RESUMEN
Objective:To explore the clinical application value of pre-breathing mode in double-low imaging of 320-slices computed tomography(CT)for pulmonary artery.Methods:A total of 100 patients who underwent CT pulmonary angiography(CTPA)for suspected pulmonary embolism(PE)in Liuzhou People's Hospital from July 2021 to September 2022 were prospectively selected as the research subjects and they were randomly divided into observation group and control group,with 50 cases in each group.The patients of the control group adopted conventional breathing mode(the breathing password was activated after reaching the threshold,and the scan was triggered after 6 s),while the patients of the observation group adopted the pre-breathing mode(the breathing password was activated after 1 or 2 seconds,and the scan was triggered after reaching the threshold).Both two groups adopted double low-technique scan of 320 slices CT.The differences in delay time,radiation dose,the points of subjective and objective image quality,and other indicators were compared between the two groups.Results:The volume CT dose index(CTDIvol),dose length product(DLP),effective dose(ED)and delay time of the observation group were significantly lower than those of the control group(t=76.230,30.225,12.282,7.088,P<0.05),respectively.The comparison of the subjective points of image qualities between the two groups indicated that there were 25 cases with 5 points,23 cases with 4 points and 2 cases with 3 points in the observation group,and there were 21 cases with 5 points,26 cases with 4 points and 3 cases with 3 points in the control group.There was no significant difference in the averagely subjective points of image qualities between two groups(P>0.05).The signal-to-noise ratio(SNR)and signal to noise ratio(CNR)of the observation group were significantly lower than those of the control group,and the noise level(SD)of the observation group was significantly higher than that of the control group(t=25.441,23.886、11.426,P<0.05),respectively.The CT values of the artery trunk of right pulmonary,artery branch of right pulmonary,artery trunk of left pulmonary and artery branch of left pulmonary in the observation group were significantly higher than those in the control group(t=2.256,2.225,2.042,2.277,P<0.05),respectively.Conclusion:The pre-breathing mode can effectively improve CTPA image quality,and reduce radiation dose and the dosage of contrast agent,which clinical application effect is significant.It is worth learning.
RESUMEN
Objective To explore the efficacy of double low-profile visualized intraluminal support (LVIS) stent assisted embolization in the treatment of acute intracranial wide-neck aneurysms and its relation with levels of soluble intercellular adhesion molecule-1 (SICAM-1) and S100B. Methods A total of 114 patients with acute intracranial wide-neck aneurysms admitted to our hospital from June 2014 to December 2018 were collected. According to different treatment options, the patients in the study group (n=58) were treated with double LVIS stent-assisted embolization, while those in the control group (n=56) were treated with LVIS stent-assisted embolization. The embolization degrees of intracranial wide-necked aneurysms were evaluated by Raymond grading immediately after surgery, the efficacy of the patients was evaluated by modified Rankin scale (mRS) at discharge, and the serum SICAM-1 and S100B protein levels of the patients with different treatment methods and different curative effects before and after surgery were compared. Results As compared with those in the control group, the degrees of arterial embolization immediately after surgery and good therapeutic effect rate at discharge were significantly higher in the study group (P<0.05). After treatment, the serum levels of SICAM-1 and S100B were significantly lower in the study group than those in the control group (P<0.05). The levels of SICAM-1 and S100B in patients with good therapeutic effect ([147.5±9.8] mg/mL and [0.106±0.027] mg/mL) were significantly lower than those in the patients with poor therapeutic effect ([172.8 ±4.0] mg/mL and [0.158±0.002] mg/mL, P<0.05). Conclusions The embolization rate and therapeutic effect can be significantly improved in patients with acute intracranial wide-neck aneurysms after double-LVIS stent-assisted embolization. The serum levels of SICAM-1 and S100B are significantly increased in patients with poor therapeutic effect.
RESUMEN
Objective To investigate the clinical feasibility of spectral monochromatic imaging combined with adaptive statistical iterative reconstruction-V (ASIR-V) in upper abdominal enhanced scanning with double-low technique for severe liver cirrhosis.Methods Totally 126 cases performed abdominal contrast-enhanced CT scanning were collected prospectively and assigned to 3 groups with 42 cases in each group with random number table method.The filtered back projection algarithm,120 kV and contrast agent dose of 420 mgI/kg were used for the cases of control group.The cases for spectral group and combined group were scanned with spectral imaging mode and contrast agent dose of 300 mgI/kg.The 60 keV monochromatic images combined with pre-0％ and post-40％ ASIR-V were selected and analyzed for spectral group.Combined group with pre-40％ ASIR-V was divided into 2 subgroups with 50 keV,post -50％ ASIR-V and 60 keV,post-40％ ASIR-V separately.One-way ANOVA test was used for analysis of radiation dose and quantitative parameters,and Rank sum test was used for image subject evaluation.Results The CT numbers and CNR had significant differences among spectral group,combined group and control group(F=4.293-13.134,P＜0.05) except for the images of liver parenchyma in PVP and that of 50 keV combined 50％ASIR-V group were higher than that of control group (q=1.825-3.736,P＜0.05).No significant differences existed for image noise and overall image quality scores of organs in four groups.The visualization of hepatic vascular branches in 50 keV combined 50％ASIR-V group was higher than that of other three groups(Z=2.793-6.328,P＜0.05).The radiation dose of combined group was lower than that of spectral and control group (q =-4.879--2.531,P ＜ 0.001).Conclusions Spectral monochromatic imaging combined with pre-and post-ASIR-V can reduce contrast agent dose and radiation dose without degrading image quality for the severe liver cirrhosis in upper abdominal enhanced scanning.
RESUMEN
The development of CT and the clinical application of CT pulmonary angiography (CTPA) in diagnosing pulmonary embolism were introduced,and the methods for decreasing CTPA radiation dose and the importance of iterative reconstruction for low-dose scanning were analyzed.The development and application of contrast agent were described,and the ways to reduce contrast agent dose was expounded.Double-low CTPA combined with iterative reconstruction was pointed out to decrease greatly the radiation dose and contrast agent iodine dose while ensured image quality,and thus the damages to the patient by radiation and contrast agent could be lowered at the most.
RESUMEN
Objective To probe the application value of “double low”CTU method in diagnosis of urinary system malformation in children.Methods Patients with urinary system malformation were screened by ultrasound,and renal calculi,tumor and tumor-like lesions were excluded.Double phase contrast media injection (iodixanol contrast media 270 mg I/mL)was used in one phase scan-ning,and the cortex-secretory phase images were obtained.The images were reviewed and evaluated independently by two readers. Results The coincidence rate of diagnosis was 100% with well images quality.Conclusion CTU is an important tool for the diagno-sis of urinary tract malformations in children.The “double low”method with lower radiation dose and contrast media quantity may ensure the quality of diagnosis.
RESUMEN
Objective To investigate the feasibility of double low scanning technique using the gem spectrum CT coronary artery angiography among the patients at low heart rate≤ 65 beats per minute.Methods This prospective study was approved by the institutional re-view board with patient informed consent.Ninty patients (heart rate≤65 beats per minute)were randomly devided into 3 groups.Group A un-derwent spectral CCTA with iodixanol (Visipaque,270mg/mL)and low scanning technique,Group B conventional CCTA with iohexol (Omnipaque,370 mg/mL)and Group C conventional CCTA with iodixanol (Visipaque,270 mg/mL),Routine scan mode was used in Group B and Group C.Prospective ECG gating mode was used in all groups.120kVp polychromatic images with FBP algorithm (Group B and Group C)were reconstructed for conventional CCTA,60 keV monochromatic images with FBP algorithm (Group A) or with a fixed blending level (40%)of ASiR (Group A1 )were reconstructed for spectral CCTA.Compared the image quality of four groups and ED in three groups.Results The difference was ststistically significant between four groups with the CT value,im-age noise,SNR and CNR of coronary (each P<0.001.Group A1 has the highest SNR and CNR.Group C has the lowest image noise.There were no significant difference of coronary score between group A1 and group B(χ2=0.01,P=1.000)).There was significant difference of coronary score between group A and group B (χ2=22.428,P<0.001),group B and group C (χ2=39.005,P<0.001), group A1 and group A (χ2=21.854,P<0.001).Effective radiation dose in the group A(ED2.60±0.26 mSv)was lower than that of group B (ED3.02±0.36 mSv)(t=3.738,P=0.001)and group C (ED3.11±0.23)(t=3.725,P=0.001).Conclusion Double low scan-ning technique using the gem spectrum CT coronary artery angiography with 40% blending level of ASiR is able to provide better im-age quality than using conventional CCTA and to reduce the effective radiation dose and contrast dose.