Coronary Stent Imaging By Using High-Definition Model,Gemstone Spectral Imaging And Standard Scanning Model:A Phantom Study

Objective To evaluate the different energy levels of virtual monochromatic spectral(VMS) coronary stent image qualities at 60 bpm heart rate and to compare the stent’s inner diameter measurements by using high definition(HD)and gemstone spectral imaging( GSI). Methods Totally 5 different types of coronary stents(internal diameter: 3.10±0.55mm; strut thickness: 0.12±0.04mm) were placed in a pulsating cardiac phantom(ALPHA 1-VT PC, Fuyo Corporation, Japan). The stent phantom was scanned in 3 models: gemstone spectral imaging(GSI), spiral scan(S) and HD. All the spectral imaging data were analyzed by using GSI viewer to reconstruct the VMS images(60~140keV). Compare the image noise(N),signal-to-noise ratio(SNR)、 contrast-to-noise ratio(CNR)and inner diameter were measured on these 3 sequences of images. Results Compared with the lower keVthe,higher keV,S and HD showed the highest SNRs(P<0.05),while there were no significant differences in CNRs among VMS( 60 ~ 100keV), S and HD(P>0.05).The visible diameter(%) measurements of VMS had no significant differences among 60~140keV(P>0.05). The visible diameter(%)measurements of HD was significant higher than the other 2 scan models. Conclusion There was no significant differences in image quality among the 3 sequences of image. There was no significant differences in the inner diameter of coronary stent among VMS(60~100keV),at 60 bpm heart rate. Comparing to the GSI and S, HD showed a good agreement with the known inner diameter of coronary stent.GSI has significant advantages in reduce of the beam-hardening.