Search

Background: MRI is the best imaging tool for the evaluation of uterine tumors, but conventional MRI diagnosis results rely on radiologists and contrast agents (if needed). As a new objective, reproducible and contrast-agent free quantification technique, T2 mapping has been applied to a number of diseases, but studies on the evaluation of uterine lesions and the influence of magnetic field strength are few. Therefore, the aim of this study was to systematically investigate and compare the performance of T2 mapping as a nonenhanced imaging tool in discriminating common uterine lesions between 1.5 T and 3.0 T MRI systems., Methods: A total of 50 healthy subjects and 126 patients with suspected uterine lesions were enrolled in our study, and routine uterine MRI sequences with additional T2 mapping sequences were performed. T2 maps were calculated by monoexponential fitting using a custom code in MATLAB. T2 values of normal uterine structures in the healthy group and lesions (benign: adenomyosis, myoma, endometrial polyps; malignant: cervical cancer, endometrial carcinoma) in the patient group were collected. The differences in T2 values between 1.5 T MRI and 3.0 T MRI in any normal structure or lesion were compared. The comparison of T2 values between benign and malignant lesions was also performed under each magnetic field strength, and the diagnostic efficacies of the T2 value obtained through receiver operating characteristic (ROC) analysis were compared between 1.5 T and 3.0 T., Results: The mean T2 value of any normal uterine structure or uterine lesion under 3.0 T MRI was significantly lower than that under 1.5 T MRI (p < 0.05). There were significant differences in T2 values between each lesion subgroup under both 1.5 T and 3.0 T MRI. Moreover, the T2 values of benign lesions (71.1 ± 22.0 ms at 1.5 T and 63.4 ± 19.1 ms at 3.0 T) were also significantly lower than those of malignant lesions (101.1 ± 4.5 ms at 1.5 T and 93.5 ± 5.1 ms at 3.0 T) under both field strengths. In the aspect of differentiating benign from malignant lesions, the area under the curve of the T2 value under 3.0 T (0.94) was significantly higher than that under 1.5 T MRI (0.90) (p = 0.02)., Conclusion: T2 mapping can be a potential tool for quantifying common uterine lesions, and it has better performance in distinguishing benign from malignant lesions under 3.0 T MRI., (© 2023. The Author(s).)

Purposes: Predictive factors of lymph node metastasis (LNM) in pancreatic neuroendocrine tumors (pNETs) are not well established. We sought to identify the value of MR imaging features in preoperatively predicting the lymph node metastasis of pNETs., Materials and Methods: In this study, we enrolled 108 consecutive patients with pNETs between January 2009 and June 2018. MR morphologic features and quantitative data were evaluated. Predictors of LNM were evaluated using univariate and multivariate logistic regression models., Results: A total of 108 patients with pNETs were finally enrolled, including 82 LNM-negative and 26 LNM-positive patients. Features significantly related to the LNM of pNETs at univariate analysis were tumor size > 2 cm (P = 0.003), Ki-67 > 5% (P = 0.002), non-enhancement pattern (P < 0.001), apparent diffusion coefficient value (P < 0.001), main pancreatic duct dilation (P < 0.001) and pancreatic atrophy (P = 0.032) and extrapancreatic tumor spread (P = 0.001), CNRs during arterial, portal and delay phase (P = 0.005, 0.047, and 0.045, respectively), and histological classification (P = 0.006). At multivariate analysis, non-enhancement pattern (P = 0.019; odds ratio, 6.652; 95% CI 1.369, 32.321) and main pancreatic duct dilation (P = 0.018; odds ratio, 6.745; 95% CI 1.379, 32.991) were independent risk factors for predicting the LNM of pNETs., Conclusion: The non-enhancement characteristic and main pancreatic duct dilation appear to be linked with LNM in pNETs. These radiological predictors can be easily obtained preoperatively, and may help to avoid missing pNETs with a high risk of LNM.

Purpose: The purpose of the study was to retrospectively analyze MRI findings of renal cell carcinoma associated with Xp11.2 translocation/TFE3 gene fusion (Xp11.2/TFE RCC) in adults., Methods: Sixteen patients with Xp11.2/TFE RCC were reviewed retrospectively. The clinical characteristics and imaging features were assessed and then compared between metastatic and non-metastatic subgroups., Results: The mean age at diagnosis was 47.4 (20-76) years. Seven (44 %) patients were men, and nine (56 %) patients were women. The lesions predominantly exhibited an endophytic distribution (n = 14, 88 %) with a capsule (n = 16, 100 %), accompanied by solid and cystic patterns (n = 12, 75%) and hemorrhage (n = 11, 69 %). The tumors prevalently appeared hyper- to isointense on T1WI (n = 14, 88 %), hypointense on T2WI (n = 13, 81 %), and hyperintense on DWI (n = 16, 100 %) with a lower ADC (P < 0.001) than that of the surrounding tissue. The tumors were less enhanced than the normal renal cortex in all phases with a prolonged enhancement pattern (P ≤ 0.001). In addition, six patients (38 %) developed recurrence or metastases. The RCCs with metastases showed an irregular shape (P = 0.013), an incomplete capsule (P = 0.018), heterogeneous solid-cystic patterns (P = 0.034), and hemorrhage (P = 0.037) than non-metastatic subgroups., Conclusions: MRI provides valuable information for the diagnosis of adult Xp11.2/TFE RCCs. Features including irregular shape, incomplete capsule, mixed solid-cystic pattern, and hemorrhage may indicate the occurrence of recurrence or metastases.

This study aims to compare contrast enhanced ultrasound (CEUS) and contrast enhanced magnetic resonance imaging (CEMRI) for the detection and characterization of hepatic hemangiomas. Included in this retrospective study were 83 histopathologically confirmed lesions of hemangioma in 66 hospitalized patients who underwent both CEUS and CEMRI and received surgery. The enhancement patterns on CEUS and CEMRI in each lesion were compared and analyzed. In addition, data obtained by the two modalities were then compared with the pathological findings to determine their value in differential diagnosis of hepatic hemangiomas. CEUS diagnosed 78 lesions of hemangioma against 80 by CEMRI. There were no statistical significant differences in the diagnostic value between CEUS and CEMRI in terms of sensitivity (88.0% vs. 92.8%), specificity (99.0% vs. 99.4%), accuracy (97.3% vs. 98.4%), positive predictive value (93.6% vs. 96.3%), and negative predictive value (98.0% vs. 98.8%) (p > 0.05, all). In the arterial phase, the main enhancement pattern on both CEUS and CEMRI was peripheral nodular enhancement (73 vs. 76), but lesions with diffuse enhancement on CEUS outnumbered those on CEMRI (3 vs. 1) and lesions with circular enhancement on CEMRI outnumbered those on CEUS (3 vs. 2). In the portal venous phase and delayed phase, the main enhancement pattern was hyperechoic change on CEUS and hyperintense on CEMRI (66 vs. 65), some lesions presented isoechoic change (12 vs. 15). These results suggested CEUS, an equivalent to CEMRI, may have an added diagnostic value in hemangiomas.

Objective: To analyze the CT and MRI findings and pathological characteristics of retroperitoneal localized Castleman's disease and discuss the diagnostic and differential value of CT and MRI., Methods: CT, MRI and clinical data of retroperitoneal localized Castleman's disease, proved by surgery and pathology, of 13 patients were reviewed. Among them, all the 13 cases received CT, and 4 cases received MRI examination., Results: Among the 13 cases, 12 cases were of hyaline vascular type, and one was of mixed type. All foci were single mass and most foci located in the periphery of the kidney. The maximum diameter was 4.2 cm to 8.6 cm and the mean diameter of all tumors was 5.9 cm. The outline of most tumors was clear and kidney-shaped. On unenhanced CT, 10 cases showed low density and 3 cases showed isodensity. On plain MRI, four cases showed iso-signal on T1WI, three cases showed slightly high signal on T2WI and one showed moderately high signal. The CT and MRI findings were similar on contrast enhanced scan. In arterial phase, 10 cases showed moderate enhancement, 2 cases showed significant enhancement and one case showed moderate enhancement. Five cases showed rather homogeneous enhancement and 8 cases showed heterogeneous enhancement.In venous phase, all the 13 tumors showed continuous enhancement. Eight cases showing heterogeneous enhancement in arterial phase showed expanded range, and among them two cases showed tending to be homogeneous enhancement. Six cases showed areas of low density without enhancement, and 9 cases were accompanied with single or multi-satellite punctuate or striped foci around the tumors., Conclusion: Dynamic contrast-enhanced CT and MRI combined with MR T2WI fat-suppression are of great importance in the diagnosis and identification of retroperitoneal localized Castleman's disease.

Objective: The objective was to retrospectively study computed tomography (CT) and magnetic resonance imaging (MRI) findings of adenosquamous carcinoma of the pancreas (PASC)., Materials and Methods: Twelve patients (six women and six men; mean age, 61.3 years; range, 47-78 years) who presented with PASC as documented by pathologic examination underwent CT (n=10) or both CT and MRI (n=2) examination. Two radiologists evaluated the images and determined the location, size, margin, internal attenuation or signal intensity, contrast enhancement, and pattern for each tumor. Additionally, the presence of poorly enhanced areas, upstream main pancreatic duct (MPD) dilatation, pancreatic atrophy, and peripancreatic tissue metastasis were evaluated. Images were cross-referenced to surgical and pathologic findings., Results: Masses were distributed throughout the pancreas (head, n=6; body, n=1; and tail, n=5). The tumor size ranged from 2.4 to 5.5 cm with an average size of 3.7 cm. Eight (66.7%) masses were ill defined, and seven (58.3%) were partially exophytic. Twelve (100%) masses showed heterogeneous and poorly enhanced areas. The lesions showed weak (n=5), moderate (n=5), or intense (n=2) progressive enhancement. The diameter of MPD in six patients ranged from 3.0 to 5.0 mm with an average of 3.7 mm. Pancreatic atrophy was not found. In 10 patients (83.3%), masses invaded the peripancreatic tissues. Two patients had metastatic liver disease at presentation., Conclusion: PASC typically presented as an ill-defined, hypovascular mass with a poorly enhanced area, exophytic tendency, and peripancreatic tissue invasion. Lack of pancreatic atrophy and mild MPD dilatation were also distinct from common duct pancreatic adenocarcinoma., (© 2013 Elsevier Inc. All rights reserved.)

Objectives: To investigate the feasibility of one-stop examination of aortic pulse wave velocity (PWV) , aortic distensibility (AD), and brachial artery flow-mediated dilation (FMD) in healthy volunteers by means of 3.0-T high-resolution magnetic resonance imaging (MRI)., Methods: A total of 32 healthy volunteers (24-37 years old; mean age, 29 years) underwent repeated high-resolution MRI to assess aortic PWV, ascending aorta (AA) AD, proximal descending aorta (PDA) AD, distal descending aorta (DDA) AD, and FMD of the brachial artery with an interval of 1 to 2 hours. Pulse wave velocity was evaluated by 2-dimensional (2D) phase contrast velocity-encoded MRI with a 4.7- to 7.8-millisecond (ms) temporal resolution. Fiesta-cine MRI was used to assess AD and FMD with a 18.75- to 31.25-ms temporal resolution. The image quality of repeated scans was evaluated with 4-point scores, and the agreement between the 2 scans was tested with kappa analysis. The reproducibility of the results from repeated measurements for PWV, AA-AD, PDA-AD, DDA-AD, and FMD was assessed with intraclass correlation coefficient (ICC) analysis. The method of Bland-Altman plot was also used to assess the agreement between repeated measurements., Results: Each examination including PWV, AD, and FMD were completed in approximately half an hour. The image quality between repeated scans showed good agreement (κ value, 0.776) with a mean score of 3.53 and 3.41, respectively. Reproducibility between repeated measurements was high for aortic PWV (4.33 ± 0.88 vs 4.36 ± 0.88 m/s; ICCPWV = 0.95; P < 0.01), AA-AD (8.60 ± 3.11 vs 8.59 ± 3.10 × 10⁻³ mm Hg⁻¹; ICCAA-AD = 0.97; P < 0.01), PDA-AD (6.95 ± 2.44 vs 6.95 ± 2.42 × 10⁻³ mm Hg⁻¹; ICCPDA-AD = 0.99; P < 0.01), DDA (10.54 ± 2.91 vs 10.55 ± 2.90 × 10⁻³ mm Hg⁻¹; ICCDDA-AD = 0.98, P < 0.01), and FMD (24.94 ± 12.55 vs 24.92 ± 12.38%; ICCFMD = 0.94, P < 0.01). Good agreement between repeated measurements was found for aortic PWV (confidence interval [CI], -0.55 to 0.50), AA-AD (CI, -0.11 to 0.12), PDA-AD (CI, -0.08 to 0.08), DDA-AD (CI, -0.23 to 0.21), and FMD (CI, -1.46 to 1.51)., Conclusion: Comprehensive assessment of aortic compliance and brachial endothelial function can be achieved in a single examination using 3.0-T high-resolution MRI with good reproducibility and within a reasonable amount of time.

Background: Vesical Imaging‐Reporting and Data System (VI‐RADS) has been shown to be effective in diagnosing muscle invasion of bladder cancer (BC) in primary patients. Purpose To evaluate the diagnostic efficacy of VI‐RADS in a BC target population which included post‐treatment patients, and to determine the repeatability. Study Type: Prospective. Population Seventy‐three patients (42 with primary BC, 31 with post‐treatment BC). Field Strength/Sequence: 3.0 T MRI with propeller fast spin‐echo T2WI, echo planer imaging diffusion‐weighted imaging (DWI), and dynamic contrast‐enhanced imaging (DCEI). Assessment VI‐RADS scores were independently assessed by five radiologists with different levels of experience. The diagnostic efficiency in each group (primary and post‐treatment) and of each radiologist was assessed. Statistical Tests: Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), and area under the curve (AUC) in receiver operating characteristic curve analysis were calculated to evaluate VI‐RADS diagnostic performance. Interobserver agreement was assessed using weighted Kappa statistics. A P value <0.05 was considered statistically significant. Results: At the corresponding cut‐off, AUC values of three groups range from 0.936 to 0.947 and AUC values of five observers range from 0.901 to 0.963. There was no significant difference between the AUCs in the primary and post‐treatment groups (P = 0.870). The cut‐off of the whole group and the post‐treatment group was ≥4, and the cut‐off of the primary group was ≥3. The Kappa values of interobserver agreements range from 0.709 to 0.923. Conclusions: After expanding the target population to include post‐treatment patients, VI‐RADS still has good diagnostic efficacy and repeatability. VI‐RADS could potentially be a preoperative staging tool for post‐treatment patients. Level of Evidence: 1 Technical Efficacy Stage: 2 [ABSTRACT FROM AUTHOR]

Objective: To quantitatively compare the diagnostic values of conventional diffusion-weighted imaging (DWI), intravoxel incoherent motion (IVIM), and diffusion kurtosis imaging (DKI) in differentiating between malignant and benign renal tumors.Methods: Multiple b value DWIs and DKIs were performed in 180 patients with renal tumors, which were divided into clear cell renal cell carcinoma (ccRCC), non-ccRCC, and benign renal tumor group. The apparent diffusion coefficient (ADC), true diffusivity (D), pseudo-diffusion coefficient (D*), perfusion fraction (f), mean kurtosis (MK), and mean diffusivity (MD) maps were calculated. The diagnostic efficacy of various diffusion parameters for predicting malignant renal tumors was compared.Results: The ADC, D, and MD values of ccRCCs were higher, while D*, f, and MK values were lower than those of benign renal tumors (all p < 0.025). The D* and f values of non-ccRCCs were lower than those of benign renal tumors (p = 0.002 and p < 0.001, respectively). The difference of ADC, D, MD, and MK values between non-ccRCCs and benign renal tumors was not statistically significant (p > 0.05). The ADC, D, MD, and f values of ccRCCs were higher, while MK values were lower than those of non-ccRCCs (all p < 0.001). The AUC values of ADC, D, D*, f, MK, and MD were 0.849, 0.891, 0.708, 0.656, 0.862, and 0.838 for differentiating ccRCCs from benign renal tumors, respectively. The AUC values of D* and f were 0.772 and 0.866 for discrimination between non-ccRCCs and benign renal tumors, respectively.Conclusion: IVIM parameters are the best, while DWI and DKI parameters have similar performance in differentiating malignant and benign renal tumors.Key Points: • The D value is the best parameter for differentiating ccRCC from benign renal tumors. • The f value is the best parameter for differentiating non-ccRCC from benign renal tumors. • Conventional DWI and DKI have similar performance in differentiating malignant and benign renal tumors. [ABSTRACT FROM AUTHOR]

Background: Because chronic kidney disease (CKD) is a worldwide problem, accurate pathological and functional evaluation is required for planning treatment and follow-up. Intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) can assess both capillary perfusion and tissue diffusion and may be helpful in evaluating renal function and pathology.Purpose: To evaluate functional and pathological alterations in CKD by applying IVIM-DWI.Study Type: Prospective study.Subjects: In all, 72 CKD patients who required renal biopsy and 20 healthy volunteers.Field Strength: 1.5T.Assessment: All subjects underwent IVIM-DWI of the kidneys, and image analysis was performed by two radiologists. The mean values of true diffusion coefficient (D), pseudo diffusion coefficient (D*), and perfusion fraction (f) were acquired from renal parenchyma. Correlation between IVIM-DWI parameters and estimated glomerular filtration rate (eGFR), as well as pathological damage, were assessed.Statistical Tests: One-way analysis of variance (ANOVA), paired sample t-test and Spearman correlation analysis.Results: The paired sample t-test revealed that IVIM-DWI parameters were significantly lower in medulla than cortex for both patients and controls (P < 0.01). Regardless of whether eGFR was reduced, ANOVA revealed that f values of renal parenchyma were significantly lower in patients than controls (P < 0.05). Spearman correlation analysis revealed that there were positive correlations between eGFR and D (cortex, r = 0.466, P < 0.001; medulla, r = 0.491, P < 0.001), and between eGFR and f (cortex, r = 0.713, P < 0.001; medulla, r = 0.512, P < 0.001). Negative correlations were found between f and glomerular injury (cortex, r = -0.773, P < 0.001; medulla, r = -0.629, P < 0.001), and between f and tubulointerstitial lesion (cortex, r = -0.728, P < 0.001; medulla, r = -0.547, P < 0.001).Data Conclusion: IVIM-DWI might be feasible for noninvasive evaluation of renal function and pathology of CKD, especially in detection of renal insufficiency at an early stage.Level Of Evidence: 1 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1251-1259. [ABSTRACT FROM AUTHOR]

Purpose To investigate the potential of Intravoxel incoherent motion diffusion-weighted imaging(IVIM-DWI) for the assessment of renal fibrosis in chronic kidney disease (CKD), using histopathology as a reference standard. Methods Eighty-five CKD patients and twenty healthy volunteers were recruited in this study. IVIM-DWI was performed in all of the participants, and all of the CKD patients underwent renal biopsy. The mean values of the true diffusion coefficient (D), pseudo diffusion coefficient (D*) and perfusion fraction (f) in the renal cortex and medulla were compared between the CKD patients and healthy volunteers. The Spearman correlation coefficient was calculated to assess the relationship between the D, D*,f values and the estimated glomerular filtration rate (eGFR), serum creatinine level (SCr), 24 h urinary protein level (24 h-UPRO), histopathological fibrosis scores. Results The D, D* and f values were significantly lower in medulla than in the cortex for all of the participants. All of the IVIM parameters were significantly lower in the CKD patients than in the healthy controls. In the CKD patients, a significant negative correlation was found between the renal parenchymal D, D*,f values and the 24 h–UPRO, as well as between the renal parenchymal D, f values and the SCr. There was a significant positive correlation between all of the IVIM parameters and the eGFR. All of the IVIM parameters exhibited a significant negative correlation with the histopathological fibrosis score. Conclusion IVIM-DWI shows great potential in the noninvasive assessment of renal fibrosis in CKD. [ABSTRACT FROM AUTHOR]

Background There has been a growing need for a sensitive and effective imaging method for the differentiation of the activity of ankylosing spondylitis (AS). Purpose To compare the performances of intravoxel incoherent motion (IVIM)-derived parameters and the apparent diffusion coefficient (ADC) for distinguishing AS-activity. Material and Methods One hundred patients with AS were divided into active (n = 51) and non-active groups (n = 49) and 21 healthy volunteers were included as control. The ADC, diffusion coefficient ( D), pseudodiffusion coefficient ( D*), and perfusion fraction ( f) were calculated for all groups. Kruskal-Wallis tests and receiver operator characteristic (ROC) curve analysis were performed for all parameters. Results There was good reproducibility of ADC /D and relatively poor reproducibility of D*/f. ADC, D, and f were significantly higher in the active group than in the non-active and control groups (all P < 0.0001, respectively). D* was slightly but significant lower in the active group than in the non-active and control group ( P = 0.0064, 0.0215). There was no significant difference in any parameter between the non-active group and the control group (all P > 0.050). In the ROC analysis, ADC had the largest AUC for distinguishing between the active group and the non-active group (0.988) and between the active and control groups (0.990). Multivariate logistic regression analysis models showed no diagnostic improvement. Conclusion ADC provided better diagnostic performance than IVIM-derived parameters in differentiating AS activity. Therefore, a straightforward and effective mono-exponential model of diffusion-weighted imaging may be sufficient for differentiating AS activity in the clinic. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the potential of diffusion kurtosis imaging (DKI) for the assessment of renal fibrosis in chronic kidney disease (CKD), using histopathology as the reference standard. Methods: Eighty-nine CKD patients and twenty healthy volunteers were recruited in this study. DKI was performed in all participants and all CKD patients received renal biopsy. The values of mean diffusivity (MD) and mean kurtosis (MK) in the renal cortex and medulla were compared between CKD patients and healthy volunteers. The Spearman correlation coefficient was calculated to assess the relationship between MD, MK values and the estimated glomerular filtration rate (eGFR), serum creatinine (SCr), 24 h urinary protein (24 h-UPRO), histopathological fibrosis score. Results: The medullary MD values were significantly lower than cortex, while the cortical MK values were significantly lower than medulla for all participants. Renal parenchymal MD values were significantly lower in the CKD patients than healthy controls, whereas MK values were significantly higher in the CKD patients than healthy controls. In the CKD patients, the significantly negative correlation was observed between the renal parenchymal MD values and the 24 h-UPRO, SCr, histopathological fibrosis score, as well as between the renal parenchymal MK values and the eGFR, while the significantly positive correlation was found between the renal parenchymal MD values and the eGFR, as well as between the renal parenchymal MK values and the 24 h-UPRO, SCr, histopathological fibrosis score. Conclusion: DKI shows great potential in the noninvasive assessment of renal fibrosis in CKD. [ABSTRACT FROM AUTHOR]

• O-RADS MRI risk stratification system could predict malignancy of adnexal masses. • The scoring system based on enhanced non-DCE MRI has excellent reproducibility. • Enhanced non-DCE MRI could perform well in evaluating adnexal malignancy. Evaluation of the diagnostic performance and reproducibility of the Ovarian-Adnexal Reporting and Data System (O-RADS) Magnetic Resonance Imaging (MRI) risk stratification system based on enhanced non-dynamic contrast-enhanced (non-DCE) MRI in the diagnosis of adnexal masses. Patients who underwent conventional pelvic enhanced non-DCE MRI examination within one month prior to surgery formed the study population. Two experienced radiologists independently evaluated the images and assigned a score according to the O-RADS MRI risk stratification system. One of the radiologists reviewed the images and reassigned the scores after three months. Intra- and inter-observer agreement was evaluated with the k coefficient value. The adnexal masses that attained scores between 1 and 3 were considered benign, while those with scores of 4 or 5 were considered malignant. Analyses were conducted to determine the sensitivity, specificity, positive and negative predictive values, and receiver operating characteristic (ROC) curve, which were then used for evaluating the diagnostic efficacy of the developed system based on enhanced non-DCE MRI scan. The reference standard was histology. A total of 308 patients (mean age: 42.09 ± 12.42 years, age range: 20–84 years) were enrolled in the study. Among the 362 adnexal masses from the included patients, there were 320 benign masses and 42 malignant masses. In the case of three readers, there were no malignant tumors scored 1–2. The O-RADS MRI score ≥ 4 was associated with malignancy resulted in a good diagnostic efficacy with the areas under the curve (AUC) values of 0.918 (95 % CI, 0.864–0.972), 0.905 (95 % CI, 0.842–0.968), and 0.882 (95 % CI, 0.815–0.950), the sensitivity values of 90.5 % (95 % CI, 87.5–93.5 %), 85.7 % (95 % CI, 82.1–89.3 %), and 83.3 % (95 % CI, 79.5–87.2 %), and the specificity values of 93.1 % (95 % CI, 90.5–95.7 %), 95.3 % (95 % CI, 93.1–97.5 %), and 93.1 % (95 % CI, 90.5–95.7 %) obtained for the three readers, respectively. Excellent intra-observer agreement and inter-observer agreement were observed with the k values of 0.883 (95 % CI, 0.814–0.952) and 0.848 (95 % CI, 0.770–0.926), respectively. The O-RADS MRI risk stratification system based on enhanced non-DCE MRI scans exhibited high accuracy and reproducibility in the prediction of adnexal masses malignancy. Enhanced non-DCE MRI scan may offer an alternative diagnostic tool when DCE is not possible. [ABSTRACT FROM AUTHOR]