Tissue characterization in the female pelvis by means of MR imaging

O-RADS scoring system for adnexal lesions: Diagnostic performance on TVUS performed by an expert sonographer and MRI

RATIONALE AND OBJECTIVE

To determine the diagnostic performance of transvaginal ultrasound (TVUS) performed by an US specialist and MRI based on the O-RADS scoring system.

MATERIALS AND METHODS

Between March 5th 2013 and December 31st 2021, 227 patients, referred to our center, underwent TVUS and pelvic MRI for characterization of an adnexal lesion proven by surgery or two years of negative follow-up. All lesions were classified according to O-RADS US and O-RADS MRI risk scoring systems. Imaging data were then correlated with histopathological diagnosis or negative follow-up for 2 years.

RESULTS

The prevalence of malignancy was 11.1%. Sensitivity of O-RADS US / O-RADS MRI were respectively of 83.3%/83.3% and specificity was 73.2%/92.9% (p < 0.001). O-RADS MRI was more accurate than O-RADS US even when performed by an US specialist (p < 0.001). When MRI was used after US, 51 lesions were reclassified correctly by MRI and only 4 lesions incorrectly reclassified. Most of the lesions (49/51) rated O-RADS US 4 or 5 and reclassified correctly by MRI were benign, mainly including cystadenomas or cystadenofibromas. Only 4 lesions were misclassified by MRI but correctly classified by ultrasound.

CONCLUSION

Our study suggests that MR imaging has equally high sensitivity but higher specificity than TVUS for the characterization of adnexal lesions based on O-RADS scoring system. MRI should be the recommended second-line technique when a mass is discovered during TVUS and is rated O-RADS 4 and 5 over than TVUS by an US specialist.

Impact of MRI on the post-therapeutic diagnosis of T4 esophageal cancer

BACKGROUND

Opportunities for T4b esophageal cancer patients to receive curative surgery are increasing with the development of multidisciplinary treatments. However, the best modality to accurately diagnose infiltration to the organs surrounding T4b esophageal cancer is still unknown. The aim of this study was to determine the performance of CT and MRI in diagnosing T stage in T4b esophageal cancer, with reference to the pathological diagnosis.

METHODS

A retrospective medical records review of patients with T4b esophageal cancer patients from January 2017 to December 2021 was conducted. Among 125 patients who were treated for cT4b esophageal cancer in Osaka University Hospital, 30 patients were diagnosed with cT4b esophageal cancer by CT, ycT staging with CT (contrast-enhanced images) and MRI (T2-FSE images), and curative R0 resection was performed. Preoperative MRI staging was independently performed by two experienced radiologists. The diagnostic performance of CT and MRI were examined using McNemar's test.

RESULTS

Nineteen and 12 patients were diagnosed with ycT4b by CT and MRI, respectively. Combined T4b organ resection was performed in 15 patients. A pathological diagnosis of ypT4b was made in 11 cases. In comparison to CT, MRI showed a higher diagnostic performance, specificity (47% vs. 89%, p = 0.013), and accuracy (60% vs. 90%, p = 0.015) for CT vs. MRI.

CONCLUSIONS

Our results-with reference to the pathological diagnosis-revealed that MRI had a superior diagnostic performance to CT for diagnosing T4b esophageal cancer invading the surrounding organs. An accurate diagnosis of T4b esophageal cancer may facilitate the implementation of appropriate treatment strategies.

Attention feature fusion methodology with additional constraint for ovarian lesion diagnosis on magnetic resonance images

PURPOSE

It is challenging for radiologists and gynecologists to identify the type of ovarian lesions by reading magnetic resonance (MR) images. Recently developed convolutional neural networks (CNNs) have made great progress in computer vision, but their architectures still need modification if they are used in processing medical images. This study aims to improve the feature extraction capability of CNNs, thus promoting the diagnostic performance in discriminating between benign and malignant ovarian lesions.

METHODS

We introduce a feature fusion architecture and insert the attention models in the neural network. The features extracted from different middle layers are integrated with reoptimized spatial and channel weights. We add a loss function to constrain the additional probability vector generated from the integrated features, thus guiding the middle layers to emphasize useful information. We analyzed 159 lesions imaged by dynamic contrast-enhanced MR imaging (DCE-MRI), including 73 benign lesions and 86 malignant lesions. Senior radiologists selected and labeled the tumor regions based on the pathology reports. Then, the tumor regions were cropped into 7494 nonoverlapping image patches for training and testing. The type of a single tumor was determined by the average probability scores of the image patches belonging to it.

RESULTS

We implemented fivefold cross-validation to characterize our proposed method, and the distribution of performance matrics was reported. For all the test image patches, the average accuracy of our method is 70.5% with an average area under the curve (AUC) of 0.785, while the baseline is 69.4% and 0.773, and for the diagnosis of single tumors, our model achieved an average accuracy of 82.4% and average AUC of 0.916, which were better than the baseline (81.8% and 0.899). Moreover, we evaluated the performance of our proposed method utilizing different CNN backbones and different attention mechanisms.

CONCLUSIONS

The texture features extracted from different middle layers are crucial for ovarian lesion diagnosis. Our proposed method can enhance the feature extraction capabilities of different layers of the network, thereby improving diagnostic performance.

How to improve O-RADS MRI score for rating adnexal masses with cystic component?

OBJECTIVES

To test the performance of the Ovarian-Adnexal Reporting Data System (O-RADS) MRI in characterizing adnexal masses with cystic components and to test new specific MRI features related to cystic components to improve the ability of the O-RADS MRI score to stratify lesions according to their risk of malignancy.

METHODS

The EURopean ADnexal study (EURAD) database was retrospectively queried to identify adnexal masses with a cystic component. One junior and 13 radiologists independently reviewed cases blinded to the pathological diagnosis. For each lesion, the size of the whole lesion, morphological appearance, number of loculi, presence of a thickened wall, thickened septae, signal intensity of the cystic components on T1-weighted/T2-weighted/diffusion weighted, mean value of the apparent diffusion coefficient, and O-RADS MRI score were reported. Univariate and multivariate logistic regression analysis was performed to determine significant features to predict malignancy.

RESULTS

The final cohort consisted of 585 patients with 779 pelvic masses who underwent pelvic MRI to characterize an adnexal mass(es). Histology served as the standard of reference. The diagnostic performance of the O-RADS MRI score was 0.944, 95%CI [0.922-0.961]. Significant criteria associated with malignancy included an O-RADS MRI score ≥ 4, ADCmean of cystic component > 1.69, number of loculi > 3, lesion size > 75 mm, the presence of a thick wall, and a low T1-weighted, a high T2-weighted, and a low diffusion-weighted signal intensity of the cystic component. Multivariate analysis demonstrated that an O-RADS MRI score ≥ combined with an ADC mean of the cystic component > 1.69, size > 75 mm, and low diffusion-weighted signal of the cystic component significantly improved the diagnostic performance up to 0.958, 95%CI [0.938-0.973].

CONCLUSION

Cystic component analysis may improve the diagnosis performance of the O-RADS MRI score in adnexal cystic masses.

KEY POINTS

• O-RADS MRI score combined with specific cystic features (area under the receiving operating curve, AUROC = 0.958) improves the diagnostic performance of the O-RADS MRI score (AUROC = 0.944) for predicting malignancy in this cohort. • Cystic features that improve the prediction of malignancy are ADC mean > 1.69 (OR = 7); number of loculi ≥ 3 (OR = 5.16); lesion size > 75 mm (OR = 4.40); the presence of a thick wall (OR = 3.59); a high T2-weighted signal intensity score 4 or 5 (OR = 3.30); a low T1-weighted signal intensity score 1, 2, or 3 (OR = 3.45); and a low diffusion-weighted signal intensity (OR = 2.12). • An adnexal lesion with a cystic component rated O-RADS MRI score 4 and an ADC value of the cystic component < 1.69 associated with a low diffusion-weighted signal, has virtually a 0% risk of malignancy.

T2-weighted imaging hypointensity in an ovarian lesion: is it a benign finding?

Objective

To evaluate whether the presence of a hypointense signal at T2-weighted imaging in a solid ovarian lesion on magnetic resonance imaging is a predictor of stability and benignity.

Methods

This is a single center study, prospectively read with retrospective acquired data. The database was searched for patients who underwent magnetic resonance imaging between January 2008 and October 2019 and whose reports mentioned solid ovarian lesions with low signal on T2-weighted imaging. A total of 47 nodules were included. A radiologist who was blinded to the clinical indication for magnetic resonance imaging and original reports evaluated the cases. Objective and subjective criteria of ovarian lesions in magnetic resonance imaging were evaluated.

Results

Thirty-five nodules were considered benign/stable and 12 were considered non-stable. The analysis showed that the non-stable lesions showed statistically more hyperintensity at T1-weighted imaging compared to the stable lesions.

Conclusion

T2-weighted imaging hypointensity can be considered a predictor of stability in solid ovarian lesions when associated with iso/hypointensity in T1-weighted imaging.

O-RADS MRI Risk Stratification System: Guide for Assessing Adnexal Lesions from the ACR O-RADS Committee

MRI plays an important role as a secondary test or problem-solving modality in the evaluation of adnexal lesions depicted at US. MRI has increased specificity compared with US, decreasing the number of false-positive diagnoses for malignancy and thereby avoiding unnecessary or over-extensive surgery in patients with benign lesions or borderline tumors, while women with possible malignancies can be expeditiously referred for oncologic surgical evaluation. The Ovarian-Adnexal Reporting and Data System (O-RADS) MRI Committee is an international collaborative effort formed under the direction of the American College of Radiology and includes a diverse group of experts on adnexal imaging and management who developed the O-RADS MRI risk stratification system. This scoring system assigns a probability of malignancy based on the MRI features of an adnexal lesion and provides information to facilitate optimal patient management. The widespread implementation of a codified reporting system will lead to improved interpretation agreement and standardized communication between radiologists and referring physicians. In addition, it will allow for high-quality multi-institutional collaborations-an important unmet need that has hampered the performance of high-quality research in this area in the past. This article provides guidelines on using the O-RADS MRI risk stratification system in clinical practice, as well as in the educational and research settings.

MRI in the Diagnosis of Endometriosis and Related Diseases

Endometriosis, a common chronic inflammatory disease in female of reproductive age, is closely related to patient symptoms and fertility. Because of its high contrast resolution and objectivity, MRI can contribute to the early and accurate diagnosis of ovarian endometriotic cysts and deeply infiltrating endometriosis without the need for any invasive procedure or radiation exposure. The ovaries, which are the most frequent site of endometriosis, can be afflicted by multiple related conditions and diseases. For the diagnosis of deeply infiltrating endometriosis and secondary adhesions among pelvic organs, fibrosis around the ectopic endometrial gland is usually found as a T2 hypointense lesion. This review summarizes the MRI findings obtained for ovarian endometriotic cysts and their physiologically and pathologically related conditions. This article also includes the key imaging findings of deeply infiltrating endometriosis.

Diagnostic Value of DCE-MRI for Differentiating Malignant Adnexal Masses Compared with Contrast-enhanced-T1WI

PURPOSE

To compare the diagnostic performance of dynamic contrast-enhanced-MR (DCE-MR) and delayed contrast-enhanced (CE)-MRI added to unenhanced MRI, including diffusion weighted image (DWI) for differentiating malignant adnexal tumors, conducting a retrospective blinded image interpretation study.

METHODS

Data of 80 patients suspected of having adnexal tumors by ultrasonography between April 2008 and August 2018 were used for the study. All patients had undergone preoperative MRI and surgical resection at our institution. Four radiologists (two specialized in gynecological radiology and two non-specialized) were enrolled for blinded review of the MR images. A 3-point scale was used: 0 = benign, 1 = indeterminate, and 2 = malignant. Three imaging sets were reviewed: Set A, unenhanced MRI including DWI; Set B, Set A and delayed CE-T1WI; and Set C, Set A and DCE-MRI. Imaging criteria for benign and malignant tumors were given in earlier reports. The diagnostic performance of the three imaging sets of the four readers was calculated. Their areas under the curve (AUCs) were compared using the DeLong method.

RESULTS

Accuracies of Set B were 81%-88%. Those of Set C were 81%-85%. The AUCs of Set B were 0.83 and 0.89. Those of Set C were 0.81-0.86. For two readers, Set A showed lower accuracy and AUC than Set B/Set C (less than 0.80), although those were equivalent in other readers. No significant difference in AUCs was found among the three sequence sets. Intrareader agreement was moderate to almost perfect in Sets A and B, and substantial to almost perfect in Set C.

CONCLUSION

DCE-MR showed no superiority for differentiating malignant adnexal tumors from benign tumors compared to delayed CE-T1WI with conventional MR and DWI.

Differentiation of Endometriomas from Hemorrhagic Cysts at Magnetic Resonance: The Role of Quantitative Signal Intensity Measurements

BACKGROUND

Endometriomas and functional hemorrhagic cysts (FHCs) are a common gynecological encounter.

OBJECTIVE

This study aimed to assess the diagnostic efficiency of magnetic resonance imaging (MRI) using signal intensity measurements in differentiating endometriomas from FHCs.

METHODS

Forty-six patients who underwent pelvic MRI examinations (endometriomas, n=28; FHCs, n=18) were retrospectively included. The "T2 shading" sign was evaluated subjectively and quantitatively by measuring the T1-T2 signal intensity difference and calculating the percentage of signal decrease between T1 and T2-weighted sequences. The resulted values, along with the measurement of the Apparent Diffusion Coefficient (ADC) and the signal intensity on three diffusion- weighted sequences (DWI) (b⁵⁰, b⁴⁰⁰, and b⁸⁰⁰), were compared between groups by using the Mann-Whitney U test. Also, the receiver operating characteristic analysis was performed for the statistically significant results (P<0.016), and the area under the curve (AUC) was also calculated.

RESULTS

The two quantitative assessment methods showed similar efficiency in detecting endometriomas (P<0.001; sensitivity, 100%; specificity, 81.82%; AUC>0.86), outperforming the classic subjective evaluation of the "T2 shading" sign (sensitivity, 92.86%; specificity, 66.67%). ADC (P=0.52) and DWI measurements (P=0.49, P=0.74, and P=0.78) failed to distinguish between the two entities.

CONCLUSION

The quantitative analysis and interpretation of the "T2 shading" sign can significantly improve the differential diagnosis between endometriomas and FHCs.

Adnexal masses characterized on 3 tesla magnetic resonance imaging - added value of diffusion techniques

Background

To assess different types of adnexal masses as identified by 3T MRI and to discuss the added value of diffusion techniques compared with conventional sequences.

Patients and methods

174 women age between 13 and 87 underwent an MRI examination of the pelvis for a period of three years. Patients were examined in two radiology departments – 135 of them on 3 Tesla MRI Siemens Verio and 39 on 3 Tesla MRI Philips Ingenia. At least one adnexal mass was diagnosed in 98 patients and they are subject to this study. Some of them were reviewed retrospectively. Data from patients’ history, physical examination and laboratory tests were reviewed as well.

Results

124 ovarian masses in 98 females’ group of average age 47.2 years were detected. Following the MRI criteria, 59.2% of the cases were considered benign, 30.6% malignant and 10.2% borderline. Out of all masses 58.1% were classified as cystic, 12.9% as solid and 29% as mixed. Оf histologically proven tumors 74.4% were benign and 25.6% were malignant. All of the malignant tumors had restricted diffusion. 64 out of all patients underwent contrast enhancement. (34 there were a subject of contraindications). 39 (61%) of the masses showed contrast enhancement.

Conclusions

Classifying adnexal masses is essential for the preoperative management of the patients. 3T MRI protocols, in particular diffusion techniques, increase significantly the accuracy of the diagnostic assessment.

Evaluation of a convolutional neural network for ovarian tumor differentiation based on magnetic resonance imaging

OBJECTIVES

There currently lacks a noninvasive and accurate method to distinguish benign and malignant ovarian lesion prior to treatment. This study developed a deep learning algorithm that distinguishes benign from malignant ovarian lesion by applying a convolutional neural network on routine MR imaging.

METHODS

Five hundred forty-five lesions (379 benign and 166 malignant) from 451 patients from a single institution were divided into training, validation, and testing set in a 7:2:1 ratio. Model performance was compared with four junior and three senior radiologists on the test set.

RESULTS

Compared with junior radiologists averaged, the final ensemble model combining MR imaging and clinical variables had a higher test accuracy (0.87 vs 0.64, p < 0.001) and specificity (0.92 vs 0.64, p < 0.001) with comparable sensitivity (0.75 vs 0.63, p = 0.407). Against the senior radiologists averaged, the final ensemble model also had a higher test accuracy (0.87 vs 0.74, p = 0.033) and specificity (0.92 vs 0.70, p < 0.001) with comparable sensitivity (0.75 vs 0.83, p = 0.557). Assisted by the model's probabilities, the junior radiologists achieved a higher average test accuracy (0.77 vs 0.64, Δ = 0.13, p < 0.001) and specificity (0.81 vs 0.64, Δ = 0.17, p < 0.001) with unchanged sensitivity (0.69 vs 0.63, Δ = 0.06, p = 0.302). With the AI probabilities, the junior radiologists had higher specificity (0.81 vs 0.70, Δ = 0.11, p = 0.005) but similar accuracy (0.77 vs 0.74, Δ = 0.03, p = 0.409) and sensitivity (0.69 vs 0.83, Δ = -0.146, p = 0.097) when compared with the senior radiologists.

CONCLUSIONS

These results demonstrate that artificial intelligence based on deep learning can assist radiologists in assessing the nature of ovarian lesions and improve their performance.

KEY POINTS

• Artificial Intelligence based on deep learning can assess the nature of ovarian lesions on routine MRI with higher accuracy and specificity than radiologists. • Assisted by the deep learning model's probabilities, junior radiologists achieved better performance that matched those of senior radiologists.

IDEAL study: magnetic resonance imaging for suspected deep endometriosis assessment prior to laparoscopy is as reliable as radiological imaging as a complement to transvaginal ultrasonography

OBJECTIVE

To compare the value of using one-stop magnetic resonance imaging (MRI) vs standard radiological imaging as a supplement to transvaginal ultrasonography (TVS) for the preoperative assessment of patients with endometriosis referred for surgery in a tertiary care academic center.

METHODS

This prospective observational study compared the diagnostic value of the standard preoperative imaging practice of our center, which involves expert TVS complemented by intravenous urography (IVU) for the evaluation of the ureters and double-contrast barium enema (DCBE) for the evaluation of the rectum, sigmoid and cecum, with that of expert TVS complemented by a 'one-stop' MRI examination evaluating the upper abdomen, pelvis, kidneys and ureters as well as rectum and sigmoid on the same day, for the preoperative triaging of 74 women with clinically suspected deep endometriosis. The findings at laparoscopy were considered the reference standard. Patients were stratified according to their need for monodisciplinary surgical approach, carried out by gynecologists only, or multidisciplinary surgical approach, involving abdominal surgeons and/or urologists, based on the extent to which endometriosis affected the reproductive organs, bowel, ureters, bladder or other abdominal organs.

RESULTS

Our standard preoperative imaging approach and the combined findings of TVS and MRI had similar diagnostic performance, resulting in correct stratification for a monodisciplinary or a multidisciplinary surgical approach of 67/74 (90.5%) patients. However, there were differences between the estimation of the severity of disease by DCBE and MRI. The severity of rectal involvement was underestimated in 2.7% of the patients by both TVS and DCBE, whereas it was overestimated in 6.8% of the patients by TVS and/or DCBE.

CONCLUSIONS

Complementary to expert TVS, 'one-stop' MRI can predict intraoperative findings equally well as standard radiological imaging (IVU and DCBE) in patients referred for endometriosis surgery in a tertiary care academic center. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Validity and Reproducibility of the ADNEX MR Scoring System in the Diagnosis of Sonographically Indeterminate Adnexal Masses

BACKGROUND

The diagnosis of sonographically indeterminate adnexal masses (AM) signifies a major challenge in clinical practice. Early detection and characterization have increased the need for accurate imaging evaluation before treatment.

PURPOSE

To assess the validity and reproducibility of the ADNEX MR Scoring system in the diagnosis of sonographically indeterminate AM.

STUDY TYPE

A prospective multicenter study.

POPULATION

In all, 531 women (mean age, 44 ± 11.2 years; range, 21-79 years) with 572 sonographically indeterminate AM.

FIELD STRENGTH/SEQUENCE

1.5T/precontrast T₁ -weighted imaging (WI) fast spin echo (FSE) (in-phase and out-of-phase, with and without fat suppression); T₂ -WI FSE; diffusion-WI single-shot echo planner with b-values of 0 and 1000 s/mm² ; and dynamic contrast-enhanced perfusion T₁ -WI liver acquisition with volume acceleration (LAVA).

ASSESSMENT

All MRI examinations were evaluated by three radiologists, and the AM were categorized into five scores based on the ADNEX MR Scoring system. Score 1: no AM; 2: benign AM; 3: probably benign AM; 4: indeterminate AM; 5: probably malignant AM. Histopathology and imaging follow-up were used as the standard references for evaluating the validity of the ADNEX MR Scoring system for detecting ovarian malignancy.

STATISTICAL TESTS

Four-fold table test, kappa statistics (κ), and receiver operating characteristic (ROC) curve.

RESULTS

In all, 136 (23.8%) AM were malignant, and 436 (76.2%) were benign. Of the 350 AM classified as score 2, one (0.3%) was malignant; of the 62 AM classified as score 3, six (9.7%) were malignant; of the 73 AM classified as score 4, 43 (58.9%) were malignant; and of the 87 AM categorized as score 5, 86 (98.9%) were malignant. The best cutoff value for predicting malignant AM was score >3 with sensitivity and specificity of 92.9% and 94.9%, respectively. The interreader agreement of the ADNEX MR Scoring was very good (κ = 0.861).

DATA CONCLUSION

The current study supports the high validity and reproducibility of the ADNEX MR Scoring system for the diagnosis of sonographically indeterminate AM.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 2.

Imaging findings of cesarean delivery complications: cesarean scar disease and much more

In the last years, there has been a significant increase in the number of cesarean deliveries and, with it, of the number of complications following the procedure. They can be divided into early and late ones. We will illustrate herein the most common complications following cesarean section to help radiologists to recognize them. To familiarize with these various pathologic conditions is crucial to alert referring clinicians for a prompt and appropriate maternal and fetal management. Special attention will be given to the cesarean scar defect (CSD), the most common but also the most unknown of such conditions. Although often asymptomatic, a severe CSD represents a predisposing factor for subsequent complications especially in future pregnancies.

Systematic radiological approach to utero-ovarian pathologies

Ultrasound is the first-line imaging modality for the evaluation of suspected adnexal masses, endometriosis and uterine tumors, whereas MRI is used as a secondary diagnostic tool to better characterize these lesions. The aim of this review is to summarize the latest advances in the imaging of these utero-ovarian pathologies.

A case report and a literature review of primary retroperitoneal mucinous cystadenoma: the importance of imaging in diagnosis and management

Primary retroperitoneal mucinous cystadenoma (PRMC) is an extremely rare tumor: its histogenesis and its biological behavior remain speculative. Since most retroperitoneal tumors are malignant, a preoperative diagnosis of benignity is essential and it can be reached through imaging examinations, allowing a conservative management approach. We describe the case of a 52-year-old woman with abdominal pain and a palpable mass. Computed tomography of the abdomen revealed a retroperitoneal cystic mass, which was resected successfully through laparoscopy and diagnosed as PRMC. Although there are no pathognomonic, clinical or radiological findings for PRMC, it should be included in the list of differential diagnoses and its imaging criteria of benignity should always be sought, with the aim to exclude malignant tumors.

Role of 18F-FDG PET/CT in restaging and follow-up of patients with uterine sarcomas

PURPOSE

Uterine sarcomas are rare tumors with poor prognosis due to the high recurrence rates. The current role of ¹⁸F-FDG PET/CT in the post-therapy surveillance is not established yet.

MATERIALS AND METHODS

Forty-one women with uterine sarcoma underwent 73 ¹⁸F-FDG PET/CT for restaging in suspected recurrence or during follow-up in asymptomatic patients. Histopathology results and/or clinical/imaging follow-up for at least 12 months were considered the reference standard. The diagnostic accuracy and clinical impact of ¹⁸F-FDG PET/CT was calculated.

RESULTS

Thirty-three ¹⁸F-FDG PET/CT were positive, while the remaining 40 studies were negative. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of ¹⁸F-FDG PET/CT were 88%, 98%, 97%, 91% and 93%, respectively. Considering patients with clinical or radiological suspicion of recurrence (n=47) and those during follow-up (n=26), sensitivity, specificity, PPV, NPV and accuracy of ¹⁸F-FDG PET/CT were 89%, 100%, 100%, 86% and 94%, and 80%, 95%, 80%, 95% and 92%, respectively. ¹⁸F-FDG PET/CT had a positive clinical impact in 9/73 (12%) studies and changed the clinical management in 8/41 (20%) patients.

CONCLUSIONS

¹⁸F-FDG PET/CT seems to be an accurate method for detection and localization of local and distant recurrence in patients with uterine sarcoma with good sensitivity and specificity and significant impact on clinical decision making.

Utility of DWI with quantitative ADC values in ovarian tumors: a meta-analysis of diagnostic test performance

Background Diffusion-weighted imaging (DWI) and quantitative apparent diffusion coefficient (ADC) values are widely used in the differential diagnosis of ovarian tumors. Purpose To assess the diagnostic performance of quantitative ADC values in ovarian tumors. Material and Methods PubMed, Embase, the Cochrane Library, and local databases were searched for studies assessing ovarian tumors using quantitative ADC values. We quantitatively analyzed the diagnostic performances for two clinical problems: benign vs. malignant tumors and borderline vs. malignant tumors. We evaluated diagnostic performances by the pooled sensitivity and specificity values and by summary receiver operating characteristic (SROC) curves. Subgroup analyses were used to analyze study heterogeneity. Results From the 742 studies identified in the search results, 16 studies met our inclusion criteria. A total of ten studies evaluated malignant vs. benign ovarian tumors and six studies assessed malignant vs. borderline ovarian tumors. Regarding the diagnostic accuracy of quantitative ADC values for distinguishing between malignant and benign ovarian tumors, the pooled sensitivity and specificity values were 0.91 and 0.91, respectively. The area under the SROC curve (AUC) was 0.96. For differentiating borderline from malignant tumors, the pooled sensitivity and specificity values were 0.89 and 0.79, and the AUC was 0.91. The methodological quality of the included studies was moderate. Conclusion Quantitative ADC values could serve as useful preoperative markers for predicting the nature of ovarian tumors. Nevertheless, prospective trials focused on standardized imaging parameters are needed to evaluate the clinical value of quantitative ADC values in ovarian tumors.

A systematic approach to adnexal masses discovered on ultrasound: the ADNEx MR scoring system

Adnexal lesions are a common occurrence in radiology practice and imaging plays a crucial role in triaging women appropriately. Current trends toward early detection and characterization have increased the need for accurate imaging assessment of adnexal lesions prior to treatment. Ultrasound is the first-line imaging modality for assessing adnexal lesions; however, approximately 20% of lesions are incompletely characterized after ultrasound evaluation. Secondary assessment with MR imaging using the ADNEx MR Scoring System has been demonstrated as highly accurate in the characterization of adnexal lesions and in excluding ovarian cancer. This review will address the role of MR imaging in further assessment of adnexal lesions discovered on US, and the utility of the ADNEx MR Scoring System.

MRI findings in deep infiltrating endometriosis: A pictorial essay

Endometriosis is an important gynaecological disorder which can impact significantly on an individual's quality of life and has major implications on fertility. Deep infiltrating endometriosis is a severe form of endometriosis which can cause obliteration of anatomic compartments. Laparoscopy remains the gold standard for diagnosis of endometriosis, although is an invasive procedure that has the potential to be hindered by obliterative disease. Ultrasound is often employed as the first-line imaging modality when endometriosis is suspected, however, MRI is more accurate in assessment of complex disease. Pre-operative MRI is highly specific in the diagnosis of endometriosis and characterization of disease extent, and plays a key role in guiding surgical management. MRI findings in deep infiltrating endometriosis are described.

Role of Imaging in Fertility-sparing Treatment of Gynecologic Malignancies

Treatments for gynecologic cancer usually result in loss of fertility due to surgery or radical radiation therapy in the pelvis. In countries with an established screening program for cervical cancer, the majority of gynecologic malignancies occur in postmenopausal women. However, a substantial number of affected women are of childbearing age and have not completed their families. In these younger women, consideration of fertility preservation may be important. This article describes the fertility-sparing treatment options that are currently available and outlines the role of imaging in the selection of eligible patients on the basis of a review of the literature. In the setting of cervical cancer, magnetic resonance (MR) imaging is used to delineate the size, position, and stage of the tumor for selection of patients who are suitable for radical trachelectomy. In patients with solitary complex adnexal masses, diffusion- and perfusion-weighted MR imaging sequences are used to categorize the likelihood of invasive or borderline malignancy for consideration of unilateral ovarian resection, with fertility preservation when possible. In patients with endometrial cancer, MR imaging is used to rule out signs of invasive disease before hormone therapy is considered. Imaging is also used at patient follow-up to detect recurrent disease; however, evidence to support this application is limited. In conclusion, imaging is an essential tool in the care of patients with gynecologic malignancies who are considering fertility-preserving treatment options. ^©RSNA, 2016.

Review of paratesticular pathology: findings on ultrasound and MRI

The paratesticular scrotal contents consist of the spermatic cord, epididymis, and fascia, which originate from the embryologic descent of the testis through the abdominal wall. Historically, the primary diagnostic modality has been high-resolution ultrasound. Magnetic resonance imaging (MRI) is an alternative imaging option. Both contrast MRI and diffusion weighted imaging can assist in differentiating between benign and malignant lesions. Unlike the testis which most disease processes are malignant, a wide spectrum of benign disease processes affects the paratesticular region either in isolation or as part of a contiguous disease process from adjacent organs. The familiarity with the epidemiology, pathogenesis, and imaging features can aid the radiologic diagnoses and guide appropriate clinical management. In this article, we review the ultrasound and MR characteristics of various paratesticular pathologies.

The shading sign: is it exclusive of endometriomas?

OBJECTIVES

To investigate if the shading sign is an exclusive MRI feature of endometriomas or endometrioid tumors, and to analyze its different patterns.

METHODS

Three hundred and fourty six women with adnexal masses who underwent 1.5/3-T MRI were included in this retrospective, board-approved study. The shading sign was found in 56 patients, but five cases were excluded due to lack of imaging follow-up or histological correlation. The final sample included 51 women. The type of tumor and the pattern of shading were recorded for each case.

RESULTS

Thirty endometriomas and five endometrioid carcinomas were found. The remaining 16 cases corresponded to other benign and malignant tumors. The overall sensitivity, specificity, positive predictive value, and negative predictive value were 73%, 93%, 59%, and 96%, respectively. Restricting the analysis to cystic lesions without solid or fat component, sensitivity, specificity, positive predictive value, and negative predictive value were 73%, 96%, 94%, and 80%. Five shading patterns were identified: layering (15.7%), liquid-liquid level (11.8%), homogenous (45.1%), heterogeneous (11.8%), and focal/multifocal shading within a complex mass (19.6%). No significant correlation was found between these patterns and the type of tumor.

CONCLUSIONS

The shading sign is not exclusive of endometriomas or endometrioid tumors. Homogenous shading was the most prevalent pattern in endometriomas and half of the cases with focal/multifocal shading within a complex mass were endometrioid carcinomas.

Magnetic resonance imaging evaluation of non ovarian adnexal lesions

Differentiation of nonovarian from ovarian lesions is a diagnostic challenge. MRI (Magnetic Resonance Imaging) of the pelvis provides excellent tissue characterization and high contrast resolution, allowing for detailed evaluation of adnexal lesions. Salient MRI characteristics of predominantly cystic lesions and predominantly solid adnexal lesions are presented along with epidemiology and clinical presentation. Due to its excellent soft tissue resolution, MRI may be able to characterize indeterminate adnexal masses and aid the radiologist to arrive at the correct diagnosis, thus positively affect patient management.

Added Value of Assessing Adnexal Masses with Advanced MRI Techniques

This review will present the added value of perfusion and diffusion MR sequences to characterize adnexal masses. These two functional MR techniques are readily available in routine clinical practice. We will describe the acquisition parameters and a method of analysis to optimize their added value compared with conventional images. We will then propose a model of interpretation that combines the anatomical and morphological information from conventional MRI sequences with the functional information provided by perfusion and diffusion weighted sequences.

MR characterization of focal liver lesions: pearls and pitfalls

Magnetic resonance (MR) can characterize specific tissue subtypes, thus facilitating focal liver lesion diagnosis. Focal liver lesions that are isointense to hyperintense to liver on T1-weighted images are usually hepatocellular in origin. Chemical shift imaging can narrow the differential diagnosis by detecting the presence of lipid or iron. T2 and heavily T2-weigthed fast spin echo imaging can differentiate solid from nonsolid focal liver lesions. The authors illustrate these MR imaging pearls and the uncommon exceptions (pitfalls). The authors hope that you will find this less traditional contribution to the Magnetic Resonance Clinics of North America helpful in clinical practice.

Imaging Diagnosis of Urethral Leiomyoma, usual Tumour at an Unusual Location

Leiomyomas are benign tumours of smooth muscle origin and are the most common uterine masses in females of reproductive age group. Extrauterine leiomyomas are also encountered occassionally and most commonly they involve the genitourinary tract. Leiomyomas arising from urethral smooth muscle are exceptionally unusual which can pose a diagnostic dilemma. Patients usually present with urinary complaints and an intraluminal soft tissue mass bulging from urethral meatus. We are presenting the imaging findings of leiomyoma of distal urethra presenting as a perineal mass with histopathological correlation.

Necrotizing ruptured vaginal leiomyoma mimicking a malignant neoplasm

Leiomyomas are common benign uterine tumors. However, the incidence of vaginal myoma is very rare and may be confused with a variety of vaginal tumors. We report a case of 43-year-old nulligravida who presented with a protruding painful vaginal mass for 7 days. The mass had initially appeared 3 years prior, as 2 to 3 cm that had not subsequently increased. However suddenly, there was rapid severe enlargement over the course of 7 days. Physical exam revealed a monstrous shaped, black color with focal necrosis, odorous protruding vaginal mass about 7 cm in size. The vaginal mass was infected and degenerated. And vaginal wall was also destroyed by the enlarged mass. Because of the clinical features and radiologic findings, the preoperative diagnosis was a vaginal malignancy. We reported an extremely rare case of vaginal myoma that had several characteristics of malignancy, with a brief review of the literature.

Lesions of the ovary with T1-hypersignal

Pelvic magnetic resonance imaging (MRI) has been used successfully to diagnose ovarian masses that cannot be adequately evaluated using pelvic ultrasound. T1 hyperintensity is a common finding in an ovarian mass and has important diagnostic implications. The aims of this review are to list the substances that may produce high signal intensity on T1-weighted MRI, to explain the physical basis for causes of the high T1 signal intensity, and to describe common and uncommon T1 hyperintense ovarian lesions. The morphological findings, the imaging features of the additional sequences, and clinical variables can help in the differential diagnosis, and in some cases, enable a specific diagnosis, leading to appropriate management of the patient.

Practical approach to MRI of female pelvic masses

OBJECTIVE

Female pelvic masses have a broad differential diagnosis, including benign and malignant neoplasms and nonneoplastic entities.

CONCLUSION

By using a systematic approach to the evaluation of a complex pelvic mass, including incorporating the clinical and surgical history, and by using multiparametric MRI to identify the anatomic origin, morphologic features, and tissue composition of a mass, a short meaningful differential diagnosis or definitive diagnosis can often be established.