A shock wave is a wave of energy that travels faster than the
speed of sound. Urologists commonly apply the energy, during shock wave
lithotripsy, to break up kidney stones.
But when directed
at a scarred penis, the therapy is different.
waves used for erectile dysfunction use about one-tenth of the energy of
traditional shock wave machines for kidney stones. And rather than break
something down, as is the case with stones, shock waves make the penis
healthier, according to Ranjith Ramasamy, MD, director of male reproductive
urology at the University of Miami.
“Stay tuned. It’s
exciting,” said Arthur L. Burnett, MD, MBA, professor of urology at Johns
Hopkins University School of Medicine, Baltimore. “But it would be good to
study it enough to make sure we’re providing good care to patients.”
ED is extremely
prevalent, according to Irwin Goldstein, MD, director of San Diego Sexual
Medicine and director of sexual medicine at Alvarado Hospital in San Diego.
and horribly bothersome and distressing. It affects mood. It affects ego. It’s
frustrating to the partner, and the man feels not a man anymore,” he said.
While ED causes
vary, a common cause, and the focus for shock wave therapy, is when the
erectile tissue becomes so scarred that during the process of muscle
relaxation, the subtunical space can’t close because the tissue is no longer
erectile tissue can’t expand against the tunica, thereby closing down the
subtunical space, thereby compressing the subtunical venules,” Dr. Goldstein
said. “Then, during an erection, blood will leave, like air does when there’s a
nail in a tire.”
treatment with phosphodiesterase type-5 (PDE-5) inhibitors has long been the
first-line treatment among urologists and other providers since their launch in
the late 1990s. If oral agents aren’t successful, men have the options of
prostaglandin E1 injection therapy, a vacuum erection device, intraurethral
suppository treatment, or a penile implant.
treatment often works, but medication leaves a big ED treatment void: disease
modification. That’s important, Dr. Goldstein says, because pharmacologic
treatments can stop working with age, and many men don’t want to take
medications for the rest of their sexual lives.
“We need ways to
get rid of the scar tissue and return muscle back to the patient,” Dr.
physicians recognize that while PDE-5 inhibitors remain a treatment for ED, the
medications don’t enable a man to be natural and functional with natural
erectile ability, according to Dr. Burnett.
“I think [shock
wave therapy] does address that. It’s almost curative. [If approved,] we can
offer something that can heal the penis and maybe allow natural responses,” Dr.
Low-intensity shock wave therapy is currently one of three
experimental disease modification strategies to help restore erectile tissue
health. The other two are stem cell infusion and the use of platelet-rich
Dr. Goldstein said his site will begin recruiting in December
for a trial looking at use of stem cells for erectile dysfunction. The
treatment, which uses mesenchymal stem cells, requires liposuction to obtain
needed fat cells and a trip to the operating room for the stem cell infusion.
PRP, he said, is widely used in sports medicine and orthopedics. The problem
is, the therapy is largely uncontrolled in the U.S.
“It’s the Wild
West. But that shouldn’t distract from the fact that PRP is a fabulous
material. It should be undergoing FDA trials with a robust placebo arm, but it
isn’t,” Dr. Goldstein said.
Enter shock wave therapy
The movement to
make shock wave therapy a credible and widespread ED option is well on its way.
In a systematic
review and meta-analysis published in 2017, Dr. Ramasamy and colleagues
analyzed the use of low-intensity extracorporeal shock wave therapy in seven
randomized controlled trials, with a total of 602 patients. They found among
men with an average age of 60.7 years and an average follow-up of 19.8 weeks,
International Index of Erectile Function score significantly improved an
average 6.40 points from baseline in men receiving shock wave treatment,
compared to an average 1.65 points in those receiving sham therapy (J Sex Med 2017; 14:27-35).
Devices are being
studied in clinical trials, and shock wave therapy to treat ED is already being
marketed. Aventura, FL-based Sexual MD Solutions markets the GAINSWave therapy
brand to enhance sexual performance and optimize erection quality through a
network of more than 100 trained providers. According to the company, certified
GAINSWave providers must follow specific protocols and are required to use a
medical device that is FDA cleared for other indications, including localized
improvement of blood flow.
Bruce Sloane, MD, a urologist in private
practice in Philadelphia, whose solo practice focuses on men’s health, offers
the GAINSWave procedure and said it has shown good results in treating ED.
“I’ve had some men in their 30s who are diabetic and men in
their 80s. Some [responses] are more dramatic than others. But every man has
improvement in the quality of their erections,” said Dr. Sloane, who had
treated about 50 patients when interviewed by Urology Times. “I
have a couple men with severe erectile dysfunction who were only getting
erections after penile injection therapy. I treated them with 12 sessions of
the GAINSWave therapy, and they now only have to use medication. They’re off
There are two theories about how shock waves work to treat ED,
according to Dr. Ramasamy. One relates to neo-angiogenesis at penile tissue;
the shock waves create injury and, therefore, create new blood vessels that
will help treat vasculogenic erectile dysfunction. The second theory is that
shock wave therapy improves ED by recruiting stem cells, which helps with
growth of new corporal and penile tissue.
Dr. Goldstein said he thinks low-intensity shock wave therapy
works by activating stem cells.
“The shock wave
provides an energy to the stem cells, and the stem cells get activated and
grow—growing muscle, blood vessels,” said Dr. Goldstein, whose practice is
among the U.S. sites conducting a placebo-controlled trial on use of
low-intensity shock wave therapy for ED with the Dornier device.
Finding that ideal protocol
Just how to use
it for ED—how many shocks to deliver, how often, and for how long—remains
largely unanswered. Urologists and others in the U.S. need data to make
low-intensity shock wave therapy clinically useful and safe, Dr. Goldstein
protocols, the danger exists that the therapy might not be as effective or
effective at all, according to Dr. Burnett.
“You still want
to be credible. You want to offer therapy that patients feel good about
spending their resources and money to obtain,” Dr. Burnett said.
At the moment,
there is no single gold-standard protocol.
In a recently
published meta-analysis looking at low-intensity extracorporeal shock wave
therapy for ED, Chinese researchers analyzed nine studies, including 637
patients, from 2005 to 2017. They found that low-energy extracorporeal shock
wave therapy could significantly improve patients’ International Index of
Erectile Function and Erection Hardness Score, and therapeutic efficacy could
last at least 3 months (Urology Sept. 26, 2017
[Epub ahead of print]). They also reported that lower energy density, at an
average 0.09 mj/mm2; 3,000 pulses per
treatment; and total treatment courses of less than 6 weeks resulted in better
The number of
treatments needed varies, according to Dr. Sloane, who said the basic GAINSWave
protocol is six or 12 treatments, depending on ED severity.
“If a man needs
six treatments, we’ll do two a week for 3 weeks. And the treatments are about
15 minutes each,” Dr. Sloane said.
Dr. Ramasamy, who
has been part of a clinical trial using shock wave therapy with DirexGroup’s
FDA-cleared MoreNova device, said men in the study are receiving a total of
randomized trial with two arms. It’s either every other day, for a total of six
sessions, or every day, for a total of five sessions. The total number of
shocks delivered is basically the same in both arms, and treatments last about
10 minutes each. Then, we follow patients at 1 month, 3 months, and 6 months,”
data, Dr. Ramasamy said men who receive the everyday treatment appear to
respond better than those receiving the every-other-day treatment.
“Men would be
able to have sex as early as the following week [after treatment],” he said.
Dr. Ramasamy and
colleagues have recruited 44 patients so far and will recruit a total of 80.
said his study’s protocol is to administer low-intensity shock wave therapy
once a week for 6 weeks. He tells patients they can have sex the same day or
night as treatment.
“The shock wave
treatment is about 30 minutes and completely pain free,” Dr. Goldstein said.
As for the need for maintenance treatments,
that’s not clear, according to Dr. Ramasamy.
“No one truly
understands how long the effect of these shock waves lasts and what the
long-term effect is. Right now, we have very good data at 3 months and very few
patients at 6 months,” Dr. Ramasamy said.
therapy appears to be safe.
“Patients tolerate it very well,” Dr. Ramasamy said. “There’s
minimal pain. Sometimes, subjects have redness on the skin. But at the doses
that we’re using there is very minimal change that happens to the penis,
shock wave therapy for ED appears to be most suited for men who have mild
erectile dysfunction and who are either responsive or nonresponsive to PDE-5
inhibitors, according to Dr. Ramasamy.
who have not tried Cialis and Viagra respond very well, and men who have tried
and failed Cialis and Viagra, who have received shock waves, appear to go back
to respond to PDE-5 inhibitors,” he said. “I don’t think it’s appropriate for
the man with severe diabetes, severe venous insufficiency, or men who have had
previous pelvic surgeries, such as radical prostatectomy or radical
Goldstein said he agrees that it’s doubtful shock wave therapy will rescue men
in the severe group.
if we follow this over time, we might allow people to never become severe,” Dr.
big advance in ED treatment?
FDA approves shock wave therapy for ED, Dr. Goldstein said he thinks all
urology practices will offer the treatment.
the device and performing the treatment requires little in the way of a skill
set. Nurses can deliver the treatment. But everyone in the room needs to wear
heavy-duty ear protection because the sound from the device can be loud and
physically damaging, especially to those administering low-intensity shock wave
therapy, Dr. Goldstein said.
only disposable required to use the technology is ultrasound gel, which when
rubbed on the penis helps to transmit the shock waves, according to Dr. Sloane.
point is, this will become a pretty widespread treatment of aging men. Most
people will have pretty good erectile function until age 40, 45, 50. Then,
after age 40 or 45, you have a direct falling,” Dr. Goldstein said. “So if you
can change the slope a tiny bit, make it less steep with just getting your
penis shocked, would you do that? When this comes out and it’s shown to be
efficacious, I will be one of the people getting shock wave therapy.”
Burnett is an investigator for Medispec. Dr. Ramasamy is an investigator for
Direx. Dr. Goldstein is a consultant to and researcher for Dornier; researcher for
Tissue Genesis; a member of the speakers’ bureau for Coloplast, Dornier, and
Mist Pharmaceuticals; and provides writing support for Pfizer.