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Combing with the professional characteristics of imaging technology, Radiological Department of West China Hospital, Sichuan University established the STAR training model for imaging technologists to cultivate the scientific research quality of young technicians, which includes sub-professional group training, tutor responsibility system, arrangement of research time, and reading-film session of technologists. Practice shows that this training model has made a series of achievements so far, such as that the number of publishing articles, funds application, authorized patents and oral presentation at international congress has been significantly increased. In addition, there is a high recognition of the STAR training model among young imaging technologists. Therefore, the STAR model can stimulate the scientific research passion of young technologists, and improve their scientific research capability.
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Objective:To explore the application effect of case-based learning (CBL) and lecture-based learning (LBL) in the teaching of image post-processing course in the standardized training system of medical imaging technology.Methods:A total of 34 trainees in the standardized training of imaging technology of Batch 2018 in West China Hospital of Sichuan University were divided into the experimental group and the control group according to their student numbers, with 17 students in each group. CBL teaching was carried out in the experimental group, and LBL teaching was carried out in the control group. According to the standardized training course design, after one year of image post-processing course teaching, the teaching effect was evaluated through closed-book examination, questionnaire survey and post-processing test. SPSS 20.0 was used for t-test and Mann-Whitney U test. Results:The scores of closed-book examinations (74.42±6.10) and post-processing test (73.47±6.03) in the experimental group were higher than those in the control group [(69.11±3.70) and (69.08±6.51)], and the difference was statistically significant ( P<0.05). The questionnaire survey showed that the students in the experimental group recognized CBL teaching in terms of learning interests stimulation, classroom atmosphere mobilization, clinical thinking cultivation, self-study ability training, and analysis of difficult and rare cases, etc. Conclusion:In the image post-processing course of standardized training of medical imaging technology, the rational application of CBL teaching mode is helpful to improve students' learning enthusiasm, self-learning ability, comprehensive analysis of clinical ability, practical ability, innovation consciousness and so on.
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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.
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Objective:To explore the application effect of case-based learning (CBL) combined with problem-based learning (PBL) teaching model in refresher training of medical imaging technologists.Methods:The study recruited 46 imaging technologists trained in radiology department in the Batch 2017 and Batch 2018 of West China Hospital of Sichuan University. They were divided into 2 groups: experimental group (23 persons) and control group (23 persons). CBL combined with PBL teaching method was used in the experimental group, and traditional lecture-based learning (LBL) method was used in the control group. The results of attitude evaluation, staged exminations, graduation assessment and operational skill tests were compared between the two groups, and the questionnaire survey was performed to test the affirmation of self-worth of the two groups of interns. SPSS 17.0 was used for chi-square test, independent t test, and Mann-Whitney U test. Results:Theoretical examination results at the second stage, the third stage, completion and operational examination results in the experimental group were significantly higher than those in the control group [(91.17±2.59) vs. (85.26±3.03), (92.00±1.86) vs. (87.43±3.23), (92.39±2.08) vs. (87.04±2.93), (85.70±5.48) vs. (80.87±5.57), P<0.05]. The questionnaire survey showed that such 7 aspects as the stimulation of subject interest, the cultivation of exploration spirit, the exercise of self-learning ability, the establishment of clinical ideas, the analysis of difficult problems, the mastering of practical operations, and the affirmation of self-worth in the experimental group were better than those in the control group, with significant difference ( P<0.05), while the consolidation of theoretical knowledge of the experimental group was not statistically different from the control group ( P>0.05). Conclusion:The reasonable application of CBL combined with PBL teaching model in refresher training of medical imaging technologists is helpful to improve their learning enthusiasm, self-learning ability, clinical analysis ability, practical operation ability, and long-term consolidation of theoretical knowledge.
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Objective:To explore the efficiency of MR psychoradiology examination in screening and classification of psychiatric disorders as well as its potential clinical application.Methods:Retrospective study was conducted for 144 patients with MR psychoradiology examination, who were diagnosed mental disorders based on International Statistical Classification of Diseases and Related Health Problems Tenth Revision (ICD-10) from September 2018 to July 2020 in West China Hospital of Sichuan University. As our previous studies, imaging diagnostic models were constructed based on gray matter volume (GMV) analysis for four kinds of psychiatric disorders, including depression, anxiety disorder, bipolar disorder and schizophrenia. For 120 patients with psychiatric disorders, the GMV change pattern of brain regions was detected and subtyped by MR psychoradiology examination with 50% similarity threshold of the above imaging diagnostic models. The diagnostic efficiency of MR psychoradiology examination was evaluated with references of clinical diagnose. For 24 patients with dementia, brain atrophy was additionally measured by conventional MR examination and MR psychoradiology examination respectively.Results:The sensitivity, specificity, Youden index and accuracy of MR psychoradiology in identifying the four psychiatric disorders were 86.6% (84/97), 69.6% (16/23), 0.56 and 83.3% (100/120), including depression [77.8% (28/36), 69.0% (58/84), 0.47, 71.7% (86/120)], schizophrenia [58.8% (10/17), 91.3% (94/103), 0.50, 86.7% (104/120)], bipolar disorder [42.1% (8/19), 96.0% (97/101), 0.38, 87.5% (105/120)] and anxiety disorder [24.0% (6/25), 100% (95/95), 0.24, 84.2% (101/120)]. As for 24 patients with dementia, 58.3% (14/24) were detected with brain atrophy by conventional MR examination, while 91.7% (22/24) were detected by MR psychoradiology examination.Conclusions:MR psychoradiology can detect the subtle brain structural abnormalities of patients with mental disorders. Although it can′t be used as an independent biomarker for disease diagnosis till now, it is of great help in improving the accuracy and objectivity of diagnosis.
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Objective:To analyze clinical, laboratory and imaging characteristics of different subtypes of linear morphea (LM) , and to propose an appropriate approach to the diagnosis and severity assessment of LM.Methods:Clinical data were collected from patients with clinically and/or pathologically confirmed LM in Department of Dermatology, West China Hospital, Sichuan University from January 2018 to December 2019, and retrospectively analyzed.Results:A total of 107 patients with LM were enrolled into this study, including 63 with LM of the limbs/trunk, 22 with morphea en coup de sabre, 11 with progressive hemifacial atrophy and 11 with eosinophilic fasciitis. Disease severity was evaluated by using the modified localized scleroderma skin severity index (mLoSSI) and localized scleroderma skin damage index (LoSDI) scores in 88 patients, with the mLoSSI scores ranging from 0 to 51 points, and the LoSDI scores ranging from 0 to 40 points. Routine blood examination of 10 patients with eosinophilic fasciitis showed increased eosinophil counts in 4 patients. Thirteen (14.8%) of 88 patients with LM were positive for antinuclear antibody, with titers of ≥ 1∶320. Magnetic resonance imaging (MRI) examination showed ipsilateral cerebral hemisphere atrophy and contralateral white matter hyperintensity on T2-weighted images in 2 out of 4 patients with progressive hemifacial atrophy, myofascial thickening in 26 out of 28 patients with LM of the limbs/trunk (92.9%) , subcutaneous septal and myofascial thickening in all 11 patients with eosinophilic fasciitis.Conclusions:The preliminary assessment of disease activity, severity and prognosis of LM can be made by mLoSSI and LoSDI. MRI examination is recommended for patients with clinical signs of involvement of subcutaneous structures.
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Clinical practice of medical imaging technology undergraduates is a key link in the transformation from imaging technology students to imaging technologists. However, there are a series of problems leading to poor practice effect, e.g., imaging technology involves a lot of learning contents, and the teachers' level is uneven. Based on the above problems, some improvements have been implemented, including the establishment of the admission lecture system and tutor responsibility system, application of pluralistic teaching methods, standardizing the examination system of interns, flexible adjustment of practice time arrangements, training of practice teaching team, and so on. Finally, the quality and effect of undergraduate practice teaching in medical imaging technology has been improved significantly.
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Objective:To explore the application effect of case-based learning combined with problem-based learning teaching model in refresher training of medical imaging technologists.Methods:The study recruited 46 imaging technologists trained in radiology department in the Batch 2017 and Batch 2018 of West China Hospital of Sichuan University. They were divided into 2 groups: experimental group (23 persons) and control group (23 persons). Case-based learning combined with problem-based learning teaching method was used in the experimental group, and traditional lecture-based learning method was used in the control group. 2 test was used for sex distribution comparisons between the two groups, and independent t test was conducted to compare the differences in age, working years, entrance examination results, attitude rating scores, stage examination scores, completion examination scores, and operational examination scores between the two groups. Mann-Whitney U test was used for comparisons of non-parametric variables between the two groups, such as qualifications, occupation title, and questionnaire results.Results:Theoretical examination results at the second stage, the third stage, completion and operational examination results in the experimental group were higher than those in the control group [(91.17±2.59) vs. (85.26±3.03), (92.00±1.86) vs. (87.43±3.23), (92.39±2.08) vs. (87.04±2.93), (85.70±5.48) vs. (80.87±5.57), P<0.05]. The questionnaire survey showed that the stimulation of subject interest, the cultivation of exploration spirit, the exercise of self-learning ability, the establishment of clinical ideas, the analysis of difficult problems, the mastering of practical operations, and the affirmation of self-worth in the experimental group were better than those in the control group, with significant difference [4(3, 4) scores vs. 3(2, 3) scores, 4(3, 4) scores vs. 2(2, 3) scores, 3(3, 4) scores vs. 2(2, 3) scores, 3(3, 4) scores vs. 3(2, 3) scores, 3(3, 4) scores vs. 2(2, 3) scores, 4(3, 4) scores vs. 3(2, 3) scores, 4(3, 4) scores vs. 3(2, 3) scores, P<0.05], while the consolidation of theoretical knowledge of the experimental group was not different from the control group [3(2, 3) scores vs. 3(2, 3) scores, P>0.05]. Conclusions:The reasonable application of case-based learning combined with problem-based learning teaching model in refresher training of medical imaging technologists is helpful to improve their learning enthusiasm, self-learning ability, clinical analysis ability, practical operation ability, and long-term consolidation of theoretical knowledge, and it also can contribute to affirmation of self-worth.
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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.
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Humans , Acceleration , Arteries , Artifacts , Magnetic Resonance AngiographyABSTRACT
Objective@#To investigate the value of multi-arterial phase differential sub-sampling with cartesian ordering (DISCO) technique in the evaluation of hepatic vascular anatomy with gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA).@*Methods@#Forty-eight patients with suspected hepatic malignancy were prospectively enrolled and underwent both of Gd-EOB-DTPA enhanced DISCO MRI and CTA within two weeks. The hepatic arterial anatomy of two examination methods were evaluated by four-point scoring method. The arterial scores between DISCO and CTA images were compared by Wilcoxon test. The difference among multiple arterial scores of DISCO and CTA were compared by Kruskal-Wallis H test respectively.@*Results@#There was no difference of arterial scores in celiac artery, common hepatic artery, proper hepatic artery, left hepatic artery, right hepatic artery, first branch of right hepatic artery, splenic artery, left gastric artery and gastroduodenal artery between DISCO and CTA (P>0.05), but the arterial score of first branch of left hepatic artery [2 (2,2)] was lower than that of CTA [2 (2,3)] (Z=-3.138,P=0.002). In the multiple comparison among different arteries, there were differences between PHA and LAH (P<0.05), B-LHA and B-RHA (P<0.05) in DISCO, but no difference was found in CTA (P>0.05).@*Conclusion@#The DISCO sequence with Gd-EOB-DTPA enhancement MRI can supply comparable image quality to CTA in hepatic artery and its main branches display, which has no ionizing radiation and can also provide more diagnostic information for clinic.
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Objective@#To investigate the application value of multiple-arterial-phase imaging technique with differential sub-sampling with cartesian ordering (DISCO) in the gadoxetate acid disodium enhanced liver MRI.@*Methods@#From September 2017 to March 2018, 56 patients with suspected malignant focal liver disease diagnosed with ultrasound or CT in West China Hospital of Sichuan University were enrolled prospectively, and underwent preoperative enhanced MRI with gadoxetate acid disodium. Patients were divided into 2 groups by random-number table method. Twenty nine patients in group A underwent liver multiple-arterial-phase imaging with DISCO. Twenty seven patients in group B underwent single-arterial-phase imaging with liver acquisition with volume acceleration-flex (LAVA-Flex). The display rate of late-arterial-phase and respiratory motion artifacts of dynamic enhancement images were evaluated. The categorical variables was compared by Chi-square test. The respiratory motion artifacts between the single-arterial-phase and multiple-arterial-phases were compared by Mann-Whitney U test. The artifact scores among the various phases of the multi-arterial phase were compared by Kruskal-Wallis H.@*Results@#Compared to LAVA-Flex [74.1%(20/27)], a higher display rate of late-arterial phase [96.6%(28/29)] was found in DISCO (Group A), and the difference was statistically significant (χ2=5.770, P=0.016). In the evaluation of respiratory motion artifacts, the motion artifacts of the late-arterial images obtained by LAVA-Flex [3(3,4)] were more severe than the DISCO [2(2,3)], and the difference was statistically significant (Z=-3.250, P<0.01). Among the scores of motion artifacts in the 6 phases of DISCO, the artifact scores of phase 1, 2, 3, 4, 5, 6 were [3(3,4)], [2(2,3)], [2(2,3)], [3(2,3)], [3(3,4)] and [3(3,4)], respectively. The motion artifacts of phase 2, 3, 4 were better than phase 1, 5, 6, the differences were statistically significant (P<0.05), but there was no statistical differences among phase 2, 3 and 4 (P>0.05).@*Conclusion@#Compared with single-arterial-phase imaging, multiple-arterial-phases with DISCO using gadoxetate acid disodium can improve the capture rate of late arterial phase and reduce motion artifacts.
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Objective To investigate the value of multi?arterial phase differential sub?sampling with cartesian ordering (DISCO) technique in the evaluation of hepatic vascular anatomy with gadolinium?ethoxybenzyl?diethylenetriamine pentaacetic acid (Gd?EOB?DTPA). Methods Forty?eight patients with suspected hepatic malignancy were prospectively enrolled and underwent both of Gd?EOB?DTPA enhanced DISCO MRI and CTA within two weeks. The hepatic arterial anatomy of two examination methods were evaluated by four?point scoring method. The arterial scores between DISCO and CTA images were compared by Wilcoxon test. The difference among multiple arterial scores of DISCO and CTA were compared by Kruskal?Wallis H test respectively. Results There was no difference of arterial scores in celiac artery, common hepatic artery, proper hepatic artery, left hepatic artery, right hepatic artery, first branch of right hepatic artery, splenic artery, left gastric artery and gastroduodenal artery between DISCO and CTA (P>0.05), but the arterial score of first branch of left hepatic artery [2 (2,2)] was lower than that of CTA [2 (2,3)] (Z=-3.138,P=0.002). In the multiple comparison among different arteries, there were differences between PHA and LAH (P<0.05), B?LHA and B?RHA (P<0.05) in DISCO, but no difference was found in CTA (P>0.05). Conclusion The DISCO sequence with Gd?EOB?DTPA enhancement MRI can supply comparable image quality to CTA in hepatic artery and its main branches display, which has no ionizing radiation and can also provide more diagnostic information for clinic.
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Objective To investigate the application value of multiple?arterial?phase imaging technique with differential sub?sampling with cartesian ordering (DISCO) in the gadoxetate acid disodium enhanced liver MRI. Methods From September 2017 to March 2018, 56 patients with suspected malignant focal liver disease diagnosed with ultrasound or CT in West China Hospital of Sichuan University were enrolled prospectively, and underwent preoperative enhanced MRI with gadoxetate acid disodium. Patients were divided into 2 groups by random?number table method. Twenty nine patients in group A underwent liver multiple?arterial?phase imaging with DISCO. Twenty seven patients in group B underwent single?arterial?phase imaging with liver acquisition with volume acceleration?flex (LAVA?Flex). The display rate of late?arterial?phase and respiratory motion artifacts of dynamic enhancement images were evaluated. The categorical variables was compared by Chi?square test. The respiratory motion artifacts between the single?arterial?phase and multiple?arterial?phases were compared by Mann?Whitney U test. The artifact scores among the various phases of the multi?arterial phase were compared by Kruskal?Wallis H. Results Compared to LAVA?Flex [74.1%(20/27)], a higher display rate of late?arterial phase [96.6%(28/29)] was found in DISCO (Group A), and the difference was statistically significant (χ2=5.770, P=0.016). In the evaluation of respiratory motion artifacts, the motion artifacts of the late?arterial images obtained by LAVA?Flex [3(3,4)] were more severe than the DISCO [2(2,3)], and the difference was statistically significant (Z=-3.250, P<0.01). Among the scores of motion artifacts in the 6 phases of DISCO, the artifact scores of phase 1, 2, 3, 4, 5, 6 were [3(3,4)], [2(2,3)], [2(2,3)], [3(2,3)], [3(3,4)] and [3(3,4)], respectively. The motion artifacts of phase 2, 3, 4 were better than phase 1, 5, 6, the differences were statistically significant (P<0.05), but there was no statistical differences among phase 2, 3 and 4 (P>0.05). Conclusion Compared with single?arterial?phase imaging, multiple?arterial?phases with DISCO using gadoxetate acid disodium can improve the capture rate of late arterial phase and reduce motion artifacts.
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Objective To explore the optimal protocol of lower-extremity contrast-enhanced MRA (CE-MRA) in the evaluation of diabetic foot.Methods Twenty eight healthy volunteers were scanned by CE-MRA in crus twice with parellel imaging factor (PIF) of 3 or 4.The signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR) and image quality of popliteal artery,posterior tibial artery,anterior tibial artery and peroneal artery were compared.Twenty patients with diabetic foot underwent CE-MRA by both of protocol 1 and 2 in leg,crus and foot.Protocol 1 was the traditional Care-bolus protocol and protocol 2 was the optimized K-space center filling delay-time protocol.The difference of two protocols in venous aliasing and in display of femoral artery,popliteal artery,posterior tibial artery,anterior tibial artery,peroneal artery,dorsalis pedis artery,medial plantar artery and lateral plantar artery were compared.The SNR,CNR of two different PIF sequences were compared by paired t test,and the display of artery of crus was compared by Wilcoxon.The display of vessels and venous aliasing of 2 protocols of diabetic foot patients were compared by Wilcoxon.Results In the images of healthy volunteers with PIF of 3,the SNR were 267±84,174±51,147±42;and the CNR were 232 ±83,139±51,108±39 at popliteal artery,posterior tibial artery and peroneal artery.However,in the images with PIF of 4,the SNR were 239±73,157±53,132±35;and CNR were 206±71,124±50,103±33,respectively.Both the SNR and CNR were higher in the former than in the latter(t values were 2.31 to 4.11,P＜0.05).There was no significant difference in the vessel display between the different PIF volunteers (P＞0.05).In the protocol 1 of patients with diabetic foot,the display of popliteal artery,posterior tibial artery,anterior tibial artery,peroneal artery,dorsalis pedis artery,medial plantar artery and lateral plantar artery,the venous aliasing in crus and foot were 3.40±0.82,2.70±0.80,2.50±1.00,2.20±0.77,2.30±0.92,2.15± 1.04,1.45±0.60,2.20± 1.01,2.20± 1.06.And in the protocol 2,they were 3.85±0.37,3.55± 0.69,3.30±0.92,2.90±0.79,3.30±0.92,3.25±0.79,1.95±1.10,3.70±0.47,3.65±0.49,respectively(P＜0.05).All of these parameters of protocol 2 were superior to protocol 1.Conclusion Using a higher PIF properly,setting the personalized K-space center filling delay-time can contribute to improving the image quality of whole lower-extremity MRA in patients with diabetic foot.
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This study was aimed to optimize the methods of magnetic resonance spectroscopy (MRS) to improve its quality in amygdala. Forty-three volunteers were examined at right and left amygdala using stimulated-echo acquisition mode (STEAM), and point-resolved spectroscopy series (PRESS) with and without saturation bands. The Cr-SNR, water-suppression level, water full width at half maximum (FWHM) and RMS noise of three sequences were compared. The results showed that (1) the Cr-SNR and water-suppression lelvel of PRESS with saturation bands were better than that of PRESS without saturation bands and STEAM (P<0.001); (2) the left and right RMS noise was significantly different both using PRESS with saturation bands and using STEAM (P<0.05); (3) there was a positive, significant correlation between Cr-SNR and voxel size (P<0.05). Therefore, PRESS with saturation bands is better than PRESS without saturation bands or STEAM for the spectroscopy of amygdala. It is also useful to make the voxel as big as possible to improve the spectral quality.
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Adult , Female , Humans , Male , Young Adult , Algorithms , Amygdala , Metabolism , Physiology , Artifacts , Magnetic Resonance Spectroscopy , Methods , Pattern Recognition, Automated , Reference StandardsABSTRACT
Objective To provide an automatical method for quality assurance (QA) of magnetic resonance imaging. Methods Digital imaging and communications in medicine (DICOM) protocol was used to control the process of QA calculation and storage;the region of interest was auto delineated by process. Results The parameters of stability calculated by process reflected the equipment states in a certain extent and avoided the subjectivity which referring to the region of interest. Conclusion Automatical QA method brings the convenience to QA work on aspects of acquiring, analysis and data saving.
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Our purpose is to introduce and analyze the data quality assurance (DQA) protocol of functional magnetic resonance imaging (fMRI). A water phantom was scanned to get DQA indexes. An fMRI sequence was used to get signal noise ratio (SNR) and Drift, which was calculated from maximum difference ratio of the average signal intensity in the region of interest (ROI) of image serials. The long period application of this method demonstrated that this DQA protocol can reflect imaging performance and the state of stability of the MRI scanner. Some application experience and discussion involved in DQA were also presented here.
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Humans , Algorithms , Artifacts , Artificial Intelligence , Image Processing, Computer-Assisted , Methods , Magnetic Resonance Imaging , Methods , Phantoms, Imaging , Reference Standards , Quality ControlABSTRACT
Brain atlas provides a spatial reference system on which other images can be interpreted in a consistent way, and it is essential for the brain imaging research. However, because of the differences in structure between occidental and oriental brains, the brain atlas based on Western populations, e. g., the International Consortium for Brain Mapping's 154 T1 Weighted Average Atlas, may not be appropriate for other ethnic groups. Therefore, in the present study, we produce an average brain atlas which is based on the data collected from 100 healthy Chinese volunteers. The differences in brains between the Chinese population and the Western population were also investigated. Comparatively,Chinese brains are wider and shorter in size, and smaller in volume.
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Female , Humans , Male , Asian People , Brain , Physiology , Brain Mapping , Imaging, Three-Dimensional , Magnetic Resonance Imaging , Reference ValuesABSTRACT
Objective To investigate the brain perfusion changes in patients with refractory depressive disorder (RDD) and non-refractory depressive disorder (NDD) using arterial spin labeling (ASL).Methods Present study included 12 patients with RDD, 37 patients with NDD and 42 controls,and their age, sex and handedness were matched among the three groups.FAIR sequences were performed using a 3 T MR imaging system with an 8 channel phase array head coiL The labelled and controled images were subtracted and then averaged to obtain perfusion-weighted images.The first 2 images were excluded to avoid T, equilibrium effects and then voxel based analysis was performed using SPM2. One way ANOVA analysis using age as covariance ( thresholded at P ＜ 0.01 uncorrected) was performed.Results Patients with NDD showed regional alteration of the brain perfusion, mainly involved in two frontal subcortical circuits, i.e. significantly decreased perfusion in the left frontal and thalamus (the limbic thalamo-cortical circuit) whereas significantly increased perfusion in bilateral hippocampi, fight lentiform and left anterior cingulated gyros (the limbic-striatal-pallidal-thalamic circuit).In contrast, patients with RDD presented significantly decreased perfusion involving bilateral frontal areas (the limbic-thalamo-cortieal circuit) whereby no significantly increased perfusion areas were observed.Conclusion In addition to the reported experimental evidences, our results suggest that the RDD is associated with inactivity of bilateral frontal areas, while the NDD is associated with inactivity of left frontal areas and overactivity of bilateral limbic system.