A sonohysterography, also known as a hysterosonography or SIS procedure, is a non-invasive way for doctors to look at the inside of your uterus using sound waves. It’s becoming increasingly important in diagnosing and evaluating a range of gynecological issues, including abnormal bleeding and infertility.
So, what exactly is a SIS procedure, and why might your doctor recommend one? This guide will walk you through everything you need to know, including how it’s performed, what it’s used for, the benefits it offers, and any potential risks or limitations to keep in mind.
Understanding Sonohysterography: What and Why
Sonohysterography, sometimes shortened to SIS, is a type of ultrasound that gives doctors a better look at the lining of your uterus, called the endometrium, and the space inside your uterus.
During the procedure, your doctor will use a small tube to put some sterile saline solution into your uterus, which opens up the space and makes it easier to see during the ultrasound.
While a regular transvaginal ultrasound can give your doctor some information about your uterus, SIS provides a more detailed view because of the saline solution.
Why is Sonohysterography performed?
There are a few reasons why your doctor might recommend that you undergo SIS, including:
- To investigate unexplained vaginal bleeding
- To evaluate uterine abnormalities, such as polyps, fibroids, adhesions, or masses
- As part of an assessment for infertility or recurrent miscarriages
- To evaluate the endometrium after treatment with tamoxifen
- To investigate suspected congenital uterine anomalies
How to prepare for a SIS
If your doctor recommends a saline infusion sonohysterography, you’ll need to schedule it carefully and follow their instructions.
Timing the procedure
It’s important to have a SIS at the right time in your cycle. Doctors usually schedule it right after your period or within the first 10 days of your cycle. This is because it lowers the small chance of doing the procedure while you’re pregnant and because it makes it easier to see the lining of your uterus.
What to do before the procedure
- Tell your doctor if you think you might be pregnant.
- Wear loose, comfortable clothes.
- Don’t wear any jewelry.
Pain Management
You may want to take an over-the-counter pain reliever like ibuprofen (Advil, Motrin) or acetaminophen (Tylenol) before the procedure. This can help with any discomfort.
The SIS Procedure: A Step-by-Step Guide
If your doctor has recommended a saline infusion sonohysterogram (SIS), you may want to know more about what to expect. Here’s a breakdown of how the procedure typically unfolds:
Equipment and Setup
The SIS procedure requires a few specialized tools, including:
- A transvaginal ultrasound probe
- A speculum, similar to what’s used during a Pap smear
- A thin catheter for infusing the saline solution
- Sterile saline solution
The procedure is performed in a sterile environment to minimize the risk of infection.
Procedure Steps
- Initial Transvaginal Ultrasound: First, the technician will perform a baseline transvaginal ultrasound to get a clear picture of your uterus and ovaries before the saline is introduced.
- Catheter Insertion: Next, a speculum will be inserted to help the doctor or technician visualize your cervix. A thin catheter is then gently inserted through the cervix and into your uterus.
- Saline Infusion: Sterile saline solution is slowly infused through the catheter and into your uterine cavity. This fluid gently expands the cavity, allowing for better visualization of the uterine lining and any abnormalities that may be present.
- Real-Time Ultrasound Imaging: As the saline is infused, the ultrasound probe is used to capture real-time images of your uterus. The sonographer will carefully move the probe to obtain different views, ensuring a comprehensive assessment.
- Doppler Ultrasound (if applicable): In some cases, Doppler ultrasound may be used to assess blood flow within the uterus and pelvic region. This can provide additional information about the health of your uterine tissues.
What to Expect During and After the Procedure
An SIS is a quick, relatively painless procedure. Here’s what you can expect.
During the Procedure
Most women report that an SIS feels similar to a routine gynecological exam, like a Pap smear. You might feel a little pressure or discomfort as the speculum is inserted and the catheter is placed. You may experience some cramping as the saline is infused into your uterus. Fortunately, the procedure itself only takes a few minutes.
After the Procedure
After the SIS, it’s normal to have some light spotting or bleeding. You may also have some mild cramping, similar to period cramps, for a short time.
Here are a few things to keep in mind as you recover:
- Use sanitary pads instead of tampons to manage any bleeding.
- If you have any discomfort, over-the-counter pain relievers like ibuprofen (Advil, Motrin) or acetaminophen (Tylenol) can help.
- Your doctor will likely recommend that you avoid sexual intercourse for a day or two to allow your body to heal.
If you experience heavy bleeding, severe pain, or signs of infection (such as fever or foul-smelling discharge), contact your doctor right away.
Interpreting the Results and Follow-Up
A radiologist or a specially trained sonographer will analyze the ultrasound images. They’re looking for anything unusual about the lining of your uterus or the shape of the uterine cavity. They may be able to spot polyps, fibroids, or other growths.
The radiologist sends a report to the doctor who ordered the SIS procedure. That doctor will then discuss the findings with you and advise you about what to do next.
Depending on what the SIS reveals, your doctor might recommend further tests. These could include a hysteroscopy (where a tiny camera is used to look inside your uterus) or a biopsy (where a small sample of tissue is taken for examination).
Benefits and risks of sonohysterography
Like any medical procedure, a sonohysterography has both potential benefits and risks.
Benefits
- Minimally invasive. Compared to more invasive procedures like hysteroscopy or laparoscopy, a SIS is considered a minimally invasive way to diagnose potential problems.
- Accurate diagnosis. Sonohysterography is an effective method for finding uterine abnormalities, such as polyps, fibroids, and adhesions.
- No ionizing radiation. Because a SIS uses ultrasound, you won’t be exposed to any ionizing radiation.
- Outpatient procedure. Most SIS procedures are performed on an outpatient basis, which means you’ll be able to go home the same day.
Risks
- Infection. Infection is a possible, though rare, complication. One large study found that infection occurred in less than 1% of cases.
- Discomfort. Some cramping and spotting are possible during and after the procedure.
- Allergic reaction. In rare cases, people have had an allergic reaction to the saline solution.
- Uterine perforation. Uterine perforation is a very rare risk.
What are the limitations of a SIS?
A SIS is a useful tool, but it does have some limitations.
Cervical Stenosis or Uterine Scarring
If you have cervical stenosis (a narrowing of your cervical canal) or a lot of scar tissue in your uterus, it may be difficult for your doctor to perform the procedure.
Inability to Visualize Fallopian Tubes
A SIS focuses on the inside of your uterus. If your doctor needs information about your fallopian tubes, they will likely recommend a hysterosalpingography (HSG) instead. An HSG uses dye and X-rays to examine the fallopian tubes.
Not Definitive for All Conditions
While a SIS can show abnormalities, it doesn’t always provide a clear diagnosis. Depending on what the SIS shows, your doctor may recommend more tests. These could include a hysteroscopy (a procedure to directly view the uterus) or a biopsy (taking a tissue sample for testing).
Closing Thoughts
The saline infusion sonohysterogram (SIS) is a valuable diagnostic tool for women’s health. It’s minimally invasive, doesn’t expose you to radiation, and is highly accurate in detecting abnormalities of the uterus.
If your doctor recommends an SIS, be sure to discuss any questions or concerns you may have. While the procedure is generally safe and well-tolerated, understanding what to expect can ease any anxiety.
With its ability to provide detailed images of the uterine cavity, the SIS plays a crucial role in helping women maintain their reproductive health.