Added value of deep learning-based computer-aided diagnosis and shear wave elastography to b-mode ultrasound for evaluation of breast masses detected by screening ultrasound

Low specificity and operator dependency are the main problems of breast ultrasound (US) screening. We investigated the added value of deep learning-based computer-aided diagnosis (S-Detect) and shear wave elastography (SWE) to B-mode US for evaluation of breast masses detected by screening US.Between February 2018 and June 2019, B-mode US, S-Detect, and SWE were prospectively obtained for 156 screening US-detected breast masses in 146 women before undergoing US-guided biopsy. S-Detect was applied for the representative B-mode US image, and quantitative elasticity was measured for SWE. Breast Imaging Reporting and Data System final assessment category was assigned for the datasets of B-mode US alone, B-mode US plus S-Detect, and B-mode US plus SWE by 3 radiologists with varied experience in breast imaging. Area under the receiver operator characteristics curve (AUC), sensitivity, and specificity for the 3 datasets were compared using Delong''s method and McNemar test.Of 156 masses, 10 (6%) were malignant and 146 (94%) were benign. Compared to B-mode US alone, the addition of S-Detect increased the specificity from 8%–9% to 31%–71% and the AUC from 0.541–0.545 to 0.658–0.803 in all radiologists (All P < .001). The addition of SWE to B-mode US also increased the specificity from 8%–9% to 41%–75% and the AUC from 0.541–0.545 to 0.709–0.823 in all radiologists (All P < .001). There was no significant loss in sensitivity when either S-Detect or SWE were added to B-mode US.Adding S-Detect or SWE to B-mode US improved the specificity and AUC without loss of sensitivity.     

Shear wave elastography of the scalene muscles in healthy adults: A preliminary study

The aim of the study is to evaluate the reliability of shear wave elastography to assess the anterior and middle scalene muscles in healthy adult subjects.The study included 60 scalene muscles in 15 healthy subjects. High-resolution ultrasound and shear wave elastography were used to evaluate the anterior scalene and the middle scalene muscles. Stiffness values were measured.The mean shear elastic modulus showed the following values, right anterior scalene muscle 18.83 ± 5.32 kPa, left anterior scalene muscle 21.71 ± 4.8 kPa, right middle scalene muscle 12.84 ± 5.2 kPa, left middle scalene muscle 19.76 ± 5.30 kPa. Positive correlation was noted between the left middle scalene muscle and body mass index (P = .004). No difference in elasticity was noted between the right and left anterior scalene muscles; however, significant difference was noted between the right and left middle scalene muscles (P = .002).The results obtained in our study could be a reference point for future research considering different scalene muscle pathologies.     

Reproducibility of 3D free-breathing magnetic resonance coronary vessel wall imaging.

AIMS: Although the coronary artery vessel wall can be imaged non-invasively using magnetic resonance imaging (MRI), the in vivo reproducibility of wall thickness measures has not been previously investigated. Using a refined magnetization preparation scheme, we sought to assess the reproducibility of three-dimensional (3D) free-breathing black-blood coronary MRI in vivo. METHODS AND RESULTS: MRI vessel wall scans parallel to the right coronary artery (RCA) were obtained in 18 healthy individuals (age range 25-43, six women), with no known history of coronary artery disease, using a 3D dual-inversion navigator-gated black-blood spiral imaging sequence. Vessel wall scans were repeated 1 month later in eight subjects. The visible vessel wall segment and the wall thickness were quantitatively assessed using a semi-automatic tool and the intra-observer, inter-observer, and inter-scan reproducibilities were determined. The average imaged length of the RCA vessel wall was 44.5+/-7 mm. The average wall thickness was 1.6+/-0.2 mm. There was a highly significant intra-observer (r=0.97), inter-observer (r=0.94), and inter-scan (r=0.90) correlation for wall thickness (all P<0.001). There was also a significant agreement for intra-observer, inter-observer, and inter-scan measurements on Bland-Altman analysis. The intra-class correlation coefficients for intra-observer (r=0.97), inter-observer (r=0.92), and inter-scan (r=0.86) analyses were also excellent. CONCLUSION: The use of black-blood free-breathing 3D MRI in conjunction with semi-automated analysis software allows for reproducible measurements of right coronary arterial vessel-wall thickness. This technique may be well-suited for non-invasive longitudinal studies of coronary atherosclerosis.     

Value of shear wave elastography combined with the Toronto clinical scoring system in diagnosis of diabetic peripheral neuropathy

To evaluate the diagnostic values of shear wave elastography (SWE) alone and in combination with the Toronto clinical scoring system (TCSS) on diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes mellitus (T2DM).The study included 41 DPN patients, 42 non-DPN patients, and 21 healthy volunteers. Conventional ultrasonography and SWE were performed on the 2 sides of the tibial nerves, and cross-sectional area (CSA) and nerve stiffness were measured. TCSS was applied to all patients. A receiver operating characteristic curve analysis was performed.The stiffness of the tibial nerve, as measured as mean, minimum or maximum elasticity, was significantly higher in patients in the DPN group than the other groups (P < .05). The tibial nerve of subjects in the non-DPN group was significantly stiffer compared to the control group (P < .05). There was no significant difference of the tibial nerve CSA among the 3 groups (P > .05). Mean elasticity of the tibial nerve with a cutoff of 71.3 kPa was the most sensitive (68.3%) and had a higher area under the curve (0.712; 0.602–0.806) among the 3 shear elasticity indices for diagnosing DPN when used alone. When combining SWE with TCSS in diagnosing DPN, the most effective parameter was the EMax, which yielded a sensitivity of 100.00% and a specificity of 95.24%.SWE is a better diagnostic tool for DPN than the conventional ultrasonic parameter CSA, and a higher diagnostic value is attained when combining SWE with TCSS.     

Comparing the accuracy between shear wave elastography and strain elastography in the diagnosis of breast tumors: Systematic review and meta-analysis

Background:Shear wave elastography and strain elastography are two new ultrasonic techniques developed rapidly in recent years. Changes in tissue elasticity occur after normal tissue changes. Elastography technique transforms the elastic information of tissue into optical information for display. Thus more intuitive display of tissue elasticity. Due to the differences in principles and related imaging parameters between the two elastic imaging methods, and the acquisition and interpretation of image data in strain elastic imaging method largely depends on the experience of inspectors, and due to the significant differences between the techniques of inspectors, As a result, conflicting results have been obtained in different scholars’ studies on the accuracy comparison of the two elastography techniques in the diagnosis of breast tumors. This meta-analysis aims to compare the accuracy of the two elastography methods in the diagnosis of breast tumors, so as to provide more accurate diagnostic means for patients with breast tumors. The final results will show which elastography method is more accurate in the diagnosis of breast tumors, reduce unnecessary biopsies and provide a reference for clinical decision making.Methods:We will examine published and unpublished randomized controlled trials, observational studies and abstracts without publication type or language restrictions, and search relevant literatures in PubMed, Web of Science, Wanfang Database, CNQI and other databases until December 30, 2020. The authors will independently search relevant literature records, scan titles and abstracts, full text, collect data and assess the risk of bias. Data will be analyzed by using Meta Disc1.4 software and Stata14.0 software. Heterogeneity tests and combined sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio, and area under the summary receiver operating characteristic curve will be performed by using Meta Disc1.4 software. Stata14.0 software will be used for sensitivity analysis and publication bias test.Results:The results of this systematic review will demonstrate the accuracy of the two elastography methods in the diagnosis of breast tumors.Discussion:The results will provide useful evidence for the comparison of the diagnostic accuracy of shear wave elastography and strain elastography in breast tumors.Other:This study was not funded. Register name: PROSPERO. Registration number: CRD42021251110.     

Ultrasound-based elastography for the diagnosis of portal hypertension in cirrhotics

Progressive fibrosis is encountered in almost all chronicliver diseases. Its clinical signs are diagnostic in advanced cirrhosis, but compensated liver cirrhosis is harder to diagnose. Liver biopsy is still considered the reference method for staging the severity of fibrosis, but due to its drawbacks(inter and intra-observer variability, sampling errors, unequal distribution of fibrosis in the liver, and risk of complications and even death), non-invasive methods were developed to assess fibrosis(serologic and elastographic). Elastographic methods can be ultrasound-based or magnetic resonance imaging-based. All ultrasoundbased elastographic methods are valuable for the early diagnosis of cirrhosis, especially transient elastography(TE) and acoustic radiation force impulse(ARFI) elastography, which have similar sensitivities and specificities, although ARFI has better feasibility. TE is a promising method for predicting portal hypertension in cirrhotic patients, but it cannot replace upper digestive endoscopy. The diagnostic accuracy of using ARFI in the liver to predict portal hypertension in cirrhotic patients is debatable, with controversial results in published studies. The accuracy of ARFI elastography may be significantly increased if spleen stiffness is assessed, either alone or in combination with liver stiffness and other parameters. Two-dimensional shearwave elastography, the Elast PQ technique and strain elastography all need to be evaluated as predictors of portal hypertension.     

Renal tissue elasticity by acoustic radiation force impulse: A prospective study of healthy kidney donors

Background:Some studies reported the correlations between renal parenchymal stiffness measured by transient elastography or acoustic radiation force impulse (ARFI) and the extent of interstitial fibrosis. This study was prospectively designed to evaluate the correlation between clinical, histological findings and the kidney shear wave velocity (SWV, m/s) assessed by ARFI elastography to identify factors affecting the kidney SWV in normal patients.Methods:Seventy-three adult living kidney transplantation donors were enrolled in our center between September 2010 and January 2013. Before transplantation, all donors were evaluated by ARFI elastography to identify the range of SWV in kidneys. Time-zero biopsies were performed on all graft kidneys before implantation.Results:Mean age of donors was 42.0 ± 11.3 years. The mean SWV and depth were 2.21 ± 0.58 m/s and 5.37 ± 1.06 cm. All histological findings showed mild degree of the Banff score, only grade I. In univariate analyses, the SWV was not associated with all histological parameters. Age (r = -0.274, P = .019) diastolic blood pressure (DBP, r = -0.255, P = .030) and depth for SWV measurement (r = -0.345, P = .003) were significantly correlated with the SWV. In multivariate linear regression analysis, age, gender, body mass index (BMI), and depth for SWV measurement were significantly correlated with the SWV (P = .003, .005, .002, and .004, respectively).Conclusions:We demonstrated that all histological findings are not correlated with the SWV of donor kidney. Otherwise, factors influencing the kidney SWV assessed by ARFI elastography are age, gender, BMI, and depth for the SWV measurement in donors for kidney transplantation.     

A simple single slice method for measurement of left and right ventricular enlargement by electron beam tomography

Rationale and objective:We devised to test the feasibility of measuring the left and right ventricular sizes by non-contrast electron beam tomographic images. Methods:Ventricular sizes consist of the sum of the intracavitary cavity and myocardial mass for each ventricle. A total of 50 image studies from subjects undergoing contrast-enhanced studies were used to develop the measurement methodology. About 20 contrast studies were used to test the measure. The methodology was then prospectively tested on 75 patients with non-contrast studies to estimate the intra-observer, inter-observer and inter-study reproducibility. Results:Multiple linear regression analysis was completed and the correct regression formulas to calculate ventricular volumes were acquired by using the area and span from the contrast studies. There was excellent correlation between the estimate of LV (r > 0.97, p < 0.001) and RV (r > 0.93, p < 0.001) sizes between measured and calculated (contrast, single slice) left and right ventricular volumes. The intra-observer, inter-observer and inter-study reproducibility demonstrated excellent results with <7% difference in absolute values and a high correlation (r > 0.89, p < 0.001). Conclusion:We conclude that the left and right ventricular sizes can be accurately estimated from a single mid-ventricular slice on non-contrast electron beam tomographic images.     

Performance of an AI based CAD system in solid lung nodule detection on chest phantom radiographs compared to radiology residents and fellow radiologists

BackgroundDespite the decreasing relevance of chest radiography in lung cancer screening, chest radiography is still frequently applied to assess for lung nodules. The aim of the current study was to determine the accuracy of a commercial AI based CAD system for the detection of artificial lung nodules on chest radiograph phantoms and compare the performance to radiologists in training.MethodsSixty-one anthropomorphic lung phantoms were equipped with 140 randomly deployed artificial lung nodules (5, 8, 10, 12 mm). A random generator chose nodule size and distribution before a two-plane chest X-ray (CXR) of each phantom was performed. Seven blinded radiologists in training (2 fellows, 5 residents) with 2 to 5 years of experience in chest imaging read the CXRs on a PACS-workstation independently. Results of the software were recorded separately. McNemar test was used to compare each radiologist’s results to the AI-computer-aided-diagnostic (CAD) software in a per-nodule and a per-phantom approach and Fleiss-Kappa was applied for inter-rater and intra-observer agreements.ResultsFive out of seven readers showed a significantly higher accuracy than the AI algorithm. The pooled accuracies of the radiologists in a nodule-based and a phantom-based approach were 0.59 and 0.82 respectively, whereas the AI-CAD showed accuracies of 0.47 and 0.67, respectively. Radiologists’ average sensitivity for 10 and 12 mm nodules was 0.80 and dropped to 0.66 for 8 mm (P=0.04) and 0.14 for 5 mm nodules (P<0.001). The radiologists and the algorithm both demonstrated a significant higher sensitivity for peripheral compared to central nodules (0.66 vs. 0.48; P=0.004 and 0.64 vs. 0.094; P=0.025, respectively). Inter-rater agreements were moderate among the radiologists and between radiologists and AI-CAD software (K’=0.58±0.13 and 0.51±0.1). Intra-observer agreement was calculated for two readers and was almost perfect for the phantom-based (K’=0.85±0.05; K’=0.80±0.02); and substantial to almost perfect for the nodule-based approach (K’=0.83±0.02; K’=0.78±0.02).ConclusionsThe AI based CAD system as a primary reader acts inferior to radiologists regarding lung nodule detection in chest phantoms. Chest radiography has reasonable accuracy in lung nodule detection if read by a radiologist alone and may be further optimized by an AI based CAD system as a second reader.     

Three-Dimensional Reconstruction Modeling of the Spatial Displacement,Extent and Rotational Orientation of Undisplaced Femoral Neck Fractures

The purpose of this study was to employ a new three-dimensional (3D) reconstruction and modeling method to measure displacement of undisplaced femoral neck fractures (Garden stages I and II). We also aimed to evaluate the effectiveness of the Garden classification for determining the displacement of undisplaced femoral neck fractures.A total of 120 consecutive patients with undisplaced femoral neck fractures were enrolled between 2012 and 2014, including 60 within the Garden I group and 60 within the Garden II group. The displacements of the femoral head center (d1) and the lowest point of the fovea capitis femoris (d2) and rotational displacement of the femoral head (α) in the 3D model were measured with 3D computed tomography reconstruction and modeling. Five observers, trauma surgeons, were asked to found the centers of the femoral heads and the deepest points of the foveae. The intraobserver and inter-observer agreements were calculated using Fleiss’ kappa.The inter-observer and intra-observer kappa values were 0.937 and 0.985, respectively. Current method has good reliability. We discovered that many participants in our study had been misclassified by an anterior–posterior radiograph as having an “incomplete” fracture. In incomplete fracture of Garden stage I group, the average displacements d1 and d2 were 3.69 ± 1.77 mm and 14.51 ± 1.91 mm, respectively. The mean α was 4.91° ± 2.49°. For impacted fracture of Garden stage I, significant spatial displacement in the impacted fractures was observed (d1: 6.22 ± 3.36 mm; d2: 10.30 ± 5.73 mm; and α: 17.83° ± 10.72°). Similarly, significant spatial displacement was observed among the Garden stage II group (d1: 7.16 ± 4.58 mm; d2: 12.95 ± 8.25 mm; and α: 18.77° ± 9.10°). There was no significant difference in α, d1, and d2 between impacted fracture and Garden stage II groups (P > 0.05). However, significant differences were found between incomplete fracture and Garden stage II groups (P < 0.05).Our findings suggest that 3D reconstruction and modeling may be a better tool for assessing femoral neck fractures than the Garden classification. Undisplaced femoral neck fractures showed variable degrees of displacement and were not undisplaced, stable fractures. Garden classification for undisplaced femoral neck fractures has certain limitations.     

Shear wave elastography of the ulnar nerve at the forearm

The study included 38 ulnar nerves in 20 healthy subjects. High-resolution ultrasound and Shear wave elastography were used to evaluate the ulnar nerve at the mid forearm. The mean cross-sectional area of the ulnar nerve was 7.1 mm². The mean shear elastic modulus of the nerve in the short axis was 27.4 kPa. The mean shear elastic modulus of the nerve in long axis was 24.7 kPa. No statistical relation could be noted between elasticity measurements in long and short axes. The ulnar nerve elastic modulus also showed no correlation with CSA neither in the long axis nor short axis. Age, height, weight, and body mass index showed no correlation with the ulnar elastic modulus in short or long axes. The elastic modulus of the ulnar nerve has been determined in healthy subjects and can serve as a reference for future assessment of compressive neuropathies of the ulnar nerve.     

Brain palpation from physiological vibrations using MRI

We present a magnetic resonance elastography approach for tissue characterization that is inspired by seismic noise correlation and time reversal. The idea consists of extracting the elasticity from the natural shear waves in living tissues that are caused by cardiac motion, blood pulsatility, and any muscle activity. In contrast to other magnetic resonance elastography techniques, this noise-based approach is, thus, passive and broadband and does not need any synchronization with sources. The experimental demonstration is conducted in a calibrated phantom and in vivo in the brain of two healthy volunteers. Potential applications of this “brain palpation” approach for characterizing brain anomalies and diseases are foreseen.The complexity of wave fields can sometimes be an advantage for imaging. Such is the case in multiple scattering or reverberating media, where wave fields contain information about their sources and the medium itself. Turning this wave noise into useful measurements through correlation techniques has provided a breakthrough in a wide variety of domains, which range from seismology (1) to acoustics (2, 3) and electromagnetism (4). Living tissue is also full of unexploited vibrations. Their detection with ultrafast ultrasound scanners that can reach thousands of frames per second (5–7) has recently opened up the medical field to correlation techniques and therefore, passive elastography (8). However, ultrasound is not suitable for brain imaging. MRI can image the brain, but its relatively low acquisition rate of a few frames per second is an issue. Synchronization with the shear-wave source is, thus, necessary (9, 10), which penalizes its potential implementation based on natural shear waves.We describe a magnetic resonance elastography (MRE) -based method that is free from the need for synchronization and any controlled source. This approach extracts information related to the mechanical properties of the soft tissue from hundreds of snapshots of randomly fluctuating shear-wave fields. The key to decrypting the complex field is correlation or similarly but from a physical point of view, time reversal (11, 12). Not only does this wide-band approach maximize the signal-to-noise ratio, as any matched filter would, but it also avoids the Nyquist–Shannon problem that is inherent to slow imaging devices. Indeed, although time information is definitely lost, the spatial information is still present and allows shear-wavelength tomography to be conducted. This wavelength is closely related to the shear elasticity and thus, the intuitive estimation of the stiffness felt by physicians during palpation examination. To start, this concept is shown using MRI in a calibrated elastography phantom under randomly sampled vibrations. Arterial pulsation can produce motion in the brain as high as 1 mm (13); the resulting natural shear-wave field is analyzed through correlation algorithms, and passive brain palpation reconstructions are presented.     

Inter- and intra-observer variability in detection and progression assessment with MRI of microadenoma in Cushing’s disease patients followed up after bilateral adrenalectomy

OBJECTIVE: To assess the inter- and intra-observer variability in detection and progression assessment with MRI of pituitary microadenomas in cases of Cushing's disease treated by adrenalectomy. DESIGN AND METHODS: Two radiologists independently reviewed initial and follow-up MRI studies of 32 patients with a history of Cushing's disease on two occasions each. Five classical qualitative signs and three quantitative measurements of microadenoma were considered. Intra and inter-observer reproducibility was evaluated with kappa statistics (qualitative signs) and intraclass correlation coefficients and Bland-Altman plots (quantitative measurements). RESULTS: No sign or measurement could be identified as better than others and none displayed consistently high levels of inter- or even intra-observer reproducibility (kappa or intraclass correlation coefficient > 0.80). Both qualitative and quantitative criteria showed lower reproducibility when used for diagnosing progression than when used for diagnosing the presence of an adenoma. Reproducibility of qualitative signs appeared to be influenced by reader's experience. CONCLUSIONS: Pituitary MRI study of patients with Cushing disease treated by adrenalectomy remains difficult. In practice, interpretation of MRI studies by a well-experienced reader should be preferred, unless a final decision can be reached by consensus between two and several readers.     

2D Ultrasound and 3D MR Image Registration of the Prostate for Brachytherapy Surgical Navigation

Two-dimensional (2D) ultrasound (US) images are widely used in minimally invasive prostate procedure for its noninvasive nature and convenience. However, the poor quality of US image makes it difficult to be used as guiding utility. To improve the limitation, we propose a multimodality image guided navigation module that registers 2D US images with magnetic resonance imaging (MRI) based on high quality preoperative models. A 2-step spatial registration method is used to complete the procedure which combines manual alignment and rapid mutual information (MI) optimize algorithm. In addition, a 3-dimensional (3D) reconstruction model of prostate with surrounding organs is employed to combine with the registered images to conduct the navigation. Registration accuracy is measured by calculating the target registration error (TRE). The results show that the error between the US and preoperative MR images of a polyvinyl alcohol hydrogel model phantom is 1.37 ± 0.14 mm, with a similar performance being observed in patient experiments.     

Multimodal ultrasound imaging of primary thyroid schwannoma: A case report

Rationale:Primary schwannoma of the thyroid gland is very rare, and its preoperative diagnosis is difficult.Patient concerns:We report the case of a thyroid nodule in an 18-year-old woman, who presented with a mass in her left neck with stiffness and normal thyroid function. However, the patient complained of numbness in her left upper extremity, and ultrasound (US) features were suspicious of malignancy.Diagnoses:Multimodal US imaging was performed using B-mode, color doppler, ultrasonic elastography (UE), and contrast-enhanced ultrasound (CEUS). CEUS revealed heterogeneous enhancement and “target sign” within the tumor. The nodule was suspicious for malignancy and classified as TI-RADS 4b, while the elasticity values measured by UE indicated a benign lesion. Fine needle aspiration (FNA) was subsequently performed in the markedly contrast-enhanced area for biopsy. Cytological results revealed a benign schwannoma.Intervention:The patient underwent left lobe resection. Postoperative pathology confirmed it to be a primary benign schwannoma of the thyroid.Outcomes:After thyroidectomy, the patient was followed-up with US. At present, all laboratory tests and thyroid imaging are normal, and the numbness of the left upper limb has disappeared.Lessons:The combination of different US modalities is useful for the diagnosis of thyroid lesions. FNA performed under CEUS guidance improves the accuracy of biopsy sampling.     

Pre-surgical peripheral blood inflammation markers predict surgical site infection following mesh repair of groin hernia

Surgical site infection (SSI) is a costly postoperative complication with a decrease in the quality of life. We aimed to probe the predictive role of peripheral blood inflammation markers for SSI following mesh repair of groin hernia (GH).This retrospective study assessed the data of 1177 patients undergoing elective mesh repair of GH (open/laparoscopy) in the absence of antibiotic prophylaxis. The relation between demographics, surgical factors, pre-surgical laboratory results and the occurrence of SSI were investigated by univariate and multivariate analyses. Receiver operating characteristic analysis was performed to determine the optimal threshold of parameters and compare their veracity.The overall SSI rate was 3.2% with 1-year follow-up (38 superficial and 1 deep SSI). Patients with SSI had significant higher pre-surgical neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) than those without (P = .029 and P = .045, respectively); their NLR and PLR correlated positively with postoperative total days of antibiotic treatment for SSI (r = .689, P = .000; r = .493, P = .001; respectively). NLR and PLR had larger areas under the receiver operating characteristics curves than neutrophil (.875 vs. .601; P = .000; .726 vs. .601; P = .017). The combination of PLR and neutrophil/NLR raised the predictive sensitivity of PLR for SSI (sensitivity: PLR: 74.36%; PLR + neutrophil: 82.05%; PLR + NLR: 83.57%). On multivariate analyses, higher preoperative NLR (cut-off 2.44) and PLR (cut-off 125.42) were independent predictors for SSI.Higher pre-surgical NLR and PLR may be valuable predictors for SSI following elective mesh repair of GH.     

Quantitative analysis of vascularity for thyroid nodules on ultrasound using superb microvascular imaging: Can nodular vascularity differentiate between malignant and benign thyroid nodules?

This study aimed to investigate the utility of adding superb microvascular imaging (SMI) to B-mode ultrasound (US) for distinguishing between benign and malignant thyroid nodules and evaluate the usefulness of SMI quantification of nodular vascularity for diagnosing thyroid cancer.The malignancy likelihood was scored for 3 datasets before versus after additional color Doppler imaging or SMI using 4-scale visual analysis (i.e., B-mode US alone, B-mode US + color Doppler image, and B-mode US + SMI). Further, the SMI pixel count was measured in the region of interest, including the whole nodule, on the longitudinal view. It was compared between benign and malignant nodules and analyzed according to the US patterns of thyroid nodules based on the Korean thyroid imaging reporting and data system. We calculated the area under the receiver operating characteristic curve values, sensitivities, and specificities.There was no significant difference in the area under the receiver operating characteristic curve values among B-mode, B-mode + color Doppler, and B-mode + SMI. However, the SMI pixel count was significantly higher in malignant thyroid nodules than in benign ones. The optimal cut-off value for the SMI pixel count for predicting malignant thyroid nodules obtained using a receiver operating characteristic curve was 17 (40.54% in sensitivity, 91.3% in specificity). Analysis based on the US pattern of thyroid nodules revealed significant differences in the nodules with low-to-intermediate suspicious US features between malignant and benign nodules.Quantification analysis of vascularity using SMI can differentiate malignant thyroid nodules from benign ones.     

Prospective cohort study comparing transient EUS guided elastography to EUS-FNA for the diagnosis of solid pancreatic mass lesions

BackgroundSemiquantitative EUS-elastography has been introduced to distinguish between malignant and benign pancreatic lesions. This study investigated whether semiquantitative EUS-guided transient real time elastography increases the diagnostic accuracy for solid pancreatic lesions compared to EUS-FNA.Patients and methodsThis single centre prospective cohort study included all patients with solitary pancreatic lesions on EUS during one year. Patients underwent EUS-FNA and semiquantitative EUS-elastography during the same session. EUS and elastography results were compared with final diagnosis which was made on the basis of tissue samples and long-term outcome.Results91 patients were recruited of which 68 had pancreatic malignancy, 17 showed benign disease and 6 had cystic lesions and were excluded from further analysis. Strain ratios from malignant lesions were significantly higher (24.00; 8.01–43.94 95% CI vs 44.00; 32.42–55.00 95% CI) and ROC analysis indicated optimal cut-off of 24.82 with resulting sensitivity, specificity and accuracy of 77%, 65% and 73% respectively. B-mode EUS and EUS-FNA had an accuracy for the correct diagnosis of malignant lesions of 87% and 85%. When lowering the cut-off strain ratio for elastography to 10 the sensitivity rose to 96% with specificity of 43% and accuracy of 84%, resulting in the least accurate EUS-based method. This was confirmed by pairwise comparison.ConclusionSemiquantitative EUS-elastography does not add substantial value to the EUS-based assessment of solid pancreatic lesions when compared to B-mode imaging.     

Improving Depiction of Temporal Bone Anatomy With Low-Radiation Dose CT by an Integrated Circuit Detector in Pediatric Patients: A Preliminary Study

The purpose of this study was to determine the performance of low-dose computed tomography (CT) scanning with integrated circuit (IC) detector in defining fine structures of temporal bone in children by comparing with the conventional detector.The study was performed with the approval of our institutional review board and the patients’ anonymity was maintained. A total of 86 children <3 years of age underwent imaging of temporal bone with low-dose CT (80 kV/150 mAs) equipped with either IC detector or conventional discrete circuit (DC) detector. The image noise was measured for quantitative analysis. Thirty-five structures of temporal bone were further assessed and rated by 2 radiologists for qualitative analysis. κ Statistics were performed to determine the agreement reached between the 2 radiologists on each image. Mann–Whitney U test was used to determine the difference in image quality between the 2 detector systems.Objective analysis showed that the image noise was significantly lower (P < 0.001) with the IC detector than with the DC detector. The κ values for qualitative assessment of the 35 fine anatomical structures revealed high interobserver agreement. The delineation for 30 of the 35 landmarks (86%) with the IC detector was superior to that with the conventional DC detector (P < 0.05) although there were no differences in the delineation of the remaining 5 structures (P > 0.05).The low-dose CT images acquired with the IC detector provide better depiction of fine osseous structures of temporal bone than that with the conventional DC detector.     

Mucosal patterns of Helicobacter pylori-related gastritis without atrophy in the gastric corpus using standard endoscopy

AIM:To identify the mucosal patterns of Helicobacter pylori(H.pylori )-related gastritis in the gastric corpus using standard endoscopy and to evaluate their reproducibility.METHODS:A total of 112 consecutive patients underwent upper gastrointestinal endoscopy.The endoscopists classified the endoscopic findings into 4 patterns.In the second part of the study,90 images were shown to 3 endoscopists in order to evaluate the inter-observer and intra-observer variability in image assessment.RESULTS:The mucosal p...