Can endometriosis be visualized on transvaginal (trans vaginal) ultrasound?

From the Guidelines

Transvaginal ultrasound is a useful diagnostic tool for detecting endometriosis, particularly for identifying ovarian endometriomas and deep infiltrating endometriosis, as evidenced by a 2024 study published in the Journal of the American College of Radiology 1. When evaluating endometriosis using transvaginal ultrasound, it is essential to consider the type and location of the lesions. The ultrasound is most reliable for detecting endometriomas and deep infiltrating endometriosis, especially when it affects the bladder, rectum, or rectovaginal septum. However, it often cannot visualize superficial peritoneal endometriosis lesions, which are common forms of the disease.

• The accuracy of transvaginal ultrasound for detecting endometriosis can vary depending on the operator's skill and the use of expanded protocols that include evaluation of additional anatomic landmarks and scanning maneuvers 1.
• A study found that "community US" was less beneficial for detection of endometriosis, highlighting the importance of specialized ultrasound performed by clinicians with expertise in endometriosis imaging 1.
• The uterine sliding sign has been shown to have good diagnostic performance for detection of endometriosis involving the bowel and pouch of Douglas, and some authors advocate including this with a routine pelvic US to help diagnose endometriosis 1.
• While a positive finding on ultrasound can confirm endometriosis, a normal ultrasound cannot rule it out, and laparoscopy remains the gold standard for definitive diagnosis of endometriosis.
• If endometriosis is suspected despite negative ultrasound findings, referral to a gynecologist for further evaluation is recommended, especially if the patient has symptoms like severe menstrual pain, pain during intercourse, or infertility.

From the Research

Endometriosis Diagnosis using Transvaginal Ultrasound

• Endometriosis can be diagnosed using transvaginal ultrasound (TVS), which is a common imaging modality for this condition 2, 3, 4, 5, 6.
• TVS can adequately assess ovarian endometriomas (OMAs) and deep infiltrating endometriosis (DIE), but may have limitations in diagnosing superficial peritoneal endometriosis (SUP) 2.
• The sensitivity and specificity of TVUS in detecting DIE are comparable to those of MRI, making it a valuable tool in preoperative planning 5.
• TVUS can be used to non-invasively stage endometriosis using available classification systems, such as rASRM and ENZIAN 2.
• The accuracy of TVUS in diagnosing endometriosis may be affected by factors such as age and body mass index (BMI), with higher accuracy observed in women with a normal BMI and under 35 years old 6.

Types of Endometriosis Diagnosable by TVS

• Ovarian endometriomas (OMAs) can be adequately assessed by TVS 2.
• Deep infiltrating endometriosis (DIE) can be diagnosed by TVUS with sensitivity and specificity comparable to MRI 5.
• Superficial peritoneal endometriosis (SUP) is challenging to diagnose by TVS or MRI 2.

Advantages and Limitations of TVS in Endometriosis Diagnosis

• TVS has satisfactory overall diagnostic accuracy, wide availability, and low cost, making it a suitable first-line imaging modality for endometriosis diagnosis 2.
• TVUS can eliminate the need for MRI in most patients and reduce the need for diagnostic laparoscopy, proving to be an important tool in preoperative planning 5.
• However, the accuracy of TVUS may be limited by factors such as age, BMI, and the presence of superficial peritoneal endometriosis 2, 6.