Engaging grade school learners with an interactive medical imaging activity.

This case report describes a 45-min active learning lesson plan that engages 4th-5th and 6th-8th grade school students in spatial reasoning through a review of medical imaging. The lesson plan reviews different planar orientations and cross-sections of computed tomography (CT) images of familiar objects. The lesson is designed to introduce students to the idea that scientists are key contributors to healthcare, including in medical imaging technologies that facilitate the visualization of internal structures of patients without invasive procedures.

AAPM Medical physics practice guideline 15.A: Peer review in clinical physics.

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States.

Dosimetric characterization of foam padding with posterior fields in palliative radiation therapy.

Patients undergoing external beam radiation therapy for the palliative treatment of painful bony metastases may have difficulty maintaining a still position on a rigid uncovered couch top, both during CT simulation as well as during patient setup, image guidance, and treatment on the linear accelerator. For these patients, a thin foam pad or mattress is sometimes used to mitigate patient discomfort. It was desired to quantify the effect of the padding in cases in which the patient is to be treated supine with posterior beams when the majority of the beam weighting traverses both the couch and the pad.

Overview of medical physics education and research programs in a non-academic environment.

Northwest Medical Physics Center (NMPC) is a nonprofit organization that provides clinical physics support to over 35 radiation therapy facilities concentrated in the Pacific Northwest. Although clinical service is the primary function of NMPC, the diverse array of clinical sites and physics expertise has allowed for the establishment of structured education and research programs, which are complementary to the organization's clinical mission. Three clinical training programs have been developed at NMPC: a therapy medical physics residency program accredited by the Commission on Accreditation of Medical Physics Education Programs (CAMPEP), an Applied Physics Technologist (APT) program, and a summer undergraduate internship program.

Equity, diversity, and inclusion topics at a medical physics residency journal club.

A journal club program was initiated in a clinically focused, geographically distributed medical physics therapy residency program. This program currently supports two residents at different clinical sites, who regularly present at the new journal club. For one of the sessions, residents were assigned to present on topics related to the broad themes of equity, diversity, and inclusion (EDI) in the context of medical physics, radiation oncology, or medical oncology.

Therapeutic radiation beam output and energy variation across clinics, technologies, and time.

Over the past several decades, a medical physics service group covering 35 clinical sites has provided routine monthly output and energy quality assurance for over 75 linear accelerators. Based on the geographical spread of these clinics and the large number of physicists involved in data acquisition, a systematic calibration procedure was established to ensure uniformity. A consistent measurement geometry and data collection technique is used across all machines for every calendar month, using a standardized set of acrylic slabs.

AAPM medical physics practice guideline 13.a: HDR brachytherapy, part A.

The American Association of Physicists in Medicine (AAPM) is a nonprofit professional society whose primary purposes are to advance the science, education, and professional practice of medical physics. The AAPM has more than 8000 members and is the principal organization of medical physicists in the United States. The AAPM will periodically define new practice guidelines for medical physics practice to help advance the science of medical physics and to improve the quality of service to patients throughout the United States.

The potential of biology-guided radiation therapy in thoracic cancer: A preliminary treatment planning study.

Purpose: We investigated the feasibility of biology-guided radiotherapy (BgRT), a technique that utilizes real-time positron emission imaging to minimize tumor motion uncertainties, to spare nearby organs at risk.

Methods: Volumetric modulated arc therapy (VMAT), intensity-modulated proton (IMPT) therapy, and BgRT plans were created for a paratracheal node recurrence (case 1; 60 Gy in 10 fractions) and a primary peripheral left upper lobe adenocarcinoma (case 2; 50 Gy in four fractions).

Results: For case 1, BgRT produced lower bronchus V40 values compared to VMAT and IMPT.

Commissioning a multileaf collimator virtual cone for the stereotactic radiosurgery of trigeminal neuralgia.

A multileaf collimator (MLC), virtual-cone treatment technique has been commissioned for trigeminal neuralgia (TGN) at Tri-Cities Cancer Center (TCCC). This novel technique was initially developed at the University of Alabama in Birmingham (UAB); it is designed to produce a spherical dose profile similar to a fixed, 5-mm conical collimator distribution. Treatment is delivered with a 10-MV flattening-filter-free (FFF) beam using a high-definition MLC on a Varian Edge linear accelerator.

Identification of miRNA Associated with Reduced Survival after Whole-Thorax Lung Irradiation in Non-Human Primates.

Thoracic exposure to ionizing radiation can lead to delayed injuries to the heart and lung that are serious and even life-threatening. These injuries are difficult to predict since they manifest over many weeks and months. To identify noninvasive, tissue-specific biomarkers for the early detection of late radiation injury, circulating microRNA (miRNA) levels were measured in non-human primates (NHP, Macaca mulatta) that received a single exposure of whole-thorax lung irradiation (WTLI) at a dose likely to result in 20% or 75% mortality within 180 days (9.

Simple phantom fabrication for MRI-based HDR brachytherapy applicator commissioning.

A new high dose rate (HDR) brachytherapy program was initiated in a community hospital setting, with the goal of using magnetic resonance (MR) images with the implant in place during the planning process. Physics acceptance testing and commissioning was completed for key program components, including multiple applicators. To image new applicators for MRI-based planning prior to use with patients, agar gel doped with copper sulfate was created using simple, MR-safe household materials as a practical and inexpensive alternative to custom-machined precision phantoms.

A gottingen minipig model of radiation-induced coagulopathy.

Purpose: Total body irradiation of the Gottingen minipig results in a characteristic hematopoietic response, including anemia, neutropenia, lymphocytopenia, and thrombocytopenia. Currently, there are no well-characterized large or small animal models for radiation-induced thrombocytopenia. The study described here using the Gottingen minipig was focused on understanding which aspects of the coagulation cascade leads to radiation-induced coagulopathy.

The impact of supportive care on survival in large animal models of total body irradiation.

Purpose: Well-characterized animal models that mimic the human response to potentially lethal doses of radiation are necessary in order to assess the efficacy of candidate medical countermeasures under the criteria of the U.S. Food and Drug Administration 'Animal Rule'.

Introducing Health and Medical Physics to Young Learners in Preschool to Fifth Grade.

A hands-on learning activity was developed to introduce young learners to concepts and careers in health and medical physics. Inexpensive materials were used to create a work station with learning tools that were designed to be approachable and accessible for this audience. Visitors to a local independent, nonprofit science museum may interact with the activity work station to learn basic information regarding radiation in everyday life and to hear about careers in radiation sciences.

Dosimetric characterization of a rigid, surface-contour-specific thermoplastic bolus material.

A dosimetric analysis of a commercially available thermoplastic sheet bolus, Klarity EZ Bolus, was completed. Attenuation characteristics were evaluated using different configurations of a rectilinear water-mimicking plastic phantom irradiated by a high-energy linear accelerator using three photon energies, five electron energies. These results were compared with data obtained during the linear accelerator commissioning process to determine depths of water that attenuated beams similarly.

A Comparative Dose-response Relationship Between Sexes for Mortality and Morbidity of Radiation-induced Lung Injury in the Rhesus Macaque.

Radiation-induced lung injury is a characteristic, dose- and time-dependent sequela of potentially lethal, delayed effects of acute radiation exposure. Understanding of these delayed effects to include development of medical countermeasures requires well-characterized and validated animal models that mimic the human response to acute radiation and adhere to the criteria of the US Food and Drug Administration Animal Rule. The objective herein was to establish a nonhuman primate model of whole-thorax lung irradiation in female rhesus macaques.

Redefining and reinvigorating the role of physics in clinical medicine: A Report from the AAPM Medical Physics 3.0 Ad Hoc Committee.

Derived from 2 yr of deliberations and community engagement, Medical Physics 3.0 (MP3.0) is an effort commissioned by the American Association of Physicists in Medicine (AAPM) to devise a framework of strategies by which medical physicists can maintain and improve their integral roles in, and contributions to, health care and its innovation under conditions of rapid change and uncertainty.

American Association of Physicists in Medicine Task Group 263: Standardizing Nomenclatures in Radiation Oncology.

A substantial barrier to the single- and multi-institutional aggregation of data to supporting clinical trials, practice quality improvement efforts, and development of big data analytics resource systems is the lack of standardized nomenclatures for expressing dosimetric data. To address this issue, the American Association of Physicists in Medicine (AAPM) Task Group 263 was charged with providing nomenclature guidelines and values in radiation oncology for use in clinical trials, data-pooling initiatives, population-based studies, and routine clinical care by standardizing: (1) structure names across image processing and treatment planning system platforms; (2) nomenclature for dosimetric data (eg, dose-volume histogram [DVH]-based metrics); (3) templates for clinical trial groups and users of an initial subset of software platforms to facilitate adoption of the standards; (4) formalism for nomenclature schema, which can accommodate the addition of other structures defined in the future. A multisociety, multidisciplinary, multinational group of 57 members representing stake holders ranging from large academic centers to community clinics and vendors was assembled, including physicists, physicians, dosimetrists, and vendors.

Experimental investigation of GafChromic EBT3 intrinsic energy dependence with kilovoltage x rays, Cs, and Co.

Purpose: To determine experimentally the intrinsic energy response, k , of EBT3 GafChromic radiochromic film with kilovoltage x rays, Cs, and Co in therapeutic and diagnostic dose ranges through direct measurement with an accompanying mathematical approach to describe the physical processes involved.

Methods: The EBT3 film was irradiated with known doses using Co, Cs, and 13 NIST-matched kilovoltage x-ray beams. Seven dose levels, ranging from 57 to 7002 mGy, were chosen for this work.

Deep inspiration breath hold with electromagnetic confirmation of chest wall position for adjuvant therapy of left-sided breast cancer: Technique and accuracy.

Purpose: With most patients now living long after their breast cancer diagnosis, minimizing long-term side effects of breast cancer treatment, such as reducing late cardiac and pulmonary side effects of radiation therapy (RT), is particularly important. It is now possible to use an electromagnetic tracking system to allow real-time tracking of chest wall (CW) position during the delivery of RT. Here, we report our experience using electromagnetic surface transponders as an added measure of CW position during deep inspiration breath hold (DIBH).

VMAT testing for an Elekta accelerator.

Volumetric-modulated arc therapy (VMAT) has been shown to be able to deliver plans equivalent to intensity-modulated radiation therapy (IMRT) in a fraction of the treatment time. This improvement is important for patient immobilization/localization compliance due to comfort and treatment duration, as well as patient throughput. Previous authors have suggested commissioning methods for this modality.

An isocentrically mounted stand for total body irradiation.

The purpose of this study was to construct a stand to support a patient for total body photon irradiation and to expedite the set-up and treatment by rotating the stand. As in other isocentric treatments, the midline dose is impacted less by source-to-skin distance variations. The method of immobilizing the patient is described.