Laparoscopically Delivered HIFU for Partial Renal Ablation

摘要

Our purpose is to develop a high intensity focused ultrasound (HIFU) probe to ablate kidney laproscopically. A Sonablate~(TM) 200 HIFU system (Focus Surgery Inc., Indianapolis, IN) was used in acute (n=10) and chronic (n=5) experiments to ablate Yucatan mini-pigs' kidneys. A 5 Fr ureteral catheter was inserted into the renal pelvis and 10 cc of air was instilled into the kidney. The HIFU probe was inserted through a 30-mm trocar placed at the level of the umbilicus. The targeted renal pole was treated aiming to ablate a 21x17x10 mm~3 tissue volume. HIFU induced average lesion size of 23x17x11 mm~3. 10 animals were sacrificed at 4 days and 5 animals at 15 days following surgery. Gross and microscopic examination revealed homogenous and complete tissue necrosis throughout the entire volume of the lesion with sharp demarcation from adjacent normal tissue. We were able to refine a 15mm probe for laparoscopic HIFU delivery capable of simultaneous ultrasonic imaging. Partial renal ablation using this probe is feasible and safe, and results in homogenous, complete and reproducible lesions.