Citations

Abstract Additive manufacturing (AM), commonly referred to as 3D printing, has been broadly used in the field of medical imaging and radiotherapy. In medical imaging applications, patient‐specific anatomic models have been used to aid in preoperative planning, patient communication, imaging technique assessment and optimization, and medical education. Within the field of radiation therapy, 3D printing finds significance in fabricating patient‐specific immobilization devices, custom bolus devices, anthropomorphic phantoms, brachytherapy devices, and electron therapy devices. Consistent with standard medical physics practices there is a need to establish quality assurance and quality control (QA/QC) protocols, tolerances, and testing frequencies. The diversity of 3D printing technologies and products poses challenges for medical adoption and thus requires guidelines in workflow standardization and establishment of testing procedures. This report is centered around providing comprehensive vendor‐neutral implementation guidelines and recommendations for QC and QA processes. The scope of this report encompasses diverse requirements within medical imaging and radiation therapy settings, serving both clinical and research purposes. Brief overview of 3D printing technology, common materials, and potential clinical applications is provided. QA team, infrastructure, measurement techniques and challenges are discussed. QA processes for each step in 3D printing are discussed in great detail and baseline and action limits are recommended. This report also touched on regulatory considerations. Key recommendations are summarized at the end of the report.

Abstract Cerebral blood flow is stabilized through dynamic adjustments across both macro‐ and microvascular compartments. While dynamic cerebral autoregulation (dCA) quantifies upstream pressure–flow coupling, downstream microvascular responses are less well characterized and may represent a distinct but functionally linked process. This study tested whether a two‐component cascade model, treating dCA and an empirically derived index of microvascular function (MF) as sequential stages can represent the integrated regulation of cortical oxygenation. Data from 41 healthy adults (20–45 years) were analysed. Beat‐to‐beat mean arterial pressure (MAP), middle cerebral artery flow velocity (CBFV) and cortical oxyhaemoglobin (O 2 Hb) were recorded during supine spontaneous oscillations and forced oscillations at 0.05 Hz using repeated sit–stand manoeuvres. Transfer function analysis quantified frequency‐domain gain, phase and coherence for MAP→CBFV (dCA), CBFV→O 2 Hb (MF) and MAP→O 2 Hb (total pathway). The cascade model was computed as the product of dCA and MF transfer functions. The cascade model derived indices showed strong correlations with total pathway gain, phase and coherence measures during both spontaneous and forced oscillations, with improved linear coupling under forced oscillations. These results support the applicability of a two‐component cascade model for integrated cerebrovascular regulation and suggest that serial interactions between macrovascular and microvascular regulatory mechanisms jointly shape the frequency‐dependent propagation of arterial pressure to brain‐tissue oxygenation dynamics. image Key points Cerebral blood flow is stabilized by coordinated regulation across large arteries and microvessels, but their dynamic interaction has not been experimentally modelled. We examined whether a two‐component cascade model linking upstream dynamic cerebral autoregulation and downstream microvascular function can explain how blood pressure oscillations influence cortical oxygenation. In 41 healthy adults, we recorded beat‐to‐beat blood pressure, middle cerebral artery blood flow velocity and near‐infrared spectroscopy‐derived oxygenation during rest and sit–stand manoeuvres, and analysed them using transfer function analysis. Gains, phases and coherences derived from the cascade model closely matched those from the direct blood pressure–O 2 Hb relationship, particularly under forced oscillations during sit–stand, demonstrating the model's physiological relevance. The cascade model provides a mechanistic framework to separate and quantify large‐ and small‐vessel contributions to cerebral blood flow regulation, with potential application in future studies of ageing and cerebrovascular disease.

Abstract Background The van Herk margin formula, derived for 3‐D conformal radiotherapy with a uniform 3.2 mm dose penumbra and no intrinsic dose buffer, remains widely used to design CTV‐to‐PTV expansions in contemporary image‐guided prostate radiotherapy. However, coplanar VMAT techniques often feature broader penumbrae and explicit PTV–isodose clearances, potentially violating the assumptions underlying the original formulation and leading to overly conservative margins. Purpose We investigated whether the widely adopted van Herk margin formula overestimates clinical target volume (CTV)‐to‐planning target volume (PTV) expansions for contemporary coplanar volumetric modulated arc therapy (VMAT) prostate treatments. Methods Fifty consecutive intact‐prostate VMAT radiotherapy plans (two coplanar arcs; clinical margins 3 mm, except for 2 mm posterior) were exported. Direction‐specific 90% isodose–to‐PTV gaps and penumbra widths were measured. Candidate anisotropic margins were tested by eroding the PTV to create CTV_eval. Monte‐Carlo simulations combined systematic (Σ) shifts with Gaussian random (σ′) blurring kernels of 0–2 mm were performed. Acceptability criteria of (i) CTV Dmin0.03 cc ≥ 90% Rx in ≥ 90% of simulated scenarios or (ii) population tumor‐control probability (TCP) loss < 1 % were used. Results VMAT plans exhibited intrinsic 90% isodose clearances of 3–5 mm laterally/anteriorly and 1–2 mm superior–inferiorly, while axial‐plane penumbras were up to fivefold broader than van Herk's assumption. With a [0, 0, 2] mm (LR/AP/SI) margin, ≥ 90% of patients maintained Dmin0.03 cc ≥ 90% Rx provided Σ lay within an ellipsoid of [2.0, 1.5, 1.8] mm and σ′ ≤ [1.5, 2.0, 1.5] mm. Under TCP criteria the safe Σ ellipsoid for high‐risk disease was [2.5, 1.9, 2.2] mm, while low‐intermediate risk was even less sensitive. Conclusions For image‐guided coplanar VMAT prostate radiotherapy, an anisotropic [0, 0, 2] mm CTV‐to‐PTV margin is sufficient for target coverage. A modified margin expression that subtracts the measured isodose–to‐PTV gap and uses reduced random‐error coefficients better reflects modern practice.

ABSTRACT Cataract is a leading cause of visual impairment worldwide, and its prevalence is increasing with population aging. The majority are age‐related cataracts (ARC), clinically classified into nuclear, cortical, and posterior subcapsular cataracts (PSC) by opacity location. Mechanisms of cataractogenesis remain incompletely understood. While cortical and nuclear cataracts are largely attributed to crystallin aggregation, such protein‐centric mechanisms fail to explain the early onset and axial location of PSC. Morphologically, PSC resembles posterior capsule opacification (PCO), a secondary cataract driven by epithelial–mesenchymal transition (EMT) of lens epithelial cells (LECs), suggesting LEC‐EMT may also contribute to PSC. Using clinically stratified human lens samples, we confirmed EMT marker expression across PSC subtypes. Transcriptomic profiling revealed that LECs, the lens's sole metabolically active cells, in age‐related PSC (ARC‐PSC), compared with age‐related nuclear cataract (ANC) and clear lenses, exhibit elevated EMT signatures tightly linked to senescence‐associated inflammatory signaling. Aqueous humor (AqH) profiling demonstrated a pro‐inflammatory milieu across PSC subtypes, with IL‐17A uniquely elevated in ARC‐PSC, consistent with transcriptomic findings. Integrated analyses support a model in which senescence functions as an upstream driver, whereby senescent LECs release SASP factors, including IL‐17A, that activate NF‐κB signaling to amplify inflammation, reinforce senescence, and drive EMT. In vitro, senolysis and IL‐17A blockade disrupted this loop, attenuating senescence‐ and EMT‐associated phenotypes. Collectively, our study demonstrates that senescent LECs sustain an IL‐17A–NF‐κB circuit that drives EMT and accelerates ARC‐PSC progression, positioning ARC‐PSC as a unique human context to study senescence‐induced epithelial remodeling in aging tissues.

Background: Acute myeloid leukemia (AML) with CBFB::MYH11 fusion and myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions (MLN-TK) are genetically defined and typically mutually exclusive entities. Case Presentation: We report a unique case of de novo AML harboring two clonal, transcriptionally active class-defining fusions: CBFB::MYH11 and GOLGA4::PDGFRB. A 61-year-old woman presented with leukocytosis with neutrophilia, eosinophilia, and monocytosis; circulating blasts; and a markedly hypercellular marrow. Cytogenetic analysis revealed inv(16)(p13.1q22) and t(3;5)(p21;q32) in all 20 metaphases, and RNA sequencing confirmed expression of both CBFB::MYH11 and GOLGA4::PDGFRB fusions. In addition, an oncogenic WT1 frameshift variant was identified. Hematopathologic findings were largely consistent with AML with CBFB::MYH11 fusion but exhibited features reminiscent of PDGFRB-rearranged MLN-TK. The patient achieved complete remission following the standard 7 + 3 induction chemotherapy regimen for AML with gemtuzumab ozogamicin. Conclusions: This case illustrates the diagnostic challenges posed by concomitant class-defining alterations in hematologic neoplasms and underscores the importance of integrated genomic assessment.

Abstract Purpose To develop and implement an in‑house treatment‑management platform to improve communication, data accessibility, and task tracking across a radiation oncology department. Methods We developed Capsule, a custom software platform that centralizes patient data from the ARIA oncology information system (Varian Medical Systems, Palo Alto, United States), and integrates it with data from Outlook (Microsoft, Redmond, United States), spreadsheets, and manual inputs. Built using C#, SQL, and the .NET framework, it features a graphical interface in XAML with twelve modular tools to support workflows across a large multi‐modality department. A formal validation, feedback, and maintenance cycle was established. Its impact on workflow efficiency was evaluated using average CarePath task duration before and after implementation, supplemented by user interviews and surveys. Results The Department Schedule, Treatment Planning and On‐Treatment Whiteboard, Spreadsheet, and various workload tracking modules emerged as the most frequently used among dosimetrists surveyed.The Whiteboard module consolidates planning metadata for streamlined workflows. Workload and scheduling modules help distribute tasks fairly. The Department Schedule module centralizes daily role and contact information. The Spreadsheet module allows dosimetrists to identify a reference for unique plans and provides secure access to large exportable tabulated patient data and clinical trends. Other modules support proton down‐time replanning and special procedure physics assignment. One year after Capsule's implementation, most tasks in the external beam radiation therapy workflow experienced a reduction in average duration. Discussion Capsule streamlines workflows by integrating multiple tools into a single platform, supporting urgent scenarios, and improving task hand‐off. Its modular design allows customization to local workflows, but implementation must be guided by institutional oversight and formal quality management to ensure data security and compliance. Conclusion Capsule can provide a solution for improved workflow efficiency, communication, and interdisciplinary coordination. By democratizing access to routine and retrospective data, it supports treatment planning, scheduling, and quality improvement. Ongoing updates are essential as clinical practices evolve.

ABSTRACT Introduction Heart failure with preserved ejection fraction (HFpEF) accounts for about half of the cases of heart failure. HFpEF and atrial fibrillation (AF) often coexist and share similar risk factors. The objective of this study is to examine the differences in risk of clinical outcomes among drug refractory AF patients with concomitant HFpEF treated with catheter ablation (CA) versus antiarrhythmic drugs (AADs). Methods Using the Optum PanTher Electronic Health Record (EHR) database, adult HF patients with left ventricular ejection fraction (LVEF) ≥ 50% and an AF diagnosis with a history of AAD prescription between January 2014 and March 2021 were identified. Patients were classified into CA or AAD groups based on their subsequent treatment for AF. The primary outcome of interest included a composite of AF/atrial flutter (AFL)/atrial tachycardia‐related inpatient admissions and electrical cardioversions in the 57–730 days post‐index treatment period (follow‐up extended to 1095 days for sub‐analysis). Overall HF‐related admissions and systolic HF‐related admissions were assessed as secondary outcomes. Inverse probability of treatment weighting (IPTW) of propensity scores was used to balance the two cohorts on study covariates. Cox regression analyses were performed to examine outcomes in the covariate‐balanced cohorts. Results The final sample included 586 CA and 1436 AAD patients. The cohorts were well balanced on patient demographics and clinical characteristics after applying IPTW. Patients treated with CA had a significantly lower rate of primary composite outcome as compared to those treated with AADs (15.4% vs. 24.9%, log‐rank p test = 0.001). Cox model revealed a 34% lower risk of atrial arrhythmia related admissions and cardioversion among patients treated with CA versus AADs in the 57–730 days post‐index treatment period (Hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.50–0.87, p = 0.003). There were no significant differences in HF and systolic HF‐related admissions between the two groups (except in the subgroup analysis of patients < 70 years of age, patients with paroxysmal AF, and patients with persistent AF). Similar results were observed in sub‐analyses with 57–1095 days of follow‐up. Conclusion Among drug refractory AF patients with concomitant HFpEF, CA was shown to reduce the risk of recurrent arrhythmias as compared to AAD continuation.

Abstract Objective High-frequency oscillations (HFOs) are highly specific biomarkers of epileptogenic tissue, yet their noninvasive localization remains challenging due to their brief duration, low amplitude, and poor signal-to-noise ratio. Here, we introduce TH-DeepSIF, a transformer-based deep learning framework trained on biologically realistic neural mass model simulations, to robustly perform HFO source imaging from scalp EEG. Methods TH-DeepSIF was evaluated in simulated single- and dual-source HFO scenarios, where it was tasked with recovering both the spatial location and temporal dynamics of HFO generators under increasing spatiotemporal complexity. We further validated TH-DeepSIF in 25 patients with drug-resistant epilepsy by comparing EEG source imaged HFO sources against surgical resection regions. Results TH-DeepSIF accurately recovered both the spatial location and temporal dynamics of simulated HFO generators, achieving low localization error and strong waveform correspondence with ground truth. TH-DeepSIF localization for pathological HFOs (pHFOs, or spike ripples) demonstrated strong agreement with surgical resection regions, achieving a median localization error of 11.9 mm and specificity of 0.896. Compared with all HFOs (aHFOs), pHFO-based source imaging showed significantly stronger spatial correspondence with resection regions, significantly smaller localization error, and higher precision, sensitivity, geometric mean, and F1 score. Significance These findings demonstrate that TH-DeepSIF provides a robust, data-driven framework for noninvasive HFO source imaging with improved anatomical specificity and enhanced clinical utility for presurgical evaluation using scalp EEG. Moreover, they show that pathological HFOs (spike ripples )—rather than general HFOs—serve as robust EEG biomarkers for accurate localization of the epileptogenic zone. Key Points A fully data-driven, parameter-free framework for noninvasive HFO source imaging using scalp EEG. Pathological HFO source maps exhibit strong spatial concordance with both the surgical resection region and the seizure onset zone. Source imaging based on pathological HFOs consistently outperforms imaging based on all detected HFOs.