Assessment of vertebral artery stents using 16-slice multi-detector row CT angiography in vivo evaluation: comparison of a medium-smooth kernel and a sharp kernel.
OBJECTIVE
To assess the lumen visibility of extracranial vertebral artery stents examined with 16-slice multi-detector row computed tomography (MDCT) angiography in vivo using a medium-smooth kernel (B30s) and a sharp kernel (B60s), and to compare these with digital subtraction angiography (DSA) after stent placement.


METHODS
Twenty stents from 20 patients (14 men, 6 women; mean age, 62.7+/-10.1 years) who underwent CT angiography (CTA) with 16-slice MDCT were retrospectively analyzed. In CT angiograms using a B30s and a B60s, the lumen diameters and CT attenuations of the stented vessels were measured three times by three observers, and artificial luminal narrowing (ALN) was calculated. To assess measurement reliability on CT angiograms, the intraclass correlation coefficient (ICC) was used. DSA served as the reference standard for the in-stent luminal measurements on CT angiography. The median interval between CT angiography and DSA was 1 day (range 1-10).


RESULTS
For interobserver reliability, intraclass correlation coefficients for the lumen diameters on CT angiograms with a B30s and a B60s were 0.90 and 0.96, respectively. The lumen diameters on CT angiograms using a B30s were consistently smaller than that on CT angiograms using a B60s (p<0.01). The mean ALN was 37+/-7% on CT angiograms using a B30s and 25+/-9% on CT angiograms using a B60s. The mean CT attenuation in in-stent lumen was 347+/-55HU on CT angiograms using a B30s and 295+/-46HU on CT angiograms using a B60s. The ALN and CT attenuation within the stented vessels between CT angiograms using a B30s and a B60s was significant (p<0.01).


CONCLUSIONS
16-slice MDCT using a sharp kernel allows good visualization of the stented vessels and is useful in the assessment of vertebral artery stent patency after stent placement.
Yoo
Won Jong
WJ
Department of Radiology, Holy Family Hospital, College of Medicine, The Catholic University of Korea, Wonmi-Gu, Bucheon, Gyeonggi, Republic of Korea.
Lim
Yeon Soo
YS
Ahn
Kook Jin
KJ
Choi
Byung Gil
BG
Kim
Ji Young
JY
Kim
Sung Hoon
SH
D000465:Algorithms; D000792:Angiography / Q000379:methods*; D001807:Blood Vessel Prosthesis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011856:Radiographic Image Enhancement / Q000379:methods; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015607:Stents; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome; D014711:Vertebral Artery / Q000000981:diagnostic imaging / Q000601:surgery; D014715:Vertebrobasilar Insufficiency / Q000000981:diagnostic imaging* / Q000601:surgery*