Lay Summary: MRI should be reserved for problem solving when CT is not conclusive.
RI is an excellent problem-solving technique by virtue of its ability to define common conditions such as fibroids, dermoid cysts, endometriomas, and other benign lesions. Two studies found no statistical difference between CT and MRI in defining disease extent. A multivariate analysis showed that the accuracy of MRI with gadolinium enhancement in diagnosing ovarian malignancy was 93%. Gadolinium enhancement improved diagnostic confidence and tissue characterization. However, the role of MRI has been limited because the use of intraluminal gastrointestinal contrast agents with MRI is not routine as it is with CT, MRI generally costs more than CT, and there are fewer experienced radiologists to interpret MRI. Thus, CT is currently the recommended modality to stage ovarian cancer. MRI is recommended for patients with a contraindication to the use of iodinated contrast agents (allergy, renal insufficiency), patients who are pregnant, and those for whom CT findings are inconclusive.
A recent guideline rates MRI as 8 : “Evidence shows equivalent staging accuracy compared to CT. Problem solving modality for patients who cannot have contrast enhanced CT. ”
Javitt MC, Fleischer AC, Andreotti RF, Angtuaco TL, Horrow MM, Lee SI, Lev-Toaff AS, Scoutt LM, Zelop C, Expert Panel on Women’s Imaging. Staging and follow-up of ovarian cancer. [online publication]. Reston (VA): American College of Radiology (ACR); 2007. 5 p. [38 references]
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