TY - JOUR
T1 - Image quality improvement using an image-based noise reduction algorithm
T2 - Initial experience in a phantom model for urinary stones
AU - Demehri, Shadpour
AU - Salazar, Pascal
AU - Steigner, Michael L.
AU - Atev, Stefan
AU - Masoud, Osama
AU - Raffy, Philippe
AU - Jacobs, Scott A.
AU - Rybicki, Frank J.
PY - 2012
Y1 - 2012
N2 - OBJECTIVE: To determine signal-to-noise (SNR), contrast-to-noise ratio, and segmentation error measurements in various low-dose computed tomographic (CT) acquisitions of an anthropomorphic phantom containing urinary stones before and after implementation of a structure-preserving diffusion (SPD) denoising algorithm, and to compare the measurements with those of standard-dose CT acquisitions. METHODS: After institutional review board approval, written informed consent was waived and 36 calcium oxalate stones were evaluated after CT acquisitions in an anthropomorphic phantom at variable tube currents (33-137 mA s). The SPD denoising algorithm was applied to all images. Signal-to-noise ratio, contrast-to-noise ratio, and expected segmentation error were determined using manually drawn regions of interest to quantify the effect of the noise reduction on the image quality. RESULTS: The value of segmentation error measurements using the SPD denoising algorithm obtained at tube currents as low as 33 mA s (up to 75% dose reduction level) were similar to standard imaging at 137 mA s. The denoised images at reduced doses up to 75% dose reduction have higher SNR than the standard-dose images without denoising (P < 0.005). Stepwise regression showed significant (P < 0.001) effect of dose length product on SNR, and segmentation error measurements. CONCLUSIONS: Based on objective noise-related image quality metrics, the SPD denoising algorithm may be useful as a robust and fast tool, and it has the potential to improve image quality in low-dose CT ureter protocols.
AB - OBJECTIVE: To determine signal-to-noise (SNR), contrast-to-noise ratio, and segmentation error measurements in various low-dose computed tomographic (CT) acquisitions of an anthropomorphic phantom containing urinary stones before and after implementation of a structure-preserving diffusion (SPD) denoising algorithm, and to compare the measurements with those of standard-dose CT acquisitions. METHODS: After institutional review board approval, written informed consent was waived and 36 calcium oxalate stones were evaluated after CT acquisitions in an anthropomorphic phantom at variable tube currents (33-137 mA s). The SPD denoising algorithm was applied to all images. Signal-to-noise ratio, contrast-to-noise ratio, and expected segmentation error were determined using manually drawn regions of interest to quantify the effect of the noise reduction on the image quality. RESULTS: The value of segmentation error measurements using the SPD denoising algorithm obtained at tube currents as low as 33 mA s (up to 75% dose reduction level) were similar to standard imaging at 137 mA s. The denoised images at reduced doses up to 75% dose reduction have higher SNR than the standard-dose images without denoising (P < 0.005). Stepwise regression showed significant (P < 0.001) effect of dose length product on SNR, and segmentation error measurements. CONCLUSIONS: Based on objective noise-related image quality metrics, the SPD denoising algorithm may be useful as a robust and fast tool, and it has the potential to improve image quality in low-dose CT ureter protocols.
KW - CT
KW - CT noise
KW - image quality
KW - structure-preserving diffusion algorithm
KW - urinary stone
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U2 - 10.1097/RCT.0b013e318262c7e2
DO - 10.1097/RCT.0b013e318262c7e2
M3 - Article
C2 - 22992614
AN - SCOPUS:84866712121
SN - 0363-8715
VL - 36
SP - 610
EP - 615
JO - Journal of Computer Assisted Tomography
JF - Journal of Computer Assisted Tomography
IS - 5
ER -