Objective To explore the application of CARE kV technique in the adult chest CT and the value of reducing radiation dose.Methods Sixty-nine patients were divided into two groups by random number generators:group A(39 cases) and group B(30 cases).Group A was examined by using CARE kV technique and group B was examined at routine 120 kV.CT dose index(CTDIvol),dose length product (DLP) and effective dose (E) were compared between the two groups,and analyzed the correlation between tube voltage selection and patient body mass index (BMI) of group A was analyzed.Results The average CTDIvol [(11.00 ± 3.89) mGy],DLP[(294.05 ± 91.17) mGy·cm] and E[(4.12 ± 1.28) mSv] of group A were lower than those of group B (16.64 ± 1.20) mGy,[(475.99 ± 41.16) mGy · cm],[(6.66 ±0.58) mSv].With statistically significant difference (t =-7.653,-10.151,-10.150,P ＜ 0.05).Compared with routine 120 kV technique (group B),the CARE kV technique (group A) could reduce the total radiation dose about 38.14％.Compared obese patients(BMI≥28 kg/m2) with non-obese patients in group A and B,the mean E of non-obese patients was lower than that of obese patients in group A,which reduced the total E about 31.74％ (t =4.322,P ＜0.05),while E in group B was no significant different between non-obese patients and obese patients.Conclusions In adult chest CT,CARE kV technique can select optimum scanning voltage automatically according to the patients with different BMI and anatomical regions,which can reduce the overall radiation dose while maintaining image quality.

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.

Objective To evaluate the diagnostic value of multi-slice spiral CT(MSCT)perfusion imaging in chronic obstructive pulmonary disease(COPD).Methods Twenty COPD patients and20 volunteers underwent 8-row detector spiral CT(MSCT)perfusion imaging using cine scan mode with5 mm slice thickness.0.5 s rotation time and a total scan time of 45 s with 5 s intervals.60 ml contrast agent(300 mg I/ml)were administered at a rate of 4 ml/s from the forearm superficial vein.The imaging data were transferred to a workstation.A time-density curve and pseudo-color map were generated automatically with GE CT perfusion 3 software,the blood flow(BF),blood volume(BV),mean transit time(MTr)and permeability surface(PS)were measured.Results Time-density curve was flatter and the peak of the curve was obviously lower in COPD patients than the volunteers.The BF.BV.PS in COPD volunteers was(10.58 ±4.85)s and(4.50 ±1.71)s respectively.The BF,BV and PS in COPD patients Was lower than the volunteers,the MTY was higher(P＜0.01).Conclusion MSCT perfusion imaging is helpful for the diagnosis of COPD.

Objective To observe the CT features of ovary Brenner tumor. Methods CT manifestations of 5 patients with ovary Brenner tumor confirmed with pathology and clinical follow-up were retrospectively analyzed, and the masses were described for location, size, configuration, enhancement pattern, presence of calcification and metastatic spread. Results There were 7 tumors in 5 patients, 3 patients had unilateral tumors and 2 had bilateral Brenner tumors (left side 3 and right side 4), with tumor size ranging from 1.52 to 16.25 cm (mean 7.36 cm). Five masses in 4 patients were benign, 2 (bilateral tumors in 1 patient) were malignant. All tumors had well-defined margin. One patient with bilateral benign tumors had large pleural effusion and seroperitoneum. Five tumors in 4 patients (5/7, 71.43%) were solid and had calcification, 2 tumors in 1 patients (2/7, 28.57%) were mainly cystic, with septa in the tumors. The solid part of all tumors were inhomogeneous and had mild enhancement. Conclusion CT findings of ovary Brenner tumor have some characteristics. Combining with clinical manifestations, CT is helpful for the diagnosis of ovary Brenner tumor.

Objective To study the image quality and radiation dose in dual-source CT cerebral angiography with prospective ECG-triggered sequence mode (step-and-shoot,SAS).Methods A total of forty-three patients with clinically suspected cerebral vascular disease underwent cerebral CT angiography with prospective ECG-triggering (step-and-shoot,SAS).Data acquisition was at 60％ R-R interval of the ECG presentation mode.The post-processing included maximum intensity projection (MIP),multiplanar reformation (MPR) and volume rendering (VR).The CTA image quality,radiation dose and rates of excellent images were evaluated.Results The CTA image quality score was 4.72 ± 0.50 and 97.7％ (42/43) patients had excellent CTA images.The average effective dose of SAS-CTA was (0.22 ± 0.01 )mSv,which was lower by 76.31％ than that of DE-CTA.Conclusions Prospective ECG-triggering sequence could be used in cerebral angiography with a significant reduction in radiation dose and diagnostic image quality.

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 investigate the expression of CD133 and CD44 proteins in gastric stromal tumors (GST) and their clinical significances. Methods The expression of CD44 and CD133 proteins in the GST tissues of 112 patients was detected by immunohistochemical staining. The relation between the expression of CD44 and CD133 proteins and the clinicopathological characters was analyzed. The survival and prognosis of GST were also analyzed. Results Both CD44 and CD133 were expressed on the cell membranes. The expression rates of CD44 and CD133 were 58.04 % (65/112) and 42.86 % (48/112) separately; the co-expression rate of CD44 and CD133 was 27.68 % (31/112). CD44 and CD133 were negative in normal peritumoral tissues. No correlation was found between CD44 and CD133 and the clinicopathological parameters including gender, age and lymphatic vessel invasion (all P>0.05), but the expression levels of CD44 and CD133 in patients with the mitotic count ≥ 5/50 high-power field, large diameter and vascular invasion were significantly higher (all P<0.05). No correlation was found between co-expression of CD44 and CD133 and the clinical clinicopathological parameters including gender, age, the mitotic count ≥ 5/50 high-power field and vascular invasion (all P>0.05), but the co-expression level of CD44 and CD133 in patients with tumor diameter ≥5 cm was significantly higher than that in patients with tumor diameter < 5 cm (χ2=5.040, P=0.025). The overall survival rate of the patients with co-expression of CD44 and CD133 was shorter than that in other groups (χ2 = 8.758, P= 0.001). No correlation was found between CD44 and CD133 expression (r=0.126, P=0.210). Multivariate analysis with the Cox regression models showed that the tumor diameter ≥5 cm (P=0.042) and co-expression of CD44 and CD133 (P=0.003) were significantly associated with poor prognosis. Conclusion CD44 and CD133 as robust cancer stem cell markers in GST might be the prognostic factors.

Objective To compare the effect between Mammotome minimally invasive surgery and traditional surgery in resection of youth giant breast fibroadenoma (YGBF).Methods We randomly selected 73 patients who had YGBF and already accepted surgical treatment in our hospital from Jul.2009 to Jan.2016.The 75 patients recruited from screening programmes were alloted to either treatment according to their choice (37 cases in MS and 38 cases in traditional surgery).The median follow-up was 18 months (from 6 to 36 months).Comparative analysis was done between the two groups in operation time,incision healing time,incision length,intraoperative bleeding,wound infection,subcutaneous hematoma,residual tumor,breast deformation,scar size,and patient satisfaction degree.Results There was no statisticaly significant difference betwen these two groups in operation time,intraoperative blood loss,incision infection,subcutaneous hematoma,or residual tumor (P＞0.05),however,MS group was superior to traditional surgery group in the incision healing time,incision length,breast deformation,scar size and postoperative satisfaction degree,and the difference was statistically significant(P＜ 0.05).Conclusion The advantage of Mammotome minimally invasive operation auxiliary for YGBF is obvious,such as fast wound healing,small incision,infection rate,small breast without deformation and scar etc.,also higher satisfaction degree to the treatment,which is regarded as the preferred surgical treatment for YGBF patients.