Evaluation of known endometriosis with MRI requires a slightly different protocol to a routine pelvic MRI (see Pelvic MRI protocol: routine), and should probably be reserved for known cases of endometriosis rather than for the assessment of pelvic pain.
IV (or IM) Buscopan® is administered to reduce bowel peristalsis and hence improve image quality.
A good protocol involves:
- body coil
- T1W and T2W axial
- T1W fat-suppressed sequences 1: axial, sagittal and coronal
Gadolinium is not particularly useful in the evaluation of endometriomas 2 and does not improve detection of very small implants as small vessels enhance and may be misinterpreted as a small endometriotic deposit 1. Additionally, enhancement of endometrial deposits is variable post contrast and does not differentiate from other benign or malignant processes.
- 1. Sugimura K, Okizuka H, Imaoka I et-al. Pelvic endometriosis: detection and diagnosis with chemical shift MR imaging. Radiology. 1993;188 (2): 435-8. Radiology (abstract) - Pubmed citation
- 2. Ascher SM, Agrawal R, Bis KG et-al. Endometriosis: appearance and detection with conventional and contrast-enhanced fat-suppressed spin-echo techniques. J Magn Reson Imaging. 5 (3): 251-7. - Pubmed citation
- 3. Ha HK, Lim YT, Kim HS et-al. Diagnosis of pelvic endometriosis: fat-suppressed T1-weighted vs conventional MR images. AJR Am J Roentgenol. 1994;163 (1): 127-31. AJR Am J Roentgenol (abstract) - Pubmed citation