1.5T conventional MR-guided iodine-125 interstitial implants for hepatocellular carcinoma: feasibility and preliminary clinical experience.

PURPOSE: To evaluate the feasibility and therapeutic efficacy of 1.5 T conventional MR-guided percutaneous interstitial implantation of I-125 radioactive seeds in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: The institutional ethics committee approved this study. After imformed consent was obtained, twenty-three patients suffering from a total of 65 HCC lesions were treated with I-125 seed permanent interstitial implantation under the guidance of a 1.5T conventional magnetic resonance imaging (MRI) system. The FSE T2WI, T1 FSPGR, FIESTA 2D, 3D Dyn T1WI sequences were used to guide an 18 G MR-compatible needle inserted into the lesions to introduce the I-125 seeds. The response evaluation criteria in solid tumors (RECIST) were used to evaluate the curative effect. RESULTS: The needle and I-125 seed were seen clearly on MRI images. The final dose delivered to total decay was 173.46 ± 32.44 Gy (range, 110-270 Gy) as calculated by postoperative TPS. The complete response (CR) was seen in 22 lesions (33.8%), partial response (PR) in 24 lesions (36.9%), stable disease (SD) in 9 lesions (13.8%), and progressive disease (PD) in 10 lesions (15.4%). The post-operative alpha-fetoprotein (AFP) was decreased (t = 3.117, P = 0.005<0.05). Two patients were observed a small area of subcapsular bleeding that did not lead to any symptoms or clinical sequelae. CONCLUSION: MR-guided I-125 implantation for HCC is technically feasible and effective.

Artificial pneumothorax with position adjustment for computed tomography-guided percutaneous core biopsy of mediastinum lesions.

PURPOSE: This study was designed to assess the use of artificial pneumothorax with position adjustment to gain a pleural space approach in computed tomographic-guided core biopsy of mediastinal masses. DESCRIPTION: Eleven patients with mediastinal lesions who were undergoing percutaneous core biopsies received an artificial pneumothorax with a 22-gauge lumbar puncture needle. Each patient's position was adjusted to place the lesion as high as possible in the thoracic cavity. Air was injected until the lung was displaced from the path of the biopsy needle. After completion of the biopsy, a comparable volume of air was aspirated. EVALUATION: In all patients, satisfactory displacement of the lung from the biopsy site was achieved with the artificial pneuomothorax procedure enabling the target lesion to be reached. No postoperative air leaks requiring tube drainage were encountered. CONCLUSIONS: Artificial pneumothorax with position adjustment is a safe and effective method that provides access for computed tomographic-guided biopsy of mediastinal lesions without the risks of traversing aerated lung tissue and with a relatively low volume of injected air.