Publications by authors named "Ka Ki Lau"
Article Synopsis
- - This study explored the use of adaptive MR-guided stereotactic body radiation therapy (MRgSBRT) with a rectal spacer in treating localized prostate cancer, focusing on 1-year clinical outcomes from 34 patients.
- - Results indicated significant improvements in target coverage and reduced rectal toxicity in patients using the spacer compared to those who did not, with most side effects being mild and manageable.
- - The findings suggest that MRgSBRT combined with a rectal spacer is well-tolerated, as evidenced by stable patient-reported bowel health and low gastroinestinal side effects over a 1-year follow-up.
Background: The use of synthetic computed tomography (CT) for radiotherapy treatment planning has received considerable attention because of the absence of ionizing radiation and close spatial correspondence to source magnetic resonance (MR) images, which have excellent tissue contrast. However, in an MR-only environment, little effort has been made to examine the quality of synthetic CT images without using the original CT images.
Purpose: To estimate synthetic CT quality without referring to original CT images, this study established the relationship between synthetic CT uncertainty and Bayesian uncertainty, and proposed a new Bayesian deep network for generating synthetic CT images and estimating synthetic CT uncertainty for MR-only radiotherapy treatment planning.
A helical fan-beam kilovoltage computed tomography (kVCT) was recently introduced into Tomotherapy units. This study aims to share the initial experience of kVCT in clinical workflow, compare its performance with that of the existing megavoltage computed tomography (MVCT), and explore its potential in adaptive planning. We retrospectively enrolled 23 patients who underwent both MVCT and kVCT scans.
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- - This study investigates how different factors contribute to out-of-field doses (OFDs) in a 1.5 T MR-Linac, specifically examining phantom scatter, collimator scatter, and head leakage during both static fields and clinical intensity-modulated radiation therapy (IMRT) treatments.
- - Measurements were taken in a MR-conditional water phantom at various field sizes (5x5, 10x10, 15x15 cm) and depths, showing that collimator scatter consistently exceeds other types of scattering at distances of 100-400 mm, while head leakage remained the smallest contributor overall.
- - The results indicate that OFDs for IMRT vary with target size and significantly decrease for prostate SBRT treatment