RESUMEN
Objective To evaluate the radiation dose and image quality of MinDose techniques in dual-source CT coronary artery angiography.Methods 120 consecutive patients undergoing cardiac CT scans were randomly assigned into 2 groups: Group A1 with the tube current reduced to 20% of the normal tube current outside the pulsing window,and Group A2 with the tube current reduced to 4% of the normal tube current outside the pulsing window (MinDose).The image quality,noise,volume CT dose index (CTDIvol),and effective dose (E) of these two groups were evaluated.Results The mean score of imaging quality of Group A1 was (4.3 ± 0.3 ),not significantly different from that of Group A2 [(4.5 ±0.4),t=0.16,P＞0.05].The value of CTDIvol of Group A1 was (40.2 ±9.6) mGy,significantly higher than that of Group A2 [( 36.4 ± 9.1 ) mGy,t = 3.2,P ＜ 0.05].The E value of Group A1 was (9.1± 2.2) mSv ,significantly higher than that of A2 [( 8.1 ± 1.9) mSv,t = 2.7,P ＜ 0.05].Conclusion Application of the MinDose technique not only reduces the radiation dose to the patient,but also meets the requirement of diagnosis.
RESUMEN
Objective To investigate the effects of hyperbaric oxygenation(HBO)therapy on serum cytokines and depression in post-stroke depression(PSD)and to study it's clinical implications.Methods Sixty patients with PSD were divided into two groups.Patients in routine treatment group(RT group)were treated with routine clinical treatment,whereas those in HBO group were treated with HBO therapy in addition to routine clinical treatment.The serum cytokines of tumor necrosis factor-α(TNF-α)and interleukin-1β(IL-1β)were measured by enzyme-linked immunosorbent assay(ELISA)before and after 30 days of treatment.All the patients were evaluated with Hamilton depression scale(HAMD),Chinese stroke scale(CSS)and Barthel index(BI).The evaluations were carried out at the 0 and 30 d.Results Before treatment,the concentrations of TNF-α and IL-1β in patients with PSD were significantly higher than those in patients with cerebral infarction without depression(P＜0.01),and the serum levels of TNF-α and IL-1β in those with serious depression were higher than those with moderate and mild depression(P＜0.01),and that in moderate depression patients were higher than that in mild depression patients{P＜0.01).At the 30th d post-treatment,those parameters all decreased significantly in RT group and HBO group(P＜0.01,P＜0.05).Moreover,those parameters were lower in HBO group than those in RT group(P＜0.01),and HAMD,CSS and BI scores in HBO group were significantly better than that in RT group(P＜0.05,P＜0.01).Conclusions Serum cytokines levels increased significantly in patients with PSD and were associated with the severity of depression.Serum cytokines might played an important role in pathogenesis of PSD.HBO therapy could help decrease the levels of TNF-α and IL-1β.HBO might exert therapeutic effect by reducing secondary the inflammatory injury in acute cerebral infarction.
RESUMEN
Objective To analyze the correlation factors affecting DSA picture quality and to investigate the DSA value and effectiveness in hepatic arteriography. Methods 36 cases with liver tumor were analyzed through femoral artery intubatton with Seldinger and had hepatic arteriography with RH catheter. Results In the 192 images of 36 cases,the percentage of first-rate image was 92.7%,the second-rate image (9/192) was 5.3%,the third-rate image (5/192) was 2%. Conclusion All of the second-rate images and the third-rate images which were handled with selective image postprocessing can improve picture quality and can reach diagnosis request.
RESUMEN
Objective To evaluate the clinical application of the auto trigger technique with dual-source CT in cerebral and cervical vessel. Methods 35 patients were randomly divided into three groups, taking triggered threshold as 20HU,50HU and 70HU respectively, CT-values in segments of left middle cerebral artery, superior sagittal sinus, left common carotid artery adjacent to the fourth cervical vertebrate and internal jugular vein by injection at antecubital vein were all measured. Results The discrepancy of peak in artery among groups was not statistically different. It was statistically different in the same segments of vein. Conclusion CTA of cerebral and carotid arteries with the dual-source CT triggered technique can be clearly showed with 20HU as triggered threshold.
RESUMEN
Objective To introduce the techniques and clinical application of coronary arterial calcification measurements by using the multi-slice CT (MSCT). Methods The recent literature on the coronary artery calcium scoring with MSCT were reviewed. The data acquisition, image reconstruction, quantification methods in assessment of calcium and usefulness of calcium scoring in coronary artery disease were investigated. Results MSCT with nearly isotropic volumetric imaging data, subsecond rotation and retrospective electrocardiographic gating could provide better input data for quantification of coronary arterial calcium volume. Conclusion MSCT allows more precise and repeated measurement of coronary arterial calcification with low interexamination variability.
RESUMEN
Objective With the increasing of the CT examination, the dose of x-ray has been brought to public attention. For the sake of making the MDCT technology better applied, available optimal technology has to be used to reduce the x-ray dose to the patients. Methods Many optimal technologies were involved in, such as ECG modulation, cardiac bowtie, 3D dose modulation, compact geometry design, electron collector and speed 4D CARE dose. Results The result of the research showed that the dose of scanning x-ray of CT could be decreased sharply by using optimal technologies. The Q2 values was the standard which could well evaluate the quality of the CT′s images and the dose of x-ray. Conclusion The quality of images and the dose of x-ray can′t be separated, which must be quoted together.
RESUMEN
Digital X-ray imaging technique has been developing rapidly in recent years, and makes it possible for people to be radiated by lower X-ray dose than before to get the images for diagnosis. Current development in 7 aspects about digital roentgenography is introduced in this article.
RESUMEN
Objective To study the scan parameter of spiral CT angiography in aortic dissection.Methods 34 cases with aortic dissection successively underwent SCTA were studied retrospectively.The CT scan parameters,methods of posteriorimage treating were reviewed and analysed one by one.Results In 34 cases,32 cases were diagnosed as aortic dissection and classified correctly,in accordance with the result of operation and DSA,the quality of image was satisfied and the rate of success at least above 88.9%.The use of main scan parameters:(1)the ascend aortic dissection:slice thickness 4 mm,reconstruction interval 2 mm,pitch 1.25;tube current 175 mA;(2)involed in ascend,arch,descend and throacic aorta dissection:slice thickness 5 mm,reconstruction interval 2～3 mm,pitch 1.5;tube current 150 mA;(3)involved in abdominal aortic dissection:slice thickness 6～8 mm,reconstruction interval 2～3 mm,pitch 1.5 or 1.75;tube current 125 mA.The tube voltage all were 120 kV,the dosage of contrast media was 90～100 ml;the delayed scan time was choiced 20 second in throacic aortic and 25 second in abdominal aortic.The posterior image methods main used MPR,SSD,MIP and VR. Conclusion To set a sensible scaning plan,choose and match scan parameters properly according to the scaning length,can avoid the shortage of restrain SCTA scaning length and get satisfied image.
RESUMEN
The construction of 64-slice-dual-source computed tomography(DSCT) is introduced.Its imaging principle and clinical application are put forward.DSCT has special advantages in diagnosing coronary stricture.The principles of DSCT and energy subtraction imaging are expatiated in detail.DSCT has great value in clinical research and application.
RESUMEN
Objective To study the effect of image quality and radiation dose by using Z -axis automatic tube current modulation(ATCM),as well as the application of automatic tube current modulation technology.Methods A control group consisting of 25 patients underwent cervical MDCT with fixed-current technique(100-220mA).Of two study groups of 25 patients,one underwent cervical MDCT using z-axis ATCM with the noise index of NI10 and tube current intensity of 80-480 mA,and the other with the noise index of NI12.5 and tube current intensity of 80-369 mA.The noise and mean tube current-time products(mAs) were recorded.Two radiologists evaluated images for diagnostic acceptability.Results All CT examinations of study and control groups were diagnostically acceptable,though objective noise was different with z-axis ATCM than with fixed current.ATCM resulted in significant radiation dose reduction(NI10,94.8?17.9 mAs;NI12.5,74.8? 18.3 mAs),when compared with the fixed current(130.4?43.1 mAs).Conclusion Z-axis Automatic mA technique has no significant change in image quality when compared with the fixed mA technique,but the radiation dose is decreased by 27%(NI10) and 43%(NI12.5),for MDCT evaluation of neck.NI has to be selected on the basis of the tissue,lesion size and nature.
RESUMEN
In multilayer spiral CT heart and coronary artery imaging, image data are acquired by ECG gating technology when heart beats slowest so as to restrain pulsation pseudo-image. ECG gating technology includes foresight ECG gating and retrospective ECG gating. The principle, methods and mutual image reconstruction are introduced in this paper.