Suspected endometriosis, including deep disease
ESUR MRI endometriosis consensus (2025); ESHRE 2022Detection and mapping of endometriosis. Specialist transvaginal ultrasound is the first-line test; MRI answers the negative or inconclusive scan in a symptomatic woman and maps disease before surgery, and it must be protocolled for endometriosis rather than as a general pelvic MRI.
Cyclical pelvic pain, dysmenorrhoea, dyspareunia, subfertility, or cyclical bowel or urinary symptoms, often after years of non-specific investigation.
Referenced decision support — confirm against your local protocol.
Decision support, not a directive. Protocols and timings shown are typical published ones — your local protocol takes precedence, and the vetting radiologist decides.
Accept as requested
Pelvic ultrasound — transabdominal and transvaginal
Ultrasound pelvis (transabdominal ± transvaginal)
What we'd amend, and why
- Transvaginal ultrasound performed by an operator trained in endometriosis is the accepted first-line test: it detects endometriomas reliably and, with dynamic manoeuvres, assesses ovarian mobility, site-specific tenderness and pouch of Douglas obliteration — real-time information that no static cross-sectional study can produce.
Nothing needs resolving before this goes ahead. Routine checks below are owned downstream.
How was this decided?
- pathwayany — All patients
Decision support only. Local protocol takes precedence.
Pathways
Big forks are separate pathways; the first whose conditions match is the one used.
All patients
Matches your inputsDefault| Role | Study & protocol | Why this answers the question |
|---|---|---|
| First line | Ultrasound pelvis (transabdominal ± transvaginal) Pelvic ultrasound — transabdominal and transvaginal | Transvaginal ultrasound performed by an operator trained in endometriosis is the accepted first-line test: it detects endometriomas reliably and, with dynamic manoeuvres, assesses ovarian mobility, site-specific tenderness and pouch of Douglas obliteration — real-time information that no static cross-sectional study can produce. |
| Second line | MRI Pelvis (Gynaecological) MRI Pelvis — deep endometriosis | MRI is indicated when ultrasound is negative or inconclusive in a symptomatic woman, and before excisional surgery. High-resolution T2 imaging shows the fibrotic nodules and tethering that define deep disease, fat-suppressed T1 identifies haemorrhagic implants that T2 alone hides, and extending the coverage to the kidneys detects the silent hydronephrosis of ureteric involvement. Intravenous contrast is not part of the consensus protocol for this question. |
- Bowel preparation, an antiperistaltic agent and a few hours of fasting materially change image quality for deep disease; they are worth building into the booking rather than discovering on the day.
- Bladder filling is part of the protocol, not a comfort question: the ESUR consensus asks for a moderately full bladder, because an empty bladder collapses the anterior compartment and hides vesicouterine and bladder-wall disease, while an overfull one displaces the uterus and makes a long acquisition intolerable. Ask the patient to void about an hour before and not again.
Pitfalls
- Booking a general pelvic MRI. Without the high-resolution multiplanar T2 and fat-suppressed T1 sequences, deep endometriosis is routinely missed, and the study then has to be repeated.
- Reporting "no endometriosis" after a negative study; the accurate statement is that no deep or ovarian disease is demonstrated, since superficial peritoneal implants are beyond the resolution of any imaging.
- Omitting the renal tract from the coverage and missing obstructive uropathy from a ureteric nodule.
- Scanning through an empty bladder. The anterior compartment collapses, and bladder-wall and vesicouterine disease — the finding that puts a urologist in theatre — is the disease most often missed on an otherwise adequate study.
- Treating an endometrioma as the whole diagnosis — the pelvic side-wall, uterosacral and bowel disease that determines the operation is what the request is really asking about.
Priors — what to pull first
- Previous operation notes and laparoscopy findings define what is recurrent and what is new, and are more useful than any prior report.
- Check for previous imaging showing an ovarian cyst called haemorrhagic — a recurring "haemorrhagic cyst" at the same site is usually an endometrioma.
What makes a good request
- A negative ultrasound in a symptomatic woman does not exclude endometriosis; superficial peritoneal disease is invisible to both ultrasound and MRI.
- If the question is surgical planning, say so: the operation booked depends on whether bowel, ureter or bladder is involved, and that determines which specialties need to be in theatre.
- The imaging report should follow a compartmental structure — anterior, middle and posterior — because that is how the surgical team thinks about the pelvis.
How these studies are acquired
Contrast, phases and timing for every study on the pathways above.
Confirm locally
- Timings, contrast volumes and rates above are typical published values. Your department's protocol, scanner and patient population decide the actual numbers.
- Safety thresholds and premedication policy follow local policy where it differs from the cited guidance.
References
- ESUR consensus MRI for endometriosis: protocol, lexicon and compartment-based analysis (Eur Radiol 2025) · ESUR
- ESHRE guideline: endometriosis (2022) · Other
- International Consensus Statement on non-invasive imaging for pelvic deep endometriosis and classification systems · Primary literature
Implemented from the cited published sources. Educational and workflow support only; confirm against current guidelines and local policy before clinical use.