HIFU Procedure for Prostate Cancer
Minimally-Invasive Therapy For Prostate Cancers
The HIFU device is made up of 2 modules – the control module which allows the physician to plan and supervise the computerized system and the patient treatment module.
The control model contains a robotic endorectal probe which is guided by the computerized system. The probe is mounted on a mobile support with robotic movements that enable the computerized device to automatically and precisely move the probe during treatment to treat the targeted areas of the prostate.
After a local or general anaesthetic is administered, the patient lies down on his right hand side (right lateral decubitus) and stays in this position throughout the treatment.
Three Phases Treatment
Patients undergoing Ablatherm® HIFU cancer treatment are given a general or spinal anesthetic. A probe is introduced in the rectum and the imaging transducer starts the gland scanning to plan the treatment. The treatment transducer then emits high intensity focused ultrasound in the prostate gland. At the point where the ultrasound waves are focused the absorption of the ultrasound beam creates a sudden temperature increase (around 185°F) which destroys the tissue in the targeted zone.
1. 3D Imaging
The first phase of the treatment process begins with a high definition scan of the prostate using the 7.5 MHz imaging transducer.
2. Treatment Planning
The urologist then plans the treatment beginning with the localization of the prostate apex and the rectal wall to define the correct lesion height and distance from the rectal wall.
A 3-dimensional image of the prostate is then recreated by the computerized system. The physician uses this picture to plan the treatment and define the area to be treated by the robot. The prostate image is divided into a series of defined blocks and the computer software calculates the appropriate number of lesions. The 3.0 MHz probe calculates an adjustable ablation volume (total volume 29 mm3 to 36 mm3 (anterior to posterior).
3. Robotic Treatment
Once the treatment plan is complete, the shooting phase of the treatment can begin. The prostate can be treated in a single pass with the lesion height range from 19mm to 26mm (anterior-posterior distance). 400 to 800 adjacent lesions are required to cover the entire prostate volume.
The robotic probe then generates a high intensity focused ultrasound beam every 10 seconds to automatically carry out the urologists instructions. The ultrasound beam destroys a very small part of the prostate with extreme precision (to within a few millimeters.)
The tissue in the targeted zones is destroyed with intense, very fast, highly localized heat. Each ultrasound shot is oval shaped, measuring up to 26mm high by 2mm or less in diameter. The process continues until all of the targeted areas are treated. Depending on the volume of the prostate, the treatment can last 2 to 2 ½ hours.
- Rectal cooling
- Patient movement detection
- Real time rectal wall monitoring