Preoperative Staging of Endometriosis: The Value of MRI After Dynamic Transvaginal Ultrasound

Magnetic resonance imaging examination after dynamic transvaginal ultrasound does not have additional value for preoperative staging of pelvic endometriosis.

Key Points

Highlights:

• There is no significant added value of routine magnetic resonance imaging (MRI) after dynamic transvaginal ultrasound (TVUS) for the preoperative staging of endometriosis.

Importance:

• Choosing proper diagnostic imaging will result in the reduction of costs for routine MRI scans and better personalized preoperative counseling will be given to the patient.

Objective:

• To investigate if MRI after dynamic TVUS adds any value to the diagnostic pathway for pre-operative staging of pelvic endometriosis.

What's done here:

• In this prospective observational study, 363 patients with a clinical suspicion of endometriosis, were included.
• Of 363 patients, 72 were selected for surgery and underwent the full diagnostic pathway: ie, history, clinical examination, dynamic TVUS, and MRI.

Key Results:

• Of 72 patients who underwent surgery, 59 showed deep infiltrating endometriosis confirmed by laparoscopy; 13 had a diagnosis of low-grade endometriosis; all had peritoneal endometriosis.
• The sensitivity and specificity for the history, pelvic examination, and dynamic TVUS were 93.7% and 55.6%, respectively; and when the MRI findings were included, the sensitivity and specificity became 85.9% and 62.5%.
• Correct staging after dynamic TVUS was 88.9%; after the addition of MRI, it was 83.3%.  
• Adding MRI routinely to the diagnostic procedure of endometriosis did not significantly improve the sensitivity or specificity.

Limitations:

• The classification by the revised American Fertility Society (AFS) system was used in this study although both the Enzian score and the scoring system used by Coccia and Rizello.
• Since the study was performed in a center with expertise in endometriosis and low-grade endometriosis was treated conservatively, the prevalence of deep infiltrating endometriosis was found to be high, resulting in a particularly high rate of diagnosis by the clinical history and physical examination.

Lay Summary

Since endometriosis is a chronic and progressive disease, early diagnosis and proper staging are important for the patient and for the clinician to discuss and plan the required surgical procedures for treatment. Common diagnostic tools for pre-operative staging of deep infiltrating endometriosis are the clinical history, physical examination, dynamic TVUS, and MRI.

A team of researchers from Netherlands, Berger et al., evaluated the added value of each step (history, clinical examination, dynamic TVUS, and MRI) in the diagnostic pathway for the assessment of (deep infiltrating) endometriosis in outpatient settings. Their study has been published in the Journal of Ultrasound in Medicine.

The participants of the study were 363 patients with a clinical suspicion of endometriosis, during the period between April 22, 2014, and May 1, 2015. Patients younger than age 18 years, patients for whom dynamic TVUS was not possible and patients with claustrophobia or contraindications to MRI were excluded. Of 363 patients, 72 were selected for surgery and underwent the full diagnostic pathway: ie, history, clinical examination, dynamic TVUS, and MRI.

Of 72 patients who underwent surgery, 59 showed deep infiltrating endometriosis which was confirmed by laparoscopy; and 13 patients had a diagnosis of low-grade endometriosis. All patients had peritoneal endometriosis; 34 patients had bowel endometriosis; 3 patients had bladder endometriosis; 3 patients had endometriosis around the ureter, and 26 patients had an ovarian endometrioma.

The sensitivity after adding the results from the history, clinical examination, and dynamic TVUS was 93.7%. When the MRI results were included, the sensitivity was 85.9%. However, after including MRI, the specificity was less for dynamic TVUS only. Correct staging after dynamic TVUS was 88.9%; and after MRI, it was 83.3%. Considering dynamic TVUS findings only, underestimation by 1 stage performed better than after inclusion of MRI findings

According to the authors’ opinions, since dynamic TVUS has the ability to evaluate the mobility of the pelvic organs and site-specific pain, the correct stage of disease was better predicted after the dynamic TVUS compared to that after MRI.

For diagnosis of pelvic endometriosis and deep infiltrating endometriosis, the inclusion of dynamic TVUS alone performed as well as after MRI. Dynamic TVUS performed even better at predicting the correct stage in patients predominantly affected by deep infiltrating endometriosis.

The authors conclude that their study is the first prospective study to evaluate the added value of MRI after dynamic TVUS for staging endometriosis preoperatively and to test its usefulness in routine clinical practice. They demonstrated that after the history and physical examination, dynamic TVUS and MRI both yield similar added value in preoperative staging of endometriosis. Choosing proper diagnostic imaging depends on the availability of an expert sonographer or MRI radiologist and on the anatomic site of interest based on the history and physical examination. They expect this approach to eventually result in the reduction of costs for routine MRI scans and more personalized preoperative counseling to be given to the patient.

Research Source: https://www.ncbi.nlm.nih.gov/pubmed/30244483