Placental functional assessment and its relationship to adverse pregnancy outcome: comparison of intravoxel incoherent motion (IVIM) MRI, T2-relaxation time, and umbilical artery Doppler ultrasound.

BACKGROUND: Early identification of placental insufficiency can lead to appropriate treatment selections and can improve neonates' outcomes. Possible contributions of magnetic resonance imaging (MRI) have been suggested. PURPOSE: To evaluate the prognostic capabilities of placental intravoxel incoherent motion (IVIM) parameters and T2-relaxation time, and their correlation with fetal growth and adverse outcomes, comparing umbilical artery (UmA) pulsatility index (PI). MATERIAL AND METHODS: A total of 68 singleton pregnancies at 24-40 weeks of gestation underwent placental MRI and were reviewed retrospectively. UmA-PI was measured using Doppler ultrasound by obstetricians. IVIM parameters (Dfast, Dslow, and f) were calculated with a Bayesian model fitting. First, the associations between gestational age (GA) with placental IVIM parameters, T2-relaxation time, and placental thickness (PT) were evaluated. Second, IVIM parameters, T2 value (Z-score), PT (Z-score), and UmA-PI (Z-score) were compared between ( 1) those delivering small for gestational age (SGA) and appropriate for gestational age (AGA) neonates, ( 2) emergency cesarean section (ECS), and non-ECS, and ( 3) preterm birth and full-term birth. RESULTS: Low birth weight was observed in 15/68 cases (22%). GA was significantly associated only with T2-relaxation time and PT. SGA was significantly associated with T2 value (Z-score), f, and UmA-PI (Z-score). In the ECS groups, T2 value (Z-score), f, and Dfast were significantly lower than those in non-ECS groups. All IVIM parameters and T2 values (Z-score) showed significantly lower scores in the preterm birth group. CONCLUSION: Placental f and T2 value (Z-score) had significant associations with low birth weight and clinical adverse outcomes and could be potential imaging biomarkers of placental insufficiency.

Risk Stratification for Pregnancies Diagnosed With Fetal Growth Restriction Based on Placental MRI.

BACKGROUND: Diagnosis of fetal growth restriction (FGR) entails difficulties with differentiating fetuses not fulfilling their growth potential because of pathologic conditions, such as placental insufficiency, from constitutionally small fetuses. The feasibility of placental MRI for risk stratification among pregnancies diagnosed with FGR remains unexplored. PURPOSE: To explore quantitative MRI features useful to identify pregnancies with unfavorable outcomes and to assess the diagnostic performance of visual analysis of MRI to detect pregnancies with unfavorable outcomes, among pregnancies diagnosed with FGR. STUDY TYPE: Retrospective. POPULATION: Thirteen pregnancies with unfavorable outcomes (preterm emergency cesarean section or intrauterine fetal death) and 11 pregnancies with favorable outcomes performed MRI at gestational weeks 21-36. FIELD STRENGTH/SEQUENCE: A 5-T, half-Fourier-acquired single-shot turbo spin echo (HASTE), spin-echo echo-planar imaging (SE-EPI) and T2 map derived from SE-EPI. ASSESSMENT: Placental size on HASTE sequences and T2 mapping-based histogram features were extracted. Three radiologists qualitatively evaluated the visibility of maternal cotyledon on HASTE and SE-EPI sequences with echo times (TEs) = 60, 90, and 120 msec using 3-point Likert scales: 0, absent; 1, equivocal; and 2, present. STATISTICAL TESTS: Welch's t-test or Mann-Whitney U test for quantitative features between the favorable and unfavorable outcome groups. Areas under the receiver operating curves (AUCs) of the three readers' visual analyses to detect pregnancies with unfavorable outcomes. A P value of <0.05 was inferred as statistically significant. RESULTS: Placental size (major and minor axis, estimated area of placental bed, and volume of placenta) and T2 mapping-based histogram features (mean, skewness, and kurtosis) were statistically significantly different between the two groups. Visual analysis of HASTE and SE-EPI with TE = 60 msec showed AUCs of 0.80-0.86 to detect pregnancies with unfavorable outcomes. DATA CONCLUSION: Placental size, histogram features, and visual analysis of placental MRI may allow for risk stratification regarding outcomes among pregnancies diagnosed with FGR. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 5.

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.

Testing the Construct Validity and Responsiveness of the Single-Item Presenteeism Question.

OBJECTIVE: We tested the construct validity and responsiveness of a single-item instrument for measuring absolute presenteeism-the single-item presenteeism question (SPQ). METHODS: Two self-report questionnaire surveys were conducted among employees of 24 small- or medium-sized companies (N = 1021) concerning the recognized predictors of presenteeism-absenteeism, subjective health risks, work engagement, and workplace social capital. Responsiveness was measured by determining whether changes in the presence of predictors between the surveys were accompanied by commensurate changes in SPQ presenteeism. RESULTS: SPQ presenteeism exhibited significant associations with the predictors, denoting adequate construct validity. Regarding responsiveness, unfavorable changes in most predictors were associated with increased SPQ presenteeism, as expected. CONCLUSIONS: We confirmed the construct validity and responsiveness of the SPQ-an instrument that can be employed to promote workplace health and productivity management.

Diffusion-weighted imaging of uterine adenomyosis: Correlation with clinical backgrounds and comparison with malignant uterine tumors.

AIM: To elucidate correlation between signal intensity on diffusion-weighted images (SI-DWI) and clinical backgrounds for uterine adenomyosis and to compare SI-DWI of adenomyosis and malignant uterine tumors. METHODS: This study examined 46 adenomyosis patients diagnosed using magnetic resonance imaging and 25 patients with surgically confirmed malignant uterine myometrial tumor. First, adenomyosis cases were classified visually into high-intensity and low-intensity groups based on the SI-DWI compared with that of normal uterine myometrium. Secondly, correlation was assessed between SI-DWI of adenomyosis and patient clinical background information such as age, menopausal status, menstrual cycle and dysmenorrhea severity. Third, quantitative comparison was made of low-intensity adenomyosis (LIA), high-intensity adenomyosis (HIA) and malignant tumor groups for the signal intensity ratio (SIR) on DWI and the apparent diffusion coefficient (ADC). Their diagnostic performance was evaluated using logistic regression analysis and receiver operating characteristic (ROC) analysis. RESULTS: The 46 adenomyosis cases were classified as 26 low-intensity and 20 high-intensity cases. Significant correlation was found only for menstrual cycle phases. HIA had significantly lower SIR and higher ADC than malignant tumor. The ADC of HIA was significantly higher than that of LIA. The combination of SIR and ADC showed excellent diagnostic performance (area under ROC curve, 0.99). CONCLUSION: There is a variation in signal intensity on DWI of uterine adenomyosis and it is associated with menstrual cycle phase. Adenomyosis with high signal intensity on DWI can be differentiated from malignant lesions by its lower signal intensity on DWI and higher ADC than that found for malignant uterine tumors, however overlaps exist.

Microcystic, Elongated and Fragmented Pattern Invasion Can Adversely Influence Preoperative Staging for Low-grade Endometrial Carcinoma.

PURPOSE: To investigate the influence of microcystic, elongated and fragmented (MELF) pattern invasion on preoperative evaluation of lymph node (LN) metastasis and myometrial invasion in patients with low-grade endometrial carcinoma. METHODS: The study included 192 consecutive patients with low-grade endometrial carcinoma who underwent preoperative computed tomography (CT) and magnetic resonance imaging (MRI), followed by surgery. One hundred sixty one of 192 patients underwent LN dissection and were analyzed for LN metastasis. All patients were analyzed for myometrial invasion. Presence of enlarged LN was evaluated by using size criteria on CT. Depth of myometrial invasion was evaluated on MRI using T2-weighted imaging, diffusion-weighted imaging and contrast-enhanced T1-weighted imaging comprehensively. Sensitivity and specificity for LN metastasis and deep myometrial invasion were evaluated for MELF group and non-MELF group. The difference of sensitivity between two groups was compared using Chi-square and Fisher's exact test. RESULTS: MELF pattern invasion was identified in 43/192 patients (22%). LN metastases were observed in 18/39 patients in MELF group and 6/122 patients in non-MELF group for pelvic LN and 11/29 patients in MELF group and 4/57 patients in non-MELF group for para-aortic LN. Sensitivity for the detection of pelvic LN metastasis in MELF group was significantly lower than in non-MELF group (16.7% vs 66.7%). As for the assessment of the deep myometiral invasion, pathological deep myometrial invasion were found in 31/43 patients in MELF group and 32/149 patients in non-MELF group. Sensitivity in MELF group showed lower values than in non-MELF group (54.8% vs 78.1% for reader 1, 54.8% vs 62.5% for reader 2), although there was no statistically significant difference (P = 0.09 for reader 1 and P = 0.72 for reader 2). CONCLUSION: In case of low-grade endometrial carcinoma with MELF pattern invasion, preoperative staging by CT and MRI have a risk for underestimation.

Quantitative and Qualitative Evaluation of Convolutional Neural Networks with a Deeper U-Net for Sparse-View Computed Tomography Reconstruction.

RATIONALE AND OBJECTIVES: To evaluate the utility of a convolutional neural network (CNN) with an increased number of contracting and expanding paths of U-net for sparse-view CT reconstruction. MATERIALS AND METHODS: This study used 60 anonymized chest CT cases from a public database called "The Cancer Imaging Archive". Eight thousand images from 40 cases were used for training. Eight hundred and 80 images from another 20 cases were used for quantitative and qualitative evaluation, respectively. Sparse-view CT images subsampled by a factor of 20 were simulated, and two CNNs were trained to create denoised images from the sparse-view CT. A CNN based on U-net with residual learning with four contracting and expanding paths (the preceding CNN) was compared with another CNN with eight contracting and expanding paths (the proposed CNN) both quantitatively (peak signal to noise ratio, structural similarity index), and qualitatively (the scores given by two radiologists for anatomical visibility, artifact and noise, and overall image quality) using the Wilcoxon signed-rank test. Nodule and emphysema appearance were also evaluated qualitatively. RESULTS: The proposed CNN was significantly better than the preceding CNN both quantitatively and qualitatively (overall image quality interquartile range, 3.0-3.5 versus 1.0-1.0 reported from the preceding CNN; p < 0.001). However, only 2 of 22 cases used for emphysematous evaluation (2 CNNs for every 11 cases with emphysema) had an average score of ≥ 2 (on a 3 point scale). CONCLUSION: Increasing contracting and expanding paths may be useful for sparse-view CT reconstruction with CNN. However, poor reproducibility of emphysema appearance should also be noted.

Metabolic syndrome: Association between prevalence and risk at worksites.

This study, conducted at major Japanese companies, aimed to determine if asymptomatic workers in workplaces with a high prevalence of metabolic syndrome have a greater risk of developing metabolic syndrome. Data were obtained from the health records of 298,145 people, from 2011 to 2015. We collected data on the participants' age, sex, physical examinations, laboratory tests, and lifestyle behaviors. To test whether the risk of metabolic syndrome in asymptomatic workers differed between groups with a higher and lower prevalence in 2011, Cox proportional hazards regression model was performed, with the covariates being controlled for. The analysis showed that the risk of metabolic syndrome among asymptomatic workers in the high-prevalence group was about 1.1-fold elevated compared to those within the low-prevalence group. As a follow-up to these results, interventions aimed at asymptomatic workers should be provided in workplaces with a high prevalence of metabolic syndrome.

Novel subtype of atonic postpartum hemorrhage: dynamic computed tomography evaluation of bleeding characteristics and the uterine cavity.

Background: Uterine atony is the leading cause of severe postpartum hemorrhage (PPH); however, the underlying cause of intractable atonic PPH unresponsive to conventional treatments (such as uterotonics and intrauterine balloon tamponade) remains unclear.Objectives: The aim of this study was to investigate whether intractable atonic PPH is associated with the type of bleeding (arterial or nonarterial) and its location, along with variations in the size and shape of the uterine cavity after delivery.Study design: This retrospective study included women who had undergone a dynamic computed tomography (CT) scan for the management of severe PPH at Kyoto University Hospital between April 2011 and March 2017. Patients' electronic medical records were reviewed, and relevant clinical information was collected. The presence of contrast extravasation (CE) on CT images in the early phase (40 s) was regarded as active arterial bleeding. Bleeding sites and size of the uterine cavity were evaluated using an xyz coordinate system. The size of the uterine cavity was compared between groups with CE into the upper and lower parts of the uterine body.Results: Of the 60 women assessed for eligibility, 30 were included in the current analysis. Contrast extravasation was detected in 19 women, with 14 showing CE in the early phase. The presence of CE in the early phase was significantly associated with the need for transarterial embolization (Fisher's exact test, p = .0017). The upper and lower parts of the uterine cavity were 97.4 ± 2.7 mm (mean ± standard error of the mean) and 87.2 ± 3.5 mm in length, respectively. The maximum anteroposterior diameters of the upper and lower parts of the uterine cavity were 23.1 ± 2.6 and 76.0 ± 3.0 mm, respectively, and the largest transverse diameters were 67.3 ± 1.9 and 81.1 ± 2.3 mm, respectively. The group that showed CE into the upper uterine cavity had significantly larger qualitative parameters of the upper uterine cavity compared to the group with CE into the lower uterine cavity. The gate from the lower uterine cavity toward the upper uterine cavity was narrow (anteroposterior diameter of 22.6 ± 2.0 mm, transverse diameter of 40.7 ± 3.3 mm), and the intrauterine balloon was always found in the lower uterine cavity on the CT scan. The upper uterine body was characterized by a flat oval-shaped cavity (xy plane), thick uterine wall, and lack of uniformity among bleeding sites (z = 62.4 ± 14.8 mm). In contrast, the lower uterine cavity was a circular shape (xy plane) with thin walls, and bleeding sites were located at lateral sides around the level of the internal os (z = -18.8 ± 4.9 mm).Conclusions: Atonic PPH has a significant subtype, named "PRACE," which is characterized by PPH, resistance to treatment, and arterial CE. The need for embolization can be predicted by the presence of arterial bleeding and its location, along with the shape of the uterine cavity.

MR findings of uterine PEComa in patients with tuberous sclerosis: report of two cases.

Tuberous sclerosis complex (TSC), a rare autosomal dominant neurocutaneous disorder, is characterized by the presence of benign congenital tumors in multiple organs. Neoplasms with perivascular epithelioid cell differentiation (PEComas), including angiomyolipoma (AML) and lymphangioleiomyomatosis (LAM), can occur in association with TSC. This report describes two cases of uterine PEComas presenting characteristic MR imaging features reflecting pathological findings. From MR images, both cases showed single or multiple large, irregularly shaped or lobulated hemorrhagic lesions within the myometrium. They differed from typical adenomyotic cysts in their large size and irregular margins. Histopathologic analysis revealed that the hemorrhage was caused by adenomyosis and tumor cells that proliferated in surrounding stroma of the hemorrhagic lesions, compatible with PEComas. Microscopic observation revealed an infiltrative growth pattern of PEComas, with small nodules formed. The tumor lesions, however, were difficult to detect on MR images. The myometrium showed normal appearance on both T1-weighted and T2-weighted images in both cases. We speculate that PEComas may infiltrate extensively into the myometrium even when the myometrium shows almost normal radiologic appearance.

Longitudinal changes in magnetic resonance imaging of malignant and borderline tumors associated with ovarian endometriotic cyst comparing with endometriotic cysts without arising malignancy.

PURPOSE: To investigate magnetic resonance (MR) findings and to detect malignant transformation of ovarian endometriotic cysts by comparing longitudinal changes in patients with ovarian malignant/borderline tumors associated with ovarian endometriotic cysts (tumor group) with those of patients with endometriotic cysts (control group). METHODS: Tumor group patients (n = 10) had ovarian malignant/borderline tumors with pathologically confirmed association with endometriosis and available prior MRI of endometriotic cysts. Control group patients (n = 40) had been diagnosed more than two times as having ovarian endometriotic cysts by MRI examination. The tumor and solid portion sizes were measured. Two radiologists independently evaluated signal intensity (SI) of the cystic portion on both T1-weighted and T2-weighted images (WI), presence of shading on T2WI, and T2 dark spot sign in both groups and evaluate longitudinal changes of those findings. RESULTS: Pathological diagnoses of the tumor group were clear cell carcinoma (n = 6), endometrioid carcinoma (n = 1), serous carcinoma (n = 1), mucinous borderline tumor (n = 1), and endometrioid borderline tumor (n = 1). Tumor size had increased significantly in the tumor group (p = .004), but not in controls. Solid portions were identified in all cases only when neoplasms were suspected. Disappearance of shading during the follow-up period was observed more in tumor group (n = 2) than in the controls (n = 0). No significant difference was found between groups in the SI on T1 and T2WI, and T2 dark spot sign for the two MR examinations. CONCLUSIONS: The MR findings suggesting malignant transformation were emergence of a solid portion and increase in cyst size. Disappearance of shading also facilitates the follow-up of endometriotic cysts.

A Predictor of Tumor Recurrence in Patients With Endometrial Carcinoma After Complete Resection of the Tumor: The Role of Pretreatment Apparent Diffusion Coefficient.

OBJECTIVES: The aim of this study was to assess the prognostic and incremental value of pretreatment apparent diffusion coefficient (ADC) values of tumors for the prediction of tumor recurrence after complete resection of the tumor in patients with endometrial cancer. METHODS: This study enrolled 210 patients with stages IA to IIIC endometrial cancer who had undergone complete resection of the tumor and pretreatment magnetic resonance imaging. The minimum and mean ADC values (ADCmin, ADCmean) of tumors and normalized ADC (nADCmin, nADCmean) were calculated from magnetic resonance imaging. The primary outcome was recurrence-free survival (RFS). Receiver operating characteristic analysis was performed to compare the diagnostic performance of ADC values of 4 types. The Kaplan-Meier method, log-rank tests, and Cox regression were used to explore associations between recurrence and the ADC values with adjustment for clinicopathological factors. RESULTS: In receiver operating characteristic curve analysis, the areas under the curve were significant for ADCmean and nADCmean predicting tumor recurrence but were not significant for ADCmin and nADCmin. Regarding univariate analysis, ADCmean and nADCmean were significantly associated with increased risk of recurrence. Multivariate analysis showed that ADCmean and nADCmean remained independently associated with shorter RFS. In the high-risk group, the RFS of patients with lower ADC values (ADCmean and nADCmean) was significantly shorter than that of patients in the higher ADC value group. CONCLUSIONS: Pretreatment tumor ADCmean and nADCmean were important imaging biomarkers for predicting recurrence in patients after complete resection of the tumor. They might improve existing risk stratification.