Objective To study the value of microwave coagulation therapy for liver malignant tumors.Methods Under local anesthesia,19 cases with hepatic malignant tumors treated with microwave knife under CT-guided.Results There were totally 23 tumors in 19 cases,13 tumors with≤3.5 cm in diameters were destroyed absolutely after the first treatmet,10 tumors among them were followed-up for 6-12 months and no recurred.10 tumors with＞3.5 cm in diameters treated at multiple points or angle,3～6 months later,CT showed that the tumors were destroyed completely in 6 and mostly in 4,by the hot condensate treatment secondly,3 tumors of 4 were destroyed completely 3 months later.There were no obvious complications.Conclusion The therapeutic effect under CT-guided microwave coagulation therapy for liver tumor which are ≤3.5 cm in diameter of the tumors is very reliable,the tumors＞3.5 cm in diameter can be destroyed mostly or completely by microwave treatment.

PurposeSupport vector machine (SVM) is a machine learning method based on statistical learning theory of Vapnik-Chervonenkis (VC) dimension structure and risk minimization theory. We analyzed the gem spectrum CT scan data of patients with thyroid nodules and established the SVM diagnostic model. The experimental targets were then reduced and the forecast analysis was carried out based on SVM model. The diagnostic model and experimental methods were proved to provide guidance for clinical diagnosis of thyroid nodules.

Objective:To investigate the immunohistochemical characterization of hepatic stem cells in the developing human liver, so as to study the origin, differentiation and migration of hepatic stem cells. Methods: H-E staining and immunohistochemical methods were used to observe the expression of hepatic/cholangiocellular differentiation markers (AFP,GST-?,CK7,CK19) and hematopoietic stem cell markers (CD34 and c-kit) in several kinds of cells obtained from thirty 4-to 35-week old fetal liver samples. Results: AFP expression appeared in fetal liver at 4 weeks’ gestation,peaked during 16-24 weeks’ gestation and decreased gradually afterwards; finally weak signals were only found in some ductal plate cells and a few limiting plate cells. GST-? was detected in hepatic cord cells from the 6th week and in the ductal plate cells from the 8th week; 26 weeks later, only some ductal plate cells and a few limiting plate cells showed positive signals. CK19 expression peaked during 6th to 11th week in hepatic cord cells and decreased gradually afterwards, except for that in the ductal plates. CK7 expression was limited in the ductal plate cells and bile duct cells from the 14th week. CD34 and c-kit were detected at the 8th week in some ductal plate cells and a few mononuclear cells in the hepatic cords/mesenchymal tissue of portal area; after 21 weeks, CD34 and c-kit were found only in ductal plate cells and a few mononuclear cells in the hepatic mesenchymal tissue of portal areas. Conclusion: Fetal hepatocytes at 4-16 weeks’ gestation are mainly constituted by hepatic stem cells with bi-potential differentiation capacity. At 16 weeks’ gestation, most hepatic cord cells begin to differentiate into hepatocytes and abundant hepatic stem cells remain in the ductal plate (the origin site of Hering canals). It is also indicated that the hematopoietic stem cells may give rise to some hepatic stem cells in embryonic liver. These indirectly support the hypothesis about the location and origin of liver stem cells in “liver valley hypothesis” reported previously.

Purpose To explore the value of spectral coronary CT angiography (CCTA) in reducing radiation dose and contrast dose using individualized optimal monochromatic imaging.Materials and Methods Sixty patients with suspected coronary disease were recruited in the study,who were randomly divided into two groups:group A (n=30) using conventional CT protocol with 350 mgI/ml contrast agent;group B (n=30) using low dose spectral CT imaging mode with 300 mgI/ml contrast agent.The images of group A were reconstructed with conventional process,and the images of group B were reconstructed with Optimal CNR to obtain the optimal monochromatic energy images.The images of both groups were transferred to an Advanced Workstation for analysis.Double-blinded method was carried out to qualify the images.CT values of coronary artery segments,as well as standard deviations (SD),the signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR) of aortic sinus were measured.Radiation doses and iodine intake were compared between the two groups.The optimal keV distribution in group B was analyzed.Results There was no significant difference for the subjective scoring of image quality,CT value of each coronary artery segment,SD,SNR,and CNR values between the two groups (P＞0.05).The effective radiation dose and total iodine load in group B were less than that in group A (P＜0.05).The optimal energy distribution for group B was 60-75 keV,average at (66.50+3.91) keV.Conclusion Compared with the conventional CT protocol,spectral CT imaging at optimal energy levels combined with iterative reconstruction can effectively reduce the radiation dose and iodine load,and obtain better images than usual protocol.

Objective To explore the value of the spectral CT iodine-based material decomposition technique in differential diagnosis of central pulmonary carcinoma from obstructive pneumonia and atelectasis.Methods 25 cases with central pulmonary carcinoma complicating with obstructive pneumonia and atelectasis underwent CT plain scan and spectral contrast scan including pulmonary-arterial-phase (PAP) and bronchial-arterial-phase(BAP).Conventional CT images and iodine base images were generated in each phase by GSI viewer.The 4 groups of images differences between the tumor and the obstructive pneumonia and atelectasis were analyzed.Results The margin of the tumor was ill-defined in plain scan.The cases that showed difference between the tumor and the obstructive pneumonia and atelectasis in 4 groups of images were respectively as follows,10 in conventional CT images of PAP,1 6 in conventional CT images of BAP,1 9 in iodine base images of PAP,and 23 in iodine base images of BAP.The difference of the 4 groups was significant (χ2 =16.54,P<0.05).There was the highest accuracy in iodine base images of BAP in defining the tumor margin (χ2 = 12.83,χ2 = 4.20,χ2 =1.34,P <0.05). The accuracy between conventional CT images of BAP and iodine base images of PAP had no significant differences (χ2 =0.86,P >0.05),but were better than that of the conventional CT images of PAP(χ2 =6.65,P <0.05).Conclusion Spectral CT iodine-based material decomposition technique is helpful to improve subjective diagnosis of central pulmonary carcinoma complicating with obstructive pneumonia and atelectasis,especially in iodine base images of BAP,it can provide accurate information for clinical stage and treatment.

Objective To discuss the methods and clinical effects of phased treatment of ankylosing spondylitis (AS) combined with severe hip flexion contracture.Methods The study enrolled 8 cases (12 hips) of AS combined with severe hip flexion contracture hospitalized from September 2011 to November 2012.Phased treatments included lateral hip arthrolysis,articular capsulectomy,stripping of the reflected head of rectus femoris,femoral neck osteotomy,traction and stage Ⅱ biotype total hip arthroplasty (THA).Preoperative and postoperative Harris score,hip range of motion,and complication of femoral nerve injury were detected.Results Period of follow-up was 6-12 months (mean 10 months).One case developed heterotopic ossification,which affected postoperative hip activity and received resection one year later.One case sustained fissure fracture of calcar femorale during implantation of the prosthetic femoral stem,but no special handling was provided.Of all cases,active flexion and extension of the hip were both 0° before operation,but increased to (96.25 ± 4.33) ° and (24.17 ± 4.69)° respectively after operation ; mean Harris score was improved from (26.67 ± 2.39) points preoperatively to (90.92 ± 5.66) points postoperatively (P ＜ 0.01).Besides,no femoral nerve injury was observed.Conclusion Phased treatment of AS combined with severe hip flexion contracture restores hip function and minimizes femoral nerve injury following THA.

Objective To compare the virtual non-enhanced chest CT (VNCT)generated from spectral CT with conventional non-enhanced chest CT in patients with lung disease in terms of CT number accuracy and image quality.Methods A total of 30 patients with lung disease proved by pathology underwent the conventional non-enhanced thoracic CT and contrast enhanced CT with spectral imaging mode in arterial phase (AP)and venous phase (VP).The VNCT images were reconstructed based on the enhanced spectral CT imaging data.The mean CT number,signal to noise ratio (SNR)for the lesions and image quality score were obtained and compared between the true non-contrast CT (TNCT)and the VNCT (including AP and VP)with paired t test.Results The mean±standard deviation for CT number were (38.74±5.17)HU,(39.08±5.07)HU and (38.96± 5.18)HU for TNCT,VNCT at AP and VNCT at VP,respectively, with no statistical difference (P>0.05).All 3 sets of images demonstrated acceptable image quality,even though there were statistically significant differences in the SNR value and image quality score.The mean ± standard deviation values for SNR were 4.74±0.42 with TNCT, 3.79 ± 0.5 1 with VNCT at AP and 3.77 ± 0.39 with VNCT at VP (P <0.05),and the image quality scores were 5.00 ±0.00 with TNCT,4.17±0.65 with VNCT at AP and 4.17±0.53 with VNCT at VP (P<0.05).Conclusion In patients with lung disease,the vir-tual non-enhanced CT images generated from spectral CT provide accurate CT numbers for lesions and acceptable image quality com-pared with the true non-contrast CT.VNCT may be used to replace TNCT to improve work flow and reduce radiation dose.

Objective To evaluate the post-operative glucose level and insulin dose of patients undergoing total pancreatectomy.Methods From September 1980 to September 2014, 21 patients underwent total pancrea-tectomy in Peking Union Medical College Hospital, who were enrolled in our study.We reviewed the changes in their insulin dosage and glucose levels after operation, also summarized type and dose of insulin as well as glucose level in stable period.Results The required insulin dose reached peak within 4 days after surgery ( maximum dose 300 U/d).The average dose was (143.5 ±62.8) U/d and decreased gradually.During the perioperative period (needing parenteral nutrition), the blood glucose level fluctuated markedly (1.52-29.06 mmol/L) and the average level was (11.18 ±0.95) mmol/L.During the stable period ( without parenteral nutrition) , patients on average had (5.3 ±2.0) U of preprandial rapid-acting insulin and (8.1 ±2.9) U of long-acting insulin be-fore sleeping;the average fasting blood glucose was (6.69 ±1.48) mmol/L, 2 h postprandial blood glucose was (9.08 ±2.84) mmol/L, bedtime blood glucose was (9.66 ±2.49) mmol/L, and blood glucose level at night was (8.15 ±2.78) mmol/L.67%of the patients had 13 hypoglycemic episodes monthly on average.For those five followed-up patients, the average hemoglobin A1c was (6.15 ±1.20)%.Conclusions Patients undergoing total pancreatectomy may experience marked fluctuation of blood glucose level and short-term increase of insulin need which gradually decreases afterwards.After entering the stable period, the glucose level could be well-con-trolled but with frequent hypoglycemia.There is no diabetic ketoacidosis.

Objective To demonstrate the feasibility of high-resolution computed tomography(HRCT)reconstructed with a model-based iterative reconstruction (MBIR)for evaluating early peripheral lung cancer (≤3 cm),by comparing image quality obtained from MBIR,filtered back proj ection reconstruction(FBP)and state of the art adaptive statistical iterative reconstruction(ASIR)algorithm respectively.Methods A total of 30 patients confirmed with lung cancer by postoperative pathology were enrolled in the study.A chest phantom was also used to evaluate image noise,spatial resolution and density resolution.Both patients and chest phantom were received HRCT,and the images were reconstructed using FBP,ASIR(40% ASIR and FBP mix)and MBIR.The objective CT value, standard deviation(SD)and signal noise ratio(SNR)were measured.Two radiologists used a semi-quantitative to rate subjective image quality of lung nodules.Results There was no significant difference in CT value between the three reconstruction algorithms (P>0.05).But significant improvements in objective image noise were observed in MBIR compared with FBP and ASIR (P<0.05):including the SD value in back muscle [(12.63±1.70)with MBIR vs (31.58±5.21)with FBP and (24.55±4.14)with ASIR],and in subcutaneous fat [(12.77±2.53)vs (24.39±5.08)and (19.20±4.11)].Subjective image noise of the three group were also significantly difference:FBP with lowest subjective noise score;and MBIR with highest subjective noise score.The sharpness of small vessels and bronchi and diagnostic acceptability with MBIR were significantly better than with FBP and ASIR (P< 0.05).Conclusion Lung HRCT reconstructed with MBIR provides diagnostically more acceptable images for the detailed analyses of peripheral lung cancer compared with FBP and ASIR.

Objective To compare the spatial resolution and density resolution balance algorithm(MBIRSTND)and spatial resolution preference algorithm (MBIRRP20)from new version of model-based iterative reconstruction(MBIRn),and adaptive statistical iterative reconstruction(ASIR) with lung kernel in routine dose about the performance of computer-aided detection (CAD)for quantitative analysis of airway.Methods 30 patients were involved who were scanned for pulmonary disease with spectrum CT.Data with a slice thinkness 0.625 mm were reconstructed with ASIR,MBIRSTNDand MBIRRP20.Airway dimensions from three reconstruction algorithm images were measured using an automated and quantitative software(Dexin-FACT)that was designed to segment and quantify the bronchial tree,and a skeletonization algorithm to extract the center-line of airway trees automatically.For each patient,reconstruction algorithm chose the right middle lobe bronchus,and the bronchial length of the matched airways was measured by this scheme.Two radiologists used a semiquantitative 5 scale (Score 0 stands for its image quality is similar to that with ASIR;Score±1 stand for a little better or a little worse;Score±2 stand for obviously better or obviously worse)to rate subjective image quality of airway trees about images reconstructed with MBIRSTNDand MBIRRP20.Paired t test and Wilcoxon signed-rank test were used.Results Algorithm impacts the measurement variability of bronchus length in chest CT.The bronchial length with MBIRRP20was longer than with MBIRSTND, while the length with ASIR were the shortest(P<0.05).In addition, the optimal reconstruction algorithm was found to affect the subjective noise,the continuity and completeness of bronchial wall,and the show of bronchial end.The subjective noise of MBIRSTNDwas better than that of MBIRRP20.The show of bronchial end of MBIRRP20was better than that of MBIRSTND(P<0.05).There was no significant difference in the continuity and completeness of bronchial wall compared with MBIRRP20and MBIRSTND(P>0.05),which was much better than with ASIR(P<0.05).Conclusion MBIRn can inmprove the analyzing ability of CAD airway.The MBIRSTNDcan significantly reduce the image noise,the MBIRRP20significantly improve the branching of the bronchial arteries,both of which can allow the desired airway quantification accuracy of CAD for chest CT of the bronchial wall.