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Objective:To evaluate the reporting quality of clinical practice guidelines in medical imaging.Methods:Medical imaging guidelines were searched in CNKI, Wanfang data, CBM, Web of Science, PubMed, and other guideline-related websites. The search period is from January 1, 2017 to February 26, 2022. According to the reporting items for practice guidelines in healthcare (RIGHT) checklist, two researchers separately extracted information from the included guidelines and evaluated the reporting quality, and cross-checked them.Results:Eighteen guidelines in Chinese were included. The average reporting rate was (56.2±14.3) %. The reporting rate of basic information in Domain 1 (75.9%, 82/108) and other information in Domain 7 (68.5%, 37/54) were the highest, while funding and declaration and management of interests in Domain 6 (25.0%, 18/72) had the lowest reporting rate. The included guidelines had a lower reporting rate in item 2 (executive summary of recommendations, 27.8%, 5/18), item 11a (type of systematic review on which the guideline is based, 5.6%, 1/18), item 14a (patient preferences and values, 22.2%, 4/18), item 15 (evidence to decision processes recommendations, 22.2%, 4/18), and item 16 (external review, 16.7%, 3/18).Conclusions:The overall reporting quality of medical imaging guidelines needs to be improved. It is recommended that future guideline developers master the guideline research and evaluation tools, such as the RIGHT statement, and fully report the details and key information to improve the transparency and comprehensiveness of the guidelines.
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Objective:To re-identify the anatomical features of singular nerve canal (SNC) through observing and measuring the morphological characteristics of SNC using ultra-high resolution CT (U-HRCT).Methods:The U-HRCT images of 52 human head specimens (104 ears) from December 2019 to January 2020 were obtained. The best standard cross-sectional and coronal images of SNC were reconstructed. The morphology of the main trunk and branches of the SNC were observed. According to the number of turning points, the trunks of SNC were divided into single turning point type, double turning point type and no turning point type. According to the branch morphology, the branched SNC were divided into bifurcated type, confluent type, side branch type and bilateral branch type. The diameter, angle and length of each section of the posterior canal ampulla (PCA) of the main trunk, the turning point and the internal auditory meatus (IAM) were measured. Independent sample t test or Mann-Whitney U test was used to test group differences of main trunk diameter of the SNC with or without branches. Results:Totally 104 ears of 52 cases were divided into single turning point type of 79 ears, double turning point type of 20 ears and no turning point type of 5 ears. The bilateral morphological classification was the same in 30 cases (60 ears), including 24 cases of single turning point type (48 ears), 5 cases of double turning point type (10 ears), and 1 case of no turning point type (2 ears). The ear morphology on both sides was different in 22 cases (44 ears). The diameters of the PCA, the turning point and the IAM of SNC with single turning point type were (0.31±0.07), (0.40±0.10), (0.46±0.10) mm, respectively, and the angles were 60.5°±7.8°, 120.3°±9.6°, 38.3°±7.5° respectively. And the length of the PCA and the IAM in the SNC with single turning point type were (1.95±0.38), (2.31±0.68) mm, respectively. The diameters of the PCA, the turning point near the PCA, the turning point near the IAM and the IAM of SNC with double turning point type were (0.32±0.09), (0.38±0.09), (0.47±0.12), (0.47±0.13) mm, and the angle were 60.9° (57.3°, 64.9°), 117.9°±12.3°, 129.6°±12.4°, 41.7° (32.9°, 79.5°), respectively. The length of the PCA, the IAM and the distance between these two turning points were (1.78±0.31), 0.65 (0.46, 1.15), 0.96 (0.80, 1.15) mm, respectively. The diameters of the PCA and the IAM of SNC without turning point type were (0.20±0.01) and (0.50±0.12) mm. The angles with the PCA and the IAM in these cases were 58.4°±9.6° and 46.2°±5.1°, and the length was (3.61±0.32) mm. A total of 48 ears had branches, including bifurcated type (36 ears), confluence type (4 ears), side branch type (5 ears) and bilateral branch type (3 ears). In the SNC group with single turning point, the diameter of the turning point in the cases without branches was wider than that of cases with branches ( t=2.11, P=0.039). However, there was no significant difference in the diameter of each section between these two subgroups of SNC cases with double turning point type. Conclusions:U-HRCT is able to clearly show the SNC, the imaging features of whom are variable and should be re-understood.
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Objective@#To evaluate microstructural damage in high myopia (HM) patients using 3T diffusion kurtosis imaging (DKI). @*Materials and Methods@#This prospective study included 30 HM patients and 33 age- and sex-matched healthy controls (HCs) with DKI. Kurtosis parameters including kurtosis fractional anisotropy (FA), mean kurtosis (MK), axial kurtosis (AK), and radial kurtosis (RK) as well as diffusion metrics including FA, mean diffusivity, axial diffusivity (AD), and radial diffusivity derived from DKI were obtained. Group differences in these metrics were compared using tract-based spatial statistics. Partial correlation analysis was used to evaluate correlations between microstructural changes and disease duration. @*Results@#Compared to HCs, HM patients showed significantly reduced AK, RK, MK, and FA and significantly increased AD, predominately in the bilateral corticospinal tract, right inferior longitudinal fasciculus, superior longitudinal fasciculus, inferior fronto-occipital fasciculus, and left thalamus (all p < 0.05, threshold-free cluster enhancement corrected). In addition, DKI-derived kurtosis parameters (AK, RK, and MK) had negative correlations (r = -0.448 to -0.376, all p < 0.05) and diffusion parameter (AD) had positive correlations (r = 0.372 to 0.409, all p < 0.05) with disease duration. @*Conclusion@#HM patients showed microstructural alterations in the brain regions responsible for motor conduction and visionrelated functions. DKI is useful for detecting white matter abnormalities in HM patients, which might be helpful for exploring and monitoring the pathogenesis of the disease.
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Objective@#To evaluate microstructural damage in high myopia (HM) patients using 3T diffusion kurtosis imaging (DKI). @*Materials and Methods@#This prospective study included 30 HM patients and 33 age- and sex-matched healthy controls (HCs) with DKI. Kurtosis parameters including kurtosis fractional anisotropy (FA), mean kurtosis (MK), axial kurtosis (AK), and radial kurtosis (RK) as well as diffusion metrics including FA, mean diffusivity, axial diffusivity (AD), and radial diffusivity derived from DKI were obtained. Group differences in these metrics were compared using tract-based spatial statistics. Partial correlation analysis was used to evaluate correlations between microstructural changes and disease duration. @*Results@#Compared to HCs, HM patients showed significantly reduced AK, RK, MK, and FA and significantly increased AD, predominately in the bilateral corticospinal tract, right inferior longitudinal fasciculus, superior longitudinal fasciculus, inferior fronto-occipital fasciculus, and left thalamus (all p < 0.05, threshold-free cluster enhancement corrected). In addition, DKI-derived kurtosis parameters (AK, RK, and MK) had negative correlations (r = -0.448 to -0.376, all p < 0.05) and diffusion parameter (AD) had positive correlations (r = 0.372 to 0.409, all p < 0.05) with disease duration. @*Conclusion@#HM patients showed microstructural alterations in the brain regions responsible for motor conduction and visionrelated functions. DKI is useful for detecting white matter abnormalities in HM patients, which might be helpful for exploring and monitoring the pathogenesis of the disease.
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Objective:To explore the incidence and occurrence time of gallstone disease after bariatric surgery.Methods:Retrospectively analyzed the clinical data of 187 patients with morbid obesity who underwent bariatric surgery in the Department of General Surgery, Beijing Friendship Hospital, Capital Medical University from Dec. 2017 to Aug. 2019. All patients did not receive prophylactic ursodeoxycholic acid. All patients were underwent abdominal ultrasound and MRI examination preoperatively, and at least one abdominal ultrasound, MRI examination postoperatively. The incidence and occurrence time of gallstones and biliary sludge in patients with different bariatric surgery were analyzed respectively. Measurement data conforming to the normal distribution were described as mean ± standard deviation ( Mean± SD). Measurement data consistent with skewed distribution were described as median (lower quartile, upper quartile). Counting data were described as a percentage (%). Kruskal-Wallis test was used for comparison among groups, and then Bonferroni correction was used for pairwise comparison. Results:The follow-up time was up to Dec. 31, 2020, with a median follow-up time of 27.0 (22.0, 31.0) months. Thirty-four patients (18.2%, 34/187) developed gallstones after bariatric surgery. Individually, it was 18.0%(30/167) in LSG group, 22.2%(2/9) in LRYGB group, 11.1%(1/9) in LOAGB group and 50.0%(1/2) in LOAGB revisional surgery group. Eighteen patients (9.6%, 18/187) were found biliary sludge formation, among which 8.4% (14/167), 22.2% (2/9), and 22.2% (2/9) underwent LSG, LRYGB, and LOAGB, respectively. The rates of weight loss and BMI loss in patients with postoperative gallstone-formation were 21.4 (18.7, 23.6)% and 21.4 (18.6, 23.5) %, respectively. Three patients (1.6%, 3/187) had newly developed symptomatic gallstones, and all of them underwent LSG. The mean occurrence time for biliary sludge and gallstone was 85.5 (28.8, 98.8) and 103.5 (93.0, 179.3) days, respectively. Statistical difference in occurrence time was only found between postoperative gallstone and biliary sludge formation ( P=0.009). Conclusion:Without drug intervention, the incidence of gallstone after bariatric surgery was about 18.2% (34/187), which requires close clinical attention. Abdominal ultrasonography and the T2WI sequence of upper abdominal MRI can help to diagnose gallstone and monitor its changes.
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Objective:To verify the ability of the newly developed ultra-high resolution CT (U-HRCT) for displaying the fine bony anatomy of temporal bone.Methods:The cone-beam CT architecture was used on U-HRCT. The focus size of X-ray generator was 0.27 mm × 0.29 mm, the rated tube voltage was 60-100 kV, and the unit size of flat panel detector was 0.074 8 mm×0.074 8 mm. From October to December 2019, 16 adult head specimens (32 temporal bones, provided by Huanghe University of Science and Technology) were imaged using U-HRCT. The scanning mode was small-field-of-view and high-resolution scanning for unilateral temporal bone. The scanning parameters were: voltage 100 kV, current 3.5 mA, rotation time 40 s, reconstructed field of view 65 mm×65 mm, voxel size 0.1 mm×0.1 mm×0.1 mm, layer number 370, slice thickness 0.1 mm, and slice interval 0.1 mm. The ultimate spatial resolution of the system was detected using a phantom with line pair card, after the scanning with the same parameters. Through multi-planar reconstruction and minimum intensity projection method, a total of 6 anatomical positions of 4 structures (stapes footplate, cochlear axis bottom, vestibular aqueduct internal orifice and isthmus, cochlear aqueduct internal orifice and auditory sac segment) were scored with 1-3 points. The Wilcoxon test was used to compare the difference of bilateral scores of each structure.Results:The phantom test results showed that the ultimate spatial resolution of the system was ≥4.0 lp/mm. The scores of stapes footplate, cochlear axis bottom and vestibular aqueduct internal orifice were ≥2 points, with a display rate of 100%. The display rates of vestibular aqueduct isthmus, cochlear aqueduct internal orifice and auditory sac segment were 87.5% (28/32), 71.9% (23/32) and 53.1% (17/32), respectively. There were no significant differences in left and right scores of all anatomical structures ( P>0.05). Conclusion:The newly developed U-HRCT has good display ability for fine bony anatomy of temporal bone and has great clinical application potential.
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The German ( Kooperation für Transoarenz und Qualit?t im Gesundheitswesen, KTQ) certification system was officially launched in Germany in December 2001. Over ten years′ development proves that the KTQ certification system as a high standard medical management system. The authors introduced its background, the update of certification content and procedures, and explained its characteristics and advantages.These insights provide valuable references for establishing a professional and efficient quality certification system, suitable for China′s social and economic development level.
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Objective To investigate the value of high resolution CT (HRCT) in displaying the anatomic relationship between labyrinth segment of facial canal and cochlea.Methods Totally 110 patients (220 ears) who underwent HRCT were collected.The original images were transferred to workstation for image processing.MPR images were acquired.The anatomic relationship between labyrinth segment of facial canal and cochlea was observed in oblique coronal MPR images.The bony septum between labyrinth segment of facial canal and cochlea was assessed as definite defect (Type Ⅰ),doubtful defect (Type Ⅱ) or complete (Type Ⅲ),respectively.Results There were 71 ears (71/220,32.27％) of Type Ⅰ,diameters of bone fissure ranged from 0.3-1.3 mm (average diameters [0.64±0.26]mm),86 ears (86/220,39.09％) of Type Ⅱ and 63 ears (63/220,28.64％) of Type Ⅲ,with bony septum thickness ranged from 0.3-1.0 mm (average thickness [0.68±0.15]mm).No statistical difference of rates of the above three types was found between different genders,among age groups and between both side of ears (all P＞0.05).Conclusion HRCT is a reliable method to show the anatomic relationship between labyrinth segment of facial canal and cochlea.
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Objective To establish clinical quality control method with testing the birdcage head coils and setting up the action limits.Methods Three different MR devices (GE 1.5T HDi,GE 3.0T HD and GE 3.0T 750W) and corresponding birdcage coils were tested.Axial T1WI was performed to scan ACR phantom.SNR,percent image uniformity (PIU) and percent signal ghosting (PSG) were measured for six times,and the mean values and standard deviations (SD) were calculated.Based on the results,the action limits for each parameter were set.Results The mean value of SNR for the three devices was 262.14,280.47 and 474.24,and SD was 18.43,29.67 and 29.95,respectively;the action limits were ≥225.28,≥221.13 and ≥414.34,respectively;the mean value of PIU for the three devices was 95.00％,83.17％ and 84.33％,SD was 0.63％,1.17％ and 0.82％,respectively;the action limits were ≥93.74％,≥82.00％ (corrected) and ≥82.69％,respectively.The mean value of PSG for the three devices was 0.11％,0.07％ and 0.14％,SD was 0.12％,0.03％ and 0.11％,respectively;the action limits were ≤0.35％,≤0.13％ and ≤0.36％,respectively.Conclusion All of SNR,PIU and PSG for three MR devices were consistent with the action limits in this study.
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Objective To investigate the current status of overcrowding in emergency departments of Tertiary level A hospitals in order to discover and analyze key factors limiting the performance efficiency of staff to raise a suggestion of improvements.Methods The data regarding the distribution of the total number of available beds and total number of patients registered were collected from 19 tertiary level A hospitals to construct a regression model correlating variables including number of patients waiting,time of appointment and number of patients delivered by ambulances.The national grading system of crowdedness for emergency departments was used to estimate the NEDOCS_ BJ value for Beijing Friendship Hospital.Results Statistical analyses of key factors hampering the work efficiency and correlation between ESI triage and clinical decisions revealed overcrowding in the emergency department in a pattern across hospitals and time periods.The extent of overcrowding can be alleviated by way of increase in performance efficiency.Conclusions The proposed improvements regarding the hierarchical medical system,the development of treatment plans,and working procedure were recommended.
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Objective To observe the value of endovascular treatment of portal vein stenosis (PVS) after pediatric liver transplantation for biliary artesia.Methods The data of 14 children with PVS after liver transplantation for biliary atresia were retrospectively evaluated.All children were confirmed by portal vein angiography,and were treated with 1-2 times of percutaneous transluminal angioplasty with or without percutaneous transluminal stent angioplasty.The effect of endovascular interventional therapy in 14 children was analyzed.Results A total of 14 children received 23 times of endovascular interventional therapy.The technical success rate of the first treatment was 82.61％ (19/23).Ten children were treated with balloon dilatation,and stent angioplasty was performed in 4 children after balloon dilatation.These stents were not narrowed after implantation.There were no complications related to treatment in 14 cases.Conclusion Endovascular treatment for PVS after liver transplantation for biliary atresia is safe and effective.
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Objective To analyze the relationship between internal carotid artery (ICA) stenosis and ipsilateral retinal vascular calibers,and to investigate the feasibility and accuracy of changes of retinal vascular calibers for assessment of ICA stenosis.Methods Unilateral ICA and ipsilateral retinal vascular of 243 patients were enrolled based on CTA and fundus imaging.Patients were divided into 4 groups according to the highest ICA stenosis rate (Rmax),i.e.no stenosis group,mild stenosis group,moderate stenosis group and severe stenosis group.The differences of retinal vascular calibers among four groups and correlation between retinal vascular calibers and ICA stenosis were analyzed.Results The average central retinal vein equivalents (CRVE) in moderate ICA stenosis group and severe stenosis group were significantly wider than those in the other two groups (all P＜0.05).There was no statistical significance of central retinal artery equivalent (CRAE) nor retinal arteriolar-to-venular ratio (AVR) among groups (both P＞0.05).Rmax was positively correlated with CRVE (r=0.27,P＜0.01) and negatively correlated with AVR (r=-0.16,P＜0.05),whereas Rmax had no correlation with CRAE (P＞0.05).CRVE was the impact factor of ipsilateral Rmax (B=0.243,P＜0.01),but the adjusted R2 of the model was weak (0.173).Area under the ROC curve of CRVE was 0.619 in assessing ICA moderate and severe stenosis,and taking threshold as 229.5μm,the sensitivity and specificity was 80.3％ and 40.1％,respectively.Conclusion CRVE can assess and predict ICA stenosis to some extent,but the diagnosis efficacy is limited.
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Objective To test the central frequency (CF) and transmitter gain(TG) of MRI scanners,and set up their action limits.Methods Three different MRI devices (GE 3.0T HD,GE 1.5T HDi and GE 3.0T 750W) were tested by scanning American College of Radiology (ACR) phantom with the axial T1WI series.In the pre-scanning of T1WI series for the ACR phantom,the CF and TG were recorded.It was tested for eight times when MRI scanners were in good condition.The action limits of CF and TG were calculated based on mean values and standard deviations.Results The mean values of CF for three devices were (127 725 772.38±39.68)Hz,(63 875 740.13± 34.15)Hz,and (127 771 958.38±12.19)Hz,respectively.Their action limits were ≤119.04 Hz,≤68.30 Hz,and ≤36.57 Hz,respectively.The mean values of TG for three devices were (125.25±1.28)dB,(101.75±1.98)dB,and (113.25±0.89)dB,respectively.Their action limits were (125.25±2.56)dB,(101.75±3.96)dB,and (113.25±1.78)dB,respectively.Conclusion The CF and TG for three MRI scanners are all consistent with the action limits in this study.The CF and TG action limits will provide criterions for the clinical quality control.
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Objective To evaluate the value of percutaneous transhepatic angioplasty in treatment of portal vein stenosis (PVS) after pediatric liver transplantation.Methods The data of 8 pediatric patients with PVS after liver transplantation were retrospectively evaluated.All cases were confirmed by portal vein angiography,and were treated with percutaneous transluminal angioplasty and/or percutaneous transluminal stent angioplasty.The effect of endovascular interventional therapy in 8 cases was analyzed.Results A total of 12 times of 8 patients received endovascular interventional therapy.The success rate was 66.67％ (8/12).The clinical success rate of the first treatment was 62.50％ (5/8).Three cases were treated with balloon dilation after the first balloon dilation,and there was no recurrence of PVS after operation in 2 cases.After the treatment of balloon dilation,stent angioplasty was performed in 1 case.There were no complications related to treatment in 8 cases.Conclusion Endovascular interventional treatment is a safe and effective way for PVS after pediatric liver transplantation.
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Objective To evaluate the value of magnetic resonance thoracic ductography (MRTD)and magnetic resonance (MR) pelvic scanning in the chylous leakage of female reproductive system.Methods A retrospective evaluation of the imaging findings of MRTD and MR pelvic in 7 patients was performed,and compared with direct lymphangiography (DLG),lymphoscintigraphy and surgery.Results The rate of thoracic duct visualization in DLG was 71 .4% (5/7 ).The rate of venous angle visualization inlym-phoscintigraphy was 71.4% (5/7).The rate of thoracic duct visualization in MRTD was 100% (7/7).Except for 1 case withgeneral-ly normal findings,the remaining 6 cases showedobstruction of the thoracic duct in MRTD.Among those cases,bilateral drainage was found in 1 case,right thoracic ductwas seen in 1 case,multiple tortuous dilated lymphatic channelsaround the venous angle was detected in 4 cases,and multiple lymphangiomas was seen in 1 case.All of the 7 patients were conducted by surgery.6 cases were confirmed as obstruction of the thoracic duct.MRTD & MR pelvic found more multiple lymphangiomas lesions and detected 2 cases with bone abnormalities.Conclusion MRTD combined with MR pelvic could provide more comprehensive assessment of female re-productive system chylous leakage.It should be used as routine examination before operation.
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Objective To evaluate the effect of magnetic resonance thoracic ductography (MRTD)in the diagnosis of right thoracic duct.Methods MRTD data were analyzed retrospective,and the detection rate of right thoracic duct was summarized and compared with that of lymphoscintigraphy,direct lymphangiography and operation.Results 12 cases of right thoracic duct were detected in 1547 cases of MRTD.The detection rate was 0.78%,in which 1 case was complied with total internal organs inversion,and 1 case with right aortic arch.Lymphoscintigraphy were performed in all 12 cases and right thoracic duct were detected in 4 cases.Direct lymphangiography were performed in 4 cases and right thoracic duct were observed in all of them.7 cases of them received right lum-bar duct adhesiolysis.Conclusion MRTD is a noninvasive method for diagnosis of right thoracic duct,which providing useful guid-ance for surgical operation.Its detection rate and diagnostic accuracy are higher than those of lymphoscintigraphy.
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Objective To evaluate the value of MRI diagnosis in Stewart-Treves syndrome(STS).Methods The 48 STS nodules proved by pathology were retrospectively studied,which compared the MRI findings and pathological results.Results All nodules were solid and more than 4 mm in diameter.According to the expression of D2-40 and CD31,all nodules were divided into two types.The 47 nodules were divided into STS type I(hemangiosarcoma).The MRI findings showed slightly low signal on T1 WI and slightly high signal on T2 WI,while were higher than the muscular signal.Additionally,all nodules of STS type I were remarkably enhanced.The 1 mass-like-shape cases wsa divided into STS type Ⅱb (mixed lymphangiosarcoma).The MRI findings showed heterogeneous signal on both T1 WI and T2 WI,in which the high signal was leading.And the enhancement showed the low-level inhomogeneous signal.Conclusion MRI could be a valuable tool for the diagnosis in STS because of the characteristic signal on MRI.And if combined with the history of chronic upper limb lymphedema,the diagnostic accuracy could be improved before surgery.
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Clinical quality control of MRI equipment is a significant part of quality assurance.The purpose of quality control is to assure the performance and specification stability of MRI scanner,and to provide high quality images for clinical diagnosis.Many foreign countries have already developed and established highly sophisticated quality control procedure and regulation for MRI system,and the application is also relatively popular.However,this work has just begun in China,need to be further developed.The current status and future trend of clinical quality control procedure as well as regulation for MRI equipment were reviewed in this article.
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Objective To detect the cross-talk RF signal interference of three MRI scanners,in order to deepen the understanding of cross-talk RF signal interference.Methods Three different GE magnetic resonance imaging scanners (GE 1.5T HDi,installation time:2012;GE 3.0T HD,installation time:2006;GE 3.0T 750W,installation time:2016) were tested.The axial T1-weighted sequence was used to scan ACR phantom.Slice gaps with 5.0 mm,1.0 mm,0.5 mm and 0 were performed,respectively.SNR values were also recorded.Based on the results,the percentage change charts of SNR with slice gaps were made.Test standard was set as SNR decreased less than 20 ％ when the slice gap reduced from 5 mm to 0.Results When slice gap was reduced from 5 mm to 0,SNRs for three scanners decreased by 18.16 ％,23.57％ and 10.75％,respectively.Both the results of cross-talk obtained with GE 1.5T HDi and GE 3.0T 750W scanner met the test standard,while the result obtained with GE 3.0T HD (used for more than 10 years) was below the standard.Conclusion The cross-talk RF signal interference still exists for three MRI scanners.The test result of the scanner used for the longest time is unqualified.The quality control test of cross-talk should be done in the daily work.
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Objective To explore the evaluation methods of magnetic field uniformity and the practical operations,in order to provide references for clinical quality control.Methods Based on MRS phantom and 32 cm uniform spherical phantom,the evaluation methods of magnetic field uniformity were used to detect MRI equipment in department of radiology,including spectral peak and the bandwidth difference.Results The full width at half maximum (FWHM) of MRS phantom was 0.08 ppm,the inhomogeneity values on coronal,sagittal and axial detected by the bandwidth difference method was 0.15 ppm,0.08 ppm and 0.18 ppm,respectively.Conclusion The magnetic field homogeneity of the above mentioned MRI equipment is favorable,which accords with magnetic field uniformity detection standard.