MRI Pelvis — deep endometriosis
Pelvis from above the uterine fundus to the perineum, with sequences extended to include both kidneys to detect ureteric obstruction.
Typical, not policy
Timings, volumes and delays here are representative values drawn from published guidance. Scanner generation, injector, cardiac output and local preference all move them. Confirm against your department's own protocol before you rely on a number.
When to use it
- Chronic pelvic pain, dysmenorrhoea, dyspareunia or cyclical bowel or urinary symptoms with suspected deep endometriosis.
- Pre-operative mapping before excisional surgery, where bowel, ureteric and bladder involvement changes the surgical team required.
- Suspected ureteric or bowel endometriosis with obstructive features.
- Characterisation of an adnexal cyst suspected to be an endometrioma.
- Assessment of recurrent symptoms after previous endometriosis surgery.
Technique
- Multiplanar high-resolution T2 without fat suppression, covering the anterior, middle and posterior compartments as defined in the consensus compartmental scheme.
- Axial T1 with and without fat suppression: fat-suppressed T1 high signal foci are what identify superficial and deep haemorrhagic implants.
- Sequences extended to include the kidneys for hydronephrosis.
- Preparation matters: fasting, an antiperistaltic agent, moderate bladder filling and, in some protocols, bowel preparation or vaginal and rectal gel. Practice varies considerably.
Where it goes wrong
- Fat-suppressed T1 omitted, which is the single sequence that identifies small haemorrhagic implants.
- Bladder empty, so bladder-dome and vesicouterine-pouch disease is not assessable.
- Renal coverage omitted, missing silent hydronephrosis from ureteric involvement.
- Bowel motion obscuring the rectosigmoid, which is the commonest site of deep disease.
- Scheduling without regard to bowel and bladder preparation, producing a study that cannot answer the surgical question.
Clinical questions that reach this study
Suspected ectopic pregnancyAcute pelvic pain in the reproductive age group (including suspected PID and tubo-ovarian abscess)Suspected ovarian (adnexal) torsionAdnexal mass — characterisation and risk stratificationSuspected endometriosis, including deep diseaseAbnormal uterine bleeding and endometrial assessmentSuspected ovarian cancer or indeterminate adnexal massEndometrial cancer — stagingCervical cancer — staging
Contrast
None
- Intravenous contrast is not required for endometriosis mapping and is not part of the consensus protocol.
Acquisition
- Breathing
- Free breathing with an antiperistaltic agent; fasting for a few hours reduces bowel motion.
- Preparation
- Moderate bladder filling is wanted for most gynaecological protocols; an over-full bladder causes motion and an empty one loses anatomical separation. Fasting for a few hours plus an antiperistaltic agent reduces bowel motion for high-resolution sequences. Intrauterine devices are MR-conditional in general but must still be declared at screening.
Safety checks this protocol carries
Derived from the contrast agent and phases above, not authored here — which is why they cannot drift apart from what the protocol actually does.
- Kidney function and gadolinium-based contrast· radiographer at scan
- MR safety screening for implants and foreign bodies· radiographer at scan
- Gadolinium in known or possible pregnancy· radiographer at scan