Impact of Adding Mean Apparent Diffusion Coefficient (ADCmean) Measurements to O-RADS MRI Scoring For Adnexal Lesions Characterization: A Combined O-RADS MRI/ADCmean Approach

Published:September 07, 2022DOI:

      Rationale and Objectives

      Evaluate the impact of adding mean apparent diffusion coefficient (ADCmean) measurements to the Ovarian-Adnexal Imaging Reporting and Data System MRI (O-RADS MRI) scoring for adnexal lesion characterization using a combined O-RADS MRI/ADCmean reading approach.

      Materials and Methods

      This prospective study included 90 women who underwent pelvic MRI for adnexal lesions diagnosis and characterization. Two readers scored the adnexal lesions using the O-RADS MRI scoring independently and in consensus. A third reader calculated ADCmean measurements. The final diagnoses were determined by histo-pathology (n = 77) or follow-up imaging (n = 13). Areas under the curves (AUCs) and diagnostic performance metrics were calculated for the O-RADS MRI scoring, ADCmean, and combined O-RADS MRI/ADCmean thresholds. P-value <0.05 was significant.


      116 adnexal lesions (71 benign, 45 malignant) were analyzed. The optimal thresholds to predict malignant adnexal lesions were O-RADS MRI score >3 and ADCmean value ≤1.08 × 10−3 mm2/s (AUC 0.926 and 0.823; sensitivity 97.7% and 95.5%; specificity 87.3% and 68%; positive predictive value (PPV) 83% and 66.2%; positive likelihood ratio (PLR) 7.7 and 3.08, respectively). Compared to the O-RADS MRI scoring, a combined threshold of O-RADS MRI >3/ADCmean ≤1.08 × 10−3 mm2/s, yielded a reduction of false positives, a significant increase in the specificity (97.1%, p = 0.005), PPV (95.4%, p = 0.002), and PLR (33.1, p <0.0001), and non-significant change in the AUC (0.953, p = 0.252), and sensitivity (93.3%, p = 0.467).


      The diagnostic performance of O-RADS MRI scoring to characterize adnexal lesions could be improved by adding the ADCmean values through reducing false positives, increasing specificity, and maintaining good sensitivity.

      Key Words


      ACR (American College of Radiology), ADCmean (mean apparent diffusion coefficient.), AUC (area under the curve), CE (contrast-enhanced), DWI (diffusion-weighted imaging), ICC (intra-class correlation), k (kappa score), MRI (Magnetic resonance imaging), O-RADS (Ovarian-Adnexal Imaging-Reporting and Data System), ROC (receiver operating characteristic), ROI (region of interest), SI (Signal intensity), T2W (T2-weighted), T1W (T1-weighted), US (ultrasound)
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Academic Radiology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Sohaib SA
        • Sahdev A
        • Trappen PV
        • et al.
        Characterization of adnexal mass lesions on MR imaging.
        Am J Roentgenol. 2003; 180: 1297-1304
        • Jeong YY
        • Outwater EK
        • Kang HK.
        Imaging evaluation of ovarian masses.
        Radiographics. 2000; 20: 1445-1470
        • Ratner ES
        • Staib LH
        • Cross SN
        • et al.
        The clinical impact of gynecologic MRI.
        Am J Roentgenol. 2015; 204: 674-680
        • Thomassin-Naggara I
        • Aubert E
        • Rockall A
        • et al.
        Adnexal masses: development and preliminary validation of an MRI scoring system.
        Radiology. 2013; 267: 432-443
        • Thomassin-Naggara I
        • Poncelet E
        • Jalaguier-Coudray A
        • et al.
        Ovarian-adnexal reporting data system magnetic resonance imaging (O-RADS MRI) score for risk stratification of sonographically indeterminate adnexal masses.
        JAMA Netw Open. 2020; 3e1919896
      1. American College of Radiology (ACR). Ovarian-Adnexal Reporting and Data System (O–RADS). American College of Radiology (ACR) Web site. Available at: Accessed April 6, 2022.

        • Hricak H
        • Chen M
        • Coakley FV
        • et al.
        Complex adnexal masses: detection and characterization with MR imaging-multivariate analysis.
        Radiology. 2000; 214: 39-46
        • Thomassin-Naggara I
        • Daraï E
        • Cuenod CA
        • et al.
        Dynamic contrast-enhanced magnetic resonance imaging: a useful tool for characterizing ovarian epithelial tumors.
        J Magn Reson Imaging. 2008; 28: 111-120
        • Thomassin-Naggara I
        • Daraï E
        • Cuenod CA
        • et al.
        Contribution of diffusion-weighted MR imaging for predicting benignity of complex adnexal masses.
        Eur Radiol. 2009; 19: 1544-1552
        • Hu X
        • Liang Z
        • Zhang C
        • et al.
        The diagnostic performance of maximum uptake value and apparent diffusion coefficient in differentiating benign and malignant ovarian or adnexal masses: a meta-analysis.
        Front Oncol. 2022; 12840433
        • Zhang H
        • Zhang GF
        • He ZY
        • et al.
        Evaluation of primary adnexal masses by 3T MRI: categorization with conventional MR imaging and diffusion-weighted imaging.
        J Ovarian Res. 2012; 5: 1-8
        • Kim HJ
        • Lee SY
        • Shin YR
        • et al.
        The value of diffusion-weighted imaging in the differential diagnosis of ovarian lesions: a meta-analysis.
        PloS one. 2016; 11e0149465
        • Agostinho L
        • Horta M
        • Salvador JC
        • et al.
        Benign ovarian lesions with restricted diffusion.
        Radiologia Brasileira. 2019; 52: 106-111
        • Takeuchi M
        • Matsuzaki K
        • Nishitani H.
        Diffusion-weighted magnetic resonance imaging of ovarian tumors: differentiation of benign and malignant solid components of ovarian masses.
        J Comput Assist Tomog. 2010; 34: 173-176
        • Malek M
        • Pourashraf M
        • Mousavi AS
        • et al.
        Differentiation of benign from malignant adnexal masses by functional 3 tesla MRI techniques: diffusion-weighted imaging and time-intensity curves of dynamic contrast-enhanced MRI.
        Asian Pac J Cancer Prev. 2015; 16: 3407-3412
        • Aslan S
        • Tosun SA.
        Diagnostic accuracy and validity of the O-RADS MRI score based on a simplified MRI protocol: a single tertiary center retrospective study.
        Acta Radiologica. 2021; 02841851211060413
        • Hottat NA
        • Badr DA
        • Van Pachterbeke C
        • et al.
        Added value of quantitative analysis of diffusion-weighted imaging in ovarian-adnexal reporting and data system magnetic resonance imaging.
        J Magn Reson Imaging. 2021; 56: 158-170
        • Assouline V
        • Dabi Y
        • Jalaguier-Coudray A
        • et al.
        How to improve O-RADS MRI score for rating adnexal masses with cystic component?.
        Eur Radiol. 2022; 24: 1-11
        • Sadowski EA
        • Robbins JB
        • Rockall AG
        • et al.
        A systematic approach to adnexal masses discovered on ultrasound: the ADNEx MR scoring system.
        Abdom Radiol. 2018; 43: 679-695
        • Lin Y
        • Hsieh CY
        • Huang YL
        • et al.
        Magnetic resonance spectroscopy for risk stratification of sonographically indeterminate ovarian neoplasms: preliminary study.
        Diagnostics. 2021; 11: 1847
        • Reinhold C
        • Rockall A
        • Sadowski EA
        • et al.
        Ovarian-adnexal reporting lexicon for MRI: a white paper of the ACR ovarian-adnexal reporting and data systems MRI committee.
        J Am Coll Radiol. 2021; 18: 713-729
        • Patel MD
        • Ascher SM
        • Horrow MM
        • et al.
        Management of incidental adnexal findings on CT and MRI: a white paper of the ACR incidental findings committee.
        J Am Coll Radiol. 2020; 17: 248-254
        • Hauptmann S
        • Friedrich K
        • Redline R
        • et al.
        Ovarian borderline tumors in the 2014 WHO classification: evolving concepts and diagnostic criteria.
        Virchows Arch. 2017; 470: 125-142
        • Ozturk M
        • Polat AV
        • Selcuk MB.
        Whole-lesion ADC histogram analysis versus single-slice ADC measurement for the differentiation of benign and malignant soft tissue tumors.
        Eur J Radiol. 2021; 143109934
        • Levy A
        • Medjhoul A
        • Caramella C
        • et al.
        Interest of diffusion-weighted echo-planar MR imaging and apparent diffusion coefficient mapping in gynecological malignancies: a review.
        J Magn Reson Imaging. 2011; 33: 1020-1027