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RT Journal Article
SR Electronic
T1 Repeated Head CT in the Neurosurgical Intensive Care Unit: Feasibility of Sinogram-Affirmed Iterative Reconstruction–Based Ultra-Low-Dose CT for Surveillance
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1281
OP 1287
DO 10.3174/ajnr.A3861
VO 35
IS 7
A1 Corcuera-Solano, I.
A1 Doshi, A.H.
A1 Noor, A.
A1 Tanenbaum, L.N.
YR 2014
UL http://www.ajnr.org/content/35/7/1281.abstract
AB BACKGROUND AND PURPOSE: Patients in the neurosurgical intensive care unit undergo multiple head CT scans, resulting in high cumulative radiation exposures. Our aim was to assess the acceptability of a dedicated, special-purpose sinogram-affirmed iterative reconstruction–based ultra-low-dose CT protocol for neurosurgical intensive care unit surveillance head CT examinations, comparing image quality with studies performed with our standard-of-care sinogram-affirmed iterative reconstruction low-dose CT and legacy filtered back-projection standard-dose CT protocols. MATERIAL AND METHODS: A retrospective analysis was performed of 54 head CT examinations: ultra-low-dose CT (n = 22), low-dose CT (n = 12), and standard-dose CT (n = 20) in 22 patients in the neurosurgical intensive care unit. Standard-dose CT was reconstructed by using filtered back-projection on a Somatom Sensation 64 scanner. Ultra-low-dose CT and ultra-low-dose CT examinations were performed on a Siemens AS+128 scanner with commercially available sinogram-affirmed iterative reconstruction. Qualitative and quantitative parameters, including image quality and dose, were evaluated. RESULTS: Sinogram-affirmed iterative reconstruction ultra-low-dose CT represented a 68% lower dose index volume compared with filtered back-projection standard-dose CT techniques in the same patients while maintaining similar quality and SNR levels. Sinogram-affirmed iterative reconstruction low-dose CT offered higher image quality than filtered back-projection standard-dose CT (P &lt; .05) with no differences in SNR at a 24% lower dose index volume. Compared with low-dose CT, ultra-low-dose CT had significantly lower SNR (P = .001) but demonstrated clinically satisfactory measures of image quality. CONCLUSIONS: In this cohort of patients in the neurosurgical intensive care unit, dedicated ultra-low-dose CT for surveillance head CT imaging led to a significant dose reduction while maintaining adequate image quality. CTDIvoldose index volumeFBPfiltered back-projectionIRiterative reconstructionLDCTlow-dose CTNICUneurosurgical intensive care unitSAFIREsinogram-affirmed iterative reconstructionSDCTstandard-dose CTULDCTultra-low-dose CT