Hilar cholangiocarcinoma (HCC) resection is a difficult and complicated surgery with high complication risk because of the special anatomic position.The detailed preoperative assessment is very important.Ultrasound (US), computed tomography (CT) and magnetic resonance imaging (MRI) can provide important information on the tumor location, vascular invasion and distant metastasis, which is necessary for the resection.Endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC) can be used to determine the tumor location and size, and achieve bile drainage.Magnetic resonance Cholangiopancreatolography (MRCP) as a noninvasive examination with fewer complications has comparable accuracy in identifying tumor extent with PTC and ERCP.The ultimate goal of surgical treatment is R0 resection.Preoperative resectablility evaluation mainly depends on the bile duct involvement, hilar vessels invasion, extent of hepatic lobe atrophy, lymphatic metastasis and nerve plexus infiltration.HCC radical resection often demands extended liver resection and accurate assessment of the residual liver function is very important for clinical strategy.Preoperative biliary drainage could be conducted in patients with cholangitis, long-term refractory jaundice (direct bilirubin level ＞ 200 μmol/L), poor nutrition status and residual liver volume ＜40％ of the total liver volume.Portal vein embolization decreases the long-term complications for HCC patients with enlarged liver resection.Portal vein embolization can be considered when residual liver volume ＜ 30％ ～40％.

Objective To study the safety and efficacy of surgical treatment for hilar cholangiocarcinoma (HC).Methods We retrospectively analyzed the clinical data of 56 patients with HC who underwent resection at the Beijing YouAn Hospital,Capital Medical University,from January 2010 to July 2015.The patients were divided into two groups according to the types of operations:the minor hepatectomy group (n =12) and the major hepatectomy group (n =44).The postoperative complications,mortality and long-term survival rates were compared and the clinical data were analyzed using uni-and multivariate analyses to examine the significant factors of survival.Results (1) The morbidity rates of the two groups were 33.3％ and 63.6％,respectively,with the latter group being significantly higher than the former group;(2) The 1-and 3-year overall survival rates were 60％ and 15％ in the minor liver resection group and 64％ and 15％ in the major resection group,and there was no significant difference between the two groups (P ＞ 0.05).The median survival was 16 months;(3) The median survival of R0 resection was significantly longer than the R1/R2 resection group (22 months vs 10 months,P ＜0.05);(4) Age,preoperative CA19-9 level,vascular invasion,surgical margin,tumor differentiation and nodular metastasis were significantly correlated with prognosis on univariate analysis.Multivariate analysis showed surgical margin and tumor differentiation to be significant prognostic factors.Conclusions RO resection obviously prolonged survival of HC patients,and histopathology negative surgical margin should be emphasized.With R0 resection,minor liver resection significantly reduced postoperative complications and mortality in selected patients.

Objective To compare the efficiency of computed radiography energy subtraction (ES-CR) with direct digital radiography (DR) in detecting the pulmonary soft-tissue signals.Methods The adult chest phantom including TRG was imaged by ES-CR and DR separately and was estimated by 6 radiologists with 5-value-differentiation method. ROC was used to analyze the performance of two systems. Images of DR and ES-CR of 28 patients with small lung cancer were diagnosed by 3 radiologists. Results The area under the ROC curves was 0. 727 in ES-CR and 0.827 in DR (Z= 2.96,P ＜ 0. 05). 28 small lung cancer patients were significantly different between two systems (x2 = 5.14,P ＜0. 05). Conclusions The true positive proportion of DR might be higher than that of ES-CR. ES-CR is inferior to DR in detecting pulmonary soft-tissue signals.

Objective To analyse the CT radiation dose statistically using the standardized radiation-dose-structured report (RDSR) of digital imaging and communications in medicine (DICOM). Methods Using the self-designed software, 1230 RDSR files about CT examination were obtained searching on the picture archiving and communication system ( PACS ) . The patient dose database was established by combination of the extracted relevant information with the scanned sites. The patients were divided into adult group (over 10 years) and child groups (0-1 year, 1-5 years, 5-10 years) according to the age. The average volume CT dose index ( CTDIvol ) and dose length product ( DLP) of all scans were recorded respectively, and then the effective dose ( E) was estimated. The DLP value at 75% quantile was calculated and compared with the diagnostic reference level ( DRL) . Results In adult group, CTDIvol and DLP values were moderately and positively correlated ( r=0?41 ) , the highest E was observed in upper abdominal enhanced scan, and the DLP value at 75% quantile was 60% higher than DRL. In child group, their CTDIvol in group of 5-10 years was greater than that in groups of 0-1 and 1-5 years ( t=2?42, 2?04, P<0?05);the DLP value was slightly and positively correlated with the age (r=0?16), while E was moderately and negatively correlated with the age ( r = -0?48 ) . Conclusions It is a simple and efficient method to use RDSR to obtain the radiation doses of patients. With the popularization of the new equipment and the application of regionalized medical platform, RDSR would become the main tool for the dosimetric level surveying and individual dose recording.

Objective To explore the value of the Accordion severity grading system (ASGS) in predicting short-term outcomes after orthotopic liver transplantation for severe hepatitis by classifying post-surgery complications.Methods The clinical documents of 159 patients were retrospectively analyzed who underwent orthotopic liver transplantation for severe hepatitis between Aug.1,2004 to Sept.1,2014 at our center.Complications were categorized according to the ASGS:grade 1 (mild),grade 2 (moderate),grade 3-5 (severe),and grade 6 (death).Outcome measures included ventilator support time,the length of ICU stay,postoperative recovery time.Spearman rank correlation analysis was used to test the correlation between the different grades with these outcome measures.1-year survival trends of different grade complication groups were demonstrated by Kaplan-Meier method and compared by Log-rank test.Results In total,43 (27.0％) patients had a grade 2 complication;41 (25.8％) grade 3;31 (19.5％) grade 4;9 (5.7％) grade 5;and 35 (22.0％) grade 6.There was no grade 1 patient.There was a significant correlation between the complication grades and the ventilator support time,the length of ICU stay and postoperative inpatient time (P＜0.01).With the increase of the complication grades,the outcome measures were even worse.Severe grade complication group had a longer ventilator support time,the length of ICU stay and postoperative inpatient time than the moderate grade complication group (P＜0.01).There was a significant downward trend in 1-year survival with the increase of the complication grade (P＜0.01).Conclusion The ASGS is helpful to assess risks and predict short-term outcomes after liver transplantation for severe hepatitis.Higher Accordion grades are correlated with even worse short-term outcomes.

Objective To identify the necessity to carry out optimization procedure in routine digital radiography (DR) by evaluating changes of patient radiation dose and image waste ratio before and after optimization.Methods Two hundred patients with near-standard body build were enrolled in the study.Half of them undertook routine examination,and the others undertook the examination with bestlyoptimized protocol.The dose-area product (DAP) and entrance surface dose (ESD) were recorded.The image waste ratios in 2 groups were calculated and the reasons for image waste were analyzed.The radiation dose and image waste ratio before and after optimization were compared.Results The ESD,DAP and image waste ratio in bestly-optimized radiography were significantly lower than those in non-optimized radiography (z =9.31,16.22,P＜0.05; x2 =36.5,P ＜ 0.05).Conclusion Using the bestlyoptimized digital radiography,the patient radiation dose and image waste ratio are effectively reduced.

Objective To perform thermoluminescent measurements of radial dose function and anisotropy function of a newly designed 192Ir microSelectron-HDR source, and establish evaluation methods for HDR dosimetry.Methods A polystyrene phantom with sylindrical holes in different measure positions was designed to accommodate thermo luminescent dosimeter (TLD) rods and radiation source.TLD rods with similar sensitivity were placed on a semicircle around the source center which had been precisely localized by either radiographic means or dose measurement.Dose-rates were measured at θ = 90° and r = 1-14 cm to calculate radial dose function (gL (r)), while measured along polar angles θ = 0° -165°(interval 15°) at radial distances r = 1 cm, 3 cm and 5 cm to calculate anisotropy function (F(r,θ)).All data were compared with those calculated by Monte Carlo (MC) method.The t-test was used for the statistics.Results The values of gL (r) were 1.007 -0.681 by calculation and 1.007 -0.598 by measurement with r = 1 - 14 cm(t = 0.00 - 2.89, all P > 0.05).The values of F (r,θ) were 0.631 - 1,0.660 - 1 and 0.696 - 1 by calculation, while 0.701 - 1, 0.668 - 1 and 0.629 - 1 by measurement at 1 cm, 3 cm and 5 cm with θ=0° -165°(t=0.40 -1.63, 0.02 -2.10, 0.08 -2.03, all P>0.05).Conclusions The results of radial dose function and anisotropy function measured by TLD measurement are in consistent with those calculated by MC calculations, which can be applied in treatment planning system as original input.

Objective To study the dosimetry parameters of 125I seed source (type Sinko BT-125-1) with thermoluminescent dosimeter (TLD) in the phantom.Methods The new type of phantom was modified to suit to measurement of a common type of 125I seed source.The AAPM TG43 protocol recommended measurements of dose-rate constant (Λ),radial dose function (gL (r)),and anisotropy function (F (r,θ)) have been performed in the phantom with TLD.Results The Λ was 0.928 cGyh-1 U-1.The gL(r) was determined at different radial distances r ranging from 1.0 to 10.0 cm with an interval of 1.0 cm ; and F (r,θ) at angles from 0° to 90° in 10° increments.The gL (r) of 125I seed source showed a difference of 9.6％ at the most in comparison to the corresponding values of 125I seed source (type Amersham 6711).The difference in F(2 cm,θ) of 125I seed source and Amersham 6711 was up to 10.2％ near the source end.With the phantom the combined standard uncertainty in the whole measurement was less than 6.0％.Conclusions The experimental results exhibit fairly small measurement uncertainties and good self-consistency.It's feasible to measure the dosimetry characters of permanent implant seeds in the modified phantom.

Objective To evaluate the parallactic unsharpness caused by flat panel detector in digital radiography using different incident angle of central ray. Methods R-1 square-wave phantom was exposed by Kodak DR3000 system with X-ray tube angled 0°, 10°, 20°, 30°, and 40° respectively. Then,presampled modulation transfer function (MTF) was calculated for each case above. Subsequently,experimental data were processed and Wilcoxon signed ranks test were performed by statistic software SPSS 10. 0, in which P ＜ 0. 05 was considered as statistically significant difference. Results The presampled MTF curves of incident angle of 0°-40° degree, were presented orderly from top to bottom, especially the incident angle of 40° was obviously the lowest. The incident angle of 0° was considered as a control group and other groups were compared against it. There was no statistically significant difference for MTF of incident angle of 10°( Z = - 1. 893 ,P = 0. 058 ), while there were significant difference for MTF of incident angle of 20°, 30°, and 40° ( Z = - 2. 547, - 2. 666, - 2. 666, P ＜ 0. 05 ). Conclusions For flat panel detector in digital radiography, the bigger the incident angle of central ray, the larger the parallactic unsharpness. In addition, this effect has less influence on structures of low spatial frequency than those of high spatial frequency.

Objective To test the overall characteristic curve on a computed radiography system. Methods Imaging plate was exposed by scale-time expose using conventional X-ray equipment. It was processed by CR system. Density of different optical density wedge on CR film was measured by using densimeter. Then, characteristic curve was plotted. Results (1) Overall characteristic curve of CR system was affected by gradation processing. (2) Average gradient of overall characteristic curve was 1.98, 3.10, and 3.75 when GA was 0.8,1.4, and 2.4. (3) Overall characteristic curve rotated around rotation center when rotation amount was changed. Conclusion According to the diagnostic purpose and different body position, rotation amount can be selected, and different contrast imaging can be acquired.