Sim-Heng Ong

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Anisotropic diffusion (AD) has proven to be very effective in the denoising of magnetic resonance (MR) images. The result of AD filtering is highly dependent on several parameters, especially the conductance parameter. However, there is no automatic method to select the optimal parameter values. This paper presents a general strategy for AD filtering of MR(More)
RATIONALE AND OBJECTIVES A reliable and cost-effective method for osteoporosis screening is important in addressing the increase in osteoporotic fractures due to aging populations. Diagnostic computed tomographic (dCT) images may contain densitometric information useful for osteoporosis screening. The aim of this study was to investigate the relationship(More)
PURPOSE To evaluate the acceleration of pupil constriction (APC) in response to illumination using video anterior segment optical coherence tomography (AS-OCT) in angle closure and normal eyes. METHODS This was an observational study of 342 Chinese subjects. Iris and angle changes in response to illumination were captured with real-time video recordings(More)
Three-dimensional (3D) hepatocyte spheroids mimicking the structural and functional characteristics of hepatocytes in vivo were self-assembled onto a galactosylated polyethylene terephthalate (PET) substratum, and the dynamic process of spheroid formation was investigated using time-lapse confocal microscopy. Hepatocytes cultured on this galactosylated(More)
To evaluate the speed of pupil constriction (SPC) in response to a standardized change in illumination from dark to light using anterior segment optical coherence tomography (AS-OCT) in eyes with closed angles, compared to those with open angles. This was a prospective, comparative, observational study. Study subjects with primary angle-closure glaucoma(More)
OBJECTIVE To evaluate changes in the speed of pupil constriction and in anterior segment parameters after laser peripheral iridotomy (LPI) in patients with angle closure using anterior segment optical coherence tomography. METHODS In this prospective observational study, videos of pupil and anterior segment changes in response to illumination were(More)
In vertebroplasty, physician relies on both sight and feel to properly place the bone needle through various tissue types and densities, and to help monitor the injection of PMMA or cement into the vertebra. Incorrect injecting and reflux of the PMMA into areas where it should not go can result in detrimental clinical complication. This paper focuses on the(More)
PURPOSE Soft and hard tissue volumes are critical for implant placement and long-term stability. Although the literature has adequately addressed tissue biotypes of Western populations, pertinent information about Asian populations is limited. This study aimed to evaluate the soft and hard tissue profiles of the maxillary anterior teeth of the Taiwanese(More)
We present predictions for exclusive photoproduction of Φ-meson on proton at large transfer, where we use a quark-diquark structure model for the proton. Extrapolation from our results to lower transfers is comparable in magnitude with available data in that range. This may support the diquark model in its ability to provide, for that process, an(More)
The effect of coronary artery calcification on local plaque vulnerability remains unclear. The overall degree of coronary calcification, as visualized on angiography and quantified using coronary computed tomography, has been shown to correlate with total atherosclerotic burden and risk of adverse cardiac events. However, different patterns in the(More)