[The Minimum Values of (RR-PQ) for High Quality Coronary CT Angiogram in Half, Automatic Patient's Motion Correction (APMC) and Full Reconstruction Using 320-ADCT (0.275 s/r)].
BACKGROUND
A clear coronary CT angiography (CCTA) can be obtained when temporal resolution (TR) is shorter than slow filling (SF) duration. The SF duration was calculated by the following equation: SF=-443+0.742 (RR-PQ). Although, the TR of half and full reconstruction using 320-ADCT (0.275 s/r) are known, the TR of automatic patient motion correction (APMC) reconstruction is not clear. The purpose of this study is to clarify the each minimum value of (RR-PQ) for acquiring a clear CCTA that was made by half, full or APMC reconstruction.


METHODS
CCTA was performed in consecutive 345 (M/F=195/150, Age: 69±10 years) patients except for arrhythmia and the final heart rate (controlled by β-blocker) ≥80 bpm using 320-ADCT (Aquilion ONE, 0.275 s/r). In all subjects, 3 CCTAs were generated by half, full, or APMC reconstruction at the same optimal phase. Image quality (A: excellent, B: acceptable, C: poor) was estimated by the consensus of three trained researchers. We classified (RR-PQ) into 15 groups by each 50 ms interval.


RESULTS
The A or B % prediction (y) significantly correlated (y=-240.08+0.401x, r=0.98, p=0.0006 in half, y=-238.26+0.378x, r=0.98, p=0.0001 in APMC, and y=-236.84+0.332x, r=0.97, p<0.0001 in full reconstruction) with (RR-PQ) (x), respectively.


CONCLUSIONS
The minimum values of (RR-PQ) for 95% prediction of A or B image quality were ≥836 ms in half, ≥881 ms in APMC, and ≥998 ms in full reconstruction.
Department of Radiological Technology, Takase Clinic.
Tomoya
T
Takayanagi
Takako
T
Sekine
Takeshi
T
Kondo
Makoto
M
Amanuma
Tomonari
T
Sano
Kazumasa
K
Ishizaka
Hideyuki
H
Matsutani
Hitomi
H
Morita
Takehiro
T
Arai
Shinichi
S
Takase
D000368:Aged; D016477:Artifacts; D017023:Coronary Angiography / Q000379:methods*; D005260:Female; D006339:Heart Rate; D006801:Humans; D008297:Male; D009038:Motion; D014057:Tomography, X-Ray Computed / Q000379:methods*