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PubMed This is a summary of 21 peer-reviewed journal articles Updated
Gynecology

Diagnosis, Imaging, and Scoring Systems

At a Glance

Modern guidelines state that endometriosis can often be diagnosed with specialized ultrasounds or MRIs, avoiding initial surgery. Imaging looks for the "sliding sign" and uses the #Enzian system to map deep lesions, helping specialists plan treatment and assess fertility options.

For decades, the only way to get a definitive diagnosis of endometriosis was through a surgical procedure called a laparoscopy. However, a major shift in medical guidelines has changed this. Modern imaging and scoring systems now allow doctors to create a detailed “roadmap” of your disease, often without the need for initial surgery.

The Imaging Revolution

The 2022 ESHRE guidelines officially recognize that a diagnosis can now be made using clinical history and high-quality imaging, such as specialized transvaginal ultrasound (TVUS) or pelvic MRI [1][2]. These tools are highly accurate at identifying deep infiltrating disease and ovarian cysts [3][4].

One of the most important parts of a specialized ultrasound is the “sliding sign” [5][6]. During the scan, the technician uses the probe to see if your pelvic organs—like your uterus and bowel—slide freely against each other. If they don’t, it is a strong indicator of adhesions (scar tissue) and potential Pouch of Douglas (POD) obliteration, where the space behind the uterus is “closed up” by the disease [7][6].

#Enzian: Mapping Your Disease

If your imaging shows signs of Deep Infiltrating Endometriosis (DIE), your doctor may use the #Enzian classification system [8][9]. Think of this as a GPS for your endometriosis; it maps exactly where the disease is located and how large the lesions are [10].

The #Enzian system looks at three primary “compartments”:

  • Compartment A: The vagina and the rectovaginal space [10].
  • Compartment B: The uterosacral ligaments (the “anchors” for your uterus) and the pelvic sidewall [11][12].
  • Compartment C: The rectum and sigmoid colon [11][13].

By using this standardized language, your medical team can precisely plan for surgery or monitor how the disease is responding to treatment over time [14][15].

EFI: Predicting Your Fertility (and Pre-Surgery Decisions)

If you are planning to conceive, the timing of surgery is a critical conversation to have before you enter the operating room. Surgery on the ovaries to remove endometriomas can significantly lower your Anti-Müllerian Hormone (AMH), reducing your egg reserve. It is strongly advised to consult with a Reproductive Endocrinologist (RE) before surgery to discuss freezing your eggs, balancing the need for pain relief against protecting your natural conception chances.

After surgery, your doctor can calculate your Endometriosis Fertility Index (EFI) [16][17]. This is a validated scoring system used to predict your chances of spontaneous (natural) pregnancy post-operatively [16][18].

The EFI score is based on:

  1. Historical Factors: Your age, how long you’ve been trying to conceive, and your pregnancy history [19].
  2. Surgical Findings: A “least function” score that assesses how well your fallopian tubes and ovaries are working after the endometriosis has been removed [19][18].

A score of 5 or higher suggests a good chance of natural conception, while a score of 4 or lower may lead your doctor to recommend moving toward Assisted Reproductive Technology (ART), such as IVF, sooner [20][21].

Checklist: What to Look for in Your Report

When you receive your imaging or pathology report, look for these specific details. If they are missing, you may want to ask for a review by an endometriosis specialist:

  • The Sliding Sign: Is it recorded as “positive” (organs slide) or “negative” (organs are fixed)? [5]
  • Ovarian Mobility: Are your ovaries “mobile” or are they “fixed” to the pelvic wall or uterus? [7]
  • Nodule Measurements: If deep lesions were found, are their length and thickness (depth of invasion) listed in millimeters? [14]
  • Pouch of Douglas (POD): Is it described as “clear,” “partially obliterated,” or “completely obliterated”? [7]
  • Organ Specifics: Are there specific mentions of the bowel, bladder, or uterosacral ligaments? [10]
  • Classification Codes: Does the report mention an #Enzian score or an rASRM stage? [8]

Common questions in this guide

Do I need surgery to be diagnosed with endometriosis?
No, recent medical guidelines state that a diagnosis can often be made using your clinical history and high-quality imaging, such as a specialized transvaginal ultrasound or pelvic MRI, without needing a diagnostic laparoscopy first.
What is the sliding sign on an endometriosis ultrasound?
The sliding sign is checked during a specialized ultrasound to see if your pelvic organs move freely against each other. If they do not slide, it strongly indicates the presence of scar tissue and adhesions from endometriosis.
What does the #Enzian classification mean on my report?
The #Enzian system is a medical mapping tool for your disease. Doctors use it to record the exact location and size of deep infiltrating endometriosis lesions across different areas of your pelvis, which helps them accurately plan your surgery.
Should I freeze my eggs before endometriosis surgery?
Surgery to remove ovarian endometriomas can lower your egg reserve. It is highly recommended to consult a reproductive endocrinologist before surgery to discuss egg freezing, balancing your need for pain relief with your future family goals.
What is the Endometriosis Fertility Index (EFI)?
The EFI is a scoring system calculated after endometriosis surgery to predict your chances of getting pregnant naturally. A higher score suggests a good chance of natural conception, while a lower score may indicate you should consider treatments like IVF sooner.

Questions to Ask Your Doctor

Curated prompts to bring to your next appointment.

  1. 1.Was the ultrasound I received a 'specialized' scan that included checking for the 'sliding sign' and ovarian mobility?
  2. 2.Does my imaging report use the #Enzian classification to map the location and size of any deep infiltrating lesions?
  3. 3.Based on my #Enzian mapping, are my bowel (Compartment C) or uterosacral ligaments (Compartment B) involved?
  4. 4.Given my endometriomas, should I consult a reproductive endocrinologist to discuss freezing eggs before we proceed with surgery?
  5. 5.Given the 2022 ESHRE guidelines, can we proceed with a treatment plan based on my current imaging results instead of doing a diagnostic laparoscopy?

Questions For You

Tap a prompt to share your answer — we'll use it plus this page's context to start a tailored conversation.

References

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This page explains endometriosis imaging and scoring systems for educational purposes only. Always consult your gynecologist or an endometriosis specialist to interpret your specific scan results and develop a personalized treatment plan.

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