Objective To analyze the clinical application of monoenergetic technique of dual-energy CT in removing metal artifacts for patients with fractures fixed with metal fixer.Methods Fofly-five patients with fractures fixed with metal fixer underwent dual-energy CT scanning for the fractures.Two different data were collected in one-time scanning using dual-energy scanning sequence.With monoenergetic technique,two different data at 100 and 140 kilovolts were used for subtraction to removing metal artifacts based on different densities.Raw data were reconstructed with monoenergetic technique(group A)and conventional simulation method(group B),respectively.And,all data were reconstructed with multiplanar reconstruction (MPR),volume rendering(VR)and maximum intensity projection(MIP),respectively.Wilcoxon signed rank test was applied for the comparison of imaging quality and artifacts between the two groups.Results There were fewer artifacts on the images due to the application of monoenergetic technique in dual-energy CT scanning.In group A,the rate of high-quality images reached to 91.9%(124/135);and,in group B,it was 59.3%(80/135).There were statistical diference between the two groups(Z=-12.541.P<0.01).The images without artifact reached to 89.6%(121/135)in group A;whereas,it was 45.2%(61/135)in group B.There was statistical difference between the two groups(Z=-11.910,P<0.01).Conclusion Using monoenergetic technique,metal artifacts were removed effectively and the fine structure of fracture was clearly displayed.

The pharmacokinetics and content of 3H11-8H-HPD in tumor, liver, skin and muscular of tumor-bearing nude mice were reported and compared with free 3H-H'PD. The conjugated molar ratio of 3Hll-3H-HPD was 1 : 27. The 97% antibody activity of conjugate was retained. After 3Hll-3H-HPD or 3H-HPD iv into tumor-bearing nude mice, the pharmacokinetics parameter of blood-drug concentration indicated that the T1/2 of conjugate group was longer than that of 3H-HPD, the elimination rate constant ( Kel ) of conjugat group was larger than that of 3H-HPD group, but the aparent volume of distribution ( Vd ) of the former was less than that of the latter. Tissue distribution study reveald that the radioactivity in tumor tissue of conjugate was increased average 0.9 fold than that of 3H-HPD group. Tumor/liver ratio in both 3Hll-3H-HPD group and 3H-HPD group were 0.66 ? 0.24 and 0.42?0.20, respectively. Contents of 3Hll-3H-HPD in skin or muscular were decreased average 1 fold than that of free 3H-HPD, respectively. The study result was shown the pharmacokinetics characteristic of large molecule conjugate and the targeting action of monoclonal antibody.

Objective To compare the quality and radiation doses of coronary artery angiography under the natural heart rate condition between Flash spiral heart mode and prospective electrocardiogramtriggering sequence mode using dual-source,in order to choose personalized low doses of coronary artery scanning mode.Methods Sixty patients who underwent coronary angiography(CTA)on a 128-slice,dualsource CT scanner were divided into 2 group i.e,group A(27cases)and group B(33 cases).Flash spiral heart scan mode was employed for group A.Inclusion criteria included:heart rate<65 bpm.regular sinus rhythm,heart rate fluctuation less than ±5 bpm.Date acquisition was set at 60% of the R-R interval.Prospective electrocardiogram-triggering sequence scan mode(SAS)was performod for group B.Inclusion criteria included:(1)heart rate≥65 bpm,(2)arrhythmias,premature beat,fibrillation atrial.Exclusion criteria included:bad holding breath.Date acquisition(1)At low heart rate(≤75 bpm),date acquisition was set at 60%-80%of the R-R interval.(2)At high heart rate(>75 bpm),date acquisition was set at 30%-50%of the R-R interval. (3)At the arrhythmias,premature beat,fibrillation atrial,date acquisition was set at 20%-90%of the R-R interval.In both gronps,patients with a BMI≥25.0kg/m2 were examined with a tube voltage of 120 kV.while the other patients with a BMI<25.0 kg/m2 were examined with a tube voltage of 100 kV.The BMl was(24.6±1.0)kg/m2 in group A,while that was (24.6±0.9)kg/m2 in group B.In both groups,all images were transferred to the workstation for further processing and analysis.The imaging quality of coronary artery segments and the radiation dose were compared with t test.Results A total of 336 coronary artery segments were evaluated in group A and 412 segments were evaluated in group B.The imaging quality of coronary artery segments were scored.Excellent or good was achieved in 98.2%(330 of 336)artery segments in group A,and that was 98.1%(404 of 412)in group B.There was no statistical difference in imaging quality between the two groups(t=0.513,P=0.608).The average effective dose was(0.74±0.29)mSv in group A,whereas that was(3.67±1.37)mSv in group B.There was a significant difference between the two groups(t=-10.858,P=0.000).Conclusions The personalized low doses coronary artery scanning mode can substantially reduce radiation damage while preserving good imaging quality.

Objective To evaluate the application value of superb micro-vascular imaging (SMI) technology in gastric cancer.Methods Data of color Doppler flow imaging (CDFI) and SMI of 69 patients with gastric cancer confirmed by pathology were analyzed retrospectively.The positive rate in displaying the blood flow,the thickness of gastric carcer lesion with blood flow signal and the grade of blood flow obtained with CDFI and SMI were compared.Results The positive rate of blood flow was 75.36％ (52/69) of CDFI and 95.65％ (66/69) of SMI,respectively.The difference of positive rate between the two methods was statistically significant (x2 =11.461,P=0.001).The thickness of gastric cancer lesion with blood flow signal measured with CDFI was (19.92±4.54)mm,and that measured with SMI was (16.92±5.77)mm (t=2.048,P=0.043).There was statistical difference of the grades of blood flow between SMI and CDFI (Z=5.354,P＜ 0.001).Conclusion SMI technology is more sensitive for the low flow velocity of micro vessels signal in gastric carcinomas compared with CDFI,which can provide valuable reference for clinic.

OBJECTIVESSonotubometry is wildly used in developed countries, offers a easy, versatile and objective way to assess the function of Eustachian tube. The objectives of this study are to develop a low-cost digitalized device.

METHODSThe digitalized sonotubometry device was made of a personal computer with sound input and output accessories. The PC sound card, connected to a signal amplifier, exported probe band noise, while feedback sound was collected by a microphone. All 36 volunteers (72 ears) were involved in the sonotubometry test with JK-04A and CHN-08, in the conditions of dry-swallowing and wet-swallowing. The data were statistically analyzed using SPSS 13.0.

RESULTSThe basic electroacoustic performance of the CHN-08 was acceptable. CHN-08 (7 kHz) detection and JK-04A consistency of kappa index was 0.472; CHN-08 (8 kHz) and JK-04A consistency of kappa index was 0.487; CHN-08 (7 kHz) and CHN-08 (8 kHz) consistency of kappa index was 0.688.Under the JK-04A, CHN-08 (7 kHz) and CHN-08 (8 kHz) three setups, Eustachian tube opening frequency was significantly lower for wet-swallowing than dry-swallowing, P < 0.05.

CONCLUSIONSA low-cost digitalized sonotubometry is successfully developed. Its electroacoustic performance proved acceptable by authority assessments. The detection rate of CHN-08 is in accordance with that of JK-04A moderately. The study revealed that Eustachian tube is opened more easily by dry-swallowing than by wet-swallowing.

Acoustic Impedance Tests ; Audiometry ; instrumentation ; Equipment Design ; Eustachian Tube ; physiology ; physiopathology ; Humans ; Man-Machine Systems