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Objective:To construct a machine-learning model for predicting the progression of pancreatic cystic lesions (PCLs) based on clinical and CT features, and to evaluate its predictive performance in internal/external testing cohorts.Methods:Baseline clinical and radiological data of 200 PCLs in 177 patients undergoing abdominal thin slice enhanced CT examination at Peking Union Medical College Hospital from July 2014 to December 2022 were retrospectively collected. PCLs were divided into progressive and non-progressive groups according to whether the signs indicated for surgery by the guidelines of the European study group on PCLs were present during three-year follow-up. 200 PCLs were randomly divided into training (150 PCLs) and internal testing cohorts (50 PCLs) at the ratio of 1∶3. 15 PCLs in 14 patients at Jinling Affiliated Hospital of Medical School of Nanjing University from October 2011 to May 2020 were enrolled as external testing cohort. The clinical and CT radiological features were recorded. Multiple feature selection methods and machine-learning models were implemented and combined to identify the optimal machine-learning model based on the 10-fold cross-validation method. Receiver operating characteristics (ROC) curve was drawn and area under curve (AUC) was calculated. The model with the highest AUC was determined as the optimal model. The optimal model's predictive performance was evaluated on testing cohort by calculating AUC, sensitivity, specificity and accuracy. Permutation importance was used to assess the importance of optimal model features. Calibration curves of the optimal model were established to evaluate the model's clinical applicability by Hosmer-Lemeshow test.Results:In training and internal testing cohorts, the progressive and non-progressive groups were significantly different on history of pancreatitis, lesions size, main pancreatic duct diameter and dilation, thick cyst wall, presence of septation and thick septation (all P value <0.05) In internal testing cohort, the two groups were significantly different on gender, lesion calcification and pancreatic atrophy (all P value <0.05). In external testing cohort, the two groups were significantly different on lesions size and pancreatic duct dilation (both P<0.05). The support vector machine (SVM) model based on five features selected by F test (lesion size, thick cyst wall, history of pancreatitis, main pancreatic duct diameter and dilation) achieved the highest AUC of 0.899 during cross-validation. SVM model for predicting the progression of PCLs demonstrated an AUC of 0.909, sensitivity of 82.4%, specificity of 72.7%, and accuracy of 76.0% in the internal testing cohort, and 0.944, 100%, 77.8%, and 86.7% in the external testing cohort. Calibration curved showed that the predicted probability by the model was comparable to the real progression of PCLs. Hosmer-Lemeshow goodness-of-fit test affirmed the model's consistency with actual PCLs progression in testing cohorts. Conclusions:The SVM model based on clinical and CT features can help doctors predict the PCLs progression within three-year follow-up, thus achieving efficient patient management and rational allocation of medical resource.
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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.
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Objective:To explore application value of improving quality of the low dose pancreatic CT images by using deep learning reconstruction (DLR).Methods:From August to December 2020, 68 patients who underwent contrast-enhanced pancreatic CT were prospectively collected in Peking Union Medical College Hospital. All patients were randomly divided into routine dose group (34 patients, with tube voltage of 120 kV) and low dose group (34 patients, with tube voltage of 100 kV). All patients underwent non-contrast, arterial phase, parenchymal phase and delay phase scans. The four-phase images of low dose group were reconstructed by using filtered back projection (FBP), hybrid iterative reconstruction (AIDR) and DLR which were marked with LD-FBP, LD-AIDR and LD-DLR, respectively. The four-phase images of routine dose group were reconstructed by using AIDR algorithm which were marked with RD-AIDR. The CT value, image noise (SD), signal to noise ratio (SNR) and contrast to noise ratio (CNR) of pancreas were measured. The ANOVA test was performed in comparison with objective parameters of different reconstruction algorithms, and LSD test was performed in pairwise comparison. The subjective image scores were obtained and were compared using Kruskal-Wallis test.Results:CT value, SD, SNR and CNR of non-contrast, arterial phase, parenchymal phase and delay phase had significant difference among different reconstruction images of routine dose group and low dose group (all P<0.05). The CT value of LD-FBP, LD-AIDR, and LD-DLR images were significantly higher than those of RD-AIDR images in parenchymal phase and delay phase (all P<0.05). There were statistically significant differences in each pairwise comparison of SD and SNR of four phase images (all P<0.05). There were statistically significant differences of CNR among LD-FBP, LD-DLR and RD-AIDR in four phase images (all P<0.05). The CNR of RD-AIDR was better than that of LD-FBP, and CNR of LD-DLR was better than that of RD-AIDR. DLR algorithm improved the SD, SNR and CNR of four phases of pancreatic images. The improvement of SNR was more significant after contrast enhancement, and the improvement of CNR was more significant in the non-contrast and delay phases. Subjective image scores of different reconstruction images were statistically different in four phase images (all P<0.001). Overall image scores of LD-DLR and RD-AIDR had no significant differences in four phase ( Z value of four phases were 1.00, 2.24, 0.45 and 1.34, respectively; P value of four phases were 0.317, 0.025, 0.655 and 0.180, respectively). Conclusion:The DLR technology can decrease radiation dose of pancreatic CT, improve image quality and satisfy diagnostic requirement. The DLR technology can also reduce image noise, improve the SNR and CNR in low dose contrast-enhanced pancreatic CT.
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Objective:To investigate the correlation between amide proton transfer-weighted (APTw) values and Ki-67 labeling index of cervical squamous cell carcinoma.Methods:From October 2017 to December 2018, 24 patients with cervical squamous cell carcinoma [International Federation of Gynecology and Obstetrics (FIGO) stage Ⅰ-Ⅲ] were prospectively enrolled in Peking Union Medical College Hospital and underwent pelvic morphological MRI on a 3.0 T MR scanner, including three-dimensional turbo-spin-echo APTw imaging and DWI. The maximum diameters of the lesions, APTw values and ADC values on the slice with the maximum diameter of the lesion were independently measured by two radiologists. The ICC was computed to evaluate the inter-observer consistency. Ki-67 immunohistochemical expression status was assessed by one pathologist. The Pearson correlation analysis was performed between the APTw values, maximum diameters, ADC values and Ki-67 labeling index.Results:The APTw values of cervical squamous cell carcinoma were (2.9±0.5)%. Inter-observer ICC was 0.972 (95%CI 0.937-0.988). The APTw values were positively moderately correlated with Ki-67 labeling index [(61.9±18.7)%, r=0.532, P=0.008]. The maximum diameters of the lesions were (28.7±10.6) mm. The mean ADC values were (0.998±0.217)×10 -3 mm 2/s. No correlations were found between maximum diameters, ADC values and Ki-67 labeling index ( r=0.038, P=0.859; r=0.238, P=0.263). Conclusion:APTw values can partially reveal the proliferation status of cervical squamous cell carcinoma.
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Pancreatic neuroendocrine neoplasms (pNENs) are highly heterogeneous, and the management of pNENs patients can be intractable. To address this challenge, an expert committee was established on behalf of the Chinese Pancreatic Surgery Association, Chinese Society of Surgery, Chinese Medical Association, which consisted of surgical oncologists, gastroenterologists, medical oncologists, endocrinologists, radiologists, pathologists, and nuclear medicine specialists. By reviewing the important issues regarding the diagnosis and treatment of pNENs, the committee concluded evidence-based statements and recommendations in this article, in order to further improve the management of pNENs patients in China.
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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.
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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) T 2WI, axial MVXD T 2WI, sagittal conventional TSE T 2WI and MVXD sagittal T 2WI 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 T 2WI and MVXD T 2WI qualities were compared using Wilcoxon matched-pairs signed-ranks test. Results:Twenty patients were enrolled. Axial conventional TSE T 2WI, axial MVXD T 2WI were aquired on all of them. Sagittal conventional TSE T 2WI, sagittal MVXD T 2WI 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 T 2WI technique to patients with uterine fibroids and adenomyosiscould improve image quality, without sacrificing the ability to recognize and diagnose lesions, compared to conventional TSE T 2WI technique.
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Objectives: This randomized, controlled clinical trial aims to compare the efficacy and safety of glucocorticoid combined with MMF and glucocorticoid monotherapy for patients with IgG4-related disease. Methods: Sixty-nine patients newly diagnosed with IgG4-related disease were randomly divided into two groups (35 patients in Group I and 34 patients in Group II). Patients in Group I received glucocorticoid monotherapy (0.6-0.8 mg/(kg·day) and tapered gradually); patients in Group II received glucocorticoid combined with MMF therapy (1-1.5 g/day). All the patients were followed up at 1, 3, 6 and 12 months. The primary endpoint was response rate in 12 months and the secondary endpoints were relapse, remission rate and adverse reactions. Results: Group I and Group II shared almost the same efficacy at the 1 month treatment, but during the follow-up, the complete response rate in Group II was much higher than that in Group I at different time points, and the cumulative relapse rate during 1 year of therapy was much higher in Group I than that in Group II (40.00 vs 20.59%). The remission rate was lower in Group I (51.42 vs 76.47%). Relapses were more likely to happen in lung, lacrimal gland, salivary gland, paranasal sinus and kidney. MMF could reduce relapse, especially organs recurrence. No serious adverse reactions occurred in the two groups. Conclusion: Combination treatment with glucocorticoid and MMF was more effective than the monotherapy, and the relapse of IgG4-related disease might be associated with the elevated levels of serum IgG4 and the low glucocorticoid maintenance dose. Trial registration: ClinicalTrials.gov, www.clinicaltrials.gov, NCT02458196.
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Glucocorticoids/administration & dosage , Immunoglobulin G4-Related Disease/drug therapy , Immunosuppressive Agents/administration & dosage , Mycophenolic Acid/administration & dosage , Adult , Aged , Drug Therapy, Combination , Female , Humans , Induction Chemotherapy , Male , Middle Aged , Prospective Studies , Treatment OutcomeABSTRACT
Objective To analyze the imaging data of patients with complete clinical remission ( cCR ) and postoperative pathological complete remission ( pCR ) after concurrent chemoradiotherapy, aiming to evaluate the values of MRI and rectal ultrasound in predicting pCR. Methods Clinical data of 42 patients with locally advanced rectal cancer treated with concurrent chemoradiotherapy combined with operation were retrospectively analyzed. The magnetic resonance imaging (MRI), endoscopic ultrasound (EUS) and pathological data were statistically compared between patients with cCR and pCR. Results After concurrent chemoradiotherapy,12 patients obtained cCR and 7 patients achieved pCR.The consistency rate of cCR between MRI and EUS was 3/12(25%), and 4/12(33%) for pCR.The consistency rate of pCR of MRI combined with EUS was 5/12 ( 42%) . Conclusion Rectal ultrasound combined with MRI cannot fully predict pCR. More accurate detection approach remains to be explored to evaluate the clinical outcomes of watch-and-wait patients.
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This is a complicated and difficult case. The onset symptom of a 62-year-old male was recurrent intestinal obstruction. Ileocecal and ileocolic operation was done twice. Massive gastrointestinal bleeding occurred due to giant fistula of descending duodenum, which connected to ileocolic anastomosis. After consultation by multidisciplinary team, jejunal-feeding tube was placed to provide enteral nutrition. With general condition improving, duodenal fistula repair and involved bowel resection were performed. Postoperative pathology confirmed Crohn's disease. The patient was treated with thalidomide and recovered well during follow-up.
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Objective To evaluate the effects of infective necrosis (IN) on prognosis in moderately severe or severe acute pancreatitis (AP).Methods According to the revision of Atlanta classification,from January 2001 to January 2015,admitted patients with moderately severe or severe AP were retrospectively analyzed.According to whether with the presence of persistent organ failure (POF) and / or IN,the patients were divided into four groups:group one with weither IN nor POF,group two with IN but without POF,group three with POF but without IN,group four with both IN and POF.The differences in disease severity and prognosis among groups were compared.Logistic regression and Cox proportional hazard regression model were used to analyze the effect of IN on prognosis.Results A total of 375 moderately severe or severe AP patients were enrolled.There were 211,43,90 and 31 patients in group one,two,three and four,respectively.A total of 121 (32.3%) patients with POF,74 (19.7%) patients with IN,and death in 63 (16.8%) patients.The mortality rate in patients with IN was 32.4% (24/74),and which was 13.0%(39/301) in patients without IN.The mortality rates of group one,two,three and four were 1.9%(4/211),11.6%(5/43),38.9%(35/90) and 61.3%(19/31),respectively;mortality rate was in a trend of increasing,and the difference was statistically significant (x2 =109.672,P<0.01).Both IN (OR=8.24,95%CI2.09 to 32.46) andPOF (OR=8.31,95% CI2.48 to 27.87)were independent risk factors of mortality of AP patients (both P<0.01).Both IN (OR=2.04,95 %CI 1.19 to 3.48,0.002) and POF (OR=5.25,95%CI 2.36 to 11.65) also were independent risk factors of shortened survival time of AP patients (both P<0.01).Conclusions IN is an independent risk factor of disease severity and poor prognosis in AP.The prognosis is the worst in AP patients with both POF and IN.
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Objective To investigate the feasibility of using CT texture analysis to differentiate among lipid-poor adrenal adenoma,pheochromocytoma and adrenal metastases.Methods 66 lipid-poor adrenal adenoma,98 pheochromocytoma and 101 adrenal metastases lesions were analyzed retrospectively.All the patients had abdominal non-enhanced CT and adrenal enhanced CT scans.We used TexRAD software to analyze the textural features of CT images and compared the differences in each texture parameter among three adrenal lesions.Results On non-enhanced CT images,there were significant differences in Mean and Kurtosis at all the texture scales(SSF 0-6) among the three types of adrenal lesions (P<0.05),as well as SD at fine and coarse texture scale (SSF 2,6)(P<0.05).Entropy (SSF 0-3, 5-6) and MPP (SSF 0-2, 4-6) were significantly lower in lipid-poor adrenal adenoma and adrenal metastases than that in pheochromocytoma (P<0.05).There were significant differences in Skewness (SSF 0-3) among three types of lesions, which was lowest in pheochromocytoma and highest in adrenal metastases.On enhanced CT images, Mean, SD, Entrophy and MPP showed significantly differences among the three types of adrenal lesions at all the texture scales (SSF 0-6) (P<0.05), which were all highest in pheochromocytoma and lowest in adrenal metastases.Skewness (SSF 0) and Kurtosis (SSF 0, 2) were significantly lower in adrenal metastases than that in lipid-poor adrenal adenoma and pheochromocytoma (P<0.05).Conclusion There are significant differences in CT texture analysis parameters among lipid-poor adrenal adenoma,pheochromocytoma and adrenal metastases.CT texture analysis has potential clinical application values in differentiating these three adrenal lesions.
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Objective To analyze the clinical characteristics of IgG4-related disease (IgG4-RD)so as to improve the understanding of IgG4-RD in China.Methods IgG4-RD patients were recruited from Peking Union Medical College Hospital between January 2011 and January 2016.All patients were followedup for more than 6 months.The demographic characteristics,symptoms,organ involvements,laboratory examinations and treatment efficacy were evaluated and analyzed.Results A total of 346 patients were finally enrolled,including 230 males (66.5%) and 116 females (33.5%).The mean age of disease onset was (53.8 ± 14.2) years old.The mostly common involved organs were lymph nodes (56.4%) and submandibular glands (52.6%).Other affected organs and manifestations included:swelling of the lacrimal glands (46.5%),autoimmune pancreatitis (38.4%),pulmonary involvement (28.0%),sclerosing cholangitis (25.4%),naso-sinusitis (23.4%),parotid gland swelling (21.7%),retroperitoneal fibrosis (19.9%),large arteries involvement (9.5%),kidney involvement (obstructive nephropathy caused by retroperitoneal fibrosis was excluded) (6.9%),skin lesions (6.4%).Rare features consisted of thyroid glands,pituitary glands,gastrointestinal tract,pachymeningitis,pericardium,sclerosing mediastinitis and orchitis.The majority of patients had multi-organ involvement,such as 74.3% patients with 3 and more,18.2% and 7.5% patients with 2 and single organ involvement respectively.The average IgG4-RD responder index (IgG4-RD RI) was 13.21 ±5.70.History of allergy was found in 172 (49.7%) patients.As to the laboratory tests,elevated serum IgG4 levels were confirmed in 285 (94.1%) patients,which was positively correlated with IgG4-RD RI.There were 33.5% patients receiving monotherapy of glucocorticoid,52.6% treated with glucocorticoids combined with immunosuppressive agents,4.9% patients with immunosuppressant only,and 9.0% patients with mild disease not receiving medication.The majority (336,97.1%) patients improved the above regimens.Conclusion IgG4-RD is a systemic fibro-inflammatory disease with multiple organ involvement.The mostly common involved organs include lymph node,submandibular glands,and pancreas.Glucocorticoids and immunosuppressive agents were effective for IgG4-RD.
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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.
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Humans , Bone Marrow , Diagnostic Imaging , Magnetic Resonance Imaging , Multiple Myeloma , Diagnostic Imaging , ROC Curve , Sensitivity and Specificity , Spine , Diagnostic Imaging , Tomography, X-Ray Computed , MethodsABSTRACT
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.
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Humans , Aorta, Abdominal , Diagnostic Imaging , Arteries , Diagnostic Imaging , Artifacts , Computed Tomography Angiography , Contrast Media , Iohexol , Leg , Radiation Dosage , Signal-To-Noise Ratio , Tomography, X-Ray ComputedABSTRACT
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.
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Humans , Male , Blood Volume , Feasibility Studies , Prostatic Neoplasms , Diagnostic Imaging , Tomography, X-Ray Computed , MethodsABSTRACT
Objective To explore the feasibility of reducing radiation dose of CT colonography (CTC) while preserving image quality using the third-generation dual-source CT at 70 kV tube voltage with advanced modeled iterative reconstruction (ADMIRE). Methods This prospective study consecutively included 53 patients. All patients underwent CTC at 120 kV in supine position with filtered back projection reconstruction and at 70 kV in prone position with ADMIRE with the same scan range. Radiation dose and image quality were compared between these two protocols. Results CT dose index volume,dose-length product,and effective dose of 70 kV were (1.47±0.23)mGy,(68.85±13.82)mGy·cm,and (1.03±0.21)mSv,respectively,which were significantly lower than 120 kV mode [(2.96±0.61)mGy (t=25.356,P=0.000),(136.97±32.77)mGy·cm (t=22.246,P=0.000),and (2.05±0.49)mSv (t=22.293,P=0.000)]. Signal to noise ratio of 70 kV with ADMIRE was 3.60±0.58,which was obviously higher than that of 120 kV as 2.34±0.47 (t=-18.036,P=0.000). Noise of 70 kV with ADMIRE was (11.81±1.93)HU,which was obviously lower than that of 120 kV as (14.39±2.57)HU (t=7.856,P=0.000). The κ value of two radiologists' overall subjective image score was 0.843 (P=0.000). For 2D images,the noise score of 70 kV with ADMIRE was significantly lower (Z=325.000,P=0.000) and the overall image quality was significantly higher (Z=78.000,P=0.001) compared with 120 kV;however,the sharpness had no significant difference. All scores ranged from 4 to 5. For 3D virtual endoscopy,the overall image quality of 70 kV with ADMIRE and 120 kV was not significantly different (Z=4.000,P=0.059),and all scores ranged from 4 to 5. Conclusion CTC at 70 kV tube voltage combined with ADMIRE can remarkably reduce the radiation dose while maintaining imaging quality than 120 kV at third-generation dual-source CT.
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Humans , Colon , Diagnostic Imaging , Colonography, Computed Tomographic , Methods , Prone Position , Prospective Studies , Radiation Dosage , Radiographic Image Interpretation, Computer-Assisted , Radionuclide Imaging , Signal-To-Noise RatioABSTRACT
Objective To evaluate the image quality and radiation exposure in multidetector computed tomography (MDCT) with automated topogram-based tube potential selection,compared to fixed tube potential,in patients with solid pancreatic lesions. Methods The preoperative pancreatic dual-source CT images of 113 patients who were confirmed as solid pancreatic lesions by postoperative pathology in the Peking Union Medical College Hospital from January 2014 to August 2016 were retrospectively analyzed.Among them,53 patients were examined on fixed tube potential at 120 kV,and tube current was automatically modulated (group 1). Sixty patients underwent topogram-based automatic tube potential selection (Tube voltage step:90,100 kV) and automated mA modulation (group 2). Two experienced radiologists measured the body sizes,assessed subjective and objective image quality of arterial phase and portal phase,and recorded radiation parameters including CT dose index volume (CTDI) and dose-length product (DLP). Results Of 60 patients in group 2,45 patients were scaned at 90 kV,15 patients were scaned at 100 kV.The average body diameter [(287±24) mm] in 90 kV group was significantly lower than that [(328±22) mm] in 100 kV group(t=0.731,P=0.0008). The mean CTDI[(3.9±1.0) mGy] in group 2 was significantly lower than in group 1 [(9.0±1.9) mGy],reduced by 56.7% (t=17.5,P=0.0003). The average DLP [(109±38) mGy·cm] in group 2 was significantly lower than that in group 1 [(276±83) mGy·cm],reduced by 60.5% (t=14.0,P=0.0007). In group 2,the standard deviations of images background noise in arterial and portal phase were (6.4±0.9) and (6.4±1.0)HU,respectively,which were significantly higher than those in group 1 [(5.6±1.4)HU,t=-3.757,P=0.0003;(5.5±1.4)HU,t=-3.828,P=0.0006]. In group 2,the signal to noise ratios of pancreatic lesions, abdominal aorta in arterial phase and pancreatic lesions, the portal vein in portal phase were 18.8±9.3,76.0±19.3 and 17.4±6.7,33.1±7.2,which were significantly higher than those in group 1 (13.1±8.7,t=-3.379,P=0.001;56.5±22.6,t=-2.268,P=0.025;14.1±8.1,t=-2.283,P=0.024;28.9±8.8,t=-2.613,P=0.009). Conclusion Compared with fixed tube voltage on the second-generation dual-source CT techniques,topogram-based automatic tube potential selection on third-generation dual-source CT can reduce radiation dose without decreasing image quality in imaging solid pancreatic lesions.
Subject(s)
Humans , Multidetector Computed Tomography , Methods , Pancreas , Diagnostic Imaging , Pathology , Radiation Dosage , Retrospective Studies , Signal-To-Noise RatioABSTRACT
Objective To characterize the CT perfusion parameters of focal pancreatic lesions including pancreatic cancers (PACs) and pancreatic neuroendocrine tumors (pNETs),estimate the confirmity and fungibility of parameters obtained from Deconvolution and Maximum slope+Patlak.Methods From December 2015 to November 2016,22 patients with PACs and 22 patients with pNETs(37 lesions confirmed by surgery and biopsy)underwent preoperative whole-pancreas CT perfusion in our center. The volume perfusion CT of the entire pancreas was performed at 80 kV and 100 mA,using 28 consecutive volume measurements and intravenous injection of 45 ml of iodinated contrast and saline at a flow rate of 5 ml/s. One experienced radiologists measured and recorded the CT perfusion parameters on Siemens post-processing workstation using two mathematical methods:Maximum slope+Patlak analysis versus Deconvolution method.ResultsWilcoxon matched-pairs test revealed significant difference between both pairs of the perfusion measurements by the two methods,PACs(BFM vs. BFD,Z=-3.263,P=0.001;BVD vs. BVP,Z=-3.978,P=0.000); pNETs(BFM vs. BFD,Z=-5.212,P=0.000;BVD vs. BVP,Z=-2.633,P=0.008). Spearman's correlation coefficient showed both pairs of perfusion measurements significantly correlated with each other in PACs (BFM vs. BFD,r=0.845,P=0.000;BVD vs. BVP,r=0.964,P=0.000) and pNETs(BFM vs. BFD,r=0.759,P=0.000),BVD vs. BVP,r=0.683,P=0.000). Geometric mean BFM/BFD ratio in PACs was 0.77 (range:0.61-0.99),while geometric mean BVD/BVP ratio was 1.42 (range:1.13-1.79),within 95% limits of agreement. Geometric mean BFM/BFD ratio in pNETs was 0.66 (range:0.51-0.86),while geometric mean BVD/BVP ratio was 1.15 (range:0.88-1.50),within 95% limits of agreement. Conclusion sSignificantly different CT perfusion values of blood flow and blood volume were obtained by Deconvolution-based and Maximum slope+Patlak-based algorithms in the pNETs and PACs. They correlated significantly with each other. Two perfusion-measuring algorithms are interchangeable because the ranges of the conversion factors are narrow.
Subject(s)
Humans , Algorithms , Blood Volume , Contrast Media , Pancreas , Diagnostic Imaging , Pathology , Pancreatic Neoplasms , Diagnostic Imaging , Reproducibility of Results , Sensitivity and Specificity , Tomography, X-Ray Computed , MethodsABSTRACT
Objective To compare measurements of dual-energy CT iodine map parameters and liver perfusion CT parameters in patients with focal liver lesions using a third-generation dual-source CT scanner. Methods Between November 2015 and August 2016,33 patients with non-cystic focal lesions of liver were enrolled in this study. CT examinations were performed with a third-generation dual-source CT. The study CT protocol included a perfusion CT and dual-energy arterial and portal venous scans,with a time interval of 15 minutes. Iodine attenuation was measured at five region of interests including areas of high,medium,and low density within the lesion,as well as right and left liver parenchyma from the iodine map,while arterial liver perfusion (ALP),portal venous liver perfusion (PVP),and hepatic perfusion index (HPI) at the same location were measured from perfusion CT. The Pearson product-moment correlation coefficient was used to evaluate the relationship between iodine attenuation and perfusion parameters. Results The iodine attenuation at arterial phase showed significant intra-individual correlation with ALP (r=0.812,95% CI=0.728-0.885,P<0.001)and PVP (r=-0.209,95% CI=-0.323--0.073,P=0.007),but not significantly correlated with HPI (r=0.058,95% CI=0.046-0.498,P=0.461). The iodine attenuation at portal venous phase showed significant correlation with PVP (r=0.214,95% CI=0.072-0.361,P=0.005) but not with HPI(r=0.036,95% CI=-0.002-0.242,P=0.649). The mean effective dose of arterial phase and portal venous phase of dual-energy CT together [(3.53±1.17)mSv] was significantly lower than that of the perfusion CT [(14.53±0.45)mSv](t=25.212,P<0.001). Conclusion Iodine attenuation from arterial phase of dual energy CT demonstrates significant correlation with ALP and PVP,and iodine attenuation from portal venous phase demonstrates significant correlation with PVP.