Monoradiculopathy-induced abdominal pseudohernia caused by T11-12 soft disc herniation: a case report and literature review.

BACKGROUND: An abdominal pseudohernia is a rare clinical entity that consists of an abnormal bulging of the abdominal wall that can resemble a true hernia but does not have an associated underlying fascial or muscle defect. Abdominal pseudohernia is believed to result from denervation of the abdominal muscles in cases of herpes zoster infection, diabetes mellitus, lower thoracic or upper lumbar disc herniation, surgical injuries, and rib fracture. To date, nine cases of abdominal pseudohernia caused by disc herniation at the lower thoracic or upper lumbar levels have been reported. CASE PRESENTATION: A 35-year-old man with no underlying disease or traumatic event presented with chief complaints of left flank pain and a protruding left lower abdominal mass that had formed one day earlier. There was no true abdominal hernia on abdominal computed tomography (CT), although CT and magnetic resonance imaging (MRI) showed a herniated soft (non-calcified) disc into the left neural foramen at the T11-12 level. A nonsteroidal anti-inflammatory drug was prescribed for the flank pain, and the patient was followed on a regular basis for six months. Follow-up MRI taken at the last visit showed complete resorption of the herniated disc. Abdominal pseudohernia and flank pain were also completely resolved. CONCLUSION: We report a rare case of monoradiculopathy-induced abdominal pseudohernia caused by foraminal soft disc herniation at the T11-12 level. In patients who have an abdominal pseudohernia without herpes zoster infection, diabetes mellitus, or traumatic events, lower thoracic disc herniations should be included in differential diagnosis.

Effects of Fetal Images Produced in Virtual Reality on Maternal-Fetal Attachment: Randomized Controlled Trial.

BACKGROUND: Maternal-fetal attachment (MFA) has been reported to be associated with the postpartum mother-infant relationship. Seeing the fetus through ultrasound might influence MFA, and the effect could be increased by more realistic images, such as those generated in virtual reality (VR). OBJECTIVE: The aim was to determine the effect of fetal images generated in VR on MFA and depressive symptoms through a prenatal-coaching mobile app. METHODS: This 2-arm parallel randomized controlled trial involved a total of 80 pregnant women. Eligible women were randomly assigned to either a mobile app-only group (n=40) or an app plus VR group (n=40). The VR group experienced their own baby's images generated in VR based on images obtained from fetal ultrasonography. The prenatal-coaching mobile app recommended health behavior for the pregnant women according to gestational age, provided feedback on entered data for maternal weight, blood pressure, and glucose levels, and included a private diary service for fetal ultrasound images. Both groups received the same app, but the VR group also viewed fetal images produced in VR; these images were stored in the app. All participants filled out questionnaires to assess MFA, depressive symptoms, and other basic medical information. The questionnaires were filled out again after the interventions. RESULTS: Basic demographic data were comparable between the 2 groups. Most of the assessments showed comparable results for the 2 groups, but the mean score to assess interaction with the fetus was significantly higher for the VR group than the control group (0.4 vs 0.1, P=.004). The proportion of participants with an increased score for this category after the intervention was significantly higher in the VR group than the control group (43% vs 13%, P=.005). The feedback questionnaire revealed that scores for the degree of perception of fetal appearance all increased after the intervention in the VR group. CONCLUSIONS: The use of a mobile app with fetal images in VR significantly increased maternal interaction with the fetus. TRIAL REGISTRATION: ClinicalTrials.gov NCT04942197; https://clinicaltrials.gov/ct2/show/NCT04942197.

Is the Surface Anatomy of the Popliteal Crease Related to Lower Extremity Alignment or Knee Osseous Morphology? A Radiographic Study.

Background and objectives: The popliteal crease varies among individuals, and there has been no prior study on this aspect. We assumed that it may be associated with lower extremity alignment and osseous morphology. To demonstrate this, we conducted a radiographic analysis. Materials and Methods: The study was conducted on 121 knees of 63 patients, whose popliteal creases were well distinguished on clinical photographs. PCOA was defined as the angle between the longitudinal axis of the lower leg and the popliteal crease. Through the radiologic examinations performed, the HKA, MPTA, mLDFA, JLCA, MFCA/TEA, and PCA/TEA were measured. Pearson correlation analysis and multiple linear regression analysis were performed on the PCOA and the six radiologic measurements to analyze the relationship. Results: Pearson correlation analysis found HKA had the highest coefficient at 0.568. In multiple linear regression, only HKA was associated, excluding all other measurements. Conclusions: Popliteal crease obliquity is significantly associated with coronal plane lower extremity alignment and exhibits a stronger correlation than with underlying knee osseous morphology. If future research is conducted based on this, popliteal crease could serve as a valuable clue for predicting lower extremity alignment and the risk of osteoarthritis development.

Association between cesarean section rate and maternal age in twin pregnancies.

OBJECTIVES: To evaluate the effect of maternal age to the cesarean section rate of twin pregnancies in late preterm and term gestation. METHODS: A retrospective study was performed on twin pregnancies delivered at Seoul National University Bundang Hospital from June 2003 to December 2020. Preterm births before 34 weeks of gestation were excluded, and only live births were analyzed. The patients were classified into four groups according to maternal age (<30, 30-34, 35-39, and ≥40 years). The primary outcome was the rate of cesarean section. RESULTS: The median value of maternal body mass index, the rate of assisted reproductive technology, dichorionic twin pregnancy, preeclampsia, and gestational diabetes increased significantly according to the maternal age group (all p<0.05). Among a total of 2,075 twin pregnancies, the rates of cesarean section were 65, 74, 80, and 95% for groups with maternal age under 30, 30-34, 35-39, and ≥40 years, respectively (p<0.001). The cesarean section rates after a trial of labor were 22, 22, 28, and 63%, respectively (p=0.032). Maternal old age was an independent risk factor for cesarean section after a trial of labor in both nulliparous and multiparous women after adjusting for confounding factors. CONCLUSIONS: The rate of cesarean section in twin pregnancies significantly increased as maternal age increased, even in multiparous women.

Cartilage Regeneration Using Human Umbilical Cord Blood Derived Mesenchymal Stem Cells: A Systematic Review and Meta-Analysis.

Background and Objectives: Human umbilical-cord-blood-derived mesenchymal stem cells (hUCB-MSCs) have recently been used in clinical cartilage regeneration procedures with the expectation of improved regeneration capacity. However, the number of studies using hUCB-MSCs is still insufficient, and long-term follow-up results after use are insufficient, indicating the need for additional data and research. We have attempted to prove the efficacy and safety of hUCB-MSC treatment in a comprehensive analysis by including all subjects with knee articular cartilage defect or osteoarthritis who have undergone cartilage repair surgery using hUCB-MSCs. We conducted a meta-analysis and demonstrated efficacy and safety based on a systematic review. Materials and Methods: This systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. For this study, we searched the PubMed, Embase, Web of Science, Scopus, and Cochrane Library literature databases up to June 2022. A total of seven studies were included, and quality assessment was performed for each included study using the Newcastle−Ottawa Quality Assessment Scale. Statistical analysis was performed on the extracted pooled clinical outcome data, and subgroup analyses were completed. Results: A total of 570 patients were included in the analysis. In pooled analysis, the final follow-up International Knee Documentation Committee (IKDC) score showed a significant increase (mean difference (MD), −32.82; 95% confidence interval (CI), −38.32 to −27.32; p < 0.00001) with significant heterogeneity (I2 = 93%, p < 0.00001) compared to the preoperative score. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores at final follow-up were significantly decreased (MD, 30.73; 95% CI, 24.10−37.36; p < 0.00001) compared to the preoperative scores, with significant heterogeneity (I2 = 95%, p < 0.00001). The visual analog scale (VAS) score at final follow-up was significantly decreased (MD, 4.81; 95% CI, 3.17−6.46; p < 0.00001) compared to the preoperative score, with significant heterogeneity (I2 = 98%, p < 0.00001). Two studies evaluated the modified Magnetic Resonance Observation of Cartilage Repair Tissue (M-MOCART) score and confirmed sufficient improvement. In a study analyzing a group treated with bone marrow aspiration concentrate (BMAC), there was no significant difference in clinical outcome or M-MOCART score, and the post-treatment International Cartilage Repair Society (ICRS) grade increased. Conclusion: This analysis demonstrated the safety, efficacy, and quality of repaired cartilage following hUCB-MSC therapy. However, there was no clear difference in the comparison with BMAC. In the future, comparative studies with other stem cell therapies or cartilage repair procedures should be published to support the superior effect of hUCB-MSC therapy to improve treatment of cartilage defect or osteoarthritis.

Benign Breast Papilloma without Atypia: Outcomes of Surgical Excision versus US-guided Directional Vacuum-assisted Removal or US Follow-up.

Background Recent studies suggest that US-guided directional vacuum-assisted removal (DVAR) is a satisfactory alternative to surgery for benign papilloma of the breast and recommend discretionary diagnostic US follow-up without intervention. Purpose To compare the outcomes of benign papilloma without atypia diagnosed with core needle biopsy (CNB) in patients who underwent US-guided DVAR, US follow-up without intervention, or surgery. Materials and Methods This retrospective review included consecutive patients with benign papilloma without atypia diagnosed with US-guided CNB between January 2005 and September 2015. Five hundred female patients who underwent surgical excision (n = 206), US-guided DVAR (n = 233), or more than 2 years of US follow-up without intervention (n = 61) were included. The clinical and radiologic findings and cancer upgrade rate were compared among the three groups. Propensity score matching was performed for comparison of the upgrade rate in the surgery and US-guided DVAR groups. Results The mean patient age (±standard deviation) was 46.4 years ± 9.6. The upgrade rate to malignancy was 1.8% (nine of 500 patients; 95% confidence interval [CI]: 0.9%, 3.4%) in the total study population, 1.9% (four of 206 patients; 95% CI: 0.8%, 4.9%) after surgery, 2.1% (five of 233 patients; 95% CI: 0.9%, 4.9%) after US-guided DVAR, and 0% (0 of 61 patients; 95% CI: 0.0%, 5.9%) after US follow-up without intervention (P = .80); after propensity-score matching, the upgrade rate was 1.9% in the surgery group (three of 151 patients; 95% CI: 0.6%, 5.6%) and 3.3% in the US-guided DVAR group (five of 151 patients; 95% CI: 1.4%, 7.5%; P = .48). The recurrence rate after US-guided DVAR was 3.6% (six of 166 patients) during 24-65 months of follow-up; all recurrences were confirmed as benign at subsequent surgery. Fifty-nine of the 61 lesions in the group with US follow-up without intervention (97%) remained stable in size with no growth during a mean follow-up of 43.3 months (range, 25-130 months). Conclusion Low rates of upgrade, recurrence, and growth after US-guided directional vacuum-assisted removal and US follow-up without intervention suggest that benign papilloma without atypia can be managed more conservatively rather than undergoing surgical excision. © RSNA, 2019 Online supplemental material is available for this article.

Predictors of Invasive Breast Cancer in Patients With Ductal Carcinoma In Situ in Ultrasound-Guided Core Needle Biopsy.

OBJECTIVES: To determine predictors of invasiveness of lesions with US-guided biopsy-confirmed ductal carcinoma in situ (DCIS), focusing on US features, including shear wave elastography (SWE). METHODS: From January 2015 to September 2016, a total of 80 lesions with US-guided biopsy-confirmed DCIS were detected in patients who underwent preoperative mammography, B-mode US, and SWE. Data were retrospectively reviewed from clinical records, pathologic reports, and imaging assessments. Imaging data included mammographic findings, B-mode US findings based on the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS), and the mean and maximum elasticity values on SWE. The final BI-RADS assessment, including the degree of elasticity of the mass, was evaluated. Continuous variables were examined by an independent t test, and categorical variables were examined by the Fisher exact test. The independent factors for predicting a histologic upgrade were evaluated by a multivariate logistic regression analysis. RESULTS: Among the 80 lesions, 27 (33.8%) showed an invasive component after surgical excision. None of the BI-RADS US descriptors, which include shape, orientation, margin, and echogenicity, showed a significant correlation with the rate of a histologic upgrade to invasive cancer. However, the BI-RADS assessment category (P = .015) and nuclear grade (P = .005) were significantly correlated with invasiveness of the mass. The maximum stiffness value was lower in the pure DCIS group (119.04 vs 85.33 kPa; P = .041). CONCLUSIONS: The BI-RADS category based on US findings, maximum stiffness value on SWE, and nuclear grade of DCIS are predictive of invasive components in DCIS.

miRTarVis+: Web-based interactive visual analytics tool for microRNA target predictions.

In this paper, we present miRTarVis+, a Web-based interactive visual analytics tool for miRNA target predictions and integrative analyses of multiple prediction results. Various microRNA (miRNA) target prediction algorithms have been developed to improve sequence-based miRNA target prediction by exploiting miRNA-mRNA expression profile data. There are also a few analytics tools to help researchers predict targets of miRNAs. However, there still is a need for improving the performance for miRNA prediction algorithms and more importantly for interactive visualization tools for an integrative analysis of multiple prediction results. miRTarVis+ has an intuitive interface to support the analysis pipeline of load, filter, predict, and visualize. It can predict targets of miRNA by adopting Bayesian inference and maximal information-based nonparametric exploration (MINE) analyses as well as conventional correlation and mutual information analyses. miRTarVis+ supports an integrative analysis of multiple prediction results by providing an overview of multiple prediction results and then allowing users to examine a selected miRNA-mRNA network in an interactive treemap and node-link diagram. To evaluate the effectiveness of miRTarVis+, we conducted two case studies using miRNA-mRNA expression profile data of asthma and breast cancer patients and demonstrated that miRTarVis+ helps users more comprehensively analyze targets of miRNA from miRNA-mRNA expression profile data. miRTarVis+ is available at http://hcil.snu.ac.kr/research/mirtarvisplus.

Development of an algorithm to automatically compress a CT image to visually lossless threshold.

BACKGROUND: To develop an algorithm to predict the visually lossless thresholds (VLTs) of CT images solely using the original images by exploiting the image features and DICOM header information for JPEG2000 compression and to evaluate the algorithm in comparison with pre-existing image fidelity metrics. METHODS: Five radiologists independently determined the VLT for 206 body CT images for JPEG2000 compression using QUEST procedure. The images were divided into training (n = 103) and testing (n = 103) sets. Using the training set, a multiple linear regression (MLR) model was constructed regarding the image features and DICOM header information as independent variables and regarding the VLTs determined with median value of the radiologists' responses (VLTrad) as dependent variable, after determining an optimal subset of independent variables by backward stepwise selection in a cross-validation scheme. The performance was evaluated on the testing set by measuring absolute differences and intra-class correlation (ICC) coefficient between the VLTrad and the VLTs predicted by the model (VLTmodel). The performance of the model was also compared two metrics, peak signal-to-noise ratio (PSNR) and high-dynamic range visual difference predictor (HDRVDP). The time for computing VLTs between MLR model, PSNR, and HDRVDP were compared using the repeated ANOVA with a post-hoc analysis. P < 0.05 was considered to indicate a statistically significant difference. RESULTS: The means of absolute differences with the VLTrad were 0.58 (95% CI, 0.48, 0.67), 0.73 (0.61, 0.85), and 0.68 (0.58, 0.79), for the MLR model, PSNR, and HDRVDP, respectively, showing significant difference between them (p < 0.01). The ICC coefficients of MLR model, PSNR, and HDRVDP were 0.88 (95% CI, 0.81, 0.95), 0.85 (0.79, 0.91), and 0.84 (0.77, 0.91). The computing times for calculating VLT per image were 1.5 ± 0.1 s, 3.9 ± 0.3 s, and 68.2 ± 1.4 s, for MLR metric, PSNR, and HDRVDP, respectively. CONCLUSIONS: The proposed MLR model directly predicting the VLT of a given CT image showed competitive performance to those of image fidelity metrics with less computational expenses. The model would be promising to be used for adaptive compression of CT images.

Diagnostic performance of smartphone reading of the coronary CT angiography in patients with acute chest pain at ED.

PURPOSE: The aims of this study were to simulate mobile consultation for the coronary computed tomography angiography (CCTA) at the emergency department (ED) and to measure the diagnostic performance of the mobile reading. MATERIALS AND METHODS: A total of 107 patients with acute chest pain who underwent CCTA and coronary angiography (CAG) were included. The CCTA images were reviewed by a cardiac radiologist using a smartphone. The degree of stenosis at each coronary segment was scored with 4-point scale (score 1, <50%; score 2, 51%-70%; score 3, 71%-90%; score 4, >90%). The degree of stenosis at each coronary segments were also scored with preliminary CCTA report by on-call residents, final CCTA reports by in-house attending cardiac radiologists, and CAG. Interobserver agreement was measured using κ statistics. The areas under the receiver operating characteristic curves (AUCs) for diagnosing segments with obstructive stenosis were compared between each reader and CAG. RESULTS: The smartphone reader's reading was more similar to the CAG results and in-house radiologists' reports than reading of on-call residents. The diagnostic performance of smartphone reading for detection of obstructive stenosis was significantly greater than that of on-call residents (AUC, 0.89 vs 0.75; P<.001) and did not significantly differ from that of the in-house radiologists (AUC, 0.89 vs 0.90; P=.05). CONCLUSION: Smartphone reading by the cardiac radiologist was superior to the on-call residents' reading. Further study with real-time mobile consultation needs to be investigated to evaluate whether improvement in diagnostic competency can make a difference in the outcome of patients.

XCluSim: a visual analytics tool for interactively comparing multiple clustering results of bioinformatics data.

BACKGROUND: Though cluster analysis has become a routine analytic task for bioinformatics research, it is still arduous for researchers to assess the quality of a clustering result. To select the best clustering method and its parameters for a dataset, researchers have to run multiple clustering algorithms and compare them. However, such a comparison task with multiple clustering results is cognitively demanding and laborious. RESULTS: In this paper, we present XCluSim, a visual analytics tool that enables users to interactively compare multiple clustering results based on the Visual Information Seeking Mantra. We build a taxonomy for categorizing existing techniques of clustering results visualization in terms of the Gestalt principles of grouping. Using the taxonomy, we choose the most appropriate interactive visualizations for presenting individual clustering results from different types of clustering algorithms. The efficacy of XCluSim is shown through case studies with a bioinformatician. CONCLUSIONS: Compared to other relevant tools, XCluSim enables users to compare multiple clustering results in a more scalable manner. Moreover, XCluSim supports diverse clustering algorithms and dedicated visualizations and interactions for different types of clustering results, allowing more effective exploration of details on demand. Through case studies with a bioinformatics researcher, we received positive feedback on the functionalities of XCluSim, including its ability to help identify stably clustered items across multiple clustering results.

Initial Performance of Radiologists and Radiology Residents in Interpreting Low-Dose (2-mSv) Appendiceal CT.

OBJECTIVE: The objective of our study was to prospectively evaluate the initial diagnostic performance and learning curve of a community of radiologists and residents in interpreting 2-mSv appendiceal CT. SUBJECTS AND METHODS: We included 46 attending radiologists and 153 radiology residents from 22 hospitals who completed an online training course of 30 2-mSv CT cases. Appendicitis was confirmed in 14 cases. Most of the readers had limited (≤ 10 cases, n = 32) or no (n = 118) prior experience with low-dose appendiceal CT. The order of cases was randomized for each reader. A multireader multicase ROC analysis was performed. Generalized estimating equations were used to model the learning curves in diagnostic performance. RESULTS: Diagnostic performance gradually improved with years of training. The average AUC was 0.94 (95% CI, 0.90-0.98), 0.92 (0.88-0.96), 0.90 (0.85-0.96), and 0.86 (0.80-0.92) for the attending radiologists, senior residents, 2nd-year residents, and 1st-year residents, respectively. We did not observe any notable intrareader learning curves over the training course of the 30 cases except a decrease in reading time. Diagnostic accuracy and sensitivity were significantly affected by the reader training level and prior overall experience with appendiceal CT but not by the prior specific experience with low-dose appendiceal CT. CONCLUSION: The learning curve is likely prolonged and forms gradually over years by overall radiology training and clinical experience in general rather than by experience with low-dose appendiceal CT specifically.

Low-Dose (2-mSv) CT in Adolescents and Young Adults With Suspected Appendicitis: Advantages of Additional Review of Thin Sections Using Multiplanar Sliding-Slab Averaging Technique.

OBJECTIVE: The purpose of this study is to assess the advantages of additional multiplanar sliding-slab averaging review of 2-mm-thick (thin) sections over stack review of 5-mm-thick (thick) sections in difficult cases of 2-mSv CT in adolescents and young adults with suspected appendicitis. MATERIALS AND METHODS: We included 149 patients (mean age, 28.0 years; 61 male patients and 88 female patients) for whom the initial CT reports were inconclusive for the diagnosis of appendicitis. Five independent radiologists retrospectively reviewed the thick sections in the stack mode and then the thin sections using sliding-slab averaging. In each review, they rated the likelihood of appendicitis and the appendix visualization using 5- and 3-point Likert scales, respectively. Diagnostic performance and confidence were compared between the two reviews using ROC analysis, McNemar tests, and Wilcoxon signed-rank tests. RESULTS: The pooled AUCs were 0.90 and 0.93 for the stack and sliding-slab averaging reviews, respectively (90% CI for the difference, 0.002-0.06; p = 0.087). For the individual readers, the sliding-slab averaging review tended to increase the AUC (range, 0.86-0.93 for stack vs 0.87-0.97 for sliding-slab averaging review), improve the confidence in diagnosing (mean score, 3.6-4.7 vs 3.9-4.7) or ruling out (1.6-2.1 vs 1.5-1.9) appendicitis, reduce indeterminate interpretations (0-15% vs 0-11%), and enhance the normal appendix visualization (1.1-1.7 vs 1.1-1.9), although the differences were not always statistically significant. CONCLUSION: Sliding-slab averaging review of thin sections is helpful when the diagnosis of appendicitis is difficult at 2-mSv CT in adolescents and young adults.

Feasibility of semiautomated MR volumetry using gadoxetic acid-enhanced MRI at hepatobiliary phase for living liver donors.

PURPOSE: To assess the feasibility of semiautomated MR volumetry using gadoxetic acid-enhanced MRI at the hepatobiliary phase compared with manual CT volumetry. METHODS: Forty potential live liver donor candidates who underwent MR and CT on the same day, were included in our study. Semiautomated MR volumetry was performed using gadoxetic acid-enhanced MRI at the hepatobiliary phase. We performed the quadratic MR image division for correction of the bias field inhomogeneity. With manual CT volumetry as the reference standard, we calculated the average volume measurement error of the semiautomated MR volumetry. We also calculated the mean of the number and time of the manual editing, edited volume, and total processing time. RESULTS: The average volume measurement errors of the semiautomated MR volumetry were 2.35% ± 1.22%. The average values of the numbers of editing, operation times of manual editing, edited volumes, and total processing time for the semiautomated MR volumetry were 1.9 ± 0.6, 8.1 ± 2.7 s, 12.4 ± 8.8 mL, and 11.7 ± 2.9 s, respectively. CONCLUSION: Semiautomated liver MR volumetry using hepatobiliary phase gadoxetic acid-enhanced MRI with the quadratic MR image division is a reliable, easy, and fast tool to measure liver volume in potential living liver donors.

Off-site smartphone reading of CT images for patients with inconclusive diagnoses of appendicitis from on-call radiologists.

OBJECTIVE: The purpose of this study was to simulate a mobile consultation in patients with inconclusive diagnosis of appendicitis made by on-call radiologists, as well as to measure the diagnostic confidence and performance of the mobile consultation. MATERIALS AND METHODS: Two off-site abdominal radiologists interpreted the CT images from 68 patients (including 29 patients with confirmed appendicitis) on a smart-phone for whom the preliminary CT reports by 25 in-house on-call radiologists were inconclusive. The smartphone readings were compared with the preliminary reports by on-call radiologists and with the original final reports by in-house abdominal radiologists. Heat maps, kappa statistics, Wilcoxon signed-rank tests, and ROC curves were used for data analysis. RESULTS: The heat maps and kappa statistics showed that the smartphone readings were more similar to the final reports than to the preliminary reports. In diagnosing or ruling out appendicitis, the smartphone readings were more confident than the preliminary reports (p ≤ 0.01) and did not significantly differ in diagnostic confidence from the final reports (p ≥ 0.19). The AUCs of the smartphone readings (0.91 and 0.92) did not differ significantly from those of the preliminary (0.85) or final (0.97) reports (p ≥ 0.09). CONCLUSION: With the given study sample, the diagnostic performance of the off-site smartphone readings did not differ significantly from that of the in-house preliminary reports. However, the smartphone readings provided higher diagnostic confidence than the preliminary reports.

Automated Versus Handheld Breast Ultrasound for Evaluating Axillary Lymph Nodes in Patients With Breast Cancer.

OBJECTIVE: Automated breast ultrasound (ABUS) is a relevant imaging technique for early breast cancer diagnosis and is increasingly being used as a supplementary tool for mammography. This study compared the performance of ABUS and handheld ultrasound (HHUS) in detecting and characterizing the axillary lymph nodes (LNs) in patients with breast cancer. MATERIALS AND METHODS: We retrospectively reviewed the medical records of women with recently diagnosed early breast cancer (≤ T2) who underwent both ABUS and HHUS examinations for axilla (September 2017-May 2018). ABUS and HHUS findings were compared using pathological outcomes as reference standards. Diagnostic performance in predicting any axillary LN metastasis and heavy nodal-burden metastases (i.e., ≥ 3 LNs) was evaluated. The ABUS-HHUS agreement for visibility and US findings was calculated. RESULTS: The study included 377 women (53.1 ± 11.1 years). Among 385 breast cancers in 377 patients, 101 had axillary LN metastases and 30 had heavy nodal burden metastases. ABUS identified benign-looking or suspicious axillary LNs (average, 1.4 ± 0.8) in 246 axillae (63.9%, 246/385). According to the per-breast analysis, the sensitivity, specificity, positive and negative predictive values, and accuracy of ABUS in predicting axillary LN metastases were 43.6% (44/101), 95.1% (270/284), 75.9% (44/58), 82.6% (270/327), and 81.6% (314/385), respectively. The corresponding results for HHUS were 41.6% (42/101), 95.1% (270/284), 75.0% (42/56), 82.1% (270/329), and 81.0% (312/385), respectively, which were not significantly different from those of ABUS (P ≥ 0.53). The performance results for heavy nodal-burden metastases were 70.0% (21/30), 89.6% (318/355), 36.2% (21/58), 97.3% (318/327), and 88.1% (339/385), respectively, for ABUS and 66.7% (20/30), 89.9% (319/355), 35.7% (20/56), 97.0% (319/329), and 88.1% (339/385), respectively, for HHUS, also not showing significant difference (P ≥ 0.57). The ABUS-HHUS agreement was 95.9% (236/246; Cohen's kappa = 0.883). CONCLUSION: Although ABUS showed limited sensitivity in diagnosing axillary LN metastasis in early breast cancer, it was still useful as the performance was comparable to that of HHUS.

Pregnancy outcomes of cerclage in twin gestations: a multicenter retrospective cohort study.

OBJECTIVES: To determine the effects of cerclage on twin pregnancies. METHODS: A multicenter, retrospective, cohort study was conducted at 10 tertiary centers using a web-based data collection platform. The study population included twin pregnancies delivered after 20 weeks of gestation. Patients with one or two fetal deaths before 20 weeks of gestation were excluded. Maternal characteristics, including prenatal cervical length (CL) and obstetric outcomes, were retrieved from the electronic medical records. RESULTS: A total of 1,473 patients had available data regarding the CL measured before 24 weeks of gestation. Seven patients without CL data obtained prior to cerclage were excluded from the analysis. The study population was divided into two groups according to the CL measured during the mid-trimester: the CL ≤2.5 cm group (n = 127) and the CL >2.5 cm group (n = 1,339). A total of 127 patients (8.7%) were included in the CL ≤2.5 cm group, including 41.7% (53/127) who received cerclage. Patients in the CL >2.5 cm group who received cerclage had significantly lower gestational age at delivery than the control group (hazard ratio (HR): 1.8; 95% confidence interval (CI): 1.11-2.87; p = .016). Patients in the CL ≤2.5 cm group who received cerclage had a significantly higher gestational age at delivery than the control group (HR: 0.5; 95% CI: 0.30-0.82; p value = .006). CONCLUSIONS: In twin pregnancies with a CL ≤2.5 cm, cerclage significantly prolongs gestation. However, unnecessary cerclage in women with a CL >2.5 cm may result in a higher risk of preterm labor and histologic chorioamnionitis although this study has a limitation originated from retrospective design.

Use of image features in predicting visually lossless thresholds of JPEG2000 compressed body CT images: initial trial.

PURPOSE: To test the image features that may be useful in predicting the visually lossless thresholds (VLTs) of body computed tomographic (CT) images for Joint Photographic Experts Group 2000 (JPEG2000) compression. MATERIALS AND METHODS: The institutional review board approved this study, with a waiver of informed patient consent. One hundred body CT studies obtained in different patients by using five scanning protocols were obtained, and 100 images, each of which was selected from each of the 100 studies, were collected. Five radiologists independently determined the VLT of each image for JPEG2000 compression by using the QUEST algorithm. The 100 images were randomly divided into two data sets-the training set (50 images) and the testing set (50 images)-and the division was repeated 200 times. For each of the 200 divisions, a multiple linear regression model was constructed on a training set and tested on a testing set regarding each of five image features-standard deviation of image intensity, image entropy, relative percentage of low-frequency (LF) energy, variation in high-frequency (HF) energy, and visual complexity-as independent variables and considering the VLTs determined with the median value of the radiologists' responses as a dependent variable. The root mean square residual and intraclass correlation coefficient (ICC) for the 200 divisions between the VLTs predicted by the models and those determined by radiologists were compared between the models by using repeated-measures analysis of variance with post-hoc comparisons. RESULTS: Mean root-mean-square residuals for multiple linear regression models constructed with variation in HF energy (1.20 ± 0.10 [standard deviation]) and visual complexity (1.09 ± 0.07) were significantly lower than those for standard deviation of image intensity (1.65 ± 0.13), image entropy (1.63 ± 0.14), and relative percentage of LF energy (1.58 ± 0.12) (P < .01). ICCs for variation in HF energy (0.64 ± 0.05) and visual complexity (0.71 ± 0.04) were significantly higher than those for standard deviation of image intensity (0.04 ± 0.02), image entropy (0.05 ± 0.02), and relative percentage of LF energy (0.20 ± 0.04) (P < .01). CONCLUSION: Among the five tested image features, variation in HF energy and visual complexity were the most promising in predicting the VLTs of body CT images for JPEG2000 compression.

Automatic registration of dental CT and 3D scanned model using deep split jaw and surface curvature.

BACKGROUND AND OBJECTIVES: In the medical field, various image registration applications have been studied. In dentistry, the registration of computed tomography (CT) volume data and 3D optically scanned models is essential for various clinical applications, including orthognathic surgery, implant surgical planning, and augmented reality. Our purpose was to present a fully automatic registration method of dental CT data and 3D scanned models. METHODS: We use a 2D convolutional neural network to regress a curve splitting the maxilla (i.e., upper jaw) and mandible (i.e., lower jaw) and the points specifying the front and back ends of the crown from the CT data. Using this regressed information, we extract the point cloud and vertices corresponding to the tooth crown from the CT and scanned data, respectively. We introduce a novel metric, called curvature variance of neighbor (CVN), to discriminate between highly fluctuating and smoothly varying regions of the tooth crown. The registration based on CVN enables more accurate fine registration while reducing the effects of metal artifacts. Moreover, the proposed method does not require any preprocessing such as extracting the iso-surface for the tooth crown from the CT data, thereby significantly reducing the computation time. RESULTS: We evaluated the proposed method with the comparison to several promising registration techniques. Our experimental results using three datasets demonstrated that the proposed method exhibited higher registration accuracy (i.e., 2.85, 1.92, and 7.73 times smaller distance errors for individual datasets) and smaller computation time (i.e., 4.12 times faster registration) than one of the state-of-the-art methods. Moreover, the proposed method worked considerably well for partially scanned data, whereas other methods suffered from the unbalancing of information between the CT and scanned data. CONCLUSIONS: The proposed method was able to perform fully automatic and highly accurate registration of dental CT data and 3D scanned models, even with severe metal artifacts. In addition, it could achieve fast registration because it did not require any preprocessing for iso-surface reconstruction from the CT data.

Usage trends of colorectal endoscopic submucosal dissection according to hospital types based on nationwide claims data.

Although the use of colorectal endoscopic submucosal dissection (ESD) for colorectal lesions has increased, there is a lack of analysis of the recent usage trends of ESD. Thus, this study aimed to identify changes in the annual utilization of ESD and determine the proportion of surgeries after ESD according to hospital types. Using Health Insurance Review and Assessment data from 2012 to 2019, 26,502 colorectal ESD cases were analyzed to assess the annual usage trends of ESD according to hospital type, additional early and late surgeries after ESD, changes in the distribution of colorectal lesions, and factors associated with early and late surgery. Trend analysis was performed using the chi-squared test for trend in proportions. Colorectal ESD increased from 2046 in 2012 to 5319 in 2019. Additional early and late surgeries rose from 135 (6.6%) in 2012 to 441 (8.2%) in 2019 (P < .05) and from 9 (0.3%) in 2013 to 52 (1.0%) in 2019 (P < .05), respectively. In tertiary and general hospitals, the proportion of submucosal cancers decreased, whereas the proportion of intramucosal cancers increased. Submucosal cancer was associated with early (odds ratio: 108.90, 95% confidence interval: 61.67-192.35) and late surgery (odds ratio: 3.55, 95% confidence interval: 2.27-5.56). Using nationwide data, our study identified the clinical usage trends of colorectal ESD based on the annual increase in utilization and the proportion of additional surgeries after ESD.