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Objective:To investigate the feasibility of tube potential of 80 kV combined with personalized contrast agent protocol in carotid artery CT angiography (CTA).Methods:A total of 136 consecutive patients undergoing neck CTA were prospectively enrolled in this study. The patients were randomly divided into Groups A, B, C and D. Tube potential of 100 kV and 15 s contrast agent injection protocol was used for Group A (53 cases) as conventional group, while tube voltage of 80 kV and 10 s contrast agent injection protocol was used for Groups B, C and D as experimental groups, with the contrast agent dosages of 20, 25 and 30 ml used according to the body weights of ≤50 kg(Group B, 20 cases), 50-70 kg (Group C, 38 cases), and 70-90 kg (Group D, 25 cases), respectively. The subjective and objective evaluation results of image quality and the effective doses were compared among the four groups.Results:The effective doses in Groups B, C and D were 1.54±0.91, 1.89±1.08 and 2.14±1.27 mSv, respectively, significantly lower than that in Group A [(5.66±0.56) mSv] ( F=169.34, P<0.05). The image quality of four groups met the requirements of clinical diagnosis. No significant differences were found in subjective evaluation and diagnostic efficacy of the four groups ( P>0.05). The CT number of carotid artery, signal-to-noise ratio and contrast-to-noise ratio of the neck region were significantly lower in Groups B, C and D compared with Group A ( F=14.9, 12.94, 14.43, P<0.05). The CT numbers of target carotid vessel were all higher than 250 HU. Conclusions:The scanning protocol of low tube potential (80 kV) combined with 10 s contrast agent injection protocol could not only reduce the doses of radiation and contrast agent, but also preserve the diagnosis effect. Thus, this scanning protocol was feasible and valuable in clinical application.
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Objective To assess the influence on radiation dose and image quality of bronchial artery CT angiography for hemoptysis patients with high heart rate and free respiratory with single-cardiac dynamic volumetric scanning using 320-row CT.Methods During October 2016 and May 2017,totally 151 hemoptysis patients with heart rate ≥ 65 bmp and free-breathing were scanned for bronchial artery imaging with prospective ECG-gating 320-detector row dynamic volume CT.The patients were randomly divided into two groups,group A(81 cases) and group B(70 cases).Default multi-cardiac cycle scanning style was used for group A to generate multi-sector images A 1 which were reconstructed corresponding single-sector images A2.Single-cardiac periodic scanning was used to get single-sector images for group B.The effective doses (E) of two scanning types,the quantitative parameters of image quality [vascular CT value,image noise (SD),signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR)] and subjective scoring of group B and A1,A2 were compared.The detection accuracy of the systemic artery-pulmonary circulation shunts was evaluated by ROC curve against digital subtraction angiography (DSA).The measurement data was analyzed by independent sample t test while the grade data was tested by independent sample nonparametric test.Results The median value of radiation dose in group B was significantly lower than that of group A (1.42 mSv vs.3.06 mSv,Z=-8.724,P＜0.05).There were no statistically significant differences in quantitative parameters and subjective scoring points of image quality between group B and group A2 (P＞ 0.05).The median subjective scoring points of group B was 4,which was better than that of group A1 (Z =-10.584,P＜ 0.05).The differences of SD,SNR,CNR betweengroup B and group A1 were statistically significant(t =-0.983,7.898,7.695,P＜0.05),and group B had higher SD,SNR and CNR.There was no significant difference in the mean CT values of the aorta and pulmonary artery between the two groups (P ＞ 0.05).The detection accuracy of the systemic arterypulmonary circulation shunts was moderately high in group B and group A2.The area under the ROC curve (AUC) was 0.891 and 0.864,respectively (Z=7.210,7.430,P＜0.05).The accuracy of group A1 was poor.The area under the ROC curve was 0.626 (Z=2.434,P＜0.05).The sensitivity of group B and groupA2 were 80％ and 76.2％,respectively (P＜0.05),and 28.6％ of group A1 (P＜0.05).Conclusions The 320-row single-cardiac periodic dynamic volume CT can effectively improve the image quality and the detection accuracy of the systemic-pulmonary circulation on CT,and reduce the radiation dose of the bronchial artery CT angiography.
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Objective To explore the anatomic positional relationship of bronchial artery(BA)with esophagus and main bronchus on 320-detector CTA.Methods Original and post-processed images of 142 patients were observed.Type,origin,opening direction of BA as well as its concomitant relationship with esophagus were recorded.The positional relationship of BA with main bronchus was also recorded by fusing the images of BA and bronchial tree together.Results In 122 patients,273 BA were identified (146 on the right and 127 on the left).Right BA mainly ran simultaneously along the right and posterior edge of the esophagus (49.3%),while left BA mainly ran far gradually on the left side of the esophagus (82.7%).The left and right BA mainly ran along the middle thoracic esophagus, accounting for 58.3% and 42.5% respectively.45.2% of the right BA ran across the posterior edge of the right main bronchus and 60.6% of left BA ran simultaneously on the posterior and up edge of the esophagus.The most dividing direction of BA from the tho-racic aorta was 9 to 12 o’clock with a frequency of 74.2%.Conclusion The concomitant relationship with esophagus of the BA and the positional relationship with main bronchus of the BA could clearly be demonstrated on 320-detector CTA,thus providing availa-ble information and help for pulmonary and mediastinal sugery.
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Objective To observe the effect of electroacupuncture in preventing delayed cerebral vasospasm (DCVS).Method Sixteen healthy Japanese big ear rabbits were randomized into a treatment group and a control group, 8 in each group. The treatment group was developed into models by intramuscular anesthesia on the 6th day after 5 days’ 20-min daily intervention of transcutaneous acupoint electrical stimulation during a specific time period; the control group was developed into models by the same way on the 6th day but without electrical stimulation. The diameter of basilar artery was measured by using CTA prior to the electrical stimulation and after modeling in both groups, the plasma levels of ET-1, CGRP, and IL-6 were detected, and behavioral changes 1 d, 3 d, and 5 d after modeling were observed.Result After modeling, there was a significant difference in comparing the basilar artery diameter between the two groups (P<0.05). The plasma levels of ET-1, CGRP, and IL-6 in the treatment group were significantly different from that in the control group (P<0.05). In the treatment group, the neural function scores 3 d and 5 d after modeling were markedly different from that 1 d after modeling (P<0.05). There were significant differences in comparing the neural function scores 3 d and 5 d after modeling between the two groups (P<0.05).Conclusion Pre-intervention with electroacupuncture prevents and improves DCVS possibly via modulating the levels of ET-1, CGRP, and IL-6, and subsequently involving in anti-inflammation, immune inhibition, and vasodilation.
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Objective To study the effects of two different methods of high-pressure injections on imaging quality of synchronous left axillary artery and vein by using volume CT.Methods Forty seven patients who underwent left axillary vein and artery CTA examination study were analyzed retrospectively according to the contrast agent injection scheme and was divided into two groups A and B.Group A of 25 patients used protocol A,adopted clinical routine delay scanning method,via right elbow vein inject contrast medium.Group B of 22 patients used protocol B,adopted artery delayed imaging combined with vein direct imaging method,via right elbow vein,left radial vein inject contrast agent,respectively.Both values of CT and contrast to noise ratio (CNR) of two groups were compared,objective image quality was compared by two blinded readers.Mann Whiteny U test was used.Results The median of CT values for left axillary artery in group A was 151.9 HU.The median of CNR values for left axillary artery in group A was 7.4.The median of CT values for left axillary vein in group A was 116.0 HU.The median of CNR values for left axillary vein in group A was 3.83.The median of CT values for left axillary artery in group B was 348.8 HU.The median of CNR values for left axillary artery in group B was 25.3.The median of CT values for left axillary vein in group B was 497.0 HU.The median of CNR values for left axillary vein in group B was 35.4.Both values of CT and CNR in two groups showed significant difference (Z=-5.735,-5.799,-5.863 and-5.863,P＜0.01).All of the median scores in group B were greater than in group A(P＜0.01).Conclusion The enhancement effect of protocol B in the left axillary arteriovenous synchronous imaging is significantly higher than those of protocol A,and demonstrates clear image quality and clearer anatomic relationship.
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Objective To evaluate the clinical value of 320-detector CT in interventional treatment of bronchial artery hemoptysis. Methods CTA and DSA images of 30 patients with bronchial artery hemoptysis were retrospectively analyzed.Spatial anatomical characters of the bronchial arteries,such as the type of branches,origin and opening positions of the bronchial arteries were observed and recorded.Results In 30 patients,6 bronchial arteries distribution patterns were found,and the most common type was R1 L1 (43.3%).83 bronchial arteries were identified using CTA,including 38 on the right and 45 on the left.The right bronchial arteries mainly originated from the intercostal artery (52.6%),while the left bronchial arteries mainly from the descending aorta and aortic arch (82.2%).The opening positions of right and left bronchial arteries were mainly located at the right wall of the descending aorta (78.9%),and anterior wall of the descending aorta (62.2%),respectively.When the cacarina of trachea was used as the reference position,the left and right bronchial arteries were mainly located in the range of above 2 cm to below 1 cm from tracheal bifurcation, accounting for 80% and 89.5%,respectively.Compared with DSA,the sensitivity and specificity of CTA were 97.5% and 100%, respectively.Conclusion 320-detector CT can be used to clearly display the distribution patterns,origin and opening positions of bronchial arteries,and especially to find bronchial arteries with ectopic origin.It is possible to apply 320-detector CT in preoperative routine examination and postoperative evaluation of massive hemoptysis.