treated by laparoscopic RFA using the RF-2000 generator system. The treatment-related complications were observed. All the patients were followed up with helical computed tomography scans and ultrasonography at regular intervals to assess the therapeutic efficacy of laparoscopic RFA. RESULTS: This study assessed 9 men and 18 women with a mean age of 41.6 +/- 8.3 years. Three additional intrahepatic lesions missed preoperatively were found in three patients on intraoperative ultrasound. A total of 27 patients with 50 liver lesions were treated successfully with laparoscopic RFA. The mean maximum tumor diameter was 5.5 +/- 2.0 cm. The mean length of time for RFA per lesion was 20.7 +/- 11.9 min, and the mean blood loss was 134.4 +/- 88.9 ml. Laparoscopic cholecystectomy was performed simultaneously for gallstones in 13 patients and for abutting of gallbladder from hemangioma in 2 patients. In addition, 3 patients also had a laparoscopic deroofing of simple hepatic cysts. Although postoperative low-grade fever and transient elevation of serum transaminase levels were observed in 13 patients, there were no complications related to laparoscopic RFA. During a median follow-up period of 21 months (range, 12-42 months), complete lesion necrosis was achieved for all the patients. CONCLUSIONS: Laparoscopic RFA therapy is a safe, feasible, and effective treatment option for patients with symptomatic and rapid-growth HCHs located on the surface of the liver or adjacent to the gallbladder. Intraoperative ultrasonography is a useful adjunct for detecting additional liver lesions and offering more accurate targeting for RFA.

The preclinical pharmacologic study of dopamine transporter imaging agent [99mTc]TRODAT-1.

The purpose of this study was to investigate the pharmacologic characteristics of TRODAT-1 (2beta-((N,N'-bis(2-mercaptoethyl)ethylene diamino)methyl), 3beta-(4-chlorophenyl)tropane) labeled with [99mTc] as an imaging agent for dopamine transporter (DAT). Radiochemical purity of [99mTc]TRODAT-1 was over 90%. The partition coefficients in octanol and buffer were 2.12 and 2.19 at pH 7.0 and 7.4, respectively. Animal studies have been performed in rats, rabbits, and normal and hemi-Parkinsonian model monkeys. Biodistribution displayed moderate uptake in rat brain (0.28 %ID/organ at 2 min) and the striatal uptake was 0.193, 0.142, and 0.136 %ID/g at 2, 60, and 120 min, respectively. The ratios of striatal/cerebellar (ST/CB) uptake were 2.4, 4.45, and 2.45 %ID/g at 60, 120, and 240 min, respectively. The major radioactivity was excreted by the hepatobiliary system. Blood clearance kinetics was performed in rabbits, and the initial half-life of 1.18 min and late half-life of 367.8 min were obtained. Brain single photon emission computed tomography imaging studies in normal monkeys showed the ratios of ST/CB uptake were 1.56-2.0 %ID/g and indicated that both uptake and retention in the striatal area were associated with the DAT. The imaging of hemi-Parkinsonian model monkeys also displayed the expected selectivity, the highest uptake being observed in the basal ganglia area of the normal side. Thereby, it is suggested that [99mTc]TRODAT-1 is a safe and useful imaging agent for localization of the presynaptic DAT in the brain.

Pharmacology study of the neutral myocardial imaging agent technetium-99m-N(NOEt)2.

OBJECTIVE: The biological properties of a new neutral myocardial imaging agent 99mTcN(NOEt)2 were evaluated. METHODS: Blood clearance in rabbits, biodistribution in rats, and initial myocardial imaging in dogs were performed. RESULTS: Radiochemical purity of 99mTcN(NOEt)2 was more than 90% and stable for 6 h at room temperature. Blood disappearance was analyzed with a biexponential model and T1/2(alpha) = 2.53 min, T1/2(beta) = 330 min and CI = 378 ml/h were obtained. Biodistribution studies demonstrated that 99mTcN(NOEt)2 localized selectively in the rat myocardium. Cardiac uptakes were 4.69, 4.20, 3.95 and 3.43% ID/g at 5, 30, 60 and 90 min postinjection, respectively. The mean heart-to-lung activity ratios were 1.69, 2.40 and 2.55 at 10 min, 30 min and 60 min postinjection, respectively. CONCLUSION: Technetium-99m-N(NOEt)2 exhibited favorable stability and biological properties. Further study in humans is required.