To establish a medical imaging teacher competency model and evaluate its application value in group teaching for undergraduates.

The competency-based medical education has formed a global trend, and puts forward a greater challenge for educational design of resident training. The traditional curriculum cannot meet the goal of competency-based education as the curriculum design is lack of theoretical support. Curriculum design is the core of training content, and serves as a significant contributing factor of training outcome. Based on the six-step approach curriculum design, the theory and practice are integrated to form a curriculum design based on theoretical guidance. Through feedback evaluation, the current curriculum design is continuously improved in order to achieve a higher competency-based training quality. With the 5-year experiences and practice, preliminary reform demonstrates effectiveness. The current study hopes to share the teaching reform experiences of residency training base and provide references for colleagues of medical education.

Objective: To explore the application value of 3.0 T MultiVane XD (MVXD) technique in female patients with uterine adenomyosis and fibroids. Methods: Patients diagnosed with uterine fibroids with ultrasound and suspected of adenomyosis were involved prospectively from March to May 2018, 3.0 T pelvic MRI examinations were performed during peri-ovulatory period. Axialconventional turbo spin echo (TSE) T₂WI, axial MVXD T₂WI, sagittal conventional TSE T₂WI and MVXD sagittal T₂WI were acquired. Two observers rated those 4 series in the aspects of sharpness of uterine border, motion artifacts, identification capability of lesions, confidence of diagnosis and overall image quality. Cohen Kappa analysis was used to evaluate the consistency of scores between 2 observers. Scores of TSE T₂WI and MVXD T₂WI qualities were compared using Wilcoxon matched-pairs signed-ranks test. Results: Twenty patients were enrolled. Axial conventional TSE T₂WI, axial MVXD T₂WI were aquired on all of them. Sagittal conventional TSE T₂WI, sagittal MVXD T₂WI were aquired on 19 among them. Nine patients had only obvious adenomyosis, 6 had only uterinefibroids, and 5 had adenomyosis and uterine fibroids. Compared to conventional TSE technique, scores of two observers in the sharpness of uterine border, motion artifacts, and overall image quality is higher by MVXD with significant difference (P<0.05). The Kappa values for image quality scores of two observers ranged from 0.615 to 0.971, the agreement was good or very good. Conclusion Applying MVXD T₂WI technique to patients with uterine fibroids and adenomyosiscould improve image quality, without sacrificing the ability to recognize and diagnose lesions, compared to conventional TSE T₂WI technique.

Objective To evaluate the value of bone marrow imaging by third-generation dual-source dual-energy CT(DSDECT) using virtual noncalcium(VNCa) technique for the assessment of diffuse infiltrative lesions of multiple myeloma(MM). Methods From December 2015 to June 2016,31 patients with plasma disorders at our center were prospectively recruited and received whole-body imaging with third-generation DSDECT and MRI. CT numbers of vertebrae were measured on VNCa images as well as regular CT images. Correlation between VNCa CT numbers and MRI signal intensities of the vertebrae was evaluated. The diagnostic ability of VNCa for MM infiltrative lesions was assessed by ROC analysis,using MRI as the reference standard. Results The mean VNCa CT numbers of vertebrae with MM diffuse infiltration (n=62) were (-13.27±18.96)HU,which were significantly higher than those of non-infiltrated vertebrae[(-63.31±26.75)HU,(n=117)] (Z=-9.731,P=0.000). VNCa CT numbers of vertebrae were negatively correlated with T1WI signal intensity normalized by non-degenerative vertebral discs (r=-0.592,P=0.000). ROC analysis showed the area under the curve of VNCa for the diagnosis of infiltrative lesions was 0.943. With the cut-off value of-37 HU,the sensitivity and specificity of VNCa were 90.32% and 87.18%,respectively. Conclusion Bone marrow imaging by third-generation DSDECT using VNCa technique is a valuable tool for assessing diffuse infiltrative lesions of MM.
Bone Marrow ; diagnostic imaging ; Humans ; Magnetic Resonance Imaging ; Multiple Myeloma ; diagnostic imaging ; ROC Curve ; Sensitivity and Specificity ; Spine ; diagnostic imaging ; Tomography, X-Ray Computed ; methods

Objective To evaluate the feasibility of peripheral artery CT angiography (CTA)under 70 kV with 50 ml contrast medium on the third-generation dual-source CT. Methods Totally 82 patients who were equally randomized into two groups:70 kV group:the scan was performed under 70 kV tube voltage+50 ml iopromide on the third-generation dual-source CT;and 100 kV group:the scan was performed under 100 kV tube voltage+90 ml iopromide on the second-generation dual-source CT. The CT number of abdominal aorta,bilateral common iliac arteries,common femoral arteries,superficial femoral arteries,popliteal arteries and arteries of the calf were measured and contrast to noise ratio(CNR),signal to noise ratio(SNR)were calculated. The image quality was compared between these two groups. Results The dose-length product was (195.8±46.9)mGy·cm in 70 kV group,which was significantly lower than that in 100 kV group (461.6±57.9)mGy·cm,and was decreased by 57% (t=-22.848,P=0.000). Compared with the 100 kV group,the CT number of the proximal abdominal aorta in 70 kV group was significantly lower(t=-2.502,P=0.014),while the CT number of superficial femoral arteries (t=3.053,P=0.003)and popliteal arteries (t=4.013,P=0.000)was much higher in 70 kV group. SNR and CNR of proximal abdominal aorta,distal abdominal aorta,bilateral common iliac arteries,common femoral arteries,superficial femoral arteries,popliteal arteries and arteries of the calf were significantly lower in 70 kV group than those in 100 kV group (all P<0.05). The artifacts in abdominal aorta (t=2.893,P=0.000)and feet arteries (t=3.776,P=0.000)were higher in 70 kV group than those in 100 kV group,the enhancement of abdominal aorta (t=-1.000,P=0.002)and feet arteries (t=2.893,P=0.010)were lower in 70 kV group,the enhancement of femoral-popliteal arteries (t=-1.000,P=0.000)and arteries of calf (t=4.261,P=0.000)were higher in 70 kV group. Compared with the 100 kV group,the image noise in aorta (t=2.048,P=0.044),femoral-popliteal arteries (t=8.370,P=0.000),arteries of the calf (t=8.315,P=0.000)and feet arteries (t=7.202,P=0.000)were higher in 70 kV group. Conclusion Compared to conventional scan protocol,using 70 kV tube voltage with 50 ml contrast medium to perform peripheral artery CTA can assure the image quality and meanwhile remarkably reduce the radiation dose and the use of contrast medium.
Aorta, Abdominal ; diagnostic imaging ; Arteries ; diagnostic imaging ; Artifacts ; Computed Tomography Angiography ; Contrast Media ; Humans ; Iohexol ; analogs & derivatives ; Leg ; blood supply ; Radiation Dosage ; Signal-To-Noise Ratio ; Tomography, X-Ray Computed

Objective To investigate the feasibility of using low-dose prostate CT perfusion (pCTP)on a third-generation dual-source CT. Methods Nine patients with elevated prostate-specific antigen underwent pCTP before having prostate biopsy. We measured the blood flow (BF),blood volume (BV),mean transit time (MTT),permeability surface (PS),and time to peak(TTP)of both lesions and normal prostate tissue. The effective dose (ED)was calculated. Results Of the 9 cases,6 were prostate cancers and 3 were prostate hyperplasia with chronic inflammation. The average ED of the 9 pCTPs was (3.5±0.3)mSv. The BF (t=4.64,P<0.001),BV (t=3.27,P<0.001),and PS (t=3.58,P=0.004)of prostate cancer were significantly higher than those of normal prostate tissue and TTP (t=-1.26,P<0.001)of prostate cancer was significantly lower than that of normal prostate tissue. BF (t=3.96,P=0.001)and PS (t=2.91,P=0.021)of prostate hyperplasia with chronic inflammation were also significantly higher and TTP (t=-1.19,P<0.001)was significantly lower than those of normal prostate tissue. TTP of prostate cancer was significantly lower than that of prostate hyperplasia with chronic inflammation (t=-2.56,P=0.049). Conclusion sLow-dose pCTP is feasible on third-generation dual-source CT. The BF,PS,and TTP differ among prostate cancer,prostate hyperplasia with chronic inflammation,and normal prostate tissue.
Blood Volume ; Feasibility Studies ; Humans ; Male ; Prostatic Neoplasms ; diagnostic imaging ; Tomography, X-Ray Computed ; methods

Objective To evaluate the value of third-generation dual-source CT scanner in application of high-pitch aorta CT angiography(CTA). Methods Totally 59 patients clinically indicated for whole aorta angiography were divided into 2 groups using a simple random method:in group 1 there were 28 patients who underwent the examination on a third-generation dual-source CT device,with a collimation of 2×192×0.6 mm and a rotation time of 0.25 s;in group 2 there were 31 patients who underwent the examination on a second generation dual-source CT device,with a collimation of 2×128×0.6 mm and a rotation time of 0.28 s. Both groups were given the examination operated in dual-source high-pitch ECG-gating mode with a pitch of 3.0,a tube voltage of 100 kV,and automated tube current modulation using a reference tube current of 288 mA. A contrast material bolus of 45 ml with a flow of 4.5 ml/s followed by a 50 ml saline chaser in 5.0 ml/s was used. CTA scan was automatically started using a bolus tracking technique at the level of the original part of aorta after a trigger threshold of 100 HU was reached. The start delay was set to 6 s in both groups. Effective dose(ED),signal to noise ratio (SNR),contrast to noise ratio (CNR),and subjective diagnostic quality of both groups were evaluated. Results The mean ED were 19.44% lower (t=-3.989,P=0.000) in group 1 [(3.15±0.86)mSv] than in group 2 [(3.91±0.60)mSv]. These two groups showed no significant differences in SNR or CNR (all P >0.05). The subjective diagnostic quality values also showed no significant difference between two groups [(1.39±0.50)scores vs. (1.45±0.51)scores;W=814.5,P=0.651].Conclusion Compared with the second-generation dual-source CT scanner,the third-generation dual-source CT scanner in whole aorta CTA can remarkably reduce the radiation dose without affecting image quality.
Aorta ; diagnostic imaging ; Computed Tomography Angiography ; methods ; Humans ; Radiation Dosage ; Retrospective Studies ; Signal-To-Noise Ratio

Objective To evaluate the application of automated tube potential selection technique in high-pitch dual-source CT aortic angiography on a third-generation dual-source CT scanner. Methods Whole aorta angiography were indiated in 59 patients,who were divided into 2 groups using a simple random method:in group 1 there were 31 patients who underwent the examination with automated tube potential selection using a vascular setting with a preferred image quality of 288 mA/100 kV;in group 2 there were 28 patients who underwent the examination with a tube voltage of 100 kV and automated tube current modulation using a reference tube current of 288 mA. Both groups were scanned on a third generation dual-source CT device operated in dual-source high-pitch ECG-gating mode with a pitch of 3.0,collimation of 2×192×0.6 mm,and a rotation time of 0.25 s. Iterative reconstruction algorithm was used. For group 1,the volume and flow of contrast medium and chasing saline were adapted to the tube voltage. For group 2,a contrast material bolus of 45 ml with a flow of 4.5 ml/s followed by a 50 ml saline chaser at 5 ml/s was used. CTA scan was automatically started using a bolus tracking technique at the level of the original part of aorta after a trigger threshold of 100 HU was reached. The start delay was set to 6 s in both groups. Effective dose (ED),signal to noise ratio (SNR),contrast to noise ratio (CNR),and subjective diagnostic quality of both groups were evaluated. Results The mean ED were 21.3% lower (t=-3.099,P=0.000) in group 1 [(2.48±0.80) mSv] than in group 2 [(3.15±0.86) mSv]. Two groups showed no significant difference in attenuation,SD,SNR,or CNR at all evaluational parts of aorta (ascending aorta,aortic arch,diaphragmatic aorta,or iliac bifurcation)(all P>0.05). There was no significant difference in subjective diagnostic quality values of two groups [(1.41±0.50) scores vs. (1.39±0.50) scores;W=828.5,P=0.837]. Conclusion Compared with automated tube current modulation,the automated tube potential selection technique in aorta CT angiography on a third-generation dual-source CT can dramatically reduce radiation dose without affecting image quality.
Algorithms ; Aorta ; diagnostic imaging ; Computed Tomography Angiography ; methods ; Humans ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted ; Signal-To-Noise Ratio

Objective To evaluate the radiation dose and image quality of the third-generation dual-source CT using automated tube voltage adaptation (CARE kV) in temporal bone scanning in pediatric patients with hearing impairment. Methods Totally 27 children with hearing impairment less than 18 years old were randomly divided into two groups:Group A (n=14),examined with CARE kV (reference with 100 kV and 214 mA)and sinogram-affirmed iterative reconstruction;and Group B (n=13),examined with CARE kV (reference with 100 kV and 171 mA)and advanced modeled iterative reconstruction. The scan range was from eyebrow to the end of the mastoid process. CT values and image noise were measured.The signal to noise ratio (SNR)was calculated. Subjective image quality was assessed by two radiologists and later in a consensus reading. Results There was no significant difference in CT value,image noise,and SNR between these two groups (all P>0.05). Also,the subjective scores of the 10 anatomical structures showed no significant difference (all P>0.05). The CT dose index volume and dose-length product were (11.62+1.92)mGy and (106.92+37.48)mGy·cm,respectively,in group B and (21.28+2.19)mGy (t=12.15,P<0.001)and (229.65+56.26)mGy·cm (t=6.62,P<0.001)in group A,decreased by 45% and 53%. Conclusion Compared with the second-generation dual-source CT,the third-generation dual-source CT for the scanning of temporal bone with CARE kV can ensure image quality and reduce radiation dose.
Child ; Hearing Loss ; diagnosis ; Humans ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted ; Signal-To-Noise Ratio ; Temporal Bone ; diagnostic imaging ; Tomography, X-Ray Computed ; methods

Objective To investigate the image quality of head and neck CT angiography (CTA)using the third-generation dual-source CT combined with 70 kV tube voltage and 20-25 ml contrast medium (CM),and evaluate the effects of venous artifacts arising from the CM on the ipsilateral side of injection. Methods Totally 40 consecutive patients with suspected vascular diseases and body weight lower than 75 kg prospectively underwent head and neck CTA examination using the third-generation dual-source CT. CTA was performed with a third-generation dual-source CT system. Patients were randomly divived into 70 kV group (n=20)and 100 kV group (n=20). The 70 kV group used 20-25 ml CM and advanced modeled iterative reconstruction technique,and the 100 kV group used 40 ml CM and filtered back projection. Venous artifacts and CM residues were evaluated by a 3-point scale (1=excellent,3=poor),respectively. Results The effective dose of 70 kV group decreased 58% compared to 100 kV group (t=-18.14,P<0.001).In the 70 kV group,16 patients (80.0%)presented with venous artifacts and six of them (37.5%,6/16)affected the adjacent arteries. In the 100 kV group,19 patients (95.0%)presented with venous artifacts,and seven of them (36.8%,7/19)affected the adjacent arteries (Z=-0.878,P=0.380). In the 70 kV group,13 patients (65.0%)presented with obvious CM residues and two of them (15.3%,2/13)prolonged into the superior vena cava (SVC). In the 100 kV group,19 patients(95.0%)presented with obvious CM residues,and thirteen of them(68.4%,13/19)prolonged into the SVC (Z=-3.654,P<0.001). Conclusion Compared with the 100 kV,the third-generation dual-source CT for head and neck CTA,combined with 70 kV and 20-25 ml CM,can remarkably decrease the radiation dose,along with reduced CM residues and comparable venous artifacts.
Artifacts ; Body Weight ; Computed Tomography Angiography ; methods ; Contrast Media ; Head ; diagnostic imaging ; Humans ; Neck ; diagnostic imaging ; Radiation Dosage ; Radiographic Image Interpretation, Computer-Assisted