论文部分内容阅读
PURPOSETo evaluate the image quality, detection rate and radiation dose for prospectively ECG-triggered high-pitch coronary CTA with 32 mL contrast media scanned at 70 kVp. METHOD AND MATERIALS58 patients with suspected coronary artery disease (BMI<26 kg/m2, sinus rhythm and HR<70 bpm) were prospectively enrolled in this study. All patients underwent prospectively ECG-triggered high-pitch coronary CTA on dualsource CT system at 70 kVp using automated tube current modulation. Patients with HR<70bpm were imaged at 60% of the R-R interval. Contrast media injection protocol was fixed for all: 32 mL of370 mg I/mL iodinated contrast media administrated at a flow rate of 3 mL/s. Main coronary artery CT value, SNR and CNR to adjacent fat tissue were evaluated. Subjective evaluation was also performed based on AHA 15 segment model using 4-point grading scale. RESULTSCT values for interested main arteries were all above 350HU which meet the requirement of diagnoses. By virtue of advanced iterative reconstruction algorithm, SNR and CNR for main coronary arteries were also high compared with previous peers result (SNR: 28.92±12.50, CNR: 26.03±11.00). Subjective evaluation indicated that 96.6% (56/58) patient images were graded as diagnosable, 82.8% (48/58) patients images were graded as excellent. Per-segment study showed that 98.9% (876/885) of segments were acceptable. The average score over all segments were 3.82±0.40. No significant image quality difference was found between low HR group and high HR group and the mean effective radiation dose was 0.36±0.12 mSv. CONCLUSIONProspectively ECG-triggered high-pitch coronary CTA at 70 kVp with 32 mL of contrast media can provide promising image quality at a radiation dose less than 0.4mSv for normal-weight patients. CLINICAL RELEVANCE/APPLICATIONThe proposedprotocol is a suitable option to exclude CVD if radiation dose or contrast media toxicity is a concern.