CT arthrography: in vitro evaluation of single and dual energy for optimization of technique.
The purpose of this study was to optimize CT arthrography technique and determine if dual energy CT (DECT) can provide any benefit over single energy CT (SECT). Iodinated contrast attenuation at different concentrations was measured using DECT and SECT at different beam energies (140, 120, and 80 kVp). Dose and noise were measured on phantoms at different tube currents. Three bovine femoral condyles with artificially created cartilage defects were scanned with dose-equivalent protocols. Contrast-to-noise ratio (CNR) between cartilage and iodine was measured, and the appearance of cartilage defects was graded by two readers. DECT scans were post-processed for iodine quantification. The beam energy 80 kVp had the highest iodine signal, 50% greater than DECT, 75% greater than 120 kVp, and 100% greater than 140 kVp. Noise was nearly identical for all techniques when dose was matched. The 80 kVp level had the highest CNR, 25% higher than 120 kVp and DECT, and 33% greater than 140 kVp. The 80 kVp technique was also preferred by both readers. DECT iodine quantification was significantly limited by the post-processing application, noise, and beam hardening. In this in-vitro study, the SECT 80 kVp CT arthrography technique was superior to currently performed 120 and 140 kVP SECT techniques and DECT.
Subhas
Naveen
N
Cleveland Clinic, Cleveland, OH 44195, USA. subhasn@ccf.org
Freire
Maxime
M
Primak
Andrew N
AN
Polster
Joshua M
JM
Recht
Michael P
MP
Davros
William J
WJ
Winalski
Carl S
CS
D000818:Animals; D001175:Arthrography / Q000379:methods*; D002102:Cadaver; D002417:Cattle; D003287:Contrast Media; D005272:Femur Neck / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D066298:In Vitro Techniques; D007472:Iohexol / Q000031:analogs & derivatives; D007719:Knee Joint / Q000000981:diagnostic imaging; D015588:Observer Variation; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media; D007472:Iohexol; C038192:iopromide