- Assessing effects of low-dose CT attenuation correction on quantification and image quality on a LAFOV PET system with a modified NEMA-IQ phantom. [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: Even for low-dose CT protocols, PET quantification remained consistent in all NEMA-IQ spheres for many materials. Beam hardening and photon starvation in the CT image are likely to occur in specific body regions such as hips, shoulders or the abdomen for an arms-down scan and these effects had a bigger impact on the quantification than any difference in HU in both soft tissue and bone. This therefore should be considered when selecting suitable CT imaging parameters.
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- Gaussian process regression of HDR prostate biopsy dose for improved modelling of localization-induced uncertainty. [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: Along-core dose interpretation after localization uncertainty should use a spatially correlated model rather than separate voxelwise summaries alone. This Gaussian process framework provides a covariance-informed posterior dose representation with held-out internal validation and offers a practical basis for biopsy-level probabilistic quality assurance and future dose-response analyses.
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- Analysis on radiation protection of FLASH treatment in conventional proton therapy facilities. [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: The results indicate that, under existing conventional shielding conditions, the radiation risk posed to the environment outside the treatment room by FLASH irradiation using the Varian ProBeam proton therapy system is safe and controllable, and the annual occupational radiation dose for radiation workers is well below the annual dose equivalent limit. This provides important radiation safety justification for the clinical implementation of FLASH technology in existing proton therapy facilities.
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- A cell-type resolved proton RBE model for potential clinical application. [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: The variation of βX, which represents a cell's repair capability for critical damages, mainly contributes to RBE's cell-type dependence. A cell-type resolved model agreeing well with experimental data has been established.
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- Spot size reduction and minibeam creation in a proton PBS nozzle using multipole permanent magnets. [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: The proposed PBS nozzle could potentially be used to produce pencil beams and modulated beams with smaller spot sizes and penumbras, including proton minibeams, suitable for clinical or preclinical applications.
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- Development and evaluation of X-ray lithophanes as test objects for interventional procedure simulation. [Journal Article]
- CONCLUSIONS: Lithophane plates present an easy-to-implement solution to recreate monoplane x-ray scenes, which can be deployed to test software at the point of care with minimal logistical, ethical, or safety concerns. This study opens the door for a new range of interventional simulators able to recreate human-like appearance to test AI, offering a non-exclusive alternative to patient volunteers and anonymous data.
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- Regularization in multiplexed PET image reconstruction. [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: For the selected radionuclides, simulated system and phantom, we demonstrate proof-of-principle that using regularization applied to an alternating update form of EM achieves significantly higher CNR in both tracers compared to unregularized alternating update OSEM and regularized simultaneous OSEM, with significantly lower crosstalk in the prompt gamma emitter reconstruction than the regularized simultaneous OSEM.
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- Task-based detectability and angular-sampling bounds on spatial resolution in cone-beam micro-CT: a closed-form scan-design analysis. [Journal Article]
- CONCLUSIONS: The two reconstruction-independent limits combine into a usable engineering picture for scan design and detectability prediction in preclinical cone-beam micro-CT. The photon-noise limit is a task-based detectability threshold for a specified feature and contrast, expressed in frequency units rather than as a Fourier cutoff, and the combined map is a practical summary of these two independent, necessary constraints. Reconstructions that incorporate strong signal priors may exceed the Crowther limit at the cost of relying on those priors, but cannot exceed the photon-noise limit at any cost. An accompanying open-source interactive web calculator (https://ubc-ford-lab.github.io/ideal_observer_SKE_BKE_model/) implements these bounds for arbitrary scanner geometries.
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- A generalizable 3D dose prediction across heterogeneous cohorts: A framework developed for the 2025 AAPM GDP-HMM challenge. [Journal Article]
- CONCLUSIONS: We present a generalizable 3D dose prediction framework that achieves state-of-the-art accuracy while satisfying stringent runtime requirements (< 3s per case on < 24 GB GPU memory). By integrating gradient-aware and moment-based constraints within a MedNeXt backbone, the model preserved clinical DVH endpoints and geometric plan features. These findings demonstrate that carefully engineered loss formulations are pivotal for cross-institutional generalization. The framework offers a foundation for rapid dose prediction that could accelerate treatment planning, reduce inter-planner variability, and enable intelligent automation in radiotherapy workflows.
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- Can we assess brain perfusion on a regional basis from digital subtraction angiography images with motion artifacts? [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: MCI-D enables accurate motion-compensated perfusion assessment from DSA images, even in the presence of severe motion artifacts, provided that the motion is not continuous and occurs within a short period of time.
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- Low latency and generalizable dynamic MRI via L+S alternating gradient descent and minimization. [Journal Article]
- CONCLUSIONS: Our AGM-L+S-FS approach provide generalizable, fast, and low-latency MRI reconstruction across multiple dynamic MRI applications and sampling schemes, without the need for problem-specific parameter tuning.
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- Influence of forehead gap size on eye protection provided by lead eyewear worn over prescription glasses: A Monte Carlo study. [Journal Article]
- CONCLUSIONS: By quantifying the relationship between the size of the lens gap and shielding rates, this study estimates the protective effects of fit-over eyewear and can help IR physicians select suitable eyewear. Our findings show that fit-over eyewear with bottom shields effectively protects the left eye during posterior-anterior projection. Although introducing bottom shields can improve conventional side-shield models in terms of increased shielding rate for the left eye, the shielding rates for the right eye remained low because of the gap around the nose. Further study of new designs with a shielded covering over the nose may be warranted.
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- Low-dose CT denoising using a diffusion prior via score distillation sampling. [Journal Article]Med Phys. 2026 Nov; 53(11).MP
- CONCLUSIONS: The results show that diffusion-based image priors can be leveraged across various low-dose levels within the proposed optimization-based denoising framework. Our work suggests that SDS-guided diffusion priors are a promising direction for LDCT denoising in data-limited settings.
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- Model-based image restoration targeting higher-dose digital mammography: Impact on radiologists' detection of clustered microcalcifications. [Journal Article]
- CONCLUSIONS: The proposed extended MB restoration pipeline improved the detectability of simulated microcalcification clusters by breast radiologists under the controlled 4AFC conditions investigated. By targeting the signal and noise characteristics predicted by the model for an acquisition at approximately twice the original radiation dose without requiring additional radiation exposure, the method represents a promising approach for improving microcalcification detectability in DM.
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- DoseRAD2026: A benchmark dataset for AI-accelerated photon and proton dose calculation in radiotherapy. [Journal Article]
- CONCLUSIONS: The DoseRAD2026 dataset enables benchmarking and development of fast dose calculation methods for radiotherapy applications. Potential use cases include rapid beam-level dose estimation for photon and proton therapy, MRI-based dose calculation in MRI-only and MRI-guided radiotherapy workflows, and support for real-time adaptive radiotherapy strategies.
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