Related Experiment Video
Updated: Aug 17, 2026
Generation and Quantitative Analysis of Pulsed Low Frequency Ultrasound to Determine the Sonic Sensitivity of Untreated and Treated Neoplastic Cells
Published on: July 22, 2015
Extracorporeal application of high-intensity focused ultrasound for prostatic tissue ablation
Axel Häcker1, Kai Uwe Köhrmann, Walter Back
1Department of Urology, University Hospital Mannheim, Faculty of Clinical Medicine Mannheim, Ruprecht-Karls-University of Heidelberg, Germany. axel.haecker@chir.ma.uni-heidelberg.de
Objective:
To investigate the efficacy and safety of extracorporeal prostatic tissue ablation using high-intensity focused ultrasound (HIFU) in vivo in animals, and in a clinical feasibility study in men, as this is an investigational minimally invasive treatment alternative for locally confined prostatic carcinoma, but may have significant side-effects.
Patients, Materials And Methods:
Ultrasound (1.04 MHz excitation frequency) was generated by an extracorporeal cylindrical piezo-ceramic element and focused by a paraboloidal reflector to a focal size of 32 x 4 mm. The focal distance and aperture diameter were both 100 mm. HIFU was applied extracorporeally at different intensities and pulse duration (up to 6 s) to 11 dog prostates in vivo (median intensity 1192 W/cm2) and eight patients (median intensity 3278 W/cm2, range 2384-3576) under general anaesthesia. The lesions were assessed macroscopically and histologically after HIFU and any side-effects evaluated.
Results:
Thermoablation was feasible in vivo and in all patients. Macroscopic analysis and histology showed sharply demarcated coagulative necrosis. Side-effects, including skin and rectal burns, occurred only after transvesical application in the in vivo study. There were no side-effects in patients after perineal application.
Conclusion:
Extracorporeal HIFU is technically feasible and induces sharply demarcated tissue damage in the prostate. From the early results of this phase 1 study, the perineal approach seems to be safe.
