About

Dennis L. Parker, PhD, is a founding member of the Utah Center for Advanced Imaging Research. Over his nearly 40 years at the University of Utah, he has mentored more than 80 trainees, many of whom have gone on to become faculty members themselves. Dr. Parker is recognized as an expert in MRI physics, contributing significantly to the field through his extensive experience and leadership within the Neurovascular Imaging Program at the University of Utah School of Medicine.

Research topics

• Medicine
• Radiology
• Physics
• Nuclear medicine
• Biomedical engineering
• Optics
• Computer Science
• Materials science
• Cardiology
• Chemistry
• Engineering
• Nuclear magnetic resonance
• Engineering management
• Pathology
• Internal medicine
• Acoustics
• Medical physics
• Surgery

Selected publications

• Impact of breast biopsy markers on magnetic resonance-guided focused ultrasound

  International Journal of Hyperthermia · 2026-02-23

  articleOpen access

  BACKGROUND: The placement of a biopsy marker at the time of breast biopsy is standard of care to mark the biopsy site and facilitate surgical excision. However, their impact on incisionless treatments like magnetic resonance-guided focused ultrasound remains underexplored. These factors are important considerations for the design and execution of translational research in this field. METHODS: tissue with and without markers present was estimated using measurements from thermal dose and gross tissue processing. RESULTS: Substantial variability in artifact size and shape was observed across the markers. Thermometry showed both imaging and measurement artifacts, with off-target sites showing erroneous temperature change measurements of -30 to 100 °C in some cases. Acoustic field measurements revealed shape- and material-dependent distortions when markers were positioned near the ultrasound focus. Ablation experiments showed mixed effects on treatment volumes. CONCLUSION: The presence of biopsy markers introduces marker-dependent complexities into magnetic resonance-guided focused ultrasound treatment planning and monitoring. Reliable monitoring and energy delivery are achievable when the target is sufficiently far from the marker but become unreliable when the target is close to the marker. Accordingly, the potential impacts of biopsy markers on the safety and efficacy of MR-guided focused ultrasound treatments should be considered carefully.

  PublisherDOI

• Impact of breast biopsy markers on magnetic resonance-guided focused ultrasound

  Figshare · 2026-01-01

  articleOpen access

  The placement of a biopsy marker at the time of breast biopsy is standard of care to mark the biopsy site and facilitate surgical excision. However, their impact on incisionless treatments like magnetic resonance-guided focused ultrasound remains underexplored. These factors are important considerations for the design and execution of translational research in this field. Five commercially available markers were evaluated. Magnetic resonance imaging studies characterized artifact size across various treatment planning and monitoring sequences, as well as MR thermometry performance during focused ultrasound heating. Hydrophone scans collected acoustic field measurements in the presence of biopsy markers. Ablated volume in <i>ex vivo</i> tissue with and without markers present was estimated using measurements from thermal dose and gross tissue processing. Substantial variability in artifact size and shape was observed across the markers. Thermometry showed both imaging and measurement artifacts, with off-target sites showing erroneous temperature change measurements of −30 to 100 °C in some cases. Acoustic field measurements revealed shape- and material-dependent distortions when markers were positioned near the ultrasound focus. Ablation experiments showed mixed effects on treatment volumes. The presence of biopsy markers introduces marker-dependent complexities into magnetic resonance-guided focused ultrasound treatment planning and monitoring. Reliable monitoring and energy delivery are achievable when the target is sufficiently far from the marker but become unreliable when the target is close to the marker. Accordingly, the potential impacts of biopsy markers on the safety and efficacy of MR-guided focused ultrasound treatments should be considered carefully.

  PublisherDOI

• Effect of spatial resolution and heating duration on accuracy of dynamic proton resonance frequency shift temperature measurement with k-space weighted image contrast reconstruction during focused ultrasound

  Magnetic Resonance Imaging · 2026-04-10

  articleOpen access

  Purpose: Single-reference variable flip angle Stack-of-Stars (SR-VFA-SoS) thermometry with KWIC reconstruction provides simultaneous aqueous and fatty tissue temperature monitoring. This work evaluates the effect of k-space weighted image contrast (KWIC) reconstruction of a SR-VFA-SoS sequence on the accuracy of both proton resonance frequency shift (PRFS) and T 1 -based thermometry with different temporal footprints, spatial resolutions, echo times, and heating durations. Methods: Magnetic resonance-guided focused ultrasound (MRgFUS) sonications were performed using an asymmetric KWIC-reconstructed single-reference variable flip angle Stack-of-Stars (SR-VFA-SoS) sequence and a validated segmented echo planar imaging (segEPI) thermometry sequence in tissue-mimicking phantoms and an in vivo rabbit model. KWIC windows of projection length 89–377, voxel resolutions of 1.2 mm isotropic and 1.5 × 1.5 × 2.0 mm, three different sets of echo times, and heating durations of 30.2–123.3 s were evaluated. Peak temperature accuracy, calculated cumulative thermal dose (CTD), and temporal lag were assessed. Results: In phantoms and the animal model, significant differences in peak temperatures were observed between the SR-VFA-SoS and segEPI thermometry at 1.5 × 1.5 × 2.0 mm voxel size, but not 1.2-mm isotropic. Temperature discrepancies were independent of echo time. Prolonged heating duration with lower power at the larger voxel size resulted in lower peak temperature error. Asymmetric KWIC-reconstructed SR-VFA-SoS peak temperatures were consistently temporally shifted later than segEPI peak temperatures. Conclusion: SR-VFA-SoS thermometry with KWIC reconstruction offers promising temporal resolution for simultaneous aqueous and fatty tissue temperature monitoring during MRgFUS. However, temporal blurring due to KWIC reconstruction results in underestimation and temporal shifting of peak temperatures for large voxel sizes and short heating durations. These observations highlight the need for careful KWIC and MRgFUS parameter optimization.

  PublisherDOI

• Impact of breast biopsy markers on magnetic resonance-guided focused ultrasound

  Open MIND · 2026-01-01

  article

  The placement of a biopsy marker at the time of breast biopsy is standard of care to mark the biopsy site and facilitate surgical excision. However, their impact on incisionless treatments like magnetic resonance-guided focused ultrasound remains underexplored. These factors are important considerations for the design and execution of translational research in this field. Five commercially available markers were evaluated. Magnetic resonance imaging studies characterized artifact size across various treatment planning and monitoring sequences, as well as MR thermometry performance during focused ultrasound heating. Hydrophone scans collected acoustic field measurements in the presence of biopsy markers. Ablated volume in <i>ex vivo</i> tissue with and without markers present was estimated using measurements from thermal dose and gross tissue processing. Substantial variability in artifact size and shape was observed across the markers. Thermometry showed both imaging and measurement artifacts, with off-target sites showing erroneous temperature change measurements of −30 to 100 °C in some cases. Acoustic field measurements revealed shape- and material-dependent distortions when markers were positioned near the ultrasound focus. Ablation experiments showed mixed effects on treatment volumes. The presence of biopsy markers introduces marker-dependent complexities into magnetic resonance-guided focused ultrasound treatment planning and monitoring. Reliable monitoring and energy delivery are achievable when the target is sufficiently far from the marker but become unreliable when the target is close to the marker. Accordingly, the potential impacts of biopsy markers on the safety and efficacy of MR-guided focused ultrasound treatments should be considered carefully.

  DOI

• Behavioral Foundations for CBPE: Using the BCW to Advance Individual Readiness to Change

  American Journal of Pharmaceutical Education · 2025-07-17 · 2 citations

  articleOpen access

  The American Association of Colleges of Pharmacy Academic Affairs Committee (2024-2025) was charged with supporting the implementation of competency-based pharmacy education (CBPE) by developing a validated readiness-to-change instrument and offering recommendations to guide adoption. Recognizing that change requires both organizational support and individual engagement, the committee applied established behavior change frameworks, including the Capability, Opportunity, Motivation-Behavior model and the behavior change wheel, to define the actions needed from faculty, administrators, preceptors, and learners. These behaviors align with the 5 core components of CBPE: (1) outcome competencies that are clearly articulated, measurable, and transparent; (2) progressive sequencing of competencies across the curriculum with defined developmental markers; (3) authentic learning experiences embedded throughout the curriculum; (4) learner-centric, competency-focused instruction with individualized learning plans; and (5) longitudinal assessment practices that document competency acquisition and progression. A national Delphi panel and stakeholder focus groups informed the development of the instrument. Additional data gathered at the 2025 American Association of Colleges of Pharmacy Interim Meeting showed general support for CBPE but also identified challenges such as limited faculty familiarity, insufficient resources, gaps in technological infrastructure, and uncertainty around assessment methods. Based on these findings, the committee presents practical recommendations, including faculty development, systems alignment, and leadership support. The report emphasizes that meaningful progress requires coordinated efforts across institutions and roles-built through collaboration, sustained by inclusive leadership, and shaped by the voices of those responsible for teaching and learning. With the right educational infrastructure and stakeholder engagement, CBPE can be effectively implemented to better meet the needs of learners, the profession, and society.

  PublisherDOI

• Flexible, high spatial and temporal resolution absolute thermometry of <scp>MRI</scp> phantoms using ethylene glycol

  Magnetic Resonance in Medicine · 2025-03-30

  articleOpen access

  PURPOSE: Quantitative MRI (qMRI) parameters such as relaxation rates and diffusion parameters are typically temperature dependent. Therefore, using phantoms to evaluate the accuracy of qMRI pulse sequences requires accurate knowledge of the absolute temperature throughout the phantom. This work aims to evaluate the use of ethylene glycol (EG) together with a multi-echo gradient recalled echo (ME-GRE) pulse sequence for MR spectroscopic-based measurement of absolute temperature in phantoms. METHODS: We develop and test a simple MR spectroscopic imaging approach to rapidly, automatically, accurately, and precisely measure absolute temperature at multiple locations throughout a qMRI phantom. A series of EG cubes are located throughout the phantom and imaged with a ME-GRE pulse sequence over a wide range of temperatures (˜7°C-37°C) and on multiple scanners. The resulting images were automatically processed to isolate the EG. The measured spectral peak spacing was calibrated to temperature using fiber optic probes. The accuracy and precision of the measurements were evaluated between scanners over a range of temperatures. RESULTS: The spectral peak spacing of EG can be used to predict temperature with an error of 0.6°C ± 0.3°C with an increase of 0.1°C when evaluated on different scanners. An automatic reconstruction approach without manual input is described, highlighting the feasibility of online implementation on a clinical MRI scanner. CONCLUSION: The described MR spectroscopic imaging approach is easy to implement and provides robust, automatic, and accurate measurement of absolute temperature throughout a phantom.

  PublisherOA PDFDOI

• The effect of concomitant gradient fields on MRI with long readout radial‐based trajectories

  Magnetic Resonance in Medicine · 2025-04-03 · 1 citations

  articleOpen accessSenior author

  Abstract Purpose To demonstrate in theory and practice that concomitant gradient fields (CCGF) can produce substantial imaging artifacts in scans utilizing radial‐based trajectories and to provide strategies to mitigate these effects. Theory and Methods A framework was developed to relate concomitant gradient phase to local point‐spread‐function distortion, which was used to evaluate the effects of trajectory choice and imaging parameters on imaging artifacts. Gradient waveforms for realistic imaging scenarios were simulated and used to determine the effect of CCGF. Phantom and in vivo experiments were performed at 3 T to validate theoretical predictions. Results CCGF‐induced artifacts are shown to be produced in part by increased variation in concomitant gradient phase across view angles. This is shown to increase with increasing gradient strength and contrast index in radial‐based trajectories. Phase variation across view angles and the associated artifacts are shown to be effectively diminished via azimuthal rotation down the echo train in the helical EPI and helical stack‐of‐stars trajectories introduced in this work. Conclusions Concomitant gradient fields are found to produce non‐negligible imaging artifacts in long readout radial‐based trajectories due to variations in the associated phase accrual across view angles. Azimuthal rotation of the readout direction down the echo train, as implemented in the helical EPI and helical stack‐of‐stars trajectories, is shown in simulations, phantoms, and in vivo to mitigate these effects. Substantial improvement is seen in cases of nonaxial imaging with multiple contrasts, quickly varying B 0 inhomogeneity, and/or high gradient amplitudes.

  PublisherOA PDFDOI

• Assessing the Current State of Pharmacy Education: A Strengths-Weaknesses-Opportunities-Threats Analysis

  American Journal of Pharmaceutical Education · 2025-11-19 · 1 citations

  articleOpen access

  OBJECTIVES: This narrative review applies a Strengths, Weaknesses, Opportunities, Threats (SWOT) analysis to evaluate the current state of US pharmacy education, identifying critical areas for urgent reform to meet the demands of a rapidly evolving health care landscape. FINDINGS: A narrative review methodology was used to construct a comprehensive SWOT analysis of pharmacy education. Pharmacy education demonstrates notable strengths, including program diversity, strong accreditation standards, and expanding experiential learning opportunities. However, weaknesses in pharmacy education, such as inconsistent competency standards, fragmented professional identity, curricular overload, and slow responsiveness to technological advances, threaten the profession's future. Opportunities exist to implement competency-based education, leverage digital innovation, strengthen interprofessional training, and reform professional identity development strategies. Yet external threats (including declining enrollments, perceived job market saturation, health care system disruption, and scope-of-practice variability) underscore the urgent need for coordinated action. SUMMARY: Pharmacy education stands at a tipping point. To secure its future relevance, this work suggests that the Academy embrace a national, competency-driven, lifelong learning model and intentionally reform professional identity development. Institutions must assess readiness for change, foster innovation, and rigorously evaluate new educational models. This SWOT analysis provides a roadmap for transformation, urging academic pharmacy to move beyond resistance and lead boldly into a health care future shaped by societal needs, digital health, and interprofessional collaboration.

  PublisherDOI

• From Strength to Struggle: Stakeholder Insights into the Readiness of Tomorrow’s Pharmacists

  American Journal of Pharmaceutical Education · 2025-11-20 · 1 citations

  articleOpen access

  OBJECTIVE: The objectives of this study were to: (1) identify convergent and divergent themes across stakeholder groups regarding the perceived strengths and weaknesses of student pharmacists; and (2) evaluate the alignment of these perceptions with established national and international competency frameworks. METHODS: This study used a qualitative, multistakeholder research design informed by grounded theory and pragmatic epistemological foundations to identify convergent strengths and weaknesses along with gaps. Heatmap and sentiment analyses were also used to demonstrate the strengths of stakeholders' perceptions of the strengths and weaknesses. Lastly, strengths and weaknesses were compared to national and international competency frameworks. RESULTS: Drawing from 27 focus groups with 139 participants across multiple stakeholder categories, the study identified convergent student pharmacist strengths (eg, clinical knowledge, patient-centered care, collaboration) and weaknesses (eg, critical thinking, systems awareness, professional assertiveness). A thematic analysis revealed strong alignment with foundational competencies but significant gaps in leadership, public health engagement, and real-world application of knowledge. Heatmap and sentiment analyses underscored the intensity of stakeholder concerns, particularly regarding students' adaptability in complex clinical settings. A comparative gap analysis with national and international competency frameworks highlighted discrepancies between curricular intentions and experiential realities. CONCLUSION: These findings signal a pressing need for curricular redesign that strengthens systems thinking, decision-making under uncertainty, and professional identity formation. The study offers actionable insights to align pharmacy education with the expectations of contemporary and future health care practice.

  PublisherDOI

• The Hidden Architecture of Inertia: Stakeholder Perspectives on the Most Pressing Challenges in Pharmacy Education

  American Journal of Pharmaceutical Education · 2025-11-21

  articleOpen access

  OBJECTIVE: The objectives of this study were to (1) identify convergent/divergent challenges in pharmacy education, (2) develop a model to demonstrate how these challenges lead to stagnation in pharmacy education, (3) identify systemic drivers/restraining forces that influence change, and (4) explore perceived advantages/disadvantages of educational transformation. METHODS: This qualitative study used grounded theory and thematic analysis to analyze data from 27 focus groups comprising 8 stakeholder groups: students, faculty, preceptors, deans, health care professionals, payors, professional organization leaders, and practice transformation leaders. Discussions were transcribed, coded, and analyzed iteratively to identify themes, stakeholder convergence/divergence, and perceived trade-offs related to educational reform. RESULTS: Four interconnected themes were identified: a persistent competency-practice gap; a fragmented professional identity; rising resource and sustainability challenges; and strong resistance to change. These themes were mapped into 2 reinforcing cycles, the Educational Inertia Cycle and the Professional Identity Cycle, showing how outdated curricula, unclear role definitions, and institutional obstacles continue to create misalignment. Cross-stakeholder analysis revealed shared concerns but varied priorities, with students and preceptors emphasizing practice readiness, while faculty and deans highlighted burnout and resource constraints. A qualitative force field analysis identified key driving and restraining forces, while an advantage-disadvantage matrix outlined perceived trade-offs of proposed reforms, including competency-based education, experiential expansion, and curricular redesign. CONCLUSION: Despite widespread recognition of necessary reforms, pharmacy education faces systemic inertia. Stakeholder insights affirm the urgent need for coordinated, strategic efforts to realign curricula, support faculty, foster identity formation, and modernize assessment. These findings offer a grounded framework for transforming pharmacy education to be more responsive today and ready for tomorrow.

  PublisherDOI

Recent grants

• NIH Grant R01HL048223

  NIH · $3.7M · 2010

• NIH Grant R01EB013433

  NIH · $1.8M · 2016

• NIH Grant R21EB004803

  NIH · $187k · 2005

• NIH Grant R01HL057990

  NIH · $3.2M · 2011

• NIH Grant R01HL053596

  NIH · $1.7M · 2004

Frequent coauthors

• Allison Payne

  University of Utah

  139 shared

• Gerald S. Treiman

  119 shared

• J. Scott McNally

  University of Utah

  90 shared

• Henrik Odéen

  83 shared

• J. Rock Hadley

  University of Utah

  81 shared

• Eugene Kholmovski

  79 shared

• Seong‐Eun Kim

  Korean Association Of Science and Technology Studies

  69 shared

• Nathan McDannold

  Brigham and Women's Hospital

  68 shared

Labs

• Neurovascular Imaging ProgramPI

  Not provided in the HTML snippet.

Awards & honors

• Distinguished Research Award from University of Utah (2000)
• President of the Magnetic Resonance Angiography Club (1998)
• Fellow of the American Institute of Medical and Biomedical E…
• Fellow of the International Society for Magnetic Resonance i…