%0 Journal Article
%T Denoising Projection Data with a Robust Adaptive Bilateral Filter in Low-Count SPECT
%A Susumu Nakabayashi
%A Takashi Chikamatsu
%A Takao Okamoto
%A Tatsuro Kaminaga
%A Norikazu Arai
%A Shinobu Kumagai
%A Kenshiro Shiraishi
%A Takahide Okamoto
%A Takenori Kobayashi
%A Jun¡¯ichi Kotoku
%J International Journal of Medical Physics,Clinical Engineering and Radiation Oncology
%P 363-375
%@ 2168-5444
%D 2018
%I Scientific Research Publishing
%R 10.4236/ijmpcero.2018.73030
%X Low-count SPECT images are
well known to be smoothed strongly by a Butterworth filter for statistical
noise reduction. Reconstructed images have a low signal-to-noise ratio (SNR)
and spatial resolution because of the removal of high-frequency signal
components. Using the developed robust adaptive bilateral filter (RABF), which
was designed as a pre-stage filter of the Butterworth filter, this study was
conducted to improve SNR without degrading the spatial resolution for low-count
SPECT imaging. The filter can remove noise while preserving spatial resolution.
To evaluate the proposed method, we extracted SNR and spatial resolution in a
phantom study. </span><span style=\"font-family:Verdana;\">We also conducted paired comparison for
visual image quality evaluation in a clinical study. Results show that SNR
was increased 1.4 times without degrading the spatial resolution. Visual image
quality was improved significantly (p &lt; 0.01) for clinical low-count data.
Moreover, the accumulation structure became sharper. A structure embedded in
noise emerged. Our method, which denoises without degrading the spatial
resolution for low-count SPECT images, is expected to increase the
effectiveness of diagnosis for low-dose scanning and short acquisition time
scanning.
%K Bilateral Filter
%K Denoising
%K SPECT
%K Nuclear Medicine
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=86749