Comparison of deep learning-based reconstruction of PROPELLER Shoulder MRI with conventional reconstruction.

OBJECTIVE: To compare the image quality and agreement among conventional and accelerated periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) MRI with both conventional reconstruction (CR) and deep learning-based reconstruction (DLR) methods for evaluation of shoulder. MATERIALS AND METHODS: We included patients who underwent conventional (acquisition time, 8 min) and accelerated (acquisition time, 4 min and 24 s; 45% reduction) PROPELLER shoulder MRI using both CR and DLR methods between February 2021 and February 2022 on a 3 T MRI system. Quantitative evaluation was performed by calculating the signal-to-noise ratio (SNR). Two musculoskeletal radiologists compared the image quality using conventional sequence with CR as the reference standard. Interobserver agreement between image sets for evaluating shoulder was analyzed using weighted/unweighted kappa statistics. RESULTS: Ninety-two patients with 100 shoulder MRI scans were included. Conventional sequence with DLR had the highest SNR (P < .001), followed by accelerated sequence with DLR, conventional sequence with CR, and accelerated sequence with CR. Comparison of image quality by both readers revealed that conventional sequence with DLR (P = .003 and P < .001) and accelerated sequence with DLR (P = .016 and P < .001) had better image quality than the conventional sequence with CR. Interobserver agreement was substantial to almost perfect for detecting shoulder abnormalities (κ = 0.600-0.884). Agreement between the image sets was substantial to almost perfect (κ = 0.691-1). CONCLUSION: Accelerated PROPELLER with DLR showed even better image quality than conventional PROPELLER with CR and interobserver agreement for shoulder pathologies comparable to that of conventional PROPELLER with CR, despite the shorter scan time.

Comparison of shear wave elastography with gray-scale USG and CT for quantitative evaluation of rectus femoris muscle.

PURPOSE: The purpose of this study was to compare the measurement of shear wave elastography (SWE) and gray scale ultrasonography (GSU) and CT attenuation of mid-rectus femoris (RF) muscle in healthy adults. METHODS: This prospective study included 70 participants with a healthy body mass index (<25 kg/m2 ) between June 2019 and January 2020. Echo intensity (EI) grading of RF on GSU was performed. SWE was performed for the three levels of the RF. Measurements were repeated 10 min after the first measurement. The mid-RF attenuation on CT was also measured. Interobserver agreement of EI grade among three readers was assessed using weighted-kappa statistics. The reliability of SWE was assessed using intraclass correlation coefficient. The correlations between the SWE and CT/GSU measurements were analyzed. RESULTS: Interobserver agreement of EI grade on GSU by the three radiologists was moderate to substantial (k = 0.562-0.767). The inter-session agreements for SWE were almost perfect for mid RF (k = 0.822-0.829) and substantial for proximal and distal RF (k = 0.767-0.795). There were significant correlations between SWE-EI and SWE-CT attenuation (p < 0.001, respectively) at the mid-RF. CONCLUSIONS: SWE measurements on mid-RF demonstrated the highest reliability. SWE parameters showed a strong correlation with EI on GSU and attenuation on CT.

Shear-wave elastography evaluation of thenar muscle in carpal tunnel syndrome.

PURPOSE: We aim to evaluate the shear wave velocity (SWV) of the thenar muscle as an adjunct diagnostic tool for carpal tunnel syndrome (CTS). METHODS: Ninety-two wrists with CTS and 30 control wrists without CTS underwent ultrasonographic evaluation of thenar muscle and median nerve including shear-wave elastography. Cross sectional area (CSA) of medial nerve and SWV of thenar muscle and median nerve were evaluated. CTS patients were assessed for Boston CTS, Padua CTS, modified Hirani grading scores, and nerve conduction study (NCS). SWVs, CSA, and NCS parameters were compared between two groups. RESULTS: The SWVs of thenar muscle and median nerve (p < 0.001, respectively), and CSA of median nerve (p < 0.001) were more significantly greater in patients with CTS than in controls. The SWV of median nerve was moderately correlated with CSA of median nerve (r = 0.35, p < 0.001) and modified Hirani CTS score (r = 0.35, p < 0.001). The SWV of thenar muscle was inversely correlated with modified Hirani CTS score (r = -0.21, p = 0.04). CONCLUSION: The SWV of thenar muscle and median nerve of CTS were significantly increased compared to that of control, and significantly negatively correlated with NCS parameters (modified Hirani CTS score). SWVs may be used as an adjunct diagnostic tool for CTS.

Comparing the clinical application of strain elastography and shear wave elastography for the evaluation of lateral epicondylitis.

PURPOSE: This study aimed to compare the diagnostic performance of gray-scale ultrasound (GSU), strain elastography (SE), and shear wave elastography (SWE) for lateral epicondylitis (LE). METHODS: From November 2018 to March 2021, 87 common extensor tendons (CETs) of 70 patients were evaluated using elbow ultrasound. Patients were divided into two groups: patients with LE and those without lateral elbow pain. GSU, SE, and SWE findings from the two groups were compared, and the diagnostic performance was compared for significant variables. RESULTS: Among the 70 patients, 41 with 44 CETs were clinically diagnosed with LE, and 29 with 43 CETs had no lateral elbow pain. Hypoechogenicity, calcification, and hyperemia were significantly different. Strain ratio (SR), stiffness, and shear wave velocity (SWV) were also significantly different. The diagnostic accuracy of stiffness and SWV was better than that of other significant findings. Furthermore, there were no superiorities in SR, stiffness, or SWV. CONCLUSION: Both SE and SWE can be valuable diagnostic tools for diagnosing LE. The diagnostic performances of both SE and SWE were similar in the detection of LE.

Can Bone Erosion in Axial Spondyloarthropathy be Detected by Ultrashort Echo Time Imaging? A Comparison With Computed Tomography in the Sacroiliac Joint.

BACKGROUND: Structural lesion evaluation in axial spondyloarthropathy (SpA) can improve accuracy of diagnosis. However, structural lesions (bone erosions) are difficult to be assessed using conventional MRI compared to computed tomography (CT). PURPOSE: To evaluate the diagnostic performance of ultrashort echo time (UTE) for detecting bone erosion in axial SpA compared to T1WI and three-dimensional double-echo steady-state (3D DESS) imaging using CT as the reference standard. STUDY TYPE: Retrospective. POPULATION: Fourteen patients (eight females, 57.1%) and 14 healthy controls (seven females, 50.0%) who underwent sacroiliac (SI) joint MRI and CT. FIELD STRENGTH/SEQUENCE: 3 T; TSE T1WI, 3D DESS, 2D UTE. ASSESSMENT: The bilateral SI joints were assessed for bone erosion. Three observers scored bone erosion for all three sequences of MRI. CT was used as the gold standard. Diagnostic confidence in axial SpA was measured based on a four-point confidence score. STATISTICAL TESTS: Correlation of erosion scores between CT and MRI were evaluated using Spearman's correlation test. Sensitivity, specificity, and positive-negative predictive values were calculated. Confidence scores were compared using the Wilcoxon sum rank test. Statistical significance was set at P < 0.05. RESULTS: Compared with erosion scores of CT, the correlation coefficients for each MRI sequence showed significant low-to-high positive correlations (0.39-0.72). UTE imaging showed the highest correlation coefficients for all observers (0.70, 0.72, and 0.67, respectively). The specificity of UTE imaging was equal or higher than those of T1WI and 3D DESS for all observers (0.86 vs. 0.71 vs. 0.57; 0.93 vs. 0.71 vs. 0.57; 0.79 vs. 0.79 vs. 0.43). All observers had the highest confidence in interpreting UTE imaging for detecting bone erosion among the three sequences (3.5, 3.4, and 3.3 for UTE; 3.1, 3.0, and 2.6 for T1WI; and 3.2, 2.7, and 2.4 for DESS). DATA CONCLUSION: UTE imaging can detect bone erosions in patients with axial SpA and show higher specificity than conventional T1WI and 3D DESS. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

Image Quality and Diagnostic Performance of Accelerated Shoulder MRI With Deep Learning-Based Reconstruction.

BACKGROUND. Shoulder MRI using standard multiplanar sequences requires long scan times. Accelerated sequences have tradeoffs in noise and resolution. Deep learning-based reconstruction (DLR) may allow reduced scan time with preserved image quality. OBJECTIVE. The purpose of this study was to compare standard shoulder MRI sequences and accelerated sequences without and with DLR in terms of image quality and diagnostic performance. METHODS. This retrospective study included 105 patients (45 men, 60 women; mean age, 57.6 ± 10.9 [SD] years) who underwent a total of 110 3-T shoulder MRI examinations. Examinations included standard sequences (scan time, 9 minutes 23 seconds) and accelerated sequences (3 minutes 5 seconds; 67% reduction), both including fast spin-echo sequences in three planes. Standard sequences were reconstructed using the conventional pipeline; accelerated sequences were reconstructed using both the conventional pipeline and a commercially available DLR pipeline. Two radiologists independently assessed three image sets (standard sequence, accelerated sequence without DLR, and accelerated sequence with DLR) for subjective image quality and artifacts using 4-point scales (4 = highest quality) and identified pathologies of the subscapularis tendon, supraspinatus-infraspinatus tendon, long head of the biceps brachii tendon, and glenoid labrum. Interobserver agreement and agreement between image sets for the evaluated pathologies were assessed using weighted kappa statistics. In 27 patients who underwent arthroscopy, diagnostic performance was calculated using arthroscopic findings as a reference standard. RESULTS. Mean subjective image quality scores for readers 1 and 2 were 10.6 ± 1.2 and 10.5 ± 1.4 for the standard sequence, 8.1 ± 1.3 and 7.2 ± 1.1 for the accelerated sequence without DLR, and 10.7 ± 1.2 and 10.5 ± 1.6 for the accelerated sequence with DLR. Mean artifact scores for readers 1 and 2 were 9.3 ± 1.2 and 10.0 ± 1.0 for the standard sequence, 7.3 ± 1.3 and 9.1 ± 0.8 for the accelerated sequence without DLR, and 9.4 ± 1.2 and 9.8 ± 0.8 for the accelerated sequence with DLR. Interobserver agreement ranged from kappa of 0.813-0.951 except for accelerated sequence without DLR for the supraspinatus-infraspinatus tendon (κ = 0.673). Agreement between image sets ranged from kappa of 0.809-0.957 except for reader 1 for supraspinatus-infraspinatus tendon (κ = 0.663-0.700). Accuracy, sensitivity, and specificity for tears of the four structures were not different (p > .05) among image sets. CONCLUSION. Accelerated sequences with DLR provide 67% scan time reduction with similar subjective image quality, artifacts, and diagnostic performance to standard sequences. CLINICAL IMPACT. Accelerated sequences with DLR may provide an alternative to standard sequences for clinical shoulder MRI.

Clinical applicability of shear wave elastography for the evaluation of medial epicondylitis.

OBJECTIVES: To evaluate the ability of shear wave elastography (SWE) in diagnosing medial epicondylitis and to compare the diagnostic performance of SWE with that of grey-scale ultrasound (GSU) and strain elastography (SE). METHODS: GSU, SE, and SWE were performed on 61 elbows of 54 patients from March 2018 to April 2019. An experienced radiologist evaluated the GSU findings (swelling, cortical irregularity, hypoechogenicity, calcification, and tear), colour Doppler findings (hyperaemia), SE findings (strain ratio [SR]), and SWE findings (stiffness and shear wave velocity [SWV]). Participants were divided in two groups: patients with clinically diagnosed medial epicondylitis and patients without medial elbow pain. Findings from the two groups were compared, and the receiver operating characteristic (ROC) curves were calculated for significant features. RESULTS: Of the 54 patients, 25 patients with 28 imaged elbows were clinically diagnosed with medial epicondylitis and 29 patients with 33 imaged elbows had no medial elbow pain. Cortical irregularity, hypoechogenicity, calcification, hyperaemia, SR, stiffness, and SWV were significantly different between the two groups. The areas under the ROC curves were 0.838 for hypoechogenicity, 0.948 for SR, 0.999 for stiffness, and 0.999 for SWV. The diagnostic performances of SR, stiffness, and SWV were significantly superior compared to that of hypoechogenicity. However, there were no significant differences among SR, stiffness, and SWV. CONCLUSIONS: SWE can obtain both stiffness and SWV, which are valuable diagnostic tools in the diagnosis of medial epicondylitis. The diagnostic performance of SWE and SE is similar in detecting medial epicondylitis. KEY POINTS: • Shear wave elastography providing stiffness and shear wave velocity showed excellent performance in the diagnosis of medial epicondylitis. • There was no significant difference in the ability of SE and SWE for diagnosing medial epicondylitis.

Comparison of the Diagnostic Performance of Strain Elastography and Shear Wave Elastography for the Diagnosis of Carpal Tunnel Syndrome.

OBJECTIVES: To compare the diagnostic performance between strain elastography and shear wave elastography (SWE) for the diagnosis of carpal tunnel syndrome (CTS). METHODS: Between July 2018 and June 2019, 66 consecutive patients with 95 imaged wrists underwent wrist ultrasound, including grayscale ultrasound, strain elastography, and SWE, because of the suspicion of CTS. During wrist ultrasound, the cross-sectional area (CSA), strain ratio, elasticity, and shear wave velocity of each median nerve were measured at the proximal carpal bone level (scaphoid to pisiform). The variables were compared between the normal and CTS groups by using the independent t test, and subgroup analyses were performed using one-way analysis of variance. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic performance of each variable. RESULTS: CSA, elasticity, and shear wave velocity showed significant intergroup differences (P < 0.001, P < 0.001, and P = 0.002, respectively). However, the strain ratio showed no statistically significant intergroup difference (P = 0.639). In the subgroup analyses, elasticity showed significantly higher values in the severe group than in the mild and moderate groups (P < 0.001 and P = 0.001, respectively). Other parameters showed no significant differences among the different subgroups. The areas under the ROC curve were 0.823 for CSA, 0.772 for elasticity, and 0.779 for shear wave velocity. The differences in the areas under the ROC curve among CSA, elasticity, and shear wave velocity were not statistically significant (all P > 0.05). CONCLUSIONS: SWE has a good diagnostic value in CTS. In particular, elasticity can discriminate the severe group from the other groups.

Intraobserver and interobserver reliability in sonographic size measurements of gallbladder polyps.

OBJECTIVES: To evaluate the intraobserver and interobserver reliability of gallbladder polyp measurements using transabdominal US and the factors that affect reliability. METHODS: From November 2017 to February 2018, two radiologists measured the maximum diameter of 91 gallbladder polyps using transabdominal US. Intraobserver and interobserver agreement were determined using 95% Bland-Altman limits of agreement and intraclass correlation coefficients (ICCs). The effects of image settings, polyp location, and polyp size were evaluated by comparing ICCs using z tests. RESULTS: The intraobserver agreement rates were 0.960 (95% confidence interval [CI], 0.939-0.973) for observer 1 and 0.962 (95% CI, 0.943-0.975) for observer 2. The ICCs between the two observers were 0.963 (95% CI, 0.926-0.979) for the first measurement and 0.973 (95% CI, 0.950-0.984) for the second measurement. The 95% limits of agreement on repeated measurements were 22.3-25.2% of the mean, and those between the two observers were 25.5-34.2% of the mean. ICCs for large polyps (≥ 5 mm) were significantly higher than those for small polyps (< 5 mm). There were no significant differences in the ICCs between image settings and polyp location. CONCLUSIONS: Polyp size measurements using transabdominal US are highly repeatable and reproducible. Polyp size significantly affects the reliability of measurement. Diameter changes of approximately less than 25% may fall within the measurement error; this should be considered while interpreting the change in size during follow-up US, especially for small polyps. KEY POINTS: • Gallbladder polyp size measurement using transabdominal US is highly repeatable and reproducible. • Diameter changes of approximately less than 25% should be interpreted carefully, especially in small polyps.

Ultrasound Features and Rate of Upgrade to Malignancy in Atypical Apocrine Lesions of the Breast.

OBJECTIVES: To evaluate the ultrasound (US) features and rate of upgrade to malignancy in atypical apocrine lesions (AALs) of the breast, diagnosed on percutaneous needle biopsy. METHODS: This retrospective study included 17 AALs diagnosed by needle biopsy in 15 patients. For 16 of the 17 AALs, subsequent surgical excision (n = 14) or 8-gauge vacuum-assisted biopsy (n = 2) was performed. Ultrasound features were retrospectively analyzed according to the American College of Radiology Breast Imaging Reporting and Data System lexicon. RESULTS: Of 17 AALs, 13 (76.5%) were atypical apocrine hyperplasia; 3 (17.6%) were atypical apocrine adenosis; and 1 (5.9%) was combined atypical apocrine hyperplasia and atypical apocrine adenosis on needle biopsy. Subsequently, 4 of 16 AALs (25%) were upgraded to malignancy at surgical excision. On US imaging, all 17 lesions presented as masses, which were mainly irregular and noncircumscribed (n = 8) or oval/round and noncircumscribed (n = 7) with isoechogenicity or hypoechogenicity. Rarely, an AAL would show complex cystic and solid echogenicity (n = 1) or appear as a hypoechoic mass with oval shape and a circumscribed margin (n = 1). CONCLUSIONS: Atypical apocrine lesions of the breast often showed suspicious malignant features on US imaging. Given the high upgrade rate (25%), the diagnosis of an AAL by needle biopsy warrants subsequent surgical excision.

Optimization of T2-weighted imaging for shoulder magnetic resonance arthrography by synthetic magnetic resonance imaging.

Background Synthetic magnetic resonance imaging (MRI) allows reformatting of various synthetic images by adjustment of scanning parameters such as repetition time (TR) and echo time (TE). Optimized MR images can be reformatted from T1, T2, and proton density (PD) values to achieve maximum tissue contrast between joint fluid and adjacent soft tissue. Purpose To demonstrate the method for optimization of TR and TE by synthetic MRI and to validate the optimized images by comparison with conventional shoulder MR arthrography (MRA) images. Material and Methods Thirty-seven shoulder MRA images acquired by synthetic MRI were retrospectively evaluated for PD, T1, and T2 values at the joint fluid and glenoid labrum. Differences in signal intensity between the fluid and labrum were observed between TR of 500-6000 ms and TE of 80-300 ms in T2-weighted (T2W) images. Conventional T2W and synthetic images were analyzed for diagnostic agreement of supraspinatus tendon abnormalities (kappa statistics) and image quality scores (one-way analysis of variance with post-hoc analysis). Results Optimized mean values of TR and TE were 2724.7 ± 1634.7 and 80.1 ± 0.4, respectively. Diagnostic agreement for supraspinatus tendon abnormalities between conventional and synthetic MR images was excellent (κ = 0.882). The mean image quality score of the joint space in optimized synthetic images was significantly higher compared with those in conventional and synthetic images (2.861 ± 0.351 vs. 2.556 ± 0.607 vs. 2.750 ± 0.439; P < 0.05). Conclusion Synthetic MRI with optimized TR and TE for shoulder MRA enables optimization of soft-tissue contrast.

Articular cartilage grading of the knee: diagnostic performance of fat-suppressed 3D volume isotropic turbo spin-echo acquisition (VISTA) compared with 3D T1 high-resolution isovolumetric examination (THRIVE).

Background Conventionally, two-dimensional (2D) fast spin-echo (FSE) sequences have been widely used for clinical cartilage imaging as well as gradient (GRE) sequences. Recently, three-dimensional (3D) volumetric magnetic resonance imaging (MRI) has been introduced with one 3D volumetric scan, and this is replacing slice-by-slice 2D MR scans. Purpose To evaluate the image quality and diagnostic performance of two 3D sequences for abnormalities of knee cartilage: fat-suppressed (FS) FSE-based 3D volume isotropic turbo spin-echo acquisition (VISTA) and GRE-based 3D T1 high-resolution isovolumetric examination (THRIVE). Material and Methods The institutional review board approved the protocol of this retrospective review. This study enrolled 40 patients (41 knees) with arthroscopically confirmed abnormalities of cartilage. All patients underwent isovoxel 3D-VISTA and 3D-THRIVE MR sequences on 3T MRI. We assessed the cartilage grade on the two 3D sequences using arthroscopy as a gold standard. Inter-observer agreement for each technique was evaluated with the intraclass correlation coefficient (ICC). Differences in the area under the curve (AUC) were compared between the 3D-THRIVE and 3D-VISTA. Results Although inter-observer agreement for both sequences was excellent, the inter-observer agreement for 3D-VISTA was higher than for 3D-THRIVE for cartilage grading in all regions of the knee. There was no significant difference in the diagnostic performance ( P > 0.05) between the two sequences for detecting cartilage grade. Conclusion FSE-based 3D-VISTA images had good diagnostic performance that was comparable to GRE-based 3D-THRIVE images in the evaluation of knee cartilage, and can be used in routine knee MR protocols for the evaluation of cartilage.

Magnetic resonance arthrography results that indicate surgical treatment for partial articular-sided supraspinatus tendon avulsion: a retrospective study in a tertiary center.

Background Specific findings on magnetic resonance arthrography (MRA) that indicate the need for surgery in patients with partial articular-sided supraspinatus tendon avulsion (PASTA) are not well understood. Purpose To determine which MRA findings are characteristic of patients who undergo surgery for PASTA. Material and Methods From July 2011 to February 2014, MRA findings for patients treated for PASTA were retrospectively reviewed. The patients were divided into two groups: conservative treatment and surgical repair. MRA findings were compared between the groups. The following MRA results were assessed: length grade, width grade, co-existing superior labrum anterior posterior (SLAP) lesions, degenerative changes in the glenohumeral joint, presence of subacromial-subdeltoid bursitis, acromion type, presence of adhesive capsulitis, and tears of the subscapularis or infraspinatus tendon within the rotator cuff. Logistic regression analyses were conducted to identify which MRA findings were significantly associated with surgical treatment. Results Forty-five surgically treated patients and 203 conservatively treated ones were evaluated. The MRA findings showed significant differences between the groups with respect to length grade, width grade, degenerative changes in glenohumeral joint, bursitis, and co-existing rotator cuff tears ( P < 0.05). Multivariate logistic regression showed correlations between surgical repair and both grade 3 length tears (odds ratio, 30.8) and co-existing tears of the subscapularis or infraspinatus tendon (odds ratio, 2.9). Conclusion Surgical treatment is commonly performed in PASTA patients whose lesion lengths are grade 3 or who have co-existing tears in the subscapularis or infraspinatus tendon. Radiologists should pay attention to these MRA signs when evaluating PASTA patients.

Value of the Strain Ratio on Ultrasonic Elastography for Differentiation of Benign and Malignant Soft Tissue Tumors.

OBJECTIVES: The purpose of this study was to evaluate whether the strain ratio provides additional value to conventional visual elasticity scores in the differentiation of benign and malignant soft tissue tumors by ultrasonic elastography. METHODS: The Institutional Review Board approved the protocol of this retrospective review. Seventy-three patients who underwent elastography and had a soft tissue mass pathologically confirmed by ultrasound-guided core biopsy or surgical excision were enrolled from April 2012 through October 2014. On elastography, elasticity scores were determined with a 5-point visual scale, and the strain ratio to adjacent soft tissue at the same depth was calculated. Tumors were divided into benign and malignant groups according to the pathologic diagnoses. Elasticity scores and strain ratios were compared between benign and malignant groups, and diagnostic performance was evaluated by receiver operating characteristic curves. RESULTS: Of the 73 patients, 40 had benign tumors, and 33 had malignant tumors. Strain ratios (P = .003) and elasticity scores (P = .048) were significantly different between pathologic results. The areas under the receiver operating characteristic curves were 0.700 (95% confidence interval, 0.581-0.802) for the strain ratio and 0.623 (95% confidence interval, 0.515-0.746) for elastography. CONCLUSIONS: The strain ratios of malignant soft tissue tumors were lower than those of benign tumors and showed better diagnostic performance than did elasticity scores. The strain ratio can be used as a diagnostic indicator to predict the malignant potential of soft tissue tumors.

Sarcopenia prediction using shear-wave elastography, grayscale ultrasonography, and clinical information with machine learning fusion techniques: feature-level fusion vs. score-level fusion.

This study aimed to develop and evaluate a sarcopenia prediction model by fusing numerical features from shear-wave elastography (SWE) and gray-scale ultrasonography (GSU) examinations, using the rectus femoris muscle (RF) and categorical/numerical features related to clinical information. Both cohorts (development, 70 healthy subjects; evaluation, 81 patients) underwent ultrasonography (SWE and GSU) and computed tomography. Sarcopenia was determined using skeletal muscle index calculated from the computed tomography. Clinical and ultrasonography measurements were used to predict sarcopenia based on a linear regression model with the least absolute shrinkage and selection operator (LASSO) regularization. Furthermore, clinical and ultrasonography features were combined at the feature and score levels to improve sarcopenia prediction performance. The accuracies of LASSO were 70.57 ± 5.00-81.54 ± 4.83 (clinical) and 69.00 ± 4.52-69.73 ± 5.47 (ultrasonography). Feature-level fusion of clinical and ultrasonography (accuracy, 70.29 ± 6.63 and 83.55 ± 4.32) showed similar performance with clinical features. Score-level fusion by AdaBoost showed the best performance (accuracy, 73.43 ± 6.57-83.17 ± 5.51) in the development and evaluation cohorts, respectively. This study might suggest the potential of machine learning fusion techniques to enhance the accuracy of sarcopenia prediction models and improve clinical decision-making in patients with sarcopenia.

Thin-slice elbow MRI with deep learning reconstruction: Superior diagnostic performance of elbow ligament pathologies.

PURPOSE: With the slice thickness routinely used in elbow MRI, small or subtle lesions may be overlooked or misinterpreted as insignificant. To compare 1 mm slice thickness MRI (1 mm MRI) with deep learning reconstruction (DLR) to 3 mm slice thickness MRI (3 mm MRI) without/with DLR, and 1 mm MRI without DLR regarding image quality and diagnostic performance for elbow tendons and ligaments. METHODS: This retrospective study included 53 patients between February 2021 and January 2022, who underwent 3 T elbow MRI, including T2-weighted fat-saturated coronal 3 mm and 1 mm MRI without/with DLR. Two radiologists independently assessed four MRI scans for image quality and artefacts, and identified the pathologies of the five elbow tendons and ligaments. In 19 patients underwent elbow surgery after elbow MRI, diagnostic performance was evaluated using surgical records as a reference standard. RESULTS: For both readers, 3 mm MRI with DLR had significant higher image quality scores than 3 mm MRI without DLR and 1 mm MRI with DLR (all P < 0.01). For common extensor tendon and elbow ligament pathologies, 1 mm MRI with DLR showed the highest number of pathologies for both readers. The 1 mm MRI with DLR had the highest kappa values for all tendons and ligaments. For reader 1, 1 mm MRI with DLR showed superior diagnostic performance than 3 mm MRI without/with DLR. For reader 2, 1 mm MRI with DLR showed the highest diagnostic performance; however, there was no significant difference. CONCLUSIONS: One mm MRI with DLR showed the highest diagnostic performance for evaluating elbow tendon and ligament pathologies, with similar subjective image qualities and artefacts.

Impact of deep learning-based reconstruction and anti-peristaltic agent on the image quality and diagnostic performance of magnetic resonance enterography comparing single breath-hold single-shot fast spin echo with and without anti-peristaltic agent.

Background: While anti-peristaltic agents are beneficial for high quality magnetic resonance enterography (MRE), their use is constrained by potential side effects and increased examination complexity. We explored the potential of deep learning-based reconstruction (DLR) to compensate for the absence of anti-peristaltic agent, improve image quality and reduce artifact. This study aimed to evaluate the need for an anti-peristaltic agent in single breath-hold single-shot fast spin-echo (SSFSE) MRE and compare the image quality and artifacts between conventional reconstruction (CR) and DLR. Methods: We included 45 patients who underwent MRE for Crohn's disease between October 2021 and September 2022. Coronal SSFSE images without fat saturation were acquired before and after anti-peristaltic agent administration. Four sets of data were generated: SSFSE CR with and without an anti-peristaltic agent (CR-A and CR-NA, respectively) and SSFSE DLR with and without an anti-peristaltic agent (DLR-A and DLR-NA, respectively). Two radiologists independently reviewed the images for overall quality and artifacts, and compared the three images with DLR-A. The degree of distension and inflammatory parameters were scored on a 5-point scale in the jejunum and ileum, respectively. Signal-to-noise ratio (SNR) levels were calculated in superior mesenteric artery (SMA) and iliac bifurcation level. Results: In terms of overall quality, DLR-NA demonstrated no significant difference compared to DLR-A, whereas CR-NA and CR-A demonstrated significant differences (P<0.05, both readers). Regarding overall artifacts, reader 1 rated DLR-A slightly better than DLR-NA in four cases and rated them as identical in 41 cases (P=0.046), whereas reader 2 demonstrated no difference. Bowel distension was significantly different in the jejunum (Reader 1: P=0.046; Reader 2: P=0.008) but not in the ileum. Agreements between the images (Reader 1: ĸ=0.73-1.00; Reader 2: ĸ=1.00) and readers (ĸ=0.66 for all comparisons) on inflammation were considered good to excellent. The sensitivity, specificity, and accuracy in diagnosing inflammation in the terminal ileum were the same among DLR-NA, DLR-A, CR-NA and CR-A (94.42%, 81.83%, and 89.69 %; and 83.33%, 90.91%, and 86.21% for Readers 1 and 2, respectively). In both SMA and iliac bifurcation levels, SNR of DLR images exhibited no significant differences. CR images showed significantly lower SNR compared with DLR images (P<0.001). Conclusions: SSFSE without anti-peristaltic agents demonstrated nearly equivalent quality to that with anti-peristaltic agents. Omitting anti-peristaltic agents before SSFSE and adding DLR could improve the scanning outcomes and reduce time.

Ultrasound findings of subpial hemorrhage in neonates.

PURPOSE: Subpial hemorrhage (SPH) is a subtype of intracranial hemorrhage characterized by damage to the adjacent brain parenchyma. The aim of this study was to describe the sonographic features of SPH in neonates. METHODS: The cranial ultrasound (US) findings of neonates with SPH confirmed by brain magnetic resonance imaging (MRI) were analyzed retrospectively. Initial and follow-up US and MRI scans were reviewed by two pediatric radiologists who were blinded to both clinical history and outcomes. The US features were compared with the MRI findings. RESULTS: Sixteen patients were included (median gestational age, 38 weeks; range, 26 to 40 weeks; 69% term). SPH was detected most often in the temporal lobe (63%), and multiple SPHs were found in seven of 16 neonates, based on MRI. Acute SPH with an underlying venous infarct (UVI) was detected on US in 15 of 16 patients: small or large fan-shaped hyperechoic lesions (n=7 and 4, respectively) and gyriform hyperechoic lesions (n=4). The sonographic yin-yang sign was observed in three of the four large fan-shaped SPH cases. The accompanying findings on US were intraventricular hemorrhage (four out of six MRI-confirmed cases), and concurrent periventricular venous infarcts (five out of nine MRI-confirmed cases). In five patients, subpial cysts were observed on follow-up US or MRI (n=4 and n=4, respectively). CONCLUSION: Acute SPH with UVI can appear as a peripheral fan-shaped or gyriform hyperechoic lesion on cranial US. SPH can be detected and suspected based on the US features of SPH with the accompanying findings.

Hounsfield Units Predict Survival of Patients With Estrogen Receptor-Positive and Human Epithelial Growth Factor Receptor 2-Negative Breast Cancer.

BACKGROUNDS: Tumor vascularity plays a fundamental role in cancer progression, including breast cancer. This study aimed to elucidate tumor vascularity and its impact on patient survival in the context of breast cancer subtypes using Hounsfield units (HU) on contrast-enhanced computed tomography (CT). MATERIALS AND METHODS: Patients with early-stage breast cancer who completed planned treatment between 2003 and 2013 were retrospectively assessed. RESULTS: The final cohort comprised 440 patients. Of the 440 patients, 262 had estrogen receptor (ER)-positive disease and 119 had human epidermal growth factor receptor 2 (HER2)-overexpressing disease. The tumor-to-aorta ratio of Hounsfield units (TAR) was related to significantly worse recurrence-free interval (RFI) (P < .001) and overall survival (OS) (P < .001) in patients with TAR > 0.33 for RFI and > 0.35 for OS than their counterparts. In the subgroup analysis, the survival disadvantage was limited only to patients with ER-positive and HER2-negative disease (P < .001 for both RFI and OS). CONCLUSION: This study showed that TAR, which reflects tumor vascularity, was significantly related to patients' RFI and OS, suggesting its capacity as a feasible biomarker. This study also showed that TAR was associated with the survival in patients with ER-positive and HER2-negative disease.

Deep learning based sarcopenia prediction from shear-wave ultrasonographic elastography and gray scale ultrasonography of rectus femoris muscle.

We aim to evaluate the performance of a deep convolutional neural network (DCNN) in predicting the presence or absence of sarcopenia using shear-wave elastography (SWE) and gray-scale ultrasonography (GSU) of rectus femoris muscle as an imaging biomarker. This retrospective study included 160 pair sets of GSU and SWE images (n = 160) from December 2018 and July 2019. Two radiologists scored the echogenicity of muscle on GSU (4-point score). Among them, 141 patients underwent CT and their L3 skeletal muscle index (SMI) were measured to categorize the presence or absence of sarcopenia. For DCNN, we used three CNN architectures (VGG19, ResNet-50, DenseNet 121). The accuracies of DCNNs for sarcopenia classification were 70.0-80.0% (based on SWE) and 65.0-75.0% (based on GSU). The DCNN application to SWE images highlights the utility of deep-learning base SWE for sarcopenia prediction. DCNN application to SWE images might be a potentially useful biomarker to predict sarcopenic status.