• Does Two-Segment Image Reconstruction at 64-Section CT Coronary Angiography Improve Image Quality and Diagnostic Accuracy?

    Christopher Herzog, MD Shaun A. Nguyen, MD, MA GiancarloSavino.MD Peter L. Zwerner, MD Josh Doll, MD Christopher D. Nielsen, MD Thomas G.FIohr, PhD Thomas J. Vogl, MD Philip Costello, MD U. Joseph Schoepf, MD

    Purpose: To prospectively evaluate the effect of single- versus two segment image reconstruction on image quality and diag nostic accuracy at 64-section multidetector computed to mographic (CT) coronary angiography by using conven tional coronary angiography as the reference standard

    Materials and Methods: The study design was approved by a human research com mittee; patients gave informed consent. The study was HIPAA compliant. Forty consecutive patients (22 men, 18 women; mean age, 61 years � 8 [standard deviation]) underwent both 64-section multidetector CT coronary angiography and conventional angiography. All data sets were reconstructed by using single- and two-segment image reconstruction algorithms, with resulting temporal resolution of 82.5-165 msec. Two experienced observers independently evaluated image quality and signs of coronary artery disease. A five-level grading scheme was used to grade stenosis (0%,

    Results: Six hundred coronary artery segments were visible on conventional angiograms, of which 560 (93.3%) were seen by using single-segment and 561 (93.5%) were seen by using two-segment image reconstruction (P = .35). Mean quality scores were not significantly different (P ~ .22) for single- (3.1 � 0.9) and two-segment (3.2 � 0.8) reconstruction. Significantly (P = .03) better image quality was observed for two-segment reconstruction only at heart rates of 80-82 beats per minute, at which temporal resolution was approximately 83 msec. For grading coronary artery stenosis, correlation was 0.64 for single- and 0.66 for two-segment reconstruction (P = .43). Significant stenosis (>50%) was detected on a per-segment basis with 77.1% sensitivity and 98.6% specificity by using single-segment and with 79.2% sensitivity and 99.1% specificity by using two-segment image reconstruction.

    Conclusion: At heart rates of more than 65 beats per minute, use of two-segment reconstruction improves image quality at multidetector CT coronary angiography but does not significantly affect overall diagnostic accuracy compared with single-segment