A saline sonogram (SIS), also known as a sonohysterogram, is a specialized imaging technique used to examine the uterine cavity. It helps identify structural issues affecting reproductive health by providing a clearer view of the uterine lining, often difficult to assess with standard ultrasound. It serves as a diagnostic tool for various gynecological symptoms and conditions.
Defining a Saline Sonogram
A saline sonogram is an ultrasound procedure using sterile saline solution to enhance uterine cavity visualization. A thin catheter is inserted into the uterus, and saline is gently infused. This expands the uterine cavity, allowing ultrasound waves to create a more detailed image of the uterine lining and internal structures than conventional ultrasound. The fluid helps distinguish between uterine walls and any abnormalities like growths or scar tissue. This method uses high-frequency sound waves, similar to standard ultrasound, and involves no radiation.
Reasons for the Procedure
Medical professionals use saline sonograms to investigate various gynecological conditions. It is often performed to evaluate abnormal uterine bleeding, such as heavy or prolonged periods or unexpected bleeding between cycles. The procedure is also a common diagnostic step for infertility or recurrent miscarriages, as it helps identify uterine structural issues that could hinder conception or pregnancy.
A saline sonogram is useful for detecting and characterizing uterine abnormalities. These include endometrial polyps (small growths from the uterine lining), fibroids (benign muscle tumors within the uterine wall), intrauterine adhesions (scar tissue), and congenital uterine anomalies (structural abnormalities present from birth). The detailed view helps guide subsequent treatment decisions.
What to Expect During the Procedure
Preparation involves timing the procedure to the menstrual cycle, ideally between day 5 and day 10, after bleeding stops but before ovulation. This ensures the uterine lining is thinnest for clearest images. Patients are advised to take over-the-counter pain medication, like ibuprofen, an hour before to minimize cramping or discomfort.
The procedure usually lasts 15 to 30 minutes. It begins with a transvaginal ultrasound for a baseline view of the uterus and ovaries. A speculum is inserted, similar to a Pap test, and the cervix is cleansed before a thin catheter is threaded into the uterine cavity. After speculum removal, a transvaginal ultrasound probe is reinserted, and sterile saline is slowly infused through the catheter while real-time images are captured, showing the expanded uterine cavity. Patients may experience mild to moderate menstrual-like cramping, which typically subsides afterward.
Interpreting the Findings
During the saline sonogram, medical professionals examine the uterine cavity for irregularities. Saline distension allows clear identification of abnormalities not visible with standard ultrasound. Endometrial polyps often appear as distinct, bright masses protruding into the cavity. Submucosal fibroids, growing into the uterine cavity, are identified as denser areas distorting the uterine lining.
Intrauterine adhesions (scar tissue) may appear as bands of tissue bridging the uterine cavity. Congenital uterine anomalies, such as a uterine septum (a wall dividing the uterus), are also clearly delineated with saline. Detailed images from a saline sonogram are accurate in detecting these abnormalities, guiding healthcare providers in determining next steps for patient care.