Adaptive statistical iterative reconstruction versus filtered back projection in the same patient: 64 channel liver CT image quality and patient radiation dose
- 665 Downloads
To compare routine dose liver CT reconstructed with filtered back projection (FBP) versus low dose images reconstructed with FBP and adaptive statistical iterative reconstruction (ASIR).
In this retrospective study, patients had a routine dose protocol reconstructed with FBP, and again within 17 months (median 6.1 months), had a low dose protocol reconstructed twice, with FBP and ASIR. These reconstructions were compared for noise, image quality, and radiation dose.
Nineteen patients were included. (12 male, mean age 58). Noise was significantly lower in low dose images reconstructed with ASIR compared to routine dose images reconstructed with FBP (liver: p < .05, aorta: p < 0.001). Low dose FBP images were scored significantly lower for subjective image quality than low dose ASIR (2.1 ± 0.5, 3.2 ± 0.8, p < 0.001). There was no difference in subjective image quality scores between routine dose FBP images and low dose ASIR images (3.6 ± 0.5, 3.2 ± 0.8, NS).Radiation dose was 41% less for the low dose protocol (4.4 ± 2.4 mSv versus 7.5 ± 5.5 mSv, p < 0.05).
Our initial results suggest low dose CT images reconstructed with ASIR may have lower measured noise, similar image quality, yet significantly less radiation dose compared with higher dose images reconstructed with FBP.
KeywordsImage quality Low dose CT Adaptive statistical iterative Reconstruction Filtered back projection Radiation dose reduction
- 4.Marin D, Nelson RC, Schindera ST et al (2010) Low-tube-voltage, high-tube-current multidetector abdominal CT: improved image quality and decreased radiation dose with adaptive statistical iterative reconstruction algorithm–initial clinical experience. Radiology 254:145–153PubMedCrossRefGoogle Scholar
- 12.AAPM Task Group 23 of the Diagnostic Imaging Council CT Committee (2008) The Measurement, Reporting, and Management of Radiation Dose in CT [AAPM Report 96]. American Association of Physicists in Medicine College Park, MD. Available via http://www.aapm.org/pubs/reports/RPT_96.pdf. Accessed 04 January 2011