Evaluation of the image quality of integrated imaging in coronary combined with carotid and cerebrovascular computed tomography angiography

Abstract

Objective To evaluate the image quality, radiation dose and key technologies of integrated imaging in coronary combined with carotid and cerebrovascular computed tomography angiography (CTA), which hopes to offer a non-invasive imaging method for cardiovascular and cerebrovascular diseases evaluation. Methods A total of 493 symptomatic patients referred for simultaneous coronary, carotid, and cerebrovascular CTA were prospectively included. The subjects were divided into two groups according to CT model. Group A(300 cases), on which 3rd generation dual-source CT was performed, was further divided into groups A1(n=69, HR≤65 bpm) and A2(n=231, HR>65 bpm), while group B(113 cases), on which 2nd generation dual-source CT was performed, was further divided into groups B1(n=92, HR≤65 bpm) and B2(n=101, HR>65 bpm). Objective and subjective image quality and radiation dose were nalyzed, factors influencing image quality were determined, and the key technologies of the method were described. The measurement data were tested by independent sample t test, the frequency parameter composition ratio in the patient's clinical data was tested by chi-square χ2 test, and Cohen Kappa analysis was used to evaluate the consistency of the image quality score. Results (1) No statistically significant difference between groups A and B was found in terms of age (t=0.58, P=0.847), gender (χ2=1.45, P=0.228), and body mass index (t=1.20, P=0.277). (2) Objective evaluation of image quality: Common carotid artery, internal carotid artery, middle cerebral artery, and vertebral artery CT values and noise in group A were significantly lower than those in group B (t=1.98-4.49, all P<0.05), although no statistically significant difference between groups was found in terms of aortic root CT values (t=0.68, P=0.495) and noise score (t=0.31, P=0.755). (3) The consistency of the image quality assessment was good (Kappa value=0.912). ① Subjective evaluation of image quality: The average coronary CTA image quality score of group A was better than that of group B (t=0.018, P=0.001), and the rate of non-diagnostic coronary grade 4 vessels based on number of patients in group A was lower than that in group B (χ2=6.63, P=0.014). ② Carotid-cerebrovascular CTA score of group A was better than group B (t=0.013, P=0.004), and carotid-cerebrovascular grade 4 vessels were less likely to be diagnosed in group A than in group B (χ2=4.38, P=0.036). ③ The effective radiation dose of group A was significantly lower than that of group B[(1.48±0.33) mSv vs. (2.14±0.52) mSv; t=14.79, P=0.001]. Conclusions Integrated imaging by coronary and cerebrovascular CTA is a non-invasive imaging method which adopted different heart rates were captured by different scan time windows can providing high image quality with significant reduction of radiation for evaluation of coronary and cerebrovascular disease. Key words: Tomography, X-ray computed; Angiocardiography; Cerebral angiography; Image quality