SpaceOAR Hydrogel insertion involves the placement of an absorbable gel between the prostate and rectum, to increase the physical separation between the organs, and thereby reduce the radiation exposure to the rectum during external beam radiation treatment for prostate cancer.

After numbing the area, about 10ml of gel material is injected with a needle passed through the skin behind the scrotum under ultrasound guidance during a brief office procedure. The gel creates an additional 1cm separation between the organs and is absorbed by the body after several months following the conclusion of radiation treatments. The procedure is not appropriate for men with high risk or locally advanced prostate cancer due to the risk of displacing cancer cells.

When to Ask a Urologist about SpaceOAR Hydrogel

You should speak with a Urologist about SpaceOAR Hydrogel if you have chosen external beam radiation therapy as the primary treatment for your prostate cancer.


Typically covered by most insurances (although coinsurance and deductibles may apply). Coverage will be verified prior to proceeding. If you do not have insurance, our office will be able to give you an out-of-pocket cost estimate.


Clinical trials have demonstrated a decreased radiation dose to the rectal wall and 66% improvement in bowel bother in men that received SpaceOAR Hydrogel prior to external beam radiation relative to men that did not.

Possible Side Effects

The risks of SpaceOAR Hydrogel insertion include pain, bleeding, infection, urinary retention, fecal urgency, and needle injury to the bladder, rectum or prostate. The SpaceOAR Hydrogel may be positioned incorrectly or may move after placement and cause displacement of prostate cancer tissue.

Alternative Approaches

No other procedures exist to decrease radiation exposure to the rectum during radiation therapy for prostate cancer. An alternative approach is proceeding with radiation therapy without SpaceOAR Hydrogel placement.

What to do to Prepare for Procedure

You will receive detailed instructions from the surgical schedulers regarding any necessary testing or appointments prior to surgery. In general, you should temporarily stop blood-thinning medications prior to surgery (when to stop depends on the type of blood thinner). Prescription blood-thinning medications should be stopped following clearance from the doctors that prescribed them though other medications that thin the blood including fish oil and pain relievers such as ibuprofen should be stopped as well.

On the day before surgery, you will receive a phone call alerting you to the time that you should arrive.

To limit infection risk, antibiotics are prescribed to start on the day of the procedure. If you do not have a bowel movement that morning, you should perform an enema to remove stool from the rectum. Additional oral medications will be prescribed to limit anxiety and pain that should be taken about one hour before the procedure.

You may bathe, eat, and drink as usual prior to the procedure. You will require a person to drive you to and from the facility due to the pre-procedure medications.

What to Expect after Procedure

The procedure is performed without sedation in the outpatient setting after a local injection of numbing medication. The entire procedure takes about 15 minutes. At the conclusion of the procedure, you may experience mild pain and numbness behind the scrotum as well some urgency to urinate and reduced strength of the urine stream. These symptoms improve over the first few days.