University of Pennsylvania

Prostate SBRT requires an expansion on the CTV to create the PTV. There is discussion over how large this expansion should be to adequately account for patient motion during treatment. A 3mm symmetric expansion of the CTV is beneficial for healthy tissue spar...

Automated treatment planning can reduce manual workload and improve consistency; however, supporting new clinical indications often requires development of dedicated tools rather than reuse of existing workflows. This study describes the creation of a central...

Enhanced Leaf Model (ELM) introduced in Varian Eclipse v18 has demonstrated improved commissioning efficiency and consistency with equivalent or superior dose calculation accuracy such as for HyperArc. This study investigated the feasibility of using ELM to c...

Spine SBRT involves steep dose gradients near critical organs at risk, making treatments highly sensitive to intrafraction motion. This study evaluated the performance of immobilization devices used for LINAC-based upper spine (T2 and above) SBRT by using mid...

Radiation-induced oral mucositis (OM) is a severe complication in head and neck cancer patients, significantly impacting quality of life. While Photobiomodulation (PBM) is a promising non-invasive management strategy, clinical protocols remain inconsistent re...

In vivo dosimetry is almost exclusively limited to surface or intracavitary sites and is generally unable to measure dose directly in deeper tumors or nearby critical structures. An injectable Fricke gel dosimeter has been developed to address this limitation...

Rectal spacers are widely used in prostate stereotactic ablative radiotherapy (SAbR) to reduce rectal dose; however, their value as a practical, planning-oriented QA tool remains underdefined. Using real-world clinical trial data, this study evaluates whether...

High-density metallic ports in breast tissue expanders (TE) introduce CT artifacts that cause dose calculation uncertainties for postmastectomy radiation planning. TE ports have either a titanium or stainless-steel needle guard and a very high-z magnet. Mater...

Cherenkov imaging enables non-invasive, real-time visualization of superficial dose during radiation therapy. In TSET using the Stanford standing technique, dose uniformity is highly sensitive to daily patient positioning. This study aims to experimentally de...

To refine the photochemical dose–response relationship for single-fraction Photofrin-mediated PDT by relating modeled reacted singlet oxygen dose to long-term tumor control and by using multispectral singlet oxygen luminescence detection (MSOLD) as an indepen...

The clinical translation of ultra-high dose rate (FLASH) radiotherapy is hindered by an incomplete understanding of the physical parameter space required to optimize normal tissue sparing. This study utilizes a human bone marrow-on-a-chip (BMoC) platform to m...

To evaluate CT-derived longitudinal changes in regional lung function following definitive treatment with photon versus proton radiotherapy in patients with locally advanced non-small cell lung cancer (LA-NSCLC).

This study aims to investigate the develop ultra-high-dose-rate (UHDR) proton FLASH spatially-fractionated-radiation-therapy (FLASH-SFRT) irradiations on a compact proton synchrocyclotron for preclinical experiments.

Radiopharmaceuticals, Theranostics, and Nuclear Medicine

Therapy Physics

Carbon ion radiotherapy (CIRT) offers high LET and RBE for treating radioresistant tumors but suffers from biological dose inhomogeneity due to RBE uncertainties. Techniques like LET painting focus on optimizing LET but do not directly address biological effe...

To develop a computer-aided diagnosis (CAD) system for the classification of benign versus malignant findings on 18F-PSMA PET/CT imaging. It was applied in patients with biochemical recurrent (BCr) prostate cancer (PCa), using post-therapy follow-up (FU) imag...

Proton conformal FLASH radiotherapy must simultaneously satisfy clinical dosimetric goals and deliver ultra-high-dose-rates under machine constraints. This highly coupled optimization problem is currently addressed through manual trial-and-error, limiting pla...

Current registration tools lack mechanisms for specifying clinical priorities. We developed a system accepting plain-text instructions (e.g., "prioritize tumor alignment for dose accumulation") and evaluated whether text guidance produces reliable, structure-...

Proton pencil-beam scanning (PBS) FLASH radiotherapy requires dosimetry systems capable of accurate and reliable operation under ultra high dose rate (UHDR) conditions. Faraday cups (FC) and multi-layer Faraday cups (MLFC) are dose-rate-independent charge col...

A proton conformal FLASH radiotherapy system was developed to generate spread-out Bragg peaks at tumor targets utilizing beam-modifying devices, consist of conformal energy modulator(CEM), range shifter(RS) and brass aperture(BA). The system delivers scanned...

This study develops an integrated framework combining three-dimensional deformable image registration with reactive oxygen species ([ROS]rx) modeling for comprehensive dosimetry in pleural photodynamic therapy (PDT). We aim to address clinical measurement gap...

Portal hypertension (PH) is currently diagnosed by the hepatic venous pressure gradient (HVPG). Subharmonic imaging (SHI) is a contrast-enhanced ultrasound (CEUS) imaging technique receiving at half the transmit frequency resulting in better tissue suppressio...

Manual segmentation of immunohistochemical (IHC) stained images is a time-consuming task that typically takes 1-2 workdays to segment all images needed for analysis. Deep learning-based methods were employed to create an AI model to automatically segment IHC...

Rectal gas variability introduces density heterogeneities that may compromise dose robustness in rectal proton therapy and affect bladder and bowel dosimetry. This study evaluates the impact of rectal gas variability on target coverage and critical organ-at-r...

Singlet oxygen (SO) is the primary cytotoxic agent in photodynamic therapy (PDT); however, real-time measurement of SO during treatment remains challenging. The purpose of this study is to investigate the dependence of SO signal on tissue oxygenation and trea...

Cherenkov imaging is a promising technique for visualizing and quantifying surface dose in radiation therapy. However, the absolute relationship between surface dose and emitted Cherenkov photons remains uncertain and varies with beam and tissue conditions. T...

Photon-counting CT (PCCT) incorporates detector technology that supports quantitative imaging in routine diagnostic evaluation by reducing scanner- and patient-specific effects, thereby enabling more reliable material quantification and characterization. Prev...

To investigate whether physics-based radiomics standardization can increase agreement in radiomics extracted from radiologist-annotated regions of diffuse lung disease (DLD) phenotypes across CT reconstruction kernels and radiation doses.

To develop and validate an agentic AI framework using Model Context Protocol (MCP) that enables clinicians to control CT-MR image registration through natural language guidance. The study aims to determine if text-based clinical intent produces predictable, s...

Time-resolved singlet oxygen luminescence detection (TSOLD) enables direct measurement of singlet oxygen generation during photodynamic therapy (PDT), while multispectral SOLD (MSOLD) and singlet oxygen explicit dosimetry (SOED) provide complementary cumulati...

While phantom studies demonstrate high spatial accuracy for Surface-Guided Radiation Therapy (SGRT) systems, validation with live human subjects is critical. Non-rigid facial motion and the lack of a concurrent motion reference standard present unique challen...

Cardiotoxicity remains a major concern in thoracic radiotherapy. Prior studies have associated whole heart (WH) and substructure dose-volume histogram (DVH) metrics with cardiac events; however, changing practice (e.g., immunotherapy consolidation, advanced t...

In Total Skin Electron Therapy (TSET) using the Stanford technique, the delivered dose is strongly affected by daily positioning uncertainties. This study presents an integrated framework that combines AI-assisted rapid generation of patient-specific six-post...

Cherenkov imaging has emerged as a promising technique for real-time dosimetry during external beam radiation therapy (EBRT); however, quantitative conversion of Cherenkov signal to delivered radiation dose remains challenging. The purpose of this study is to...

Prostate cancer male reproductive system malignancy and the most common male cancer treated by radiation. Given the high incidence rate and complexities of treatment planning, artificial intelligence (AI) solutions in medical physics are essential to reducing...

Therapy Physics

This work offers a comprehensive review of the progress made by the most populous countries in Latin America toward the professional recognition of medical physicists, covering their approaches to education and training, regulatory advances, and gender equity.

Therapy Physics

Radiation-induced damage to circulating lymphocytes is increasingly recognized as a critical determinant of both normal tissue toxicity and antitumor immune responses. Differences in radiation delivery time between proton conventional and FLASH dose rates may...

Proton minibeam radiation therapy (pMBRT) reduces normal tissue toxicity while preserving tumor control through spatial dose fractionation. However, multi-slit collimators (MSCs) substantially increase monitor unit requirements and delivery times, limiting cl...

Diagnostic and Interventional Radiology Physics

As artificial intelligence becomes increasingly integral to clinical oncology and clinical trials, medical physicists are uniquely positioned to lead the development of the robust system architectures required to integrate AI safely and effectively. This sess...

Clinical Trials Specialty Program

Therapy Physics

Diagnostic and Interventional Radiology Physics

Professional

Diagnostic and Interventional Radiology Physics

Patient motion estimation is essential for various X-ray imaging applications, and is typically formulated as an optimization problem. Solution using gradient-free methods often suffer from limited accuracy and high computational cost. Gradient-based approach...

Therapy Physics

To design and validate a phantom capable of remote temporal and point dose rate assessment for electron and proton FLASH beams, with integrated spatial information to enable full end to end verification.

On-board kV imaging systems on proton therapy machines predominantly rely on scintillator-based energy-integrating detectors (EIDs) for planar imaging and cone-beam CT (CBCT). However, EID-based CBCT is limited by suboptimal image quality and insufficient qua...

Clinical Trials Specialty Program

Leadership

Therapy Physics

Clinical Trials Specialty Program

Accurate evaluation of near-wall hemodynamic metrics, i.e. wall shear stress (WSS), time-averaged wall shear stress (TAWSS), and oscillatory shear index (OSI), is critical for understanding vascular disease progression. These indices depend on spatial derivat...

Automatic treatment planning and physician’s plan preference quantification are both critical tasks in High-dose-rate brachytherapy (HDRBT) of cervical cancer for rapidly generating high-quality plans meeting physician’s intent. This study employs inverse dee...

IM-CT

This session will present three of the most recently published or approved for publication Task Group or Scientific Reports under the Therapy Physics Committee. These report have not been presented before to the membership. These documents have already been r...

Therapy Physics

Task Group (TG) reports are without any doubt one of the most important scientific deliverables of the AAPM. The number of TG reports especially under Therapy Physics Committee (TPC) has exponentially increased the last few year. However, challenges and compl...

In this work, we experimentally commissioned proton spatially-fractionated-radiotherapy (pSFRT) clinical treatments on a compact proton synchrocyclotron. This involved an initial assessment of proton small-field dosimetry calculation accuracies with comprehen...

IM-CT

Diagnostic and Interventional Radiology Physics

RapidArc Dynamic (RAD) is a novel treatment delivery technique that combines rotational arc therapy with static angle modulated ports (STAMPs). This study evaluates the feasibility, dosimetric performance, and delivery efficiency of RAD for single-isocenter m...

Therapy Physics

Radiation oncology is undergoing a transformative shift with the emergence of novel modalities that challenge traditional paradigms of dose delivery and biological response. This symposium will explore three cutting-edge approaches—Spatially Fractionated Radi...