PT  - JOURNAL ARTICLE
AU  - J.M. Hoxworth
AU  - D. Lal
AU  - G.P. Fletcher
AU  - A.C. Patel
AU  - M. He
AU  - R.G. Paden
AU  - A.K. Hara
TI  - Radiation Dose Reduction in Paranasal Sinus CT Using Model-Based Iterative Reconstruction
AID  - 10.3174/ajnr.A3749
DP  - 2013 Oct 10
TA  - American Journal of Neuroradiology
4099  - http://www.ajnr.org/content/early/2013/10/10/ajnr.A3749.short
4100  - http://www.ajnr.org/content/early/2013/10/10/ajnr.A3749.full
AB  - BACKGROUND AND PURPOSE: CT performed with Veo model-based iterative reconstruction has shown the potential for radiation-dose reduction. This study sought to determine whether Veo could reduce noise and improve the image quality of low-dose sinus CT. MATERIALS AND METHODS: Twenty patients consented to participate and underwent low- and standard-dose sinus CT on the same day. Standard-dose CT was created with filtered back-projection (120 kV[peak], 210 mA, 0.4-second rotation, and 0.531 pitch). For low-dose CT, mA was decreased to 20 (the remaining parameters were unchanged), and images were generated with filtered back-projection and Veo. Standard- and low-dose datasets were reconstructed by using bone and soft-tissue algorithms, while the low-dose Veo reconstruction only had a standard kernel. Two blinded neuroradiologists independently evaluated the image quality of multiple osseous and soft-tissue craniofacial structures. Image noise was measured by using multiple regions of interest. RESULTS: Eight women and 12 men (mean age, 63.3 years) participated. Volume CT dose indices were 2.9 mGy (low dose) and 31.6 mGy (standard dose), and mean dose-length products were 37.4 mGy-cm (low dose) and 406.1 mGy-cm (standard dose). Of all the imaging series, low-dose Veo demonstrated the least noise (P < .001). Compared with filtered back-projection low-dose CT using soft-tissue and bone algorithms, Veo had the best soft-tissue image quality but the poorest bone image quality (P < .001). CONCLUSIONS: Veo significantly reduces noise in low-dose sinus CT. Although this reduction improves soft-tissue evaluation, thin bone becomes less distinct. Abbreviations BONE FBP LDbone algorithm, filtered back-projection, low doseBONE FBP SDbone algorithm, filtered back-projection, standard doseIRISiterative reconstruction in image spaceSAFIREsinogram-affirmed iterative reconstructionSOFT FBP LDsoft-tissue algorithm, filtered back-projection, low doseSOFT FBP SDsoft-tissue algorithm, filtered back-projection, standard doseVEO LDVeo model-based iterative reconstruction, low dose