The Application Of Dual-energy Non Linear Blending Technique To Improve The Image Quality Of Coronary Artery CT Angiography

Objective To investigate the application value of non-linear blending(NLB)algorithm in improving the image quality on Dual energy Coronary CTA.Methods Total 56 cases of Coronary artery CTA with 100 kV data,140 kV data,Linear blending data and Non-linear blending data were collected with subjective image quality score of<3 and were reconstructed using the NLB technique.The row data and reconstructed images were divided into 4 groups,100 kv group,140 kv group,LB group,NLB group.The measure ROI were delineated at 8 places:Arch of aorta,Right Coronary Artery Near Segment,Right Coronary Artery Far Segment,Left Main Coronary Artery,Left Anterior Descending Artery Near Segment,Left Anterior Descending Artery Far Segment,Left Circumflex Artery Near Segment and Left Circumflex Artery Far Segment.The CT value,Noise(SD),SNR,CNR of each group were evaluated and compared.Results There was a significant difference in subjective image quality score between NLB group and LB group([2.57±0.59]vs[2.07±0.59]).The diagnostic rate and excellent rate of images in LB group and NLB group were 85.71%,21.43%and 94.64%,51.79%respectively.The subjective scores of the two radiologists had a better agreement(Kappa value=0.684).The CT value,SD and CNR values of the Coronary artery segments at 8 different ROIs of 100 kV,140 kV,LB group,and NLB group with the,=150 HU&ω=200 HU were statistically significant.However,SNR values of coronary artery segments with 8 different ROIs were not statistically significant in most of the ROIs.The difference in CT values between the groups was statistically significant,with result showing that,100 kv CTROI>NLB CTROI>LB CTROI>140 kv CTROI.There was a statistically significant difference between SD groups,with the result showing that,100 kv SD value>NLB SD value>LB SD value>140 kv SD,and the NLB left myocardium mass and background air SD were lower than 100 kV.The differences in CNR values among different ROIs in 100 kv,140 kv,LB group and NLB group were statistically significant.NLB group>100 kV group>LB group>140 kV group.However,differences in SNR values among different ROIs in 100 kv,140 kv,LB group&NLB group showed significant difference only in ROI of arch of aorta and Left Main Coronary Artery.In other segments with respect to SNR values,there were not statistically significant.Conclusion The NBL takes obvious advantages to improve the image quality of the coronary artery.