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Evaluating Parotid Gland Dose Between Electronic Tissue Compensation and Field in Field Treatment Techniques for Parotid Sparing in Whole-Brain Radiotherapy
Full text linkPurpose:
The parotid glands are essential to salivary function and patient quality of life, yet they are not routinely prioritized as organs at risk (OARs) during whole-brain radiotherapy (WBRT). With growing recognition of long-term side effects like xerostomia in patients with prolonged survival after WBRT, parotid-sparing techniques warrant investigation. This study compares radiation dose to the parotid glands using three different 3D conformal WBRT planning approaches: field-in-field (FiF) with blocking, electronic tissue compensation (eCOMP) without blocking, and eCOMP with blocking.
Methods and Materials:
A retrospective study was conducted on 20 patients previously treated with 3D conformal WBRT. Original eCOMP plans were re-evaluated, and new FiF plans were created using the same field borders, planning parameters, and CT simulation datasets. Parotid glands were delineated post hoc using automated contouring. Dose metrics including mean dose (Dmean), maximum dose (Dmax), and volumetric coverage at 12.30Gy and 20Gy (V12.3, V20) were analyzed for both left and right parotid glands. Statistical comparisons between techniques were conducted using multivariate analysis of variance (MANOVA) with Bonferroni correction.
Results:
Parotid gland dose was significantly reduced in both FiF with blocking and eCOMP with blocking plans compared to the original eCOMP plans without blocking. For the left parotid, FiF with blocking yielded a Dmean of 5.86Gy and eCOMP with blocking 5.58Gy, compared to 16.51Gy for eCOMP without blocking (p \u3c .0001). Right parotid values showed a similar trend, with both blocking techniques achieving significantly lower Dmean and V20 values. FiF with blocking and eCOMP with blocking both met or fell below QUANTEC thresholds for parotid dose, while eCOMP without blocking did not.
Conclusion:
Incorporating blocking into 3D conformal WBRT—whether via FiF or eCOMP—substantially reduces parotid gland dose. These findings support the inclusion of parotid-sparing strategies in standard WBRT planning, particularly for patients with potential for longer survival. As xerostomia is closely linked to quality of life, future prospective studies are needed to evaluate the clinical impact of these dosimetric improvements and to establish formal guidelines for parotid sparing in WBRT
Investigation into Intraocular Pressure Distribution via Computer Aided Engineering (CAE)
Full text linkThe leading cause for irreversible blindness and vision loss is glaucoma - an eye condition associated with elevated intraocular pressure (IOP). Increased IOP is also seen during other pathological conditions like spaceflight-associated neuro-ocular syndrome (SANS), and non-pathological conditions as when playing a wind instrument. The study aimed to describe the influence of different vitreous cavity size as well as vitreous fluid viscosity on the IOP as measured at the back of the eye on the retina. Improved understanding of eye pressure transmission can aid in a better understanding of eye diseases. The experiment conducted included cavities of varying size and filled with different vitreous fluid substitute viscosities. The same cavity sizes and vitreous fluid viscosities were modeled in a simulation conducted in computational fluid dynamics (CFD). The experiment determined the large size vitreous cavity was preferable at low and medium vitreous fluid viscosities. However, at high viscosity, the small cavity resulted in the lowest pressure difference. In contrast, simulation results indicated that the medium sized cavity was preferable at low vitreous fluid viscosity, while the large cavity was preferable at both medium and high vitreous fluid viscosities. Overall, there were marked discrepancies between the simulation and experimental results. Further improvements must be made to the simulation model and experimental setup for better agreement
Students Lack Effective Collaboration Skills
Full text linkIt has been seen through field experience and through research that students lack the ability to effectively learn through collaboration. The research has shown that there tends to be a lack of authentic learning when using collaboration projects/activities because students do not possess the skills that are needed to collaborate effectively. The ability to collaborate needs to be explicitly taught through modeling and scaffolding. This project examines research on the importance of collaborative learning and the required skills that students need to be successful. The project used research to develop a professional development session that allows teachers to see the importance of collaborative learning skills and provides resources that can be used in secondary education to explicitly teach the 21st century skill of collaboration to students. The professional development provides group norms, group roles, group contract, conflict resolution strategies, daily reflection for students, and a collaboration lesson. The session will be considered successful if teachers are able to use the resources in the classroom and provide qualitative data of students developing collaborative learning skills
Cone vs. VMAT SRS planning for dual targets: effects of target size, separation, and isocenter displacement
No full textObjective: This study compares cone-based and volumetric modulated arc therapy (VMAT) stereotactic radiosurgery (SRS) planning for dual intracranial targets, examining the effects of target size, inter-target separation, and isocenter displacement on dosimetric outcomes. Methods: Plans were generated for spherical targets of 8.0 mm, 10.0 mm, and 12.0 mm diameters using both VMAT and cone-based techniques with single-isocenter configurations. Key metrics including maximum dose, volumes of normal brain receiving 12 Gy and 50% of the prescription dose (V12Gy, V50%), high-dose volume (V100%), gradient index, and target coverage were evaluated. Results: Cone-based plans demonstrated superior dose conformity and reduced normal tissue exposure across all target sizes, reflected by lower gradient index and smaller V12Gy and V50% volumes. VMAT plans achieved comparable or slightly improved target coverage but exhibited increased dose spill to surrounding brain tissue. Statistical analysis using Fisher’s Exact Test showed no significant association between planning technique and achieving full target coverage (p = 1.0). Conclusion: These findings suggest that while both techniques are effective for dual-target SRS, cones provide improved dose conformity and normal brain sparing
Optimizing Palliative Spine Radiation: A Dosimetric Comparison of Hybrid Arc Therapy and Conventional APPA Techniques
No full textThis study aimed to evaluate the dosimetric impact of Hybrid Arc Palliative Radiation Therapy (HART) versus conventional anterior-posterior/posterior-anterior (APPA) beam arrangements for thoracic spine metastases. The primary objective was to assess differences in conformity, homogeneity, and organ-at-risk (OAR) sparing between the two techniques. A retrospective plan comparison was conducted using anonymized datasets from twenty patients previously treated with HART. Each case was replanned using a standard APPA technique, normalized to match the target coverage of the original HART plan within 0.1%. All plans were prescribed 20 Gy in 5 fractions. Plan quality was evaluated using conformity index (CI), homogeneity index (HI), and predefined dose-volume metrics. Plans using the HART technique demonstrated significantly improved dose conformity (median CI 1.16 vs. 2.63, P = .0004) and homogeneity (median HI 1.12 vs. 1.25, P \u3c .0001) compared to APPA plans. The APPA technique delivered higher doses to critical structures, including the spinal cord, esophagus, heart, stomach, and small bowel. HART increased low-dose exposure to the liver, kidneys, lungs minus clinical target volume (CTV), and small bowel, although all values remained within clinically acceptable limits. Compared to APPA, HART provided superior target conformality and homogeneity while reducing high-dose exposure to critical thoracic structures. These findings support HART as a promising approach for palliative thoracic spine radiation, with potential to improve patient comfort and reduce treatment-related toxicity
Learning Labs as a Professional Development Model to Strengthen Special Education Literacy Instruction
No full textSpecial education teachers face unique challenges in delivering effective literacy instruction to students with disabilities, yet traditional professional development often remains disconnected from the realities of special education classrooms. These conventional models frequently lack opportunities for sustained collaboration, reflective practice, and the application of evidence-based strategies tailored to diverse learner needs. This project presents a comprehensive plan for designing and facilitating Learning Labs, a form of embedded professional development grounded in constructivist and sociocultural theories. The Learning Lab model emphasizes collaborative inquiry, pedagogically productive talk, and the analysis of authentic instructional artifacts to deepen teachers’ understanding of effective literacy instruction. Building on existing research that supports job-embedded, teacher-driven professional learning, this project offers a framework specifically adapted for special education contexts, addressing a significant gap in the professional development literature. This model incorporates research-informed instructional strategies aligned with High-Leverage Practices for Special Education and Michigan’s Literacy Essentials for Grades 4 and 5, providing structured and actionable opportunities for teachers to enhance their practice. The design emphasizes sustainability, contextual relevance, and professional ownership, with the goal of increasing teacher confidence and instructional capacity in delivering explicit, differentiated, and individualized instruction to students with disabilities. By offering a replicable and meaningful alternative to traditional workshop-based professional development, this project contributes to the field of special education by proposing a practical and theory-driven approach to improving teacher learning and ultimately advancing literacy outcomes for students in resource room settings
Diagnostic Imaging-based Radiation Therapy Planning (DBRP) for Non-Small Cell Lung Cancer (NSCLC) Patients
No full textPurpose
Non-small cell lung cancer (NSCLC) patients benefit by starting radiation therapy (RT) promptly upon diagnosis. Diagnostic scan-based radiation therapy planning (DBRP) eliminates the need for computed tomography (CT) simulation. This is a retrospective study comparing dosimetric differences between volumetric arc therapy (VMAT) diagnostic scan-based plans recalculated onto simulation CT scans.
Methods
Radiotherapy (60 or 66 Gy in 20-30 fractions) for eight NSCLC patients was planned on diagnostic CTs. The plans were recalculated onto the fused simulation CTs, mimicking first treatment setups. Dose-volume histogram (DVH) were used to compare the minimum dose received by 95% of the planning target volume and 98% of the gross tumor volume (PTV D95%, D98%, and GTV D98%), the minimum dose received by 2% of the PTV (PTV D2%), plan homogeneity (defined as D2% divided by the prescription dose), and doses to organs at risk (lungs, heart, esophagus, spinal cord, left anterior descending artery (LAD), bronchial tree, and brachial plexus).
Results
Significant differences were observed between the differences in medians of PTV D95% [-4.8%, sign test, p-value=0.01, E.S.=1.15], PTV D98% [-8.6%, sign test, p-value=0.01, E.S.=1.13], and nodal GTVn D98% [-6.7%, sign test, p-value=0.01, E.S.=1.07]. Significant differences were observed in the median PTV D2% [+2.7%, sign test, p-value=0.01, E.S.=1.14] of the PTV volumes (PTV D2%) and the median homogeneity indexes [+3.7%, sign test, p-value=0.01, E.S.=1.03]. No significant differences were observed in the primary GTVp D98% or in the doses to organs at risk (OAR).
Conclusion
The median plan differences observed are similar to parametric results observed in dosimetry comparison studies of palliative-intent DBRP. A successful DBRP process for NSCLC patients was retrospectively demonstrated, suggesting that the technique may be feasible for some definitive RT courses. The study’s limitations were a small number of patients and a simplified target delineation process. Further research is needed to determine processes specific to NSCLC for DBRP. Special quality assurance measures and processes would also be needed
Comparison of Psychological Data between Populations, A Measurement Perspective
No full textIn cross-cultural psychology there is a strong tradition of psychometric analysis of bias and invariance (equivalence) after collection of data in distinct populations with identical instruments developed in one population. This implies a focus on measurement outcomes and an operationalist orientation to science. Here we explore how a focus on joint development and content validity of instruments combined with relaxation of the demand of item identity can provide an additional perspective. Three points are addressed:(1) Any comparison between participants from two, or more, populations presumes a common quality (property, attribute) and requires a common measurement scale, a “standard of comparison”.(2) Stevens (1946) four levels of measurement are distinguished for a standard of comparison; this level (nominal, ordinal, interval, ratio) determines to which kinds of psychometric comparisons data are open.(3) A standard of comparison can be based on an existing instrument that is transferred from one population to some other population, with or without modification. It can also be a newly developed instrument that may be based, but (we argue) need not be based, on a set of stimuli or items that is identical across populations.Three considerations are mentioned: (i) representation of all participating populations at all stages of instrument development, (ii) emphasis on content validity, and (iii) various tools such as item banks and item parameters from IRT models that can help to derive a comparison standard from only partly overlapping item sets
Empowering General Educators: Supporting Students with Learning Disabilities Through Inclusive Tier Two Practices
No full textMany general education teachers enter the profession with minimal training in how to effectively support students with learning disabilities, particularly those who require Tier Two interventions but do not qualify for special education services. This lack of preparation contributes to reduced instructional confidence, inconsistent intervention practices, and missed opportunities to support struggling learners. Grounded in Vygotsky’s Zone of Proximal Development, Universal Design for Learning (UDL), and Bandura’s theory of self-efficacy, this capstone project addresses the urgent need for ongoing, practical professional development tailored to the realities of inclusive classrooms. The literature highlights the importance of sustained, collaborative, and contextually embedded learning experiences to improve teacher capacity and intervention fidelity.
In response, this project proposes a structured school based professional development program designed to equip general educators with evidence-based strategies, tools, and confidence to deliver effective Tier Two interventions. The program includes recurring learning sessions, implementation planning tools, collaborative reflection opportunities, and ongoing coaching from instructional support staff. Evaluation methods include pre and post training surveys, teacher reflections, student performance data, and qualitative feedback from participants. The goal is to embed inclusive instructional practices into daily teaching, foster collaboration between educators, and create a culture of continuous professional growth that supports all learners, especially those at risk of falling through the cracks