Objective This study aims to obtain a three-dimensional reconstruction model based on magnetic reso-nance imaging(MRI)data of patients with different degrees of unilateral cleft lip and analyze the anatomy and changes in multiple groups of nasolabial muscles under dynamic and static conditions.Methods One normal person and four adult patients with unilateral cleft lip were included,and MRI was performed under static(upper and lower lips closed naturally)and dynamic(pout and grin)conditions.3D Slicer software was used to reconstruct the model and draw the anatomic morphology of nasolabial muscles.The distance between the junction(where the muscle merges into the orbicularis oris)of the levator muscle,zy-gomaticminor muscle,and zygomatic major muscle to the median sagittal plane,the starting point to the junction point,the dynamic and static junction points,and the angle between the connection of dynamic and static junctions and the hori-zontal plane were measured under three kinds of movements,and the ratio was calculated.Results In all patients,un-der dynamic and static conditions,the distance from the muscle junction to the median sagittal plane,their ratios of the cleft side to the non-cleft side were all greater than 1.While the ratios of the distance from the starting point of the mus-cle to the junction point were less than 1.At static conditions,the two ratios of the same muscle increased gradiently with the severity of the cleft,and the ratio of the zygomatic minor muscle was prominent in the same patient.The ratio of the cleft side to the non-cleft side was greater than 1,and the value for comparison was the angle of the line from the static to the dynamic junction and the horizontal plane.Conclusion The symmetry of the insertion site of the orbicularis oris and the linear distance of both sides of the muscle are related to muscle and cleft types.The angle of muscle contraction on the cleft side is greater than that on the non-cleft side.

Objective:To explore the improvement of image quality of different acceleration factors in breath-hold three-dimensional magnetic resonance cholangiopancreatography (3D MRCP) using deep learning (DL) and compressed sensing (CS) technology.Methods:A total of 68 patients who underwent upper abdominal 3D MRCP examination at West China Hospital of Sichuan University from March to August 2023 were prospectively included. The patients were subdivided into three groups randomly with the following paramters: CS group with an acceleration factor of 24 (CS-24); DL-CS group with acceleration factors 24 (DL-CS-24) and 33 (DL-CS-33) respectively. The signal-to-noise ratio (SNR), contrast ratio (CR) and contrast-to-noise ratio (CNR) of the three sets of images were measured, and the overall image quality, background suppression, artifacts, and visibility of bile ducts and pancreatic ducts at all levels were subjectively evaluated. Chi-square test and Friedman test were used to perform statistical analysis on the number of unsatisfactory diagnostic images and subjective and objective indicators of the three groups of sequences respectively.Results:The scanning time of the DL-CS-33 group (9 s) was 30% shorter than that of the CS-24 group and DL-CS-24 group (13s). The images of DL-CS-33 group from 68 patients all met the clinical diagnostic requirements and statistically differences were found between the images from CS-24 group and DL-CS-24 group (all P<0.05). There were no statistically differences in SNR, CR, CNR, overall image quality, artifacts, and visibility scores of bile ducts and pancreatic ducts at all levels between the DL-CS-33 group and the CS-24 group (all P>0.05). The SNR, CR, CNR, intrahepatic bile duct, main pancreatic duct and overall image quality of the DL-CS -24 group were better than those of the CS-24 group (all P<0.05). Conclusions:DL-CS technology could improves breath-hold 3D MRCP image quality with the 24 acceleration factor with no additioanl scanning time. DL-CS technology combined with a high acceleration factor of 33 further reduces scanning time while ensuring overall image quality, providing a fast breath-hold scanning solution.

Objective:To explore the impact of artificial intelligence compressed sensing technology (CS-AI) on image quality in three-dimensional proton density weighted imaging (3D PDWI) of the unilateral hip joint.Methods:High-resolution unilateral hip imaging was conducted on 67 healthy volunteers at West China Hospital of Sichuan University from January to July 2023. Imaging was performed by using CS-AI 3D PDWI sequence with acceleration factors (AF) of 4, 6, 8, and 10, respectively. According to the AF, all subjects were divided into 4 groups: CS-AI 4, CS-AI 6, CS-AI 8 and CS-AI 10, with CS-AI 4 serving as a reference. Recording the scan time, the signal and noise intensity of the femoral head, muscle, and subcutaneous fat were measured by a senior radiologist and the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were then calculated. Additionally, two observers provided ratings for overall image quality and artifacts in the 4 groups, and statistical analysis was performed using the Friedman rank-sum test.Results:The acquisition times for CS-AI 4, CS-AI 6, CS-AI 8, and CS-AI 10 were 5 min 49 s, 3 min 54 s, 2 min 56 s and 2 min 22 s, respectively. Compared to CS-AI 4, the scanning time for CS-AI 6, CS-AI 8, CS-AI 10 were reduced by 32.95%, 50.14%, 59.31%, respectively. The objective evaluation revealed that the SNR and CNR of the femoral head and muscle in groups CS-AI 6, CS-AI 8, and CS-AI 10 were slightly lower than those in group CS-AI 4 ( P<0.05), and the differences were statistically significant. However, no statistically significant differences were found among the 3 groups ( P>0.05). The subjective evaluation indicated that the overall image quality scores of group CS-AI 8 [3 (3,4)] did not significantly differ from those of group CS-AI 4 and CS-AI 6( P>0.05); The mean scores of group CS-AI 4 and CS-AI 6 were 4 (4, 4); Scores of group CS-AI 10 was 3(3, 3), which statistically significant differ from those of the other groups ( P<0.05). The artifacts rating for groups CS-AI 4, CS-AI 6, CS-AI 8 and CS-AI 10 were 4 (4, 4), 4 (4, 4), 3 (3, 4), and 2 (2, 3) respectively. When AF was set to 10, the images exhibited the most severe artifacts ( P<0.05). For other AF values, artifact ratings did not differ significantly ( P>0.05). Conclusion:The CS-AI 3D-PDWI sequence with acceleration factor 8 can acquire high-resolution images of the unilateral hip joint that meet clinical diagnostic requirements while reducing scanning time.

The Department of Radiology of West China Hospital of Sichuan University provides us a teaching model that image-reading combined with problem-based learning (PBL) for radiographer once a month. Based on the problem images and typical cases, after careful image-reading, radiographer is guided to think positively and propose specific solutions to the problems. Then designated personnel gives a detail lecture on related diseases, imaging performance, diagnostic requirements, conventional scanning schemes, operating specifications, common problems and image post-processing, etc., which aims at taking continuing education for radiographers.

Objective:To preliminarily assess the clinical value of sirolimus combined with prednisone in the treatment of Kaposiform hemangioendothelioma (KHE) complicated by Kasabach-Merritt phenomenon (KMP) .Methods:A retrospective study was conducted. General clinical data and relevant data on efficacy and adverse reactions were collected from 36 patients with KHE complicated by KMP, who received oral sirolimus combined with prednisone in Department of Pediatric Surgery, West China Hospital, Sichuan University from January 2011 to January 2018.Results:Among the 36 patients with KHE complicated by KMP, the male-to-female ratio was 1∶0.8; their average age was 15.0 months (range, 4.0 - 60.0 months) , and the average age of onset was 6.3 months (range, 0.8 - 48.0 months) ; 32 (88.9%) patients were diagnosed with mixed KHE, and 4 (11.1%) with deep KHE; the tumor size ranged from 2.5 cm × 4.0 cm to 20.0 cm × 24.0 cm. During the combined treatment, the average duration of prednisone administration was 6.4 weeks (range, 5.0 - 9.0 weeks) , and that of sirolimus administration was 19.3 months (range, 13.0 - 27.0 months) . After 1-5 weeks of combined treatment, platelet counts and fibrinogen levels of the 36 patients gradually returned to normal. After short-term prednisone combined with long-term sirolimus treatment, the average disease severity score decreased from 4.0 before treatment to 2.4 at 6 months and 1.6 at 12 months. After 12 months of the combined treatment, tumors mostly regressed in 32 (88.9%) patients, partially regressed in 3 (8.3%) , showed no obvious change in 1 (2.8%) . During the treatment, common adverse reactions included gastrointestinal discomfort and oral ulcers, no patient discontinued the treatment due to severe adverse reactions, and no drug toxicity-related death occurred.Conclusion:Sirolimus combined with prednisone is effective and safe for the treatment of KHE complicated by KMP.

OBJECTIVE: To compare the image quality of three-dimensional time-of-flight (TOF) magnetic resonance angiography (MRA) with sparse undersampling and iterative reconstruction (sparse TOF) with that of conventional TOF MRA. MATERIALS AND METHODS: This study included 56 patients who had undergone sparse TOF MRA for intracranial artery evaluation on a 3T MR scanner. Conventional TOF MRA scans were also acquired from 29 patients with matched acquisition times and another 27 patients with matched scanning parameters. The image quality was scored using a five-point scale based on the delineation of arterial vessel segments, artifacts, overall vessel visualization, and overall image quality by two radiologists independently, and the data were analyzed using the non-parametric Wilcoxon signed-rank test. Contrast ratios (CRs) of vessels were compared using the paired t test. Interobserver agreement was calculated using the kappa test. RESULTS: Compared with conventional TOF at the same spatial resolution, sparse TOF with an acceleration factor of 3.5 could reduce acquisition time by 40% and showed comparable image quality. In addition, when compared with conventional TOF with the same acquisition time, sparse TOF with an acceleration factor of 5 could also achieve higher spatial resolution, better delineation of vessel segments, fewer artifacts, higher image quality, and a higher CR (p < 0.05). Good-to-excellent interobserver agreement (κ: 0.65–1.00) was obtained between the two radiologists. CONCLUSION: Compared with conventional TOF, sparse TOF can achieve equivalent image quality in a reduced duration. Furthermore, using the same acquisition time, sparse TOF could improve the delineation of vessels and decrease image artifacts.
Acceleration ; Arteries ; Artifacts ; Humans ; Magnetic Resonance Angiography

Objective To explore the clinical application value of second-generation dual-source CT combined with intelligent modulation and iterative reconstruction in emergency aortic dissection imaging.Methods A total of 40 emergency patients with clinical suspected aortic dissection were included in this study.Conventional scanning was performed in the control group,and large-pitch intelligent modulation and iterative reconstruction were performed in the test group.The mean CT value,mean noise,signal noise ratio(SNR),contrast noise ratio(CNR),effective dose,image quality and aortic root image quality were evaluated and analyzed.Results Totally 40 patients successfully completed CT aortic dissection imaging.There was no difference in image quality between the two groups (P＞ 0.05).The quality of aortic root images in the test group was better than that in the control group,and the difference was statistically significant(x2=22.556,P＜0.05).The mean CT value and mean noise of aorta in the control group were slightly higher than those in the test group.However,SNR and CNR in the test group were higher than those in the control group,and the difference was statistically significant (t =-21.042,-15.924,8.530,11.495,P＜0.05).The effective dose of the control group [(10.59±3.89)mSv] was significantly higher than that [(6.39±0.81) mSv] of the test group,the difference was statistically significant (t =-12.327,P＜0.05).Conclusions The combined intelligent modulation technique and iterative reconstruction technique with dual-source CT large pitch scanning can meet the requirements of image quality and reduce the effective dose,and can be used as a conventional imaging method for emergency CT of aortic dissection.

Objective To investigate the feasibility of chemical exchange saturation transfer (CEST) imaging in the measurement of myocardial creatine (Cr) metabolites in phantom model using 3.0 T MR. Methods Five phantoms were made according to the volume percentage of Cr ranging from 10 to 50 mmol/L with an interval of 10 mmol/L. 3.0 T MR examinations with base protocol sequence,sequence with and without ECG were performed. Signal to noise,CrEST effect and Z spectra were analyzed. Comparison of signal noise ratio (SNR) among the three methods was performed using an analysis of variance. Bivariate correlations were obtained through Pearson analysis. Results Phantom studies demonstrated that different concentrations of Cr exhibited significant CEST effect with the three sequences. The SNR obtained by sequences with and without ECG were both higher than that of base sequence (both P<0.05). Moreover,no significance of SNR was found between sequences with and without ECG (P>0.05). There were positive correlation of MTR between sequences with ECG,sequences without ECG and base protocol sequence (r2= 0.974 and 0.997, both P<0.05). Conclusion Compared with base protocol sequence, the optimized sequence with ECG can acquire higher SNR CrEST images,indicating that myocardial CrEST imaging could be performed in clinical practice.

Objective: To analyze the value of combining the virtual monochromatic spectral (VMS) image and adaptive statistical iterative reconstruction V (ASiR-V) in low tube current dual-energy spectral imaging in head CTA, and to explore the optimal VMS and ASiR-V level while reducing the radiation dose. Method: (1) Phantom study: an Anthropomorphic PBU-60 angiographic head phantom was examined on a Revolution CT with spectral imaging mode at two different tube current. Images of different energy levels (at 40, 45, 50, 55, 60, 65 and 70 keV) in A group [the low tube current group (with 280 mA)] were reconstructed with the combination of filtered back projection (FBP), 20%, 40%, 60% and 80% ASiR-V. VMS images at 70 keV in B group [the routine tube current group (with 445 mA)] were reconstructed with FBP only. The standard deviation (SD), signal to noise ratio (SNR) and contrast to noise ratio (CNR) of phantom study were measured and examined by ANOVA variance analysis.(2) Clinical study: to prospectively select 40 patients (randomly divided into A and B groups with 20 patients in each group), the subjective scores of patients were assessed with a 5-point scale system and compared by the Mann-Whitney U test. The radiation dose was recorded and analyzed by t test. Results: (1) Phantom study: there were significant differences in the image noise, CNR of the simulated cerebral vessels at different energy levels of VMS image (P<0.05). VMS images at 40 to 55 keV yielded a higher CNR compared with 70 keV (P<0.05). The SNR and CNR in the low tube current group with ASiR-V 60% and ASiR-V 80% were higher than that of the FBP, ASiR-V 20% and ASiR-V 40% images in the same group (P<0.05). (2) Clinical study: the subjective scores at 55 keV and 60 keV were higher than others (P<0.05). The subject scores of 40,50 and 55 keV were increased as the proportion of ASiR-V increased. (3) The SNR and CNR of the simulated cerebral vessels and subjective scores in of the 55 keV VMS images with ASiR-V 60% and ASiR-V 80% in the low tube current patient group was higher than that of the 70 keV FBP images in the routine tube current group (P<0.05). The radiation dose of A group was lower than B group (t=23.974, P<0.05). Conclusions VMS images in low tube current spectral imaging combined with ASiR-V can significantly reduce radiation dose and ensure image quality in head CTA. The 55 keV VMS images with ASiR-V60% and 80% provide higher image quality.

Objective To assess the value of cardiac magnetic resonance (CMR) imaging in left ventricular structure and function in patients with end stage renal disease (ESRD).Methods Twenty-five patients with ESRD and 10 healthy subjects underwent CMR.Left ventricular end diastolic volume(EDV),end-diastolic diameter(EDD),end-systolic volume(ESV),end-systolic diameter(ESD),stroke volume(SV),ejection fraction(EF),LVM and interventricular septum (IVS) thickness were measured and compared.The parameters from CMR and 2DTTE were compared.Results The EF in patients with ESRD was significantly lower than that in controls (P＜0.001),while ESV,ESD,IVS and LVM were respectively higher than these in controls (P＜0.05).There was no significant difference (P＞0.05) in ESV between CMR and 2DTTE,but EF of CMR was significantly higher than this of 2DTTE (P＜0.05).There was no significant difference (P =0.296) in left ventricular systolic functional category.Bland-Altman plots showed a good agreement between the two methods.Conclusion CMR is a helpful tool to assess left ventricular structure and function in patients with ESRD.