arXiv AI

Generalizable dose denoising using diffusion transformer framework for pencil beam scanning proton therapy

A diffusion‑transformer framework was developed to denoise low‑statistics Monte Carlo dose distributions for intensity‑modulated proton therapy. Trained on 80 head‑and‑neck patient datasets, the model was evaluated on 10 additional head‑and‑neck cases and 30 patients with lung, breast, and prostate cancers, achieving mean absolute errors of 0.08–0.20 Gy and 3 %/2 mm gamma passing rates above 95 %. The denoised dose maps closely matched high‑statistics reference distributions in dose‑volume histogram metrics for clinical targets and organs at risk.

arXiv Machine Learning
Jul 15

GenDiff: A Dose and Anatomy Aware Diffusion Model with Structural Prior Refinement for Low-Dose CT Reconstruction and Generalization

arXiv:2607. 11941v1 Announce Type: cross Abstract: Computed tomography (CT) is a critical imaging modality for clinical diagnosis, but reducing radiation dose inevitably introduces severe noise and structured artifacts that degrade image quality.

By Md Imam Ahasan, Guangchao Yang, A F M Abdun Noor, Kah Ong Michael Goh, S. M. Hasan Mahmud, Md Mahfuzur Rahman
arXiv AI
Sep 17

Dose-Aware Cold Diffusion with Physics Consistency for Generalizable Low-Dose CT Reconstruction

The paper introduces Dose-Aware Cold Diffusion (DACD), a physics-consistent framework that treats radiation dose as a continuous latent variable in a cold diffusion process for low-dose CT reconstruction. DACD combines dose-aware perception, multi-scale structural priors, and dose-calibrated step allocation to guide denoising, and adds an iterative forward-backprojection correction to enforce projection-domain consistency. Experiments on Mayo-2020, Mayo-2016, and LoDoPaB-CT show DACD outperforms existing diffusion-based and physics-guided methods, especially at ultra-low doses, and generalizes robustly across continuous, unseen dose levels.

By Md Imam Ahasan, Guangchao Yang, A F M Abdun Noor, S M Hasan Mahmud, Md Mahfuzur Rahman
arXiv AI
Aug 11

Toward CT-Equivalent Image Quality in Low-Dose Radiotherapy Planning: Conditional Diffusion-Based CBCT-to-CT Synthesis and the Impact of CBCT Input Representation

arXiv:2608. 08919v1 Announce Type: cross Abstract: During standard radiotherapy planning, repeated CT acquisitions are often required for patient registration, verification, and adaptive planning, resulting in increased cumulative X-ray dose.

By Alzahra Altalib, Chunhui Li, Christopher Hamill Taylor, Sankar Pillai, Alessandro Perelli
arXiv Computer Vision
Aug 28

Parameter-Efficient pretrained-CT-to-MRI Transfer for Rectal Cancer Segmentation: Performance-Calibration Trade-offs

The paper introduces SWIFT, a Swin V2‑based model pretrained on 10,444 3D CT volumes and fine‑tuned for rectal cancer segmentation on T2‑weighted MRI. Four configurations—full fine‑tuning (SWIFT), decoder compression (SWIFTe), low‑rank adaptation (SWIFTe‑LoRA), and a LoRA‑decoder ensemble (SWIFTe‑LDE4)—were evaluated on 247 cases, showing that SWIFTe reduces parameters by 70.1% while improving tumor detection and radiomic agreement. The study also demonstrates a trade‑off between detection and boundary agreement, and highlights that SWIFTe‑LDE4 achieves the lowest calibration errors after temperature scaling.

By Aneesh Rangnekar, Jorge Tapias Gomez, Joseph O Deasy, Harini Veeraraghavan
arXiv AI
Oct 1

An Uncertainty-Guided Digital Twin Framework for Online Adaptive Proton Therapy in Head and Neck Cancer: A Feasibility Study

arXiv:2609.39010v1 Announce Type: cross Abstract: Objective: Head and neck (HN) proton therapy spans six to seven weeks of anatomical change, while offline replanning takes about a week. We present a...

By Yizhou Wu, Ryan J. Sanford, Huiqiao Xie, Jie Ding, Shupeng Chen, Tung-Ho Wu, Ping-Hsiu Wu, Justin Roper, Jun Zhou, Minglei Kang, Bill Stokes, Sibo Tian, David S. Yu, Xiaofeng Yang, Chih-Wei Chang
arXiv AI
6d ago

EPC-RawDC: Equivariant Physics Constrained 3D Diffusion with Raw Data Consistency for CBCT to CT Image Synthesis

EPC‑RawDC is a 3‑D latent diffusion model that synthesises CT images from CBCT scans by enforcing two physics‑based constraints: a geometry‑equivariant projection loss and raw data consistency using scan‑specific CBCT projections. Trained on two clinical cohorts with different scanner geometries, the method achieved SSIM of 0.97 and improved PSNR and MAE over a baseline DDPM, reducing projection and equivariant errors by 55 % and 41 % respectively.

By Alzahra Altalib, Chunhui Li, Alessandro Perelli
arXiv Computer Vision
Oct 27

End-to-end prostate lesion segmentation and detection from undersampled diffusion-weighted MRI

arXiv:2610.33554v1 Announce Type: new Abstract: Automated prostate lesion detection from diffusion-weighted MR imaging (DWI) conventionally relies on reconstructed images and does not fully use all a...

By Lukas T. Rotkopf, Marco Schlimbach, Kevin Kr\"{o}ninger, Stefan O. Schoenberg, Heinz-Peter Schlemmer, Jens Kleesiek, Moritz Rempe