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Objective To study the value of dual energy cerebral arteries computed tomographic angiography (CTA) in diagnosis of cerebral aneurysm.Methods As a gold standard of digital subtraction angiography (DSA) findings,the dual energy cerebral arteries CTA imaging features of 30 cases confirmed by DSA for cerebral aneurysm were retrospectively analyzed.The diagnosis accuracy of cerebral aneurysm between dual energy cerebral arteries and DSA was compared.Results Dual energy cerebral arteries CTA could display the direct signs of cerebral aneurysms,it played better in the signs of aneurysm of the siphon segment of internal carotid artery than that by conventional cerebral arteries CTA.The measurement of the size and neck by dual energy cerebral arteries CTA had good agreement to DSA,there was no statistical difference (P ＞ 0.05).The radiation dose of dual energy cerebral arteries CTA was 19.1-25.4(21.7 ± 0.5)mSv.Conclusion The dual energy cerebral arteries CTA can show the size and neck of cerebral aneurysm clearly,has high value in clinical application of the diagnosis of cerebral aneurysm.
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Objective To compare the bone mineral density of the regions of femoral and tibial tunnels for anterior cruciate ligament(ACL)reconstruction in order to provide reference for the choice of optimal screw diameter for interference fixation.Methods Thirty healthy volunteers aged from 18 to 35 years were enrolled in our study,and the dual-energy X-ray absorptiometry(DEXA)was used to measure the bone mineral density of femoral and tibial tunnel regions of the right knee.All the right knees of the volunteers were also scanned by spiral CT and three-dimensional reconstruction technique was utilized to determine the circular sections that pass through the longitudinal axis of the femoral and tibial tunnels separately.The CT gray scale values of the Sections were measured.From August to October 2010,9 patients who had been diagnosed as ACL rupture underwent the operation of ACL reconstruction,and cylindrical cancellous bone peg was removed from the femoral and tibial tunnel respectively during the operation.Volumetric bone mineral density of the bone pegs were measured by using a standardized immersion technique according to Archimedes’ principle.Results Measured by DEXA,bone density of the femoral tunnel region arid tibial tunnel region were(1.162±0.034)g/cm2 and(0.814±0.038)g/cm2 respectively.The difference was significant between the femoral and tibial tunnel region(t=9.11,P=0.000).The CT gray scale value of the section for femoral tunnel region was(211.7±11.5)Hu,while that of the tibial tunnel region was(104.9±7.4)Hu.There was statistically significant difference between them(t=10.15,P=0.000).The volumetric bone mineral density of the bone peg from femoral tunnel and tibial tunnel were(2.80±0.88)g/cm3 and(1.88±0.59)g/cm3 respectively.The difference was statistically significant(t=4.32,P=0.002).Conclusion For ACL reconstruction,bone mineral density of femoral tunnel region is higher than that of the tibial tunnel.
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Objective To evaluate the clinical value of dual-energy CT in the detection of monosodium urate crystals in patients with gout.Methods One hundred and eight patients who experienced unilateral arthrocele and (or) joint pain in the past two weeks were enrolled into our study.DECT were performed for the upper or lower extremity.Ninety-five patients were enrolled into the gout study group based on the American rheumatism association (ACR) classification standard;The 0.3 linear blended images group were regarded as conventional CT group,DE (80 kV and 140 kV) datasets were reconstructed via gout-recognition software,the pseudo-color images group as the postprocessed group.Imagings were reviewed independently by two senior radiologists.Chi-square test were used for statistical analysis with the SPSS 13.0software.Results In the conventional CT group,DECT scans revealed a total of 298 areas of urate deposition in 51 patients;The sensitivity,specificity,and accuracy were 53.7％,84.6％,and 57.4％.In the postprocessed group,401 areas of green urate deposition were detected in 69 patients,the sensitivity,specificity,and accuracy were 72.6％,100.0％,75.9％ respectively,the differences had statistical significance (x2 =7.329 and 8.333,P ＜ 0.05).Conclusions DECT gout recognition technology can detect smaller amount of monosodium urate in the other parts of the body,with a great potential in early diagnosis and treatment monitoring of patients with gout.
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Objective Using the Chinese anthropomorphic chest phantom to measure the absorbed dose of various tissues and organs under different noise index, and to assess the radiation dose of MSCT chest scanning with the effective dose(ED). Methods The equivalence of the Chinese anthropomorphic chest phantom(CDP-1C) and the adult chest on CT sectional anatomy and X-ray attenuation was demonstrated. The absorbed doses of various tissues and organs under different noise index were measured by laying thermoluminescent dosimeters(TLD) inside the phantom, and the corresponding dose-length products(DLP) were recorded. Both of them were later converted into ED and comparison was conducted to analyze the dose levels of chest CT scanning with automatic tube current modulation (ATCM) under different noise index. Student t-test was applied using SPSS 12.0 statistical software. Results The Phantom was similar to the human body on CT sectional anatomy. The average CT value of phantom are -788.04 HU in lung,45.64 HU in heart,65.84 HU in liver,254.32 HU in spine and the deviations are 0.10%,3.04%, 4.49% and 4.36% respectively compared to humans. The difference of average CT value of liver was statistically significant(t=-8.705,P＜0.05),while the differences of average CT values of lung, heart and spine were not significant(t value were -0.752,-1.219,-1.138,respectively and P＞0.05).As the noise index increased from 8.5 to 22.5, the DLP decreased from 393.57 mGy·cm to 78.75 mGy·cm and the organs dose declined. For example, the average absorbed dose decreased from 22.38 mGy to 3.66 mGy in lung. Compared to ED calculating by absorbed dose, the ED calculating by DLP was lower. The ED values of the two methods were 6.69 mSv and 8.77 mSv when the noise index was set at 8.5. Conclusions Application of the Chinese anthropomorphic chest phantom to carry out CT dose assessment is more accurate. The noise index should be set more than 8.5 during the chest CT scanning based on ATCM technique.
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Objective: To determine the effectiveness and validity of morphometric analysis made from dental panoramic tomograms (DPTs) for predicting mandibular bone mineral density (BMD) while taking the result of dual energy X-ray absorptiometry (DXA) as gold standard. Methods: Twenty healthy subjects (8 male, 12 female) with intact dentition, aged from 11-26 years old, were included in the present study. The BMD of each patient was measured at the lumbar spine (L1 -L4,) by DXA; the results were obtained based on the density of surface (g/cm2). Dental panoramic radiography was carried out using dental panoramic tomography (RTG230/ ENR, made in Italy). Mandibular cortical thickness (MCT) and panoramic mandibular index (PMI) values were calculated and their relationship with DXA measurements were subjected to correlation analysis. The validity of MCT and PMI measurements were assessed by sensitivity and specificity. Results: We found mandibular BMD was positively correlated with MCT (r=0. 268, P<0. 05) and PMI (r=0. 251 3, P<0. 05). The sensitivity, specificity and Youden index of MCT were 50%, 93. 75%, and 0. 437 5, respectively; the numbers of PMI were 50%, 87. 50%, and 0.375, respectively. Conclusion: MCT and PMI might be potential indicators for mandibular BMD; they are simple and applicable in clinic.
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Objective To investigate the correlation between vertebral diffusion weigllted imaging (DWI)and dual X-ray absorptiometry(DXA),quantitative computed tomography(QCT)for the evaluation of bone mineral density(BMD).Methods A total of 152 female volunteers[aged from 30 to 80 years,mean age(58.2±14.2)years 1 were recruited in this study.All subjects underwent lateral thoracicolumbar radiographs,dual X-ray absorptiometry(DXA)and quantitative computed tomography(QCT),as well as DWI examination.Lateral spine radiographs(T4-L4)were evaluated with Genant's semiquantitative assessment.BMD was obtained by both DXA and QCT at lumbar spine(L2-L4).Axial vertebral(L2-4)DWI was performed with single shot spin-echo echo-planar imaging(SS-SE-EPI)sequenee (b value=500 s/mm2)after routine MRI examination(saginal T2 WI,T1 WI and axial T2 WI).Apparent diffusion coefficient(ADC)was measured with GE-Functool DWI software.Pearson correlation analysis was used for the statistics.Results There was a decreasing tendency in ADC value with age.A positive correlation was found between ADC(0.241×10-3 mm2/s)and BMD results measured by both DXA (1.038 S/cm3)and QCT(104.2 mg/cm3)examinations(r=0.461,0.731,respectively,P＜0.01).Conclusion DWI is an useful tool for noninvasive evaluation of the pathophysiologic changes of bone marrow in volunteers with difierent bone mineral density.
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Objective To observe the effect of ageand menstrual statuson body composition in healthy Beijing women.Methods We measured body composition with dual-energy X-ray(GE Lunar Prodigy)in 316 healthy Beijing females aged 20 to 74 years(5-7 cases per age).Parameters provided by the software were as following:total body bone mineral content,lean mass,fat mass and fat percentage(% fat).Local regions measured included arm,leg,trunk,android region and gynoid region.Body mass index (BMI),fat mass index(FMI),free fat mass index(FFMI)and A/G were calculated.Volunteers were assigned to 6 groups according age by every ten years a group.Results BMC peaked during the 4th decade,LM peaked during the 5th decade,with a decline of 18.1%and 5.2%respectively at age 74 years.Total body fat mass and % fat showed a general increase with aging throughout the studied age range.Total body fat mass increased from 16±5 kg at age 20-29 years to 24±6 kg at age 70-74 years,while % fat increased from 31.3%to 39.5%.All local region % fat increased with aging at different extents.Android region % fat showed the largest raise extent(32.2%).BMI increased gradually from 21.1 kg/m2 at age 20-29 years to 26.1 kg/m2 at age 70-74 years.FMI changed more obviously than FFMI.A/G increased from 0.85 at age 20-29years to 1.02 at age 70-74 years.Different menstrual status in women of 40-59 vears had obvious eflfect on A/G and BMC(P＜0.05),while it had no significant effect on BMI.body weight and waist circumference(P＞0.05). Conclusions Aging and menstrual status have evident effect on body composition distribution in healthy Beijing women.
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Objective: To investigate the characters of body composition of gastric cancer patients.Methods: Body composition was measured by dual-energy X-ray absorptiometry(DEXA)in 50 gastric cancer patients and 31 healthy subjects,and nutritional state was evaluated by mini nutritional assessment(MNA).Results: Compared with control group,male gastric cancer patients showed a reduction in lean body mass and fat mass(15 658?6 481)g vs(19 527?6 150)g,t=2.079,P
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0.05),that is to say, IRR couldn′t be improved just because the grade of the hospital was higher. (3)Comparing the photographic department with the non photographic one, we could see there was noticeable difference(? 2=4.081 3, P
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Objective To analyze sampling frequency and grid density frequency on the computed radiography(CR)system and to develop an effective method to suppress or eliminate grid artifacts.Methods To test grids with different grid-density in combination with IP boards of different specifications. Radiographic images with various qualities were obtained by simulating two kinds of signaling frequencies (namely two kind of grids with different grid densities),and utilizing three kinds of sampling frequencies (6,8,10 pixels/mm).A variety of different simulation images were obtained.Results By comparing simulation images with actual images,it was discovered that correct signaling frequency could be achieved if the sampling frequency were equal to twice the signaling frequency.The obtained image was clear and free of grid artifact.A grid density of
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Objective:To determine the effectiveness and validity of morphometric analysis made from dental panoramic tomograms(DPTs) for predicting mandibular bone mineral density(BMD) while taking the result of dual energy X-ray absorptiometry(DXA) as gold standard.Methods: Twenty healthy subjects(8 male,12 female) with intact dentition,aged from 1126 years old,were included in the present study.The BMD of each patient was measured at the lumbar spine(L1-L4) by DXA;the results were obtained based on the density of surface(g/cm2).Dental panoramic radiography was carried out using dental panoramic tomography(RTG230/ENR,made in Italy).Mandibular cortical thickness(MCT) and panoramic mandibular index(PMI) values were calculated and their relationship with DXA measurements were subjected to correlation analysis.The validity of MCT and PMI measurements were assessed by sensitivity and specificity.Results: We found mandibular BMD was positively correlated with MCT(r=0.268,P
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Objective To investigate the age related bone mineral density and the prevalence of osteoporosis at different skeletal sites in old women(age super-40 years) in Changsha countryside. Methods 627 healthy women from Changsha countryside (40 to 85 years)were involved. BMD measurements were taken at various sites,included anteroposterior and lateral lumbar spine, hip and forearm by Hologic QDR4500A dual energy X-ray absorptiometry (DEXA). Data were analyzed in-groups divided by an interval of every 5 years of age.Results ⑴Compared with 40 years～ old women, 75～85 years old women's total bone loss rates were highest at the word's triangle (56 62%) and lowest at the 1/3 site of the distal forearm (29 82～31 43%). ⑵The rank of osteoporosis detection rate from high to low after age 40 was lateral lumbar spine (38 72%), forearm, ward's triangle (27 52%) and anteroposterior lumbar spine ; femur neck and major trochanter (8 28% and 8 85%).⑶the prevalence of osteoporosis at least at one site of these women were(1 127?1 3)% in the age of 40～, (2 3?3 99)% in the age of 45～, (10 16?9 2)% in the age of 50～, (28 85?15 63)% in the age of 55～,(46 55?21 35)% in the age of 60～, (63 31?20 62)% in the age of 65～, (76 67?17 5)% in the age of 70～, (77 07?17 67)% in the age of 75～85. Before 60 years old the prevalence of osteoporosis stands out at lumbar spine (P
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Objective To compare dual-energy X-ray absorptiometry T-score concordance between hip and lumbar spine, and to estimate the value of T-score of the hip for diagnosing osteoporosis in the elderly. Methods From September 2000 to May 2002, 123 males aged 60-89 years (average 72.0?7.4) and 137 females aged 60-88 years (average 67.3?6.1) were selected in the study based on the exclusion of subjects with apparent abnormalities affecting bone mass or taking medications which might affect bone metabolism. Detailed questionnaire included lifestyle factors such as smoking, drinking, exercise and dietary habits, etc. Radiographs of the thoracic and lumbar spine were taken. Patients' BMD were measured by DEXA (DMS, Challenger) at lumbar spine (L 2-4) and left hip in posterior-anterior projection. The right hip was scanned if patients had a history of fractures or any bone disease in the left hip. All data were statistically analysed using SPSS 8.0 system. Results The average T-scores of bone mineral density of the lumbar spine were higher than that of the hip in all male patients and in 65-, 85- age groups of female patients(P
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In this paper,we analysed the plain film of spine and CT bone mineral density(BMD)of lumbar vertebral body in 63 Chinese osteoporotic women. There are 29 and 34 cases with and without fracture respectively in these patients. The average value of BMD in the fracture group was markedly lower than that of the non fracture group (P=0.0006).We suggested that 95mg/cm￣3 may be taken as an appropriate fracture threshold for Chinese elderly women, There were 18 and 45 cases with and without heterogenous calcification respectively in these patients.A significant difference of BMD was found between the two groups(P
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Objective To establish the reference databases for bone mineral density(BMD)in multiple skeletal regions,which would be useful for diagnosis of osteoporosis(OP)and prediction of fracture risk in adult women in Qingdao.Methods BMD was measured by dual-energy X-ray absorptiometry at skeletal regions of lumbar spine,left hip(femoral neck,Ward's triangle and greater trochanter)in 868 healthy adult women aged 25- 83 years and 191 women with fractures.BMD of skeletal regions with age-related change was found to fit in 8 kinds of regression models.Best model equations of fitting were found and the reference database was established.BMD of women with fractures was compared with the reference databases to predict the risk of fracture.Results BMD in 6 skeletal regions changed with aging and a cubic regression model was better fitted with aged-related change as compared with other regression models.The coefficients of determination(R~2)of fitting curve were 0.21?0.09 (P＜0.01).The BMD reference databases of women in Qingdao were established by cubic regression equation, the peak BMD of lumbar spine and hip appeared at 25-29,and 40-44 years old groups respectively.Finally,the BMD in fracture group was significantly decreased by 1.6-2.5 s as compared with the peak BMD of health women. Conclusion The bone quantity is lost rapidly after 45 years old in women.If the BMD in women after 50 years old is decreased by 1.6-2.5 s compared with the peak BMD in the same area,the risk of fracture is increased.