Experimental study of contrast enhanced transrectal ultrasound for monitoring radiofrequency ablation of prostate / 中华超声影像学杂志

ABSTRACT

Objective To determine the feasibility and safety of radiofrequeney(RF)ablation of entire prostate guided and monitored by contrast-enhanced transrectal ultrasound(CE-TRUS)in canine model.Methods Contrast ultrasound-guided RF ablation of entire prostate was preformed transrectally using Cool-tiptm electrodes in 7 normal canines under general anesthesia.The urethra/bladder and rectum were protected by infusion of cold distilled water through a Foley catheter and injection of cold distilled water into the prostate-rectum space,respectively.CE-TRUS findings were compared with TTC-stained pathologic results.Results All the 7 canines tolerated the ablation procedures.CE-TRUS clearly demonstrated hypoechoic thermal lesions as avascular/nonperfusion areas.The average number acquired for entire prostate ablation was 4.3(3 to 6).The average ablation volume achieved on pathology was 96.55%.There was no statistically significant difference when compared average ablative volumes between CE-TRUS and TTC-stained pathology[(9.16±5.20)cm3 vs(8.62±3.13)cm3,P=0.583].The coefficient correlation was 0.94(P=0.002).No thermal related injuries were found in anv of the bladder and rectum.The thermal related inj uries of the urethra were less than 1/4 quadrant.Conclusions It is feasible to ablate the entire prostate using RF thermal energy under CE-TRUS guidance.CE-TRUS plays a key role for achieving entire prostate ablation.The urethra and rectum can be protected by cooling of these structures during the procedure.