Efficacy of percutaneous radiofrequency ablation of hepatic malignant tumors using a perfused-cooled electrode.

OBJECTIVE: Evaluate the efficacy of percutaneous radiofrequency ablation ofhepatic malignant tumors. MATERIAL AND METHOD: An ultrasound-guided percutaneous radiofrequency ablation using a 17-gauge single needle perfusedcooled electrode (Cool-tip) RF ablation system was performed on 30 hepatic tumors in 26 patients between January 2009 and September 2010. The medical records, CT scan, and MRI results were assessed at one and three months after the procedure was completed. Primary technical success, local tumor progression, and complication were also evaluated. RESULTS: Twenty-six hepatic lesions in 23 patients were primarily hepatocellular carcinoma. Only four lesions in three patients were metastasized. Three of them were from colorectal cancer whilst another one was from malignant melanoma. At 1-month follow-up imaging post percutaneous radiofrequency ablation, complete ablation rate was 86.7%. Local tumor progression at 3-month follow-up imaging was 4.2%. The rate for minor complication was 3.8%. No major complication was found Complete ablation rate was found to increase signiJicantly in tumors size of less than 2 cm compared to those diameter larger than 2 cm (p < 0.05). CONCLUSION: Percutaneous radiofrequency ablation is one of the most effective and invulnerable therapeutic modality in treatment of hepatic malignant tumor. Size is the key factor of technical success as the smaller the size of tumor the better the outcome achieved.

Vascular access stenosis and central vein obstruction interventions: five years of experience in Ramathibodi Hospital.

OBJECTIVE: To evaluate initial post-treatment and six months outcome of patients sent to the intervention radiology unit with vascular access malfunctions. MATERIAL AND METHOD: A retrospective study of venoplasty, venoplasty with stenting, and venoplasty with thrombolysis for vascular access failure patients, included 53 patients with 67 interventional radiology procedures at the intervention radiology unit of Ramathibodi Hospital between January 2004 and June 2009. RESULTS: Sixty-seven intervention procedures were performed in 53 patients. Two patients had severe stenosis of AVF anastomosis with a resulting in failure to perform venoplasty. There were 34 lesions of central venous obstruction. The lesions were usually short and 79% shorter than 4.0 cm. In the group of central venous obstruction that performed venoplasty alone, the degree of stenosis was 58.7 +/- 18.6% (mean +/- SD) with 69.2% technical success and 84.6% clinical successes. However the technical success was increased to 71.4% and clinical success was increased to 100% in the stent placement group. At the six-month follow-up, there was no significant clinical re-obstruction. Fair to good outcomes of interventional procedures of vascular access and peripheral venous stenosis were achieved. Within the group of 14 lesions of patients who underwent AVBG, the degree of stenosis was 64.4 +/- 14.4% with 57.1% technical success and 100% clinical successes. In the other group of 19 lesions that underwent native AVF the degree of stenosis was 61 +/- 9.4% with 52.6% technical success and 89% clinical successes. Two patients had re-stenosis and thrombosis in AVBG six months after treatment procedure. CONCLUSION: Percutaneous interventional radiology procedure continues to play a beneficial role in treatment, and remains the first treatment of choice in vascular access malfunction and corollary complications of central venous obstruction. The technical success rate of treatments is determined by morphologic features of each lesion, with the identification of these features helping in proper planning and the use of appropriate instruments.