Navigating Ovarian-Adnexal Reporting and Data System Magnetic Resonance Imaging (O-RADS MRI): A Review of Its Evolution, Current Advances, and Persistent Challenges in Ovarian Imaging

Abstract

The Ovarian-Adnexal Reporting and Data System magnetic resonance imaging (O-RADS MRI) is a standardized risk stratification system designed to enhance uniform interpretation and reporting of adnexal masses on MRI. A PubMed search was conducted using the keyword "O-RADS MRI," yielding 61 articles in the search results. After excluding eight articles, 53 articles were selected. Additionally, five articles were identified through a citation search. A total of 58 articles were included in this literature review. Ultrasonography (USG) is the primary imaging modality used for evaluating adnexal lesions, with MRI reserved for cases that require further evaluation. Based on both USG and MRI imaging, various scores are assigned to a particular lesion. Contrast imaging, utilizing both ultrasound USG and MRI, is employed for the better characterization of lesions in terms of internal morphology, with a primary focus on solid components. Additionally, internal septation, wall characteristics, and other soft tissue components, including fat, fibrous tissue, and blood products, are also evaluated. Advanced MRI techniques, such as diffusion-weighted imaging and dynamic contrast-enhanced sequences, also help refine the final O-RADS score of a lesion. Contrast-Enhanced Computed Tomography (CECT) plays a predominant role in evaluating metastatic disease and has been established in five cases. This review article provides a comprehensive overview of O-RADS MRI, addressing its development, key imaging features, and practical application in a clinical setup. We discuss the diagnostic performance of O-RADS MRI in differentiating benign from malignant adnexal lesions, exploring its strengths in reducing inter-observer variability and guiding patient management. We also highlighted various comparative studies and trials that have shaped the evolution of the O-RADS MRI system over time. Furthermore, this article highlights the challenges associated with implementing O-RADS MRI, including potential pitfalls in interpretation, corroborations, and discordance with other imaging modalities, particularly USG, as well as the need for further validation studies.

Keywords: adnexal mass lesion; cect; dwi-adc; mri; o-rads mri; time-signal intensity curve; usg.

Figure 1. PRISMA flowchart summarizes the study selection process.

PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses