What is HIFU?
HIFU, which is short for High Intensity Focused Ultrasound, is a state-of-the-art technology acoustic ablation technique that utilizes the power of ultrasound to destroy deep-seated tissue with pinpoint accuracy for treatment of prostate cancer. HIFU focuses sound waves in a targeted area which rapidly increases the temperature in the focal zone causing tissue destruction.
In most cases, HIFU is a 1-4 hour, one-time procedure performed on an out-patient basis under spinal anesthesia. Unlike radiation, HIFU is non-ionizing; this means that HIFU may also be used as a salvage technique if other prostate cancer treatments fail.
How Does HIFU Work Against Prostate Cancer?
In order to understand the basic concept of how HIFU works, an analogy can be drawn between HIFU ablating the prostate and sunrays entering a magnifying glass to burn a leaf. When a magnifying glass is held above a leaf in the correct position on a sunny day the sunrays intersect below the lens and cause the leaf to burn at the point of intersection.
If you insert your hand into the path of either one of the sun rays individually, away from the point of intersection, there is no significant heat felt or harm caused. Alternatively, if you place your hand at the point of intersection you will be burned.
The scientific principles at work in this example are the same as those with HIFU. Instead of light as the energy source, HIFU utilizes sound. Instead of a magnifying glass HIFU uses a transducer. Just as the individual sunray is harmless to the hand, and individual sound wave is harmless to the healthy tissue it travels through.
During HIFU, the physician uses continuously updated real-time images of the prostate to map out and execute the entire treatment plan. These images show treatment progression and permit the physician to customize treatment for maximum safety and effectiveness.
What is the Sonablate® 500 and How Does it Treat Prostate Cancer?
The Sonablate® 500 (SB500) is a minimally invasive medical device, developed by Focus Surgery Inc.(Indianapolis, IN) that uses High Intensity Focused Ultrasound (HIFU) to treat prostate cancer and BPH.
The Sonablate® is the only HIFU device for prostate cancer that does not regularly require a TURP procedure prior to treatment in order to achieve effective results.
The Sonablate® uses a single transducer to obtain real-time images of the prostate during treatment and provide treatment in multiple treatment zones. The Sonablate® software allows the surgeon to customize each treatment zones in order to safely ablate the entire gland.
This image illustrates in the Sector (Transverse) and Linear (Longitudinal) view how the Sonablate® 500 HIFU beam is precisely focused and delivered into the prostate gland. (image courtesy of Takai Hospital Supply Co., Japan)
The technology behind the device originated at Indiana University School of Medicine in Indianapolis in the 1970s. It was further developed in leading research centers across the globe.
Steps to Sonablate® HIFU
- Image & Measure the Prostate: Sophisticated Sonablate software allows physician to image the prostate in both the transverse and sagittal modes in real time.
- Plan Sonablate® HIFU Therapy: Using unique, breakthrough scientific capabilities, the Sonablate® allows physician to create a custom treatment plan for each patient using 2D & 3D images in multiple treatment zones, as well as integrated Neurovascular Bundle Detection. Physicians have flexibility to use either 3 cm or 4 cm transducer to customize each therapy and accommodate prostates with AP diameter of up to 4.0 cm.
- Refine & Customize Treatment Plan: After therapy is planned, it can be refined using 2D & 3D visualization of the prostate and the plan. This makes the procedure precise and completely customizable.
- Start Sonablate® HIFU. Monitor & Adjust During Therapy: With Sonablate® HIFU technology, physicians monitor therapy continuously to ensure patient safety. Doctors may be able to adjust rectal wall distance and energy levels to achieve optimal outcomes.
- Final Review: After each treatment zone is complete, physicians have another opportunity to review the case and add additional treatment if needed. After all treatment zones have sufficiently been treated and reviewed, Sonablate® HIFU is complete.