Rectal & Anal Ultrasound
Using sound waves to detect tissue abnormalities
Radiation-Free Diagnostic Imaging with Sensitivity and Compassion
Illness and disease can affect your rectum and anus just as they can affect other parts of your body. Ultrasonography, or ultrasound, is an imaging test that can help visualize these areas without radiation. It’s offered through our Radiology Department.
Doctors in the Digestive Disease Center may recommend ultrasound to diagnose or evaluate conditions affecting your rectum or anus. Your rectum is the muscular tube that connects the large intestine to your anus, or opening, where stool leaves your body.
What are Rectal Ultrasound and Anal Ultrasound?
Ultrasound involves the use of sound waves. As the waves bounce off the structures of your body, they create echoes. The echoes are transformed into pictures on a computer screen.
Rectal ultrasound is also known as endorectal ultrasound. Doctors may use this test to evaluate growths in your rectum. When they know the exact location of a mass and how far it's growing into your rectal wall, it helps them plan surgery to remove it.
Doctors also use rectal ultrasound for follow-up care after tumor removal and to look for inflammatory or infectious conditions surrounding your rectum.
If you're having problems such as incontinence or constipation, we may turn to anal ultrasound (endoanal ultrasound) to help us to evaluate anal muscles (sphincters). We also use the test to look for inflammatory and infectious conditions in the area connecting your rectum and anus, such as fistulas. A fistula is a tunnel-like passageway running from inside your anus to your skin.
More About Rectal Ultrasound & Anal Ultrasound
Just before your exam, you have a mini-enema to clean out your rectum. This makes it easier to get clear images. The enema is the only preparation you need.
After you change into a hospital gown, we take you into an exam room. There, we ask you to lie on a table on your left side with your knees bent. We carefully insert a lubricated ultrasound device called a transducer into your rectum. To create the images, we move the device forward and backward. We try to make the exam as comfortable as possible for you in every way we can.
The transducer is about the size of an adult finger. You may experience some discomfort when we first insert it, but any pain is minimal and brief. During rectal exams, once the transducer moves past your anal sphincter, we inflate a water-filled balloon. This helps us get better images.
During an anal ultrasound, the transducer remains in your anal canal, which can be more uncomfortable. Again, the exam is over quickly. Generally, rectal and anal ultrasounds take just 5–10 minutes.
We provide your doctor a report of your ultrasound the day after your exam. You may call your doctor to discuss your results. You may also see a copy of your results in our patient portal.
