Seminars

Weekly Seminar Series

Mondays, 4-5 p.m. | Health Sciences Learning Center

No Seminar December 2

WEBEX

Fall 2024 Seminar Series

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December 9 - Jonathan Mamou, PhD | Modern Applications of Quantitative Ultrasound for Biomedical Research

Modern Applications of Quantitative Ultrasound for Biomedical Research

Jonathan Mamou, PhD
Professor of Electrical Engineering in Radiology
Department of Radiology, Weill Cornell Medicine, New York, NY

Quantitative ultrasound (QUS) is an active research field focused on obtaining quantitative tissue properties (i.e., system- and user-independent) from ultrasound data. Conventional ultrasound imaging is commonly used to visualize soft tissue morphology. During scanning, a gray-scale B-mode image is displayed on screen from which a trained clinician can evaluate tissue states. However, B-mode ultrasound image formation discards valuable information in the raw backscattered echo signal that encodes information about tissue microstructure. Therefore, microstructural changes in soft tissues that accompany disease processes, but do not directly affect tissue morphology, may not be visible in B-mode images. QUS methods use the raw ultrasound data to reconstruct parametric maps that are representative of tissue microstructure. In this talk, I will review conventional ultrasound imaging and QUS methods based on analyzing the backscatter coefficient and envelope statistics. I will present recent in vivo results from lymph nodes (cancer), thyroids (cancer), and eyes (myopia). I will also briefly present results to improve and use quantitative acoustic microscopy systems used to image thin sections of tissues at ultra-high ultrasound frequencies (i.e., 250-1000 MHz).

November 25 - Hassan Rivaz, PhD | Optimizing Ultrasound with AI

Optimizing Ultrasound with AI: Physically-Inspired, Semi-Supervised, and Self-Supervised Learning for Efficient Aberration Correction and Beamforming

Hassan Rivaz, PhD
Professor & Concordia University Research Chair, Electrical and Computer Engineering

Ultrasound is a safe, fast, cost-effective, and portable imaging modality. With the introduction of pocket-sized, battery-powered ultrasound devices, it has the potential to become the modern-day stethoscope, providing clinicians with an accessible tool for critical patient insights. However, interpreting ultrasound images, which are often noisy, requires the expertise of trained clinicians. This presentation explores how advances in AI can simplify ultrasound interpretation by addressing two key areas: enhancing ultrasound image quality and extracting objective, quantitative tissue properties, such as tissue elasticity.

A significant challenge in training AI models for ultrasound analysis is the absence of ground truth in real ultrasound data. While simulated ultrasound images can be used, they often oversimplify the complexity of real-world conditions, leading to the domain shift problem, where model performance degrades on real test data. Additionally, even if ground truth could be estimated in real ultrasound data, variations in imaging settings, such as center frequency, further complicate model generalization. Our datasets frequently contain thousands of real ultrasound images, but without corresponding ground truth labels. In this talk, I will introduce methodologies based on self-supervision and unsupervised learning to unlock the value of these large, unlabeled datasets and address the challenges of domain shift and data variability in ultrasound imaging.

November 18 - Distinguished Professor Roger W. Howell | Radiopharmaceutical Therapy – How to Treat What You Cannot See

Radiopharmaceutical Therapy – How to Treat What You Cannot See

Roger W. Howell, PhD
Chief, Division of Radiation Research
Rutgers University

Radiopharmaceutical cocktails have been developed over the years to treat cancer. Cocktails of agents are attractive because one radiopharmaceutical is unlikely to have a curative therapeutic effect due to nonuniform uptake by the targeted cells. Therefore, multiple radiopharmaceuticals targeting different receptors on a cell and different degrees of diffusion into micrometastases is warranted. However, past implementations of radiopharmaceutical cocktails in vivo have not met with convincing results due to the absence of quantitative optimization strategies. We have developed artificial intelligence (AI) tools, within our recently released MIRDcell V4 application, that can optimize cocktails of radiopharmaceuticals. The AI tool determines the molar activities for each radiopharmaceutical in the cocktail that minimize the total disintegrations of the therapeutic radionuclide(s) that are required to achieve a specified tumor cell kill. Tools are provided for populations of cells that represent circulating or disseminated tumor cells, and for micrometastases. The capabilities of these tools will be demonstrated using both model and experimental data to show that this approach could be used to analyze samples of cells from cultures, animals, or patients to formulate the best combination of radiopharmaceuticals for maximum therapeutic effect with the least total number of disintegrations.

November 11 - Sjoerd J. Finnema, PhD | The Role of Imaging in CNS Drug Discovery and Development

The Role of Imaging in CNS Drug Discovery and Development

Sjoerd J. Finnema, PhD
Research Fellow
AbbVie

The discovery and development of central nervous system (CNS) drugs demand substantial resources, extended timelines, and significant costs, all entailing high risks. Positron emission tomography (PET) and magnetic resonance (MR) imaging have become indispensable tools in CNS drug development, facilitating decision-making in early-phase studies by assessing tissue exposure, target engagement, and pharmacological activity. As CNS drug development shifts towards disease modification, neuroimaging has emerged as a critical translational tool, optimizing the stratification of clinical trial participants and enhancing decision-making throughout the entire drug development process. In this seminar, we will explore various examples of how PET imaging plays a pivotal role in the CNS drug-development process.

November 4 - Bryan Muir, PhD | Reducing Uncertainty, Increasing Confidence: Ionizing Radiation Metrology at NRC

Reducing Uncertainty, Increasing Confidence: Ionizing Radiation Metrology at NRC

Bryan Muir, PhD
Research Officer (NRC), Adjunct Research Professor (Carleton University)
National Research Council Canada

The National Research Council is Canada’s largest research and technology organization, founded in 1916 to carry out applied research to address industrial and societal needs. A specific mandate of the NRC is to fulfil the role of Canada’s National Metrology Institute (NMI) and this is realized through NRC’s Metrology Research Centre. NRC Metrology is responsible for the realization of the international system of units (SI) and disseminates measurement standards through calibration and technical services to a wide range of end users.

The Ionizing Radiation Standards group within the Metrology RC is very active in addressing measurement issues in radiation protection, radiation therapy and industrial applications of ionizing radiation. Through i) the development of primary measurement standards for dosimetry, radioactivity and neutron fields, ii) the dissemination of these standards through calibrations, and iii) participation in research collaborations and best-practice guidance, it supports users across all applications of ionizing radiation to ensure that point-of-use measurements are accurate, traceable and equivalent.

This presentation will explore the history and mandate of the NRC, and describe the worldwide system of metrology that provides the basis for all measurements. I will describe activities in ionizing radiation metrology in Canada with a focus on research projects in linac dosimetry.

October 28 - Manojit Pramanik, PhD | Listening to light: Photoacoustic imaging and its applications

Listening to light: Photoacoustic imaging and its applications

Manojit Pramanik, PhD
Northrop Grumman Associate Professor
Iowa State University

Photoacoustic imaging is an emerging novel imaging technique combining both optical and ultrasound imaging. A short-pulsed laser illuminates the tissue to generate sound waves called the photoacoustic wave. These sound waves are used to get high contrast, high resolution deep tissue imaging of various parameters. Photoacoustic imaging, like ultrasound imaging, is a multi-scale multi-depth imaging modality.

In this presentation, the basics of photoacoustic imaging and several imaging systems will be covered. For example, photoacoustic computed tomography (PACT), photoacoustic microscopy (PAM). Few clinical/pre-clinical applications of photoacoustic imaging will be discussed, such as, non-invasive sentinel lymph node detection for breast cancer staging, intracranial hypotension detection in small animal, photoacoustic aided ultrasound-guided needle tracking etc. Recent development of deep learning applications in photoacoustic imaging and contrast agents will also be discussed.

October 21 - Abhishek Kumar, PhD | Optical Microscopy: Faster and Gentler Imaging

Optical Microscopy: Faster and Gentler Imaging

Abhishek Kumar, PhD
Assistant Professor
Cell and Regenerative Biology and Center for Quantitative Cell Imaging
UW-Madison

Optical imaging is widely used in biomedical sciences. Despite the wide range of optical imaging techniques available, there is no one universal modality suitable for all length scales and types of biological samples. Also, development of new optical imaging systems that can bridge existing gaps between cellular and organismal imaging is vital. Confocal and light sheet microscopes are two popular optical imaging modalities that are routinely used for imaging live and fixed samples at multiple spatial and temporal scales.

For the first portion of this talk, I will discuss our group’s efforts to advance these technologies for imaging large or rapidly growing samples at high spatial and temporal resolutions. Specifically, I will present our implementation of a confocal microscope for improving imaging speed by a few orders of magnitude for large samples. I will then show the use of this imaging technique, in collaboration with your colleagues, to answer important biological questions in systems ranging from living zebrafish embryos to whole cleared mammalian organs.

In the second half of my talk, I will discuss the computational tools we are developing and using to compliment imaging modalities. I will conclude by sharing our lab’s vision for the future and plan to integrate nanophotonics to augment imaging modalities.

October 14 - Jim Pipe, PhD | Combining Technology and Use Design for High Value MRI

Combining Technology and Use Design for High Value MRI

Jim Pipe, PhD
Professor of Radiology & Medical Physics
UW-Madison

Clinical MRI scanners were not designed de novo, but have their origin
in the NMR scanners used in laboratory science starting in the mid 20th century. The complexity of the equipment and the richness of the information that can be obtained makes MRI an incredibly useful diagnostic tool. However, some of this legacy includes unnecessary complications that pervade clinical MRI, which in turn can produce errors, image variability,
inefficiency, and poor access.

The Magnetic Resonance Technology and Use Design (MRTUD, pronounced “MR2D”) group at UW Madison produces next-generation MR technology with a strong emphasis on the interaction of the user. As we improve technical quality and efficiency, we embrace simplicity, operational clarity, conceptual models, and improved user experience. Examples of the technology we are designing, along with examples of the way in which strong design principles are applied, will be discussed. Our framework of “Value” will also be discussed, which is used as a guide for improving the impact our work on each individual patient as well as the global healthcare system in general.

October 7 - Jason Cai, PhD | Imaging synaptic vesicle protein 2A in the living brain

Imaging synaptic vesicle protein 2A in the living brain

Jason Cai, PhD
Associate Professor of Radiology & Biomedical Imaging
Yale School of Medicine

Extensive preclinical and postmortem data have shown that the brain region specific synapse loss is a robust biomarker of a variety of neurodegenerative diseases. Traditional techniques for quantifying synapses exclude their uses in the clinic, limiting their translation and direct clinical impact. PET imaging of synaptic vesicle protein 2A (SV2A) for the first time allowed us to quantify synapses in living systems noninvasively, opening up the possibility of using the spatial-temporal synapse density information in the early diagnosis of neurodegenerative diseases and the evaluation of treatment effects of novel therapeutics in the clinic.

In this presentation, we will talk about the development of SV2A PET ligands and their preclinical, translational, and clinical applications in neurodegenerative disorders.

September 30 - Aarushi Bhargava, PhD | Ultrasound and acoustic cavitation for therapy

Ultrasound and acoustic cavitation for therapy

Aarushi Bhargava, PhD
Assistant Professor, Department of Biomedical Engineering
University of Wisconsin-Madison

Although ultrasound is conventionally recognized as a diagnostic modality, it is emerging as a therapeutic strategy for various medical conditions. Ultrasound can non-invasively and wirelessly deliver thermal or mechanical energy via waves and induce cavitation to manipulate tissues and injected synthetic materials inside the body. This manipulation can be used for drug delivery and cell stimulation at low ultrasound intensities. At higher intensities, it can ablate tissues. In this talk, I will briefly discuss my research on using different acoustic cavitation regimes of microbubbles at varying intensities of focused ultrasound to treat retracted blood clots and alter dense fibrous environments at microscale levels. We will also be looking at the ability of ultrasound to stimulate synthetic microsystems for performing spatiotemporally controlled drug delivery and high-frequency cell-specific neurostimulation.

September 23 - Marty Pagel, PhD | The Infinite Game of Research

The Infinite Game of Research

Marty Pagel, PhD
Professor of Medical Physics & Radiology
University of Wisconsin-Madison

This presentation will discuss a variety of molecular imaging methods and research applications. We have developed MR Fingerprinting, PET/MRI, Photoacoustic Imaging (PAI) to quantitatively measure extracellular pH, oxygenation, and vascular transport rates in solid tumors. More recently, we have developed optical agents that detect extracellular proteases for eventual use during image guided surgery. We apply these molecular imaging methods to preclinical tumor models, and we have also applied our imaging methods to evaluate wound healing models.

Furthermore, this presentation will discuss the Infinite Game of research. Although biomedical research has often become a Finite Game in the USA, this type of game is unsustainable. Instead, a return to an Infinite Game of research has long-term benefits for our society, which can be accomplished by focusing on the fundamentals of the Infinite Game.

September 16 - John R. Cameron Symposium, Cynthia H. McCollough, PhD | Milestones in CT: Past, Present, and Future

Milestones in CT: Past, Present, and Future

Cynthia H. McCollough, PhD
Brooks-Hollern Professor of Medical Physics and Biomedical Engineering
Mayo Clinic, Rochester, MN

Since the first patient CT scan in 1971, CT technology has continued to improve, both in evolutionary and revolutionary ways. This presentation will describe the technical and clinical innovations that have occurred, including the introduction and clinical adoption of spiral, multi-slice, cardiac, dual-source, dual-energy, and photon-counting-detector CT. Reconstruction of images from the projection data has also undergone major changes, moving from filtered back-projection to iterative reconstruction and deep learning approaches. The consequences of these advances in technology include the ability to diagnose and monitor an ever-expanding list of clinical indications. Several of these will be highlighted in this tour of CT imaging.

September 9 - Student Demonstration Competition

Educational outreach is essential for increasing the visibility of medical physics and enticing the next generation of brilliant and motivated professionals. To encourage engagement with outreach efforts, the Medical Physics Graduate Student Outreach committee has worked with the Department of Medical Physics to offer scholarships for the creation of activities demonstrating interesting concepts in medical physics to non-expert audiences. After a short presentation detailing the current state of outreach in the Medical Physics program, each of the scholarship awardees will present their demonstrations. This seminar will be a fun and interactive opportunity to consider how we communicate our field’s value to the public.

Spring 2024 Seminar Series

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January 29 - Timothy P. Szczykutowicz, PhD | Clinical Medical Physics beyond scanner QA

Clinical Medical Physics beyond scanner QA

Tim P. Szczykutowicz, PhD
Associate Professor Departments of Radiology, Medical Physics, and Biomedical Engineering, University of Wisconsin-Madison

Are you uncertain about the future of diagnostic medical physics? I share this uncertainty and express skepticism regarding the sustainability of our field relying solely on government-regulated scanner quality assurance responsibilities for medical physicists. Furthermore, I observe that the ongoing AAPM Medical Physics 3.0 initiative is currently grappling with meeting genuine clinical needs. Similarly, our endeavors at Wisconsin sometimes face challenges in aligning with clinical requirements. The identification of projects that yield impactful changes to clinical workflow is nontrivial.
This presentation will delve into the research conducted at the University of Wisconsin-Madison, with a specific focus on clinical diagnostic medical physics. We will explore topics such as green radiology, patient throughput, examination quality, and protocol management and optimization. On the horizon is a forthcoming CMS quality measure set to take effect for the IQR (hospital inpatient quality reporting program), the OQR (hospital outpatient quality reporting program), and MIPS (physician reporting program). The metric embedded in this measure, developed at the University of Wisconsin, has the potential to serve as a mechanism for funding physicist time dedicated to quality projects beyond the traditional ‘scanner QA’ paradigm. We will examine what this CMS-motivated, quality-focused future could mean for our field.

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February 5 - Michael Speidel, PhD and Paul Laeseke, MD, PhD | Research Partnerships in the Image-Guided Interventions Lab

Research Partnerships in the Image-Guided Interventions Lab

Mike Speidel, PhD
Paul Laeseke, MD, PhD

The Image-Guided Interventions Lab (IGIL) is dedicated to the development and clinical translation of novel imaging and therapy techniques for interventional procedures. This mission requires close collaboration of investigators in Radiology, Medical Physics, and industry partners, as well as a flexible approach to R&D. In this presentation, the Co-Directors of the IGIL will share examples of collaborative projects that have evolved into federal funding, sponsored research, clinical trials, and university resources. Dr. Paul Laeseke (Interventional Radiology) will present on the development of CBCT-guided histotripsy therapy for liver cancer, and Dr. Michael Speidel (Medical Physics) will discuss the evolution of quantitative DSA and dual-energy DSA on an interventional C-arm platform.

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February 12 - Susanta Hui, PhD | Rediscovering the role of radiation in improving hematopoietic stem cell transplant outcomes for hematological diseases.

Rediscovering the Role of Radiation in improving hematopoietic stem cell transplant outcomes for hematological diseases.

Susanta Hui, PhD
Professor
Beckman Research Institute, Department of Radiation Oncology, City of Hope National Medical Center

Allogeneic hematopoietic cell transplantation (HCT) for hematological diseases has made improvements, but the issue of relapse/graft failure, graft-versus-host disease (GVHD), and other transplant-related toxicities remains unresolved. Our objective is to explore the potential of precision radiation to address these challenges through comprehensive clinical and pre-clinical studies, along with a multidisciplinary approach. I will provide a brief overview of the advances made in total marrow irradiation (TMI) and imaging technologies that have supported ongoing clinical trials and their outcomes. We will explore the potential radiobiological consequences of dose-escalated TMI on the bone marrow environment, which can affect donor homing, engraftment, and disease relapse. The results of these correlative studies led to the creation of two new radio-immunotherapy strategies to manage leukemia relapse and GVHD. I will inform you of the latest development on TMI-based HCT that can offer sustainable cures for sickle cell disease and maintain fertility and other organ functions.

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February 19 - Indra J. Das, PhD | Promises, Challenges, and Obstacles in MR-Linac

Promises, Challenges, and Obstacles in MR-Linac

Indra J. Das, PhD
Director of Medical Physics, Professor & Vice Chair, Northwestern Memorial Hospital, Northwestern Feinberg School of Medicine, Chicago

Multi-modality imaging has become the backbone of modern radiation treatment. MRI is preferably used due to different types of image acquisitions providing superior soft tissue contrast and high resolutions images without radiation. To use these images in radiation treatment, image-fusion is required with limited success. Emergence of combined technology, MRI and linear accelerator on a single gantry called MR-Linac eliminates image fusion issues and provides simultaneous seamless imaging and treatment. It is a nascent high performing technology integrating MRI unit and a linear accelerator on a single gantry providing promises for better outcome in radiation oncology. This technology has opened the window of opportunity for adaptive therapy that can be adjusted during each session, accounting for any changes in tumor size, shape, or position and offers motion management for many diseases. Due to complexity of the system, it has many challenges and obstacles, some of them are technological (magnetic field, CT number, dose calculation, dose rate, etc), financial, throughput, and manpower training. Nevertheless MR-Linac has the potential to improve treatment outcomes, reduce side effects, and enhance patient care in the field of radiation oncology.

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February 26 - Walter Block, PhD | MR Guided Neurosurgery: From Neuromodulation to Gene Therapy

MR Guided Neurosurgery: From Neuromodulation to Gene Therapy


Walter Block, PhD
Professor, Medical Physics and Biomedical Engineering
University of Wisconsin–Madison

MRI has been touted for over 30 years as a transformative powerful means of guiding surgery but the field has grown relatively slowly. The field has made some significant advances over the last 10 years in neurosurgery. The MR scanner geometry aligns well with brain access and MRI has unique abilities to monitor therapy after minimally-invasive devices are introduced into the brain through small holes created in the skull.

This talk will feature contributions accomplished at UW-Madison in the acceleration and simplification of aligning devices for applications in neuromodulation, focal epilepsy treatment, bio-psychiatry, and stem cell therapy. The talk will close by describing an opportunity for UW–Madison to lead a coming push in the treatment of devastating pediatric neurodegenerative diseases through intraparenchymal gene delivery. A collaborative effort in areas of strength such as diffusion imaging and pediatric neurosurgery will be necessary to meet the challenge.

March 4 - Ryan Flynn, PhD | Re-inventing high-dose-rate brachytherapy around the ytterbium-169 isotope

Re-inventing high-dose-rate brachytherapy around the ytterbium-169 isotope

Ryan Flynn, PhD
Medical Physics Division Director
University of Iowa

An approach for improving high-dose-rate brachytherapy treatments is to provide the capability for dynamic partial shielding within applicators. This can reduce the invasiveness of cervical cancer treatments by minimizing needle usage and improve urethral avoidance for prostate cancer patients. Such approaches would require an isotope with a lower average energy than conventional iridium-192. Ytterbium-169 is a promising isotope for this purpose, however, it is more expensive to produce than iridium-192 and has a shorter half-life, providing commercialization challenges. In this presentation an approach to cost-effectively producing and distributing ytterbium-169 will be discussed, along with technologies for physically delivering rotating shield brachytherapy for cervical cancer and prostate patients, and the simulated dosimetric benefits for patients.

March 11 - Matija Milanič, PhD | What light can tell us about blood vessels?

What light can tell us about blood vessels?

Matija Milanič, PhD
associate professor, senior researcher, coordinator of medical physics study program
Faculty of Mathematics and Physics, University of Ljubljana
Jozef Stefan Institute

Knowledge of tissue properties, such as cell arrangement, tissue oxygenation, and blood vessel density and geometry, is crucial for diagnosing and treating diseases like cancer and inflammation. I will briefly overview three optical imaging techniques, namely hyperspectral imaging (HSI), laser speckle contrast imaging (LSI), and optical coherence tomography angiography (OCTA), which are used to image tissue vascularization. These methods can reveal physiological and morphological information about the tissues, such as hemoglobin species, lipid and water distribution, and blood perfusion. We apply these methods to animal and human tumor and inflammation models and show how they can help us understand the role of blood vessels in disease and optimize the treatment.

March 18 - P. Jack Hoopes, DVM, PhD | Translational Flash Radiation: Pre-Clinical Models and Research Results

Translational Flash Radiation: Pre-Clinical Models and Research Results

P. Jack Hoopes, DVM, PhD
Professor of Radiation Oncology and Surgery
Greisel School of Medicine, Dartmouth

FLASH or Ultra High Dose Rate radiation is a new technique that delivers a dose of radiation to a tumor target up to 5000 times faster than occurs in conventional radiation therapy. Until recently, the scarcity of UHDR/FLASH irradiators, meant much of the FLASH research was physics, engineering and modeling based. However, a growing number of in vivo studies have now shown potentially important tissue effect differences following FLASH and conventional radiation, at the same doses and treatment parameters. Important there does not appear a significant difference in tumor control between FLASH and Conventional radiation, at comparable doses. Although the role of oxygen remains at the FLASH RT forefront, mechanistic detail is unclear. Currently most of the in vivo FLASH studies have been conducted in rodents (brain, intestine, lung, and skin), although large animal studies are now merging. Some FLASH-based studies have shown normal tissue damage reduction in the 10-20% range.

Tissue type, alpha/beta ratio, total dose, post -irradiation interval and beam structure remain significant unknown factors in optimization of the FLASH effect damage reduction. However, there are two major issues that provide the greatest challenge to the FLASH effect hypothesis: lack of a logical, scientific and repeatable mechanism, and the lack of detailed rodent and large animal studies that include morphologic damage complexity, variability, and late effect situations. Current Dartmouth studies comparing FLASH and Conventional RT are focused on these parameters and oxygen-based mechanisms in rodent, porcine and clinical canine/feline tumor/normal tissue models. These studies and results will be discussed.

April 1 - Marie Muller, PhD | Quantitative ultrasound in complex tissues: finding new sources of contrast

Quantitative ultrasound in complex tissues: finding new sources of contrast

Marie Muller, PhD
Associate Professor, Mechanical and Aerospace Engineering
NC State University

Highly heterogeneous tissues such as lungs or bone break the fundamental assumptions at the basis of conventional ultrasound imaging. Ultrasound signals that propagate in such media are too complex to form conventional images. However, this complexity is also a very rich source of information, since complex acoustic signatures are packed with information on tissue structure.

Our objective is to extract quantitative information on tissue microstructure, by applying physics-based models of ultrasound scattering.  We demonstrate that such approaches can be applied to the characterization and staging of lung diseases such as pulmonary fibrosis and edema, or of bone diseases such as osteoporosis. These chronic diseases require frequent monitoring. Developing non-invasive, non-ionizing and quantitative methods to evaluate the progression of such diseases is therefore critical.

We also show that novel imaging methods for lung cancer using multiple scattering as a source of contrast holds great promise for the real-time guiding of lung cancer surgery.

April 8 - Jennifer Smilowitz, PhD | Radiation Oncology at the Madison VA

Radiation Oncology at the Madison VA

Jennifer Smilowitz, PhD
Chief Medical Physicist, William S. Middleton Memorial Veterans’ Hospital
Clinical Professor, Departments of Human Oncology and Medical Physics
University of Wisconsin-Madison

The Veterans Health Administration is the largest integrated health care system in the US, serving > 9M Veterans annually. The William S Middleton VA Hospital (“The Madison VA”) is the 41st (and most recently commissioned) radiation oncology department in the system. Like almost half the radiation oncology departments, the medical physicists are contracted through a university affiliate.

I will speak about my experiences as UW Faculty serving as the Chief Medical Physicist at the Madison VA. This has been rewarding experience with many similarities and differences with respect to the last 18 years of practice solely within the UW system. We have been treating Veterans since August 2022 with state-of-the-art external beam radiation oncology modalities such as stereotactic body radiotherapy and breathhold gated treatments. Our linear accelerator is beam matched to those at UW, and we have been able to leverage our affiliation with UWHC (physicists and physicians) to provide highly technical radiation therapy at the Madison VA. We have tremendous support from the local VA and the National Radiation Oncology Program (NROP.) In addition to our strong partnership with UWHC, we align our clinical, safety and research practices with NROP to provide a cohesive radiation oncology service to all Veterans. Being aligned with both the UW and NROP provides many opportunities and challenges. One example is the volume of Veterans treated presents a unique position to engage in clinical trials, both within and external to the VA systems.

April 15 - Denis Bergeron, PhD | Realization and dissemination of activity standards for medically important alpha emitters

Realization and dissemination of activity standards for medically important alpha emitters

Denis Bergeron, PhD
Research Chemist
National Institute of Standards and Technology (NIST)

Targeted alpha therapy (TAT) promises a path to effective treatment of cancers with reduced impact to healthy tissue. There is growing recognition that precise, patient-specific dosimetry will be key to realizing the full potential of TAT. In any radiopharmaceutical therapy, the critical input for absorbed dose estimates is the administered activity. Whether for a therapeutic agent or a complementary molecular imaging agent, we want to administer enough activity to do the job, but no more. The SI derived unit for activity is the becquerel (Bq), and it is the responsibility of metrology institutes like NIST to realize the unit and provide the measurement infrastructure to support its dissemination to end users. This talk will introduce the concepts behind NIST standards for activity and how traceability to those standards is established.

April 22 - Ke Sheng, PhD | Unlimiting Medical Physics Research in Radiation Oncology

Unlimiting Medical Physics Research in Radiation Oncology

Ke Sheng, PhD
Professor and Vice Chair of Medical Physics
University of California, San Francisco

Therapeutic medical physics research has traditionally served the purpose of radiation oncology clinical needs, which have motivated groundbreaking inventions such as IMRT and IGRT. The model, however, has been increasingly challenged when the clinical needs provide insufficient or unclear guidance, leading to stagnant physics research. The presentation will focus on new avenues of physics research based on the broad definition of X-ray physics and physical modeling of the tissues as a means to unlimiting medical physics research. The presentation will demonstrate examples of research not driven by immediate clinical needs but by the theoretical potential of first principles that define physics.

April 29 - Lonie Salkowski, MD, PhD | Trials and tribulations of implementing interpretive skills simulation system for resident breast imaging education

Trials and tribulations of implementing interpretive skills simulation system for resident breast imaging education

Lonie Salkowski, MD, PhD
Professor, Department of Radiology
University of Wisconsin–Madison

Residents have only twelve weeks of breast imaging to become proficient in all modalities and skills. There is no cross training in other rotations nor call experience to support their knowledge development in breast imaging. There is a need for effective methods to enhance trainee interpretive skills in breast imaging. This study explored the feasibility and challenges associated with the implementation of an interpretive skills simulation system for breast imaging into residency education.