Frequently Asked HIFU Questions
HIFU, which stands for high intensity focused ultrasound, is the focusing of sound waves to create heat at a specific point; this is called the focal point. This heat effectively destroys the targeted tissue. HIFU was cleared by the FDA for prostate ablation in October 2015 although it has been available outside the United States for more than 10 years for the treatment of localized prostate cancer and benign prostatic hyperplasia (BPH) or prostate enlargement.
What is the Sonablate®?
The Sonablate® is a non-invasive medical device manufactured by SonaCare Medical, which uses HIFU to ablate tissue which trained physicians can use for treating prostate cancer and BPH. The Sonablate® uses a single transducer to obtain real-time images of the prostate during treatment and provides treatment in zones from top to bottom and from side to side. Sonablate® software allows the surgeon to customize each of the treatment zones to safely ablate the entire gland.
How does Sonablate treat prostate disease?
Using intersecting precision focused ultrasound waves, the device destroys tissue and leaves healthy cells surrounding the prostate unharmed. Unlike radiation, HIFU energy is “clean” energy. This means it can be applied repeatedly (if needed) without causing damage to tissue between the transducer and the prostate.
What are the outcomes of the Sonablate HIFU treatment?
An international study published by Toyaki Uchida, MD (Japan) reported that 94% of patients (low risk) were disease-free after four years. Additionally, 92% of men treated with HIFU had a PSA of .2ng/ML or lower 3 months after HIFU as reported in a study by Dr. Mark Emberton of London.
Does HIFU only treat the cancerous cells?
Sonablate® HIFU will ablate any tissue that the physician targets with the device during treatment planning. After the physician reviews your diagnosis, he or she will make a recommendation on the best course of treatment. This recommendation, based on your pathology report , will include how much of the prostate should be treated. In most cases, the entire prostate will be targeted, which would include the tumor as well as any other tissue in the prostate. Think of it as having the prostate removed, without a single incision. However, some physicians, who work with advanced, MRI- guided imaging for diagnosis, can determine the exact location of the tumor in the prostate and may use HIFU to only treat the tumor leaving other tissue in the prostate intact; this is referred to as focal therapy.
What is the history of HIFU and how long has it been around?
HIFU research began as far back as the 1950s at Indiana University. However, the first human prostate cancer study was conducted in 1994 by Dr. Marberger and Dr. Madersbacher at the University of Vienna in Austria using the Sonablate® 200, treating 29 human prostates in vivo shortly before performing a radical prostatectomy. The goal was to see if the energy delivered was enough to destroy the desired tissue. The study found that treatment could be performed safely and could be repeated.
In 1995, a different study, done at Indiana University showed that the entire prostate could be treated without damaging the prostate capsule or the rectal wall. In 1999, Dr. Toyaki Uchida began treating patients using the Sonablate in Japan. The device received approval for use in Europe with the CE Mark in 2001 and in 2004, treatment became available at hospital and treatment centers in Mexico, Costa Rica, South Africa and the Caribbean. Health Canada approved the Sonablate 500 in June 2005 and the first Sonablate HIFU procedures were performed in Toronto in March 2006.
Currently, there are approximately 300 physicians using the Sonablate worldwide and over 15,000 total procedures have been completed. SonaCare Medical is the manufacturer of the Sonablate and received cleared from the FDA for prostate cancer ablation in October 2015.
How does Sonablate HIFU compare to HIFU with the Ablatherm?
The Sonablate device allows for a more precise and customized treatment than the Ablatherm. Sonablate software allows for smaller treatment zones and adjustable energy delivery, which allow for focal treatments and less risk in damaging important structures such as the urinary sphincter and nerves that are important for erections. Additionally, it is possible to treat larger prostate glands with the Sonablate. Read a detailed comparison of the devices here.
Which features are unique to the Sonablate that are focused on patient safety?
The Sonablate is a highly-sophisticated device that includes numerous features for patient safety including:
Neurovascular bundle detection helps the physician to avoid causing harm to sensitive structures surrounding the prostate, like neurovascular bundles. The ability to avoid a neurovascular bundle can have a significant effect on maintaining erectile function and help to preserve a patient’s quality of life.
- Rectal wall monitoring helps determine the temperature of and proximity to the rectal wall. This helps the physician protect the rectal wall tissue during therapy.
- The active cooling system circulates chilled water through the probe during the procedure while monitoring temperature, which helps the physician protect the rectal wall tissue from heat generated during thermal ablation.
- Real-time imaging allows the physician to view and compare the original image to the real-time image being treated, for visual ablation confirmation.
- MRI/Ultrasound fusion integration software allows the physician to merge MRI images into the Sonablate planning software, fusing them with the real-time ultrasound images. The physician can then determine a more precise ablation plan based on the fusion of these two key datasets.
- TCM or Tissue Change Monitoring is a color display that (during tissue ablation) gives the physician enhanced feedback about the change in tissue at each point of HIFU delivery.
How do I know if I qualify for HIFU?
While only a physician can determine if you qualify for HIFU or not, typically men with a prostate gland of less than 40 grams with localized prostate cancer (tumor has not spread outside of the prostate gland) may be candidates for HIFU. The other information that physicians usually look at to determine if you qualify for HIFU is a PSA of 20 or less and a Gleason score of 7 or less. It is best to talk with a HIFU nurse or doctor to determine if you might qualify for HIFU.
Can I still be treated if I have a large prostate?
Your physician will need to know the exact dimensions of your prostate to know whether or not you are a candidate for HIFU. If your prostate is too large, there may be ways you can work with your doctor to shrink or reduce the size of the gland prior to scheduling a HIFU procedure.
Should I have total gland HIFU or Focal HIFU?
In order to know if you are a candidate for focal HIFU or whole gland ablation, a physician would need to thoroughly review your pathology report as well as ideally have advanced MRI imaging done to determine the exact size and location of your prostate cancer.
Is there a greater chance the cancer will come back if I choose to have a focal treatment versus full gland treatment?
With focal therapy, the physician only treats the area of the prostate that contains the tumor. This is determined after multiple types of diagnostic imaging as well as biopsy reports to confirm the staging of the disease. The procedure is shorter, recovery time is faster and time wearing a catheter is greatly reduced. This means that if after focal HIFU there is an elevation in PSA, and evidence that the cancer has appeared in a different location, the physician can easily go back and deliver HIFU in the new location. Additionally, the patient may choose to have any other type of therapy at that time. This is a much less radical approach to locating the cancer and eliminating it. Prior to having focal HIFU, your physician should thoroughly explain to you the risk of the cancer returning based on your diagnostic reports.
How does HIFU compare to traditional treatments for prostate cancer, including surgery and radiation?
Studies show that HIFU has rates of efficacy similar to other treatments for prostate cancer but with less risk for side effects such as incontinence and erectile dysfunction. HIFU also does not exclude you from having any other treatments, should you have a recurrence of prostate cancer, as other treatments such as surgery and radiation will.
Is HIFU a type of radiation, like brachytherapy?
No, HIFU is completely radiation free. Unlike radiation, HIFU is a clean, or non-ionizing, energy source. This means that it can be repeated as necessary, and will not prevent a patient from pursuing any other treatment options after HIFU. During brachytherapy, radioactive seeds are placed inside the prostate and remain in the prostate after the procedure is complete. Often times, these seeds will migrate to other organs, which can cause additional issues for patients.
What will I need to do to prepare for the HIFU procedure?
Prior to HIFU, patients should have the usual lab work (CBC, Complete Medical Panel, Urinary Analysis with culture, if indicated by your physician) and an EKG in preparation for undergoing anesthesia. If the patient has any significant medical history, he should see his cardiologist or primary physician for clearance for the anesthesia. The HIFU procedure itself causes no significant bleeding or swings in blood pressure, etc. A nurse will send detailed information after the procedure has been scheduled regarding diet, medications and any additional lab work or tests that may be required.
How long does the HIFU procedure take?
The length of the procedure depends on the size of the prostate gland. Larger glands will take longer to treat completely. A way to estimate time is 1 hour for every 10 grams of tissue to be treated. That works out to an average of 1.5- 4 hours.
What happens to the urethra during HIFU? Since it runs through the center of the prostate, is it destroyed during the procedure?
During HIFU, the entire prostate is ablated, including the prostatic urethra. However, the urethra is derived from a different type of tissue (bladder squamous-type epithelium) rather than prostatic tissue (glandular, fibrotic and muscular). While the urethra is an important anatomical structure, the sphincter and bladder neck are more important to maintaining the urinary function.
Is there pain with HIFU? What should I expect?
During HIFU, patients are given anesthesia to minimize any movement during the procedure and to make the patient as comfortable as possible. There should be no pain associated with the procedure although patients may experience various levels of discomfort afterwards.
What type of anesthesia is used for the HIFU treatment?
General anesthesia is the preferred anesthesia during HIFU procedures. It is very important that you and your prostate remain still for the duration of the procedure, and general anesthesia assures that this happens.
What medications will I need after HIFU?
Your HIFU nurse will give you a detailed list of medications you will need to take after your procedure. In general, you may be advised to take an over-the-counter painkiller (Tylenol, Advil etc.) for any discomfort. Additionally, you may be given an antibiotic to reduce any risk of infection post procedure, as well as medication to make your catheter more comfortable. You may also be given medication to help with your urinary stream after HIFU.
What is the recovery time and the side effects of Sonablate HIFU?
Your specific recovery will depend on the stage and location of your disease but in general, recovery involves wearing a catheter; however, most people usually return to most of their normal activities within few days. Immediately following the HIFU procedure, men spend a few hours in recovery at the treatment facility and then are discharged to return home. HIFU patients sometimes experience frequency, urgency, mild discomfort or discharge in urinary stream. Studies performed outside the U.S. report that potential side effects may also include urinary stricture (18%)2, retention (0.6%)1, incontinence (0.6%)1, erectile dysfunction (20%)1 and rectal fistula (1%)1.
What kind of catheter will I have to wear?
Most patients have a suprapubic catheter after HIFU. This is inserted by a physician before HIFU begins and will be in place after the procedure for 1-3 weeks depending on the size of your gland. The catheter allows for your bladder to empty comfortably while your body heals. It is common to have a catheter for some length of time after prostate cancer procedures. If you are having a focal (partial gland) treatment, you may go home with a Foley (urethral) catheter which is typically worn between 5-10 days. The type of catheter you have will be determined by your HIFU physician before your treatment and your HIFU nurse will provide you education on how to care for your catheter.
When can I resume sexual intercourse?
Usually, patients can have sex after their catheter has been removed. You should speak with a physician if you have any questions or concerns about resuming sexual activities.
When can I go back to work/normal activities?
Men may return to office-based work and drive the following day. More intense physical activity resumes in 3-5 days, though no activity should be started that dislodges the catheter or stirs up bleeding from the catheter insertion site. The treated prostate tissue does not bleed, as the blood vessels are sealed by the HIFU energy. If a TURP was done prior to HIFU, no physical exertion should be done until at least one month following the TURP. The TURP exposes blood vessels at the bladder neck that are not exposed to the sealing HIFU energy, and therefore could bleed. Always seek the advice of your HIFU physician before resuming any physical activity after HIFU.
What type of follow-up is there after HIFU?
Follow up after HIFU with your physician will be similar to any other treatment for prostate cancer. A HIFU nurse will call you after your procedure to see how you are recovering and ask if you have any questions and concerns. Additionally, you will need to make an appointment several weeks after your procedure to have your catheter removed and then return for visits at 3 months, 6 months, 9 months, and 12 months to have your PSA tested.
1Five years experience of transrectal high-intensity focused ultrasound using the Sonablate device in the treatment of localized prostate cancer. Toyoaki Uchida, et al. Dept. of Urology University of Tokai Hachioji Hospital. International Journal of Urology 2006.
2 Toyaki U., Shiro B., Akira I., et al., Transrectal high-intensity focused ultrasound in the treatment of localized prostate cancer: A multicenter study.Acta Urol. Jpn. Vol. 51, No. 10, 2005.