ABSTRACT
Objective To evaluate the clinical application of regulating bone removal ratio in dual-energy cerebral subtraction angiography.Methods A total of 45 patients who underwent two phases dual-energy CT angiography (CTA) were recruited and divided into several groups by the value of bone removal ratio,as follows: group A (Ratio=1.6), group B (Ratio=1.7), group C (Ratio=1.8) and group D (Ratio=1.9,default), as well as group E (100kV Neuro-DSA).The image quality of dual-energy CTA was evaluated by double blind method according to bone suppression and integrity of the vessel lumen (1-5 points, 1=poor, 5=excellent, 3-5=satisfactory).The bone removal ratio dependence of the image quality was analyzed using the self-control method.Moreover,the signal-to-noise ratio (SNR),contrast-to-noise ratio (CNR) and image scores were compared with the Neuro-DSA subtraction among these groups.Results The overall satisfaction of basis cranii images that were executed by dual-energy CTA with different bone removal ratios was listed as below: group A 73.33%, group B 91.11%, group C 78.52%, group D 70.37%.The satisfaction of siphon segment and petrous segment reached the maximum when the value of ratio was 1.7,and with significantly difference (P0.05).Conclusion With optimal bone removal ratio,the single enhanced dual-energy subtraction image quality with flash dual-source CT is consistent well with that of conventional 100 kV Neuro-DSA subtraction.Thus,this method is recommended in clinical emergency cerebrovascular examination for the improved image quality,which can compensate the shortage of vascular defect in basis cranill.
ABSTRACT
Objective To assess the feasibility of double phase subtraction angiography with second generation (128-slice )dual-source CT in low dose Flash spiral scan mode for the evaluation of cerebral vessel,compared with dual-energy subtraction angiogra-phy.Methods 60 patients underwent double phrase CT angiography were divided into group A (n = 30,with Flash spiral scan mode),group B(n=30,with dual-energy scan mode).The signal-to-noise ratio(SNR),the contrast-to-noise ratio(CNR)and the av-erage radiation of double phrase subtraction images were measured in two groups,respectively.The double phase subtraction images quality were graded by 2 independent readers on a 5-point scale(5=excellent)in double-blind,according to various degrees of the re-sidual bones,the vessel displayed and luminal integrity,respectively.Differences between two groups were analyzed by Mann-whit-ney test and t test.Results The double phrase image SNR showed no difference to both two groups(P >0.05).The image CNR of arterial and venous phase in group A were higher than that of group B(40.89±8.89 and 40.27 ±9.90 in group A vs 35.28 ±8.43 and 34.89±8.66 in group B;P 0.05).The vessel image scores of arterial phase were higher in group A than that of group B(4.93±0.25 vs 3.87±0.97;P <0.05).Some internal carotid in the base of skull has not good luminal integrity in group B.The mean dose length product (DLP)in group A was lower than that of group B,with a 39 percent reduction[(226±5.69 )mGy/cm vs (368 ± 21.35 )mGy/cm,P < 0.05 ].Conclusion With the roughly similar image quality to dual-energy double phase subtraction angiography,the cerebral vessels can be assessed using dual-source CT subtraction angiography in Flash spiral scan mode and a lower radiation dose.
ABSTRACT
AIM: To develop a method to detemine pinostrobin in Weitengning Talets (Lindera reflexae Hemsl.) by HPLC. METHODS:A C_(18) column was used,methyl alcohol-water(80∶20) was used as a mobile phase and the wavelength of UV detector was set at 290 nm. RESULTS:The linearity of this method was good with the average recovery of 97.9%,RSD was 0.74%(n=5). CONCLUSION:The methed is simple,reliable,sensitivity,and with good reproducibility.It can be used in quality control of Weitengning Tablets.