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Objectives: To explore the use of deep learning–constrained compressed sensing (DLCS) in improving image quality and acquisition time for 3D MRI of the brachial plexus. Methods: Fifty-four participants who underwent contrast-enhanced imaging and forty-one participants who underwent unenhanced imaging were included. Sensitivity encoding with an acceleration of 2 × 2 (SENSE4x), CS with an acceleration of 4 (CS4x), and DLCS with acceleration of 4 (DLCS4x) and 8 (DLCS8x) were used for MRI of the brachial plexus. Apparent signal-to-noise ratios (aSNRs), apparent contrast-to-noise ratios (aCNRs), and qualitative scores on a 4-point scale were evaluated and compared by ANOVA and the Friedman test. Interobserver agreement was evaluated by calculating the intraclass correlation coefficients. Results: DLCS4x achieved higher aSNR and aCNR than SENSE4x, CS4x, and DLCS8x (all p < 0.05). For the root segment of the brachial plexus, no statistically significant differences in the qualitative scores were found among the four sequences. For the trunk segment, DLCS4x had higher scores than SENSE4x (p = 0.04) in the contrast-enhanced group and had higher scores than SENSE4x and DLCS8x in the unenhanced group (all p < 0.05). For the divisions, cords, and branches, DLCS4x had higher scores than SENSE4x, CS4x, and DLCS8x (all p ≤ 0.01). No overt difference was found among SENSE4x, CS4x, and DLCS8x in any segment of the brachial plexus (all p > 0.05). Conclusions: In three-dimensional MRI for the brachial plexus, DLCS4x can improve image quality compared with SENSE4x and CS4x, and DLCS8x can maintain the image quality compared to SENSE4x and CS4x. Clinical relevance statement: Deep learning–constrained compressed sensing can improve the image quality or accelerate acquisition of 3D MRI of the brachial plexus, which should be benefit in evaluating the brachial plexus and its branches in clinical practice. Key Points: •Deep learning–constrained compressed sensing showed higher aSNR, aCNR, and qualitative scores for the brachial plexus than SENSE and CS at the same acceleration factor with similar scanning time. •Deep learning–constrained compressed sensing at acceleration factor of 8 had comparable aSNR, aCNR, and qualitative scores to SENSE4x and CS4x with approximately half the examination time. •Deep learning–constrained compressed sensing may be helpful in clinical practice for improving image quality and acquisition time in three-dimensional MRI of the brachial plexus. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to assess biventricular function and mechanics in patients with the chronic high-altitude disease (CHAD) using cardiovascular MRI and explore the possible risk factors associated with ventricular remodeling. Methods: In this prospective study, consecutive CHAD patients and healthy controls at high-altitude (HA) and at sea level (SL) underwent cardiovascular MRI. Right ventricular (RV) and left ventricular (LV) function and global strain parameters were compared. To identify risk factors associated with ventricular remodeling, multiple linear regression analyses were used. Results: A total of 33 patients with CHAD (42.97 years ± 11.80; 23 men), 33 HA (41.18 years ± 8.58; 21 men), and 33 SL healthy controls (43.48 years ± 13.40; 21 men) were included. A Significantly decreased biventricular ejection fraction was observed in patients (all p < 0.05). Additionally, the HA group displayed lower magnitudes of biventricular longitudinal peak strain (PS) (RV, − 13.67% ± 4.05 vs. − 16.22% ± 3.03; LV, − 14.68% ± 2.20 vs. − 16.19% ± 2.51; both p < 0.05), but a higher LV circumferential PS (− 20.74% ± 2.02 vs. − 19.17% ± 2.34, p < 0.05) than the SL group. Moreover, multiple linear regression analyses revealed that HGB (β = 0.548) was related to the LV remodeling index, whereas BUN (β = 0.570) was associated with the RV remodeling index. Conclusions: With the deterioration of RV function in patients with CHAD, LV function was also impaired concomitantly. Hypoxia-induced erythrocytosis may contribute to LV impairment, while BUN was considered an independent risk factor for RV remodeling. Key Points: • A significantly lower biventricular ejection fraction was observed in patients, with a decreased magnitude of left ventricular (LV) peak systolic strain rate (radial and circumferential) and peak diastolic strain rate (all p < 0.05). • High-altitude healthy natives showed a lower biventricular longitudinal peak strain (all p < 0.05). • Hemoglobin was related to LV remodeling (β = 0.548), while BUN (β = 0.570) was independently associated with RV remodeling in CHAD patients. [ABSTRACT FROM AUTHOR]

Objectives: To compare the image quality of three-dimensional breath-hold magnetic resonance cholangiopancreatography with deep learning-based compressed sensing reconstruction (3D DL-CS-MRCP) to those of 3D breath-hold MRCP with compressed sensing (3D CS-MRCP), 3D breath-hold MRCP with gradient and spin–echo (3D GRASE-MRCP) and conventional 2D single-shot breath-hold MRCP (2D MRCP). Methods: In total, 102 consecutive patients who underwent MRCP at 3.0 T, including 2D MRCP, 3D GRASE-MRCP, 3D CS-MRCP, and 3D DL-CS-MRCP, were prospectively included. Two radiologists independently analyzed the overall image quality, background suppression, artifacts, and visualization of pancreaticobiliary ducts using a five-point scale. The signal-to-noise ratio (SNR) of the common bile duct (CBD), contrast-to-noise ratio (CNR) of the CBD and liver, and contrast ratio between the periductal tissue and CBD were measured. The Friedman test was performed to compare the four protocols. Results: 3D DL-CS-MRCP resulted in improved SNR and CNR values compared with those in the other three protocols, and better contrast ratio compared with that in 3D CS-MRCP and 3D GRASE-MRCP (all, p < 0.05). Qualitative image analysis showed that 3D DL-CS-MRCP had better performance for second-level intrahepatic ducts and distal main pancreatic ducts compared with 3D CS-MRCP (all, p < 0.05). Compared with 2D MRCP, 3D DL-CS-MRCP demonstrated better performance for the second-order left intrahepatic duct but was inferior in assessing the main pancreatic duct (all, p < 0.05). Moreover, the image quality was significantly higher in 3D DL-CS-MRCP than in 3D GRASE-MRCP. Conclusion: 3D DL-CS-MRCP has superior performance compared with that of 3D CS-MRCP or 3D GRASE-MRCP. Deep learning reconstruction also provides a comparable image quality but with inferior main pancreatic duct compared with that revealed by 2D MRCP. Key Points: • 3D breath-hold MRCP with deep learning reconstruction (3D DL-CS-MRCP) demonstrated improved image quality compared with that of 3D MRCP with compressed sensing or GRASE. • Compared with 2D MRCP, 3D DL-CS-MRCP had superior performance in SNR and CNR, better visualization of the left second-level intrahepatic bile ducts, and comparable overall image quality, but an inferior main pancreatic duct. [ABSTRACT FROM AUTHOR]