Impact of proton PBS machine operating parameters on the effectiveness of layer rescanning for interplay effect mitigation in lung SBRT treatment.

BACKGROUND: Rescanning is a common technique used in proton pencil beam scanning to mitigate the interplay effect. Advances in machine operating parameters across different generations of particle therapy systems have led to improvements in beam delivery time (BDT). However, the potential impact of these improvements on the effectiveness of rescanning remains an underexplored area in the existing research. METHODS: We systematically investigated the impact of proton machine operating parameters on the effectiveness of layer rescanning in mitigating interplay effect during lung SBRT treatment, using the CIRS phantom. Focused on the Hitachi synchrotron particle therapy system, we explored machine operating parameters from our institution's current (2015) and upcoming systems (2025A and 2025B). Accumulated dynamic 4D dose were reconstructed to assess the interplay effect and layer rescanning effectiveness. RESULTS: Achieving target coverage and dose homogeneity within 2% deviation required 6, 6, and 20 times layer rescanning for the 2015, 2025A, and 2025B machine parameters, respectively. Beyond this point, further increasing the number of layer rescanning did not further improve the dose distribution. BDTs without rescanning were 50.4, 24.4, and 11.4 s for 2015, 2025A, and 2025B, respectively. However, after incorporating proper number of layer rescanning (six for 2015 and 2025A, 20 for 2025B), BDTs increased to 67.0, 39.6, and 42.3 s for 2015, 2025A, and 2025B machine parameters. Our data also demonstrated the potential problem of false negative and false positive if the randomness of the respiratory phase at which the beam is initiated is not considered in the evaluation of interplay effect. CONCLUSION: The effectiveness of layer rescanning for mitigating interplay effect is affected by machine operating parameters. Therefore, past clinical experiences may not be applicable to modern machines.

Racial and Ethnic Disparities in Years of Potential Life Loss Among Patients With Cirrhosis During the COVID-19 Pandemic in the United States.

INTRODUCTION: Our aim was to evaluate the impact of race/ethnicity on cirrhosis-related premature death during the COVID-19 pandemic. METHODS: We obtained cirrhosis-related death data (n = 872,965, January 1, 2012-December 31, 2021) from the US National Vital Statistic System to calculate age-standardized mortality rates and years of potential life lost (YPLL) for premature death aged 25-64 years. RESULTS: Significant racial/ethnic disparity in cirrhosis-related age-standardized mortality rates was noted prepandemic but widened during the pandemic, with the highest excess YPLL for the non-Hispanic American Indian/American Native (2020: 41.0%; 2021: 68.8%) followed by other minority groups (28.7%-45.1%), and the non-Hispanic White the lowest (2020: 20.7%; 2021: 31.6%). COVID-19 constituted >30% of the excess YPLLs for Hispanic and non-Hispanic American Indian/American Native in 2020, compared with 11.1% for non-Hispanic White. DISCUSSION: Ethnic minorities with cirrhosis experienced a disproportionate excess death and YPLLs in 2020-2021.

Oral cancer patients achieve comparable survival at high safety-net burden hospitals.

PURPOSE: To evaluate the impact of hospital safety-net burden and social demographics on the overall survival of patients with oral cavity squamous cell carcinoma. MATERIALS AND METHODS: We identified 48,176 oral cancer patients diagnosed between the years 2004 to 2015 from the National Cancer Database and categorized treatment facilities as no, low, or high safety-net burden hospitals based on the percentage of uninsured or Medicaid patients treated. Using the Kaplan Meier method and multivariate analysis, we examined the effect of hospital safety-net burden, sociodemographic variables, and clinical factors on overall survival. RESULTS: Of the 1269 treatment facilities assessed, the median percentage of uninsured/Medicaid patients treated was 0% at no, 11.6% at low, and 23.5% at high safety-net burden hospitals and median survival was 68.6, 74.8, and 55.0 months, respectively (p < 0.0001). High safety-net burden hospitals treated more non-white populations (15.4%), lower median household income (<$30,000) (23.2%), and advanced stage cancers (AJCC III/IV) (54.6%). Patients treated at low (aHR = 0.97; 95% CI = 0.91-1.04, p = 0.405) and high (aHR = 1.05; 95% CI = 0.98-1.13, p = 0.175) safety-net burden hospitals did not experience worse survival outcomes compared to patients treated at no safety-net burden hospitals. CONCLUSION: High safety-net burden hospitals treated more oral cancer patients of lower socioeconomic status and advanced disease. Multivariate analysis showed high safety-net burden hospitals achieved comparable patient survival to lower burden hospitals.

Interest, Concerns, and Attitudes Among Men Who Have Sex With Men and Health Care Providers Toward Prophylactic Use of Doxycycline Against Chlamydia trachomatis Infections and Syphilis.

BACKGROUND: Prophylactic administration of doxycycline is regarded as a potential new public health strategy to combat the rising rates of Chlamydia trachomatis infections and syphilis among men who have sex with men. We conducted a survey-based study to evaluate how community members and health care providers in Southern California would perceive doxycycline preexposure/postexposure prophylaxis (PrEP/PEP) to predict its acceptability and identify potential areas of concern. METHODS: We conducted an online cross-sectional survey among community members who identify as men who have sex with men and health care providers with prescribing authority in Southern California to investigate the current attitudes toward doxycycline PrEP/PEP, including their willingness to accept. We analyzed the data using descriptive statistics and binary logistic regression. RESULTS: Among 212 enrolled community member participants, 67.5% indicated they would take doxycycline PrEP/PEP if offered by their provider. Higher acceptability was significantly associated with several characteristics, including recent history of bacterial sexually transmitted infection diagnosis and current use of HIV PrEP. For health care providers, 89.5% of 76 enrolled participants expressed willingness to prescribe doxycycline PrEP/PEP to their patients if recommended by the Centers for Disease Control and Prevention, but only 43.4% were willing if not. Both community members and health care providers demonstrated high levels of concern toward possible drug resistance. CONCLUSIONS: Doxycycline PrEP/PEP as a preventive strategy against chlamydial infections and syphilis would likely be accepted among community members and health care providers. Clear guidelines from public health officials and further clarification on the strategy's potential impact on developing drug resistance may be necessary to ensure successful implementation.

A national cancer database analysis on stereotactic body radiation therapy of head and neck cancers.

BACKGROUND: To evaluate demographic, clinicopathological, treatment factors including biological effective radiation dose (BED) that influence overall survival in head and neck cancer (HNC) patients treated with stereotactic body radiation therapy (SBRT). METHODS: Between 2004 and 2015, 591 SBRT-treated HNC patients were identified from the National Cancer Data Base. A BED using an alpha/beta ratio of 10 (BED10), was used to compare dose fractionation of different SBRT regimens. Overall survival was estimated using the Kaplan Meier method, and log-rank tests were used to determine statistical significance. Cox regression modeling was used to compute crude and adjusted hazard ratios (HR) with 95% confidence intervals (CI). RESULTS: Median follow-up was 11.9 (interquartile range, 5.5 to 26.7) months. The 5-year overall survival rate was 15.5%. On multivariate analysis, older age, Charlson-Deyo comorbidity score ≥ 1, history of cancer, tumor, nodal and metastatic stage, and receiving treatment at academic/research program were associated with poor survival. Compared to SBRT alone, superior survival was observed with SBRT with chemotherapy, surgery with SBRT, but not surgery with SBRT and chemotherapy. Improved survival was observed with aa BED10 of ≥59.5 Gy (adjusted HR 0.57, 95% CI 0.46-0.70, P < 0.0001). CONCLUSIONS: Factors affecting associated with worse survival in HNC patients treated with SBRT included older age, patient comorbidities, advanced tumor stage, cancer history, and lower biological effective SBRT dose. LEVEL OF EVIDENCE: 2b (individual cohort study).

Direct tumor visual feedback during free breathing in 0.35T MRgRT.

To present a tumor motion control system during free breathing using direct tumor visual feedback to patients in 0.35 T magnetic resonance-guided radiotherapy (MRgRT). We present direct tumor visualization to patients by projecting real-time cine MR images on an MR-compatible display system inside a 0.35 T MRgRT bore. The direct tumor visualization included anatomical images with a target contour and an auto-segmented gating contour. In addition, a beam-status sign was added for patient guidance. The feasibility was investigated with a six-patient clinical evaluation of the system in terms of tumor motion range and beam-on time. Seven patients without visual guidance were used for comparison. Positions of the tumor and the auto-segmented gating contour from the cine MR images were used in probability analysis to evaluate tumor motion control. In addition, beam-on time was recorded to assess the efficacy of the visual feedback system. The direct tumor visualization system was developed and implemented in our clinic. The target contour extended 3 mm outside of the gating contour for 33.6 ± 24.9% of the time without visual guidance, and 37.2 ± 26.4% of the time with visual guidance. The average maximum motion outside of the gating contour was 14.4 ± 11.1 mm without and 13.0 ± 7.9 mm with visual guidance. Beam-on time as a percentage was 43.9 ± 15.3% without visual guidance, and 48.0 ± 21.2% with visual guidance, but was not significantly different (P = 0.34). We demonstrated the clinical feasibility and potential benefits of presenting direct tumor visual feedback to patients in MRgRT. The visual feedback allows patients to visualize and attempt to minimize tumor motion in free breathing. The proposed system and associated clinical workflow can be easily adapted for any type of MRgRT.

Parasite stress and pathogen avoidance relate to distinct dimensions of political ideology across 30 nations.

People who are more avoidant of pathogens are more politically conservative, as are nations with greater parasite stress. In the current research, we test two prominent hypotheses that have been proposed as explanations for these relationships. The first, which is an intragroup account, holds that these relationships between pathogens and politics are based on motivations to adhere to local norms, which are sometimes shaped by cultural evolution to have pathogen-neutralizing properties. The second, which is an intergroup account, holds that these same relationships are based on motivations to avoid contact with outgroups, who might pose greater infectious disease threats than ingroup members. Results from a study surveying 11,501 participants across 30 nations are more consistent with the intragroup account than with the intergroup account. National parasite stress relates to traditionalism (an aspect of conservatism especially related to adherence to group norms) but not to social dominance orientation (SDO; an aspect of conservatism especially related to endorsements of intergroup barriers and negativity toward ethnic and racial outgroups). Further, individual differences in pathogen-avoidance motives (i.e., disgust sensitivity) relate more strongly to traditionalism than to SDO within the 30 nations.

CHARACTERIZATION OF THE MIDDLE CAPILLARY PLEXUS USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN HEALTHY AND DIABETIC EYES.

PURPOSE: To assess the ability of optical coherence tomography angiography to image the retinal middle capillary plexus (MCP), and to characterize the MCP as a unique vascular network separate from the superficial and deep capillary plexus (DCP). METHODS: Healthy and diabetic eyes were imaged using the Avanti XR optical coherence tomography angiography instrument (Optovue Inc, Fremont, CA). Using manual segmentation of the retinal layers, the authors generated en face angiograms to distinguish the three capillary plexuses (superficial capillary plexus, MCP, DCP). RESULTS: In healthy eyes, arterioles gave rise to distinct branches in the MCP, and venules gave rise to prominent vortex like branches in the DCP. The foveal avascular zone was most well-defined at the level of the MCP, and had a larger area in the DCP. In diabetic eyes, the three capillary plexuses showed varying degrees of nonperfusion, including variable shapes and extent of the foveal avascular zone, with loss of border integrity at the MCP. Microaneurysms appeared in all the three capillary plexuses. CONCLUSION: Using customized segmentation analysis in optical coherence tomography angiography, the authors demonstrate that the MCP is qualitatively and functionally distinct from the superficial capillary plexus and DCP, which may help clarify the pathogenesis of different middle retinal ischemic entities and provide new insights into retinal ischemia in diabetic retinopathy.

Image-domain shading correction for cone-beam CT without prior patient information.

In the era of high-precision radiotherapy, cone-beam CT (CBCT) is frequently utilized for on-board treatment guidance. However, CBCT images usually contain severe shading artifacts due to strong photon scatter from illumination of a large volume and non-optimized patient-specific data measurements, limiting the full clinical applications of CBCT. Many algorithms have been proposed to alleviate this problem by data correction on projections. Sophisticated methods have also been designed when prior patient information is available. Nevertheless, a standard, efficient, and effective approach with large applicability remains elusive for current clinical practice. In this work, we develop a novel algorithm for shading correction directly on CBCT images. Distinct from other image-domain correction methods, our approach does not rely on prior patient information or prior assumption of patient data. In CBCT, projection errors (mostly from scatter and non-ideal usage of bowtie filter) result in dominant low-frequency shading artifacts in image domain. In circular scan geometry, these artifacts often show global or local radial patterns. Hence, the raw CBCT images are first preprocessed into the polar coordinate system. Median filtering and polynomial fitting are applied on the transformed image to estimate the low-frequency shading artifacts (referred to as the bias field) angle-by-angle and slice-by-slice. The low-pass filtering process is done firstly along the angular direction and then the radial direction to preserve image contrast. The estimated bias field is then converted back to the Cartesian coordinate system, followed by 3D low-pass filtering to eliminate possible high-frequency components. The shading-corrected image is finally obtained as the uncorrected volume divided by the bias field. The proposed algorithm was evaluated on CBCT images of a pelvis patient and a head patient. Mean CT number values and spatial non-uniformity on the reconstructed images were used as image quality metrics. Within selected regions of interest, the average CT number error was reduced from around 300 HU to 42 and 38 HU, and the spatial nonuniformity error was reduced from above 17.5% to 2.1% and 1.7% for the pelvis and the head patients, respectively. As our method suppresses only low-frequency shading artifacts, patient anatomy and contrast were retained in the corrected images for both cases. Our shading correction algorithm on CBCT images offers several advantages. It has a high efficiency, since it is deterministic and directly operates on the reconstructed images. It requires no prior information or assumptions, which not only achieves the merits of CBCT-based treatment monitoring by retaining the patient anatomy, but also facilitates its clinical use as an efficient image-correction solution.

A Listeria monocytogenes-based vaccine that secretes sand fly salivary protein LJM11 confers long-term protection against vector-transmitted Leishmania major.

Cutaneous leishmaniasis is a sand fly-transmitted disease characterized by skin ulcers that carry significant scarring and social stigmatization. Over the past years, there has been cumulative evidence that immunity to specific sand fly salivary proteins confers a significant level of protection against leishmaniasis. In this study, we used an attenuated strain of Listeria monocytogenes as a vaccine expression system for LJM11, a sand fly salivary protein identified as a good vaccine candidate. We observed that mice were best protected against an intradermal needle challenge with Leishmania major and sand fly saliva when vaccinated intravenously. However, this protection was short-lived. Importantly, groups of vaccinated mice were protected long term when challenged with infected sand flies. Protection correlated with smaller lesion size, fewer scars, and better parasite control between 2 and 6 weeks postchallenge compared to the control group of mice vaccinated with the parent L. monocytogenes strain not expressing LJM11. Moreover, protection correlated with high numbers of CD4(+), gamma interferon-positive (IFN-γ(+)), tumor necrosis factor alpha-positive/negative (TNF-α(+/-)), interleukin-10-negative (IL-10(-)) cells and low numbers of CD4(+) IFN-γ(+/-) TNF-α(-) IL-10(+) T cells at 2 weeks postchallenge. Overall, our data indicate that delivery of LJM11 by Listeria is a promising vaccination strategy against cutaneous leishmaniasis inducing long-term protection against ulcer formation following a natural challenge with infected sand flies.

Optimal Self-Care for Surgeons: Sleep, Diet, and Exercise.

BACKGROUND: Surgeons face intense stress, causing hormonal imbalances that harm their health, leading to burnout, chronic illness, and shorter lifespans due to their demanding careers. PURPOSE: This study explores self-care strategies focusing on sleep, nutrition, and exercise to help surgeons reduce stress and improve their overall well-being and quality of life. RESEARCH DESIGN: A thorough literature review of physiological, metabolic, and psychological principles informed the development of a structured self-care approach. DATA COLLECTION AND/OR ANALYSIS: We reviewed existing research on brain-body interactions, highlighting hormonal balance, nutrition, and exercise to mitigate chronic stress. RESULTS: The review underscores the importance of quality sleep for hormonal balance and overall health. Proper nutrition, emphasizing balanced macronutrients and meal timing, supports health. Exercise should be 80% low-intensity aerobic activities, with 20% high-intensity. Combining these elements strengthens resistance to chronic stress and enhances health. CONCLUSIONS: A structured self-care approach, prioritizing sleep, followed by nutrition and exercise, effectively reduces stress among surgeons. This sequence improves well-being and quality of life. Surgeons should focus on consistent sleep, balanced nutrition, and regular low-intensity exercise to enhance resilience and achieve a fulfilling professional life.

Does Epidural Corticosteroid Application During Spinal Surgery Reduce Postoperative Pain?: An Adjunct to Multimodal Analgesia.

STUDY DESIGN: A prospective, randomized, placebo-controlled, double-blinded study. OBJECTIVE: To examine the effect of intraoperative epidural administration of Depo-Medrol on postoperative back pain and radiculitis symptoms in patients undergoing Transforaminal Lumbar Interbody Fusion (TLIF). SUMMARY OF BACKGROUND DATA: Postoperative pain is commonly experienced by patients undergoing spinal fusion surgery. Adequate management of intense pain is necessary to encourage early ambulation, increase patient satisfaction, and limit opioid consumption. Intraoperative steroid application has been shown to improve postoperative pain in patients undergoing lumbar decompression surgeries. There have been no studies examining the effect of epidural steroids on both back pain and radicular pain in patients undergoing TLIF. METHOD: In all, 151 patients underwent TLIF surgery using rh-BMP2 with 3 surgeons at a single institution. Of those, 116 remained in the study and were included in the final analysis. Based on a 1:1 randomization, a collagen sponge saturated with either Saline (1 cc) or Depo-Medrol (40 mg/1 cc) was placed at the annulotomy site on the TLIF level. Follow-up occurred on postoperative days 1, 2, 3, 7, and postoperative months 1, 2, and 3. Lumbar radiculopathy was measured by a modified symptom- and laterality-specific Visual Analog Scale (VAS) regarding the severity of back pain and common radiculopathy symptoms. RESULTS: The patients who received Depo-Medrol, compared with those who received saline, experienced significantly less back pain on postoperative days 1, 2, 3, and 7 ( P <0.05). There was no significant difference in back pain beyond day 7. Radiculopathy-related symptoms such as leg pain, numbness, tingling, stiffness, and weakness tended to be reduced in the steroid group at most time points. CONCLUSION: This study provides Level 1 evidence that intraoperative application of Depo-Medrol during a TLIF surgery with rh-BMP2 significantly reduces back pain for the first week after TLIF surgery. The use of epidural Depo-Medrol may be a useful adjunct to multimodal analgesia for pain relief in the postoperative period.

In Situ Quantification of Carbonate Species Concentrations, pH, and pCO2 in Calcite Fluid Inclusions Using Confocal Raman Spectroscopy.

Carbonate minerals are globally distributed on the modern and ancient Earth and are abundant in terrestrial and marine depositional environments. Fluid inclusions hosted by calcite retain primary signatures of the source fluid geochemistry at the time of mineral formation (i.e., pCO2) and can be used to reconstruct paleoenvironments. Confocal laser Raman spectroscopy provides a quick, nondestructive approach to measuring the constituents of fluid inclusions in carbonates and is a reliable method for qualitatively determining composition in both the aqueous and gas phases. Here, we demonstrate a method for accurately quantifying bicarbonate and carbonate ion concentrations (down to 20 mM) and pH (7-11) from calcite fluid inclusions using confocal Raman spectroscopy. Instrument calibrations for carbonate (CO32-) and bicarbonate (HCO3-) concentrations and pH were performed using stock solutions. We show that the calcite host mineral does not affect the accurate quantification of carbonate solution concentrations and that these parameters can be used to estimate the pH and pCO2 of a solution entrapped within a fluid inclusion. We apply the technique to Icelandic spar calcite and find a [CO32-] = 0.11, [HCO3-] = 0.17, pH = 10.1, and CO2 parts per million = 2217. The presence of gaseous Raman bands for CO2, CH4, and H2S suggests that the mineral precipitated in a reducing environment.

An International Retrospective Early Natural History Study of LAMA2-Related Dystrophies.

Background: LAMA2-related dystrophies (LAMA2-RDs) represent one of the most common forms of congenital muscular dystrophy and have historically been classified into two subtypes: complete or partial deficiency of laminin-211 (merosin). Patients with LAMA2-RD with the typical congenital phenotype manifest severe muscle weakness, delayed motor milestones, joint contractures, failure to thrive, and progressive respiratory insufficiency. Objective: While a comprehensive prospective natural history study has been performed in LAMA2-RD patients over 5 years of age, the early natural history of patients with LAMA2-RD 5 years and younger has not been comprehensively characterized. Methods: We extracted retrospective data for patients with LAMA2-RD ages birth through 5 years via the Congenital Muscle Disease International Registry (CMDIR). We analyzed the data using a phenotypic classification based on maximal motor milestones to divide patients into two phenotypic groups: "Sit" for those patients who attained that ability to remain seated and "Walk" for those patients who attained the ability to walk independently by 3.5 years of age. Results: Sixty patients with LAMA2-RD from 10 countries fulfilled the inclusion criteria. Twenty-four patients had initiated non-invasive ventilation by age 5 years. Hospitalizations during the first years of life were often related to respiratory insufficiency. Feeding/nutritional difficulties and orthopedic issues were commonly reported. Significant elevations of creatine kinase (CK) observed during the neonatal period declined rapidly within the first few months of life. Conclusions: This is the largest international retrospective early natural history study of LAMA2-RD to date, contributing essential data for understanding early clinical findings in LAMA2-RD which, along with the data being collected in international, prospective early natural history studies, will help to establish clinical trial readiness. Our proposed nomenclature of LAMA2-RD1 for patients who attain the ability to sit (remain seated) and LAMA2-RD2 for patients who attain the ability to walk independently is aimed at further improving LAMA2-RD classification.

The InterVision Framework: An Enhanced Fine-Tuning Deep Learning Strategy for Auto-Segmentation in Head and Neck.

Adaptive radiotherapy (ART) workflows are increasingly adopted to achieve dose escalation and tissue sparing under dynamic anatomical conditions. However, recontouring and time constraints hinder the implementation of real-time ART workflows. Various auto-segmentation methods, including deformable image registration, atlas-based segmentation, and deep learning-based segmentation (DLS), have been developed to address these challenges. Despite the potential of DLS methods, clinical implementation remains difficult due to the need for large, high-quality datasets to ensure model generalizability. This study introduces an InterVision framework for segmentation. The InterVision framework can interpolate or create intermediate visuals between existing images to generate specific patient characteristics. The InterVision model is trained in two steps: (1) generating a general model using the dataset, and (2) tuning the general model using the dataset generated from the InterVision framework. The InterVision framework generates intermediate images between existing patient image slides using deformable vectors, effectively capturing unique patient characteristics. By creating a more comprehensive dataset that reflects these individual characteristics, the InterVision model demonstrates the ability to produce more accurate contours compared to general models. Models are evaluated using the volumetric dice similarity coefficient (VDSC) and the Hausdorff distance 95% (HD95%) for 18 structures in 20 test patients. As a result, the Dice score was 0.81 ± 0.05 for the general model, 0.82 ± 0.04 for the general fine-tuning model, and 0.85 ± 0.03 for the InterVision model. The Hausdorff distance was 3.06 ± 1.13 for the general model, 2.81 ± 0.77 for the general fine-tuning model, and 2.52 ± 0.50 for the InterVision model. The InterVision model showed the best performance compared to the general model. The InterVision framework presents a versatile approach adaptable to various tasks where prior information is accessible, such as in ART settings. This capability is particularly valuable for accurately predicting complex organs and targets that pose challenges for traditional deep learning algorithms.

Enhanced IDOL segmentation framework using personalized hyperspace learning IDOL.

BACKGROUND: Adaptive radiotherapy (ART) workflows have been increasingly adopted to achieve dose escalation and tissue sparing under shifting anatomic conditions, but the necessity of recontouring and the associated time burden hinders a real-time or online ART workflow. In response to this challenge, approaches to auto-segmentation involving deformable image registration, atlas-based segmentation, and deep learning-based segmentation (DLS) have been developed. Despite the particular promise shown by DLS methods, implementing these approaches in a clinical setting remains a challenge, namely due to the difficulty of curating a data set of sufficient size and quality so as to achieve generalizability in a trained model. PURPOSE: To address this challenge, we have developed an intentional deep overfit learning (IDOL) framework tailored to the auto-segmentation task. However, certain limitations were identified, particularly the insufficiency of the personalized dataset to effectively overfit the model. In this study, we introduce a personalized hyperspace learning (PHL)-IDOL segmentation framework capable of generating datasets that induce the model to overfit specific patient characteristics for medical image segmentation. METHODS: The PHL-IDOL model is trained in two stages. In the first, a conventional, general model is trained with a diverse set of patient data (n = 100 patients) consisting of CT images and clinical contours. Following this, the general model is tuned with a data set consisting of two components: (a) selection of a subset of the patient data (m < n) using the similarity metrics (mean square error (MSE), peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), and the universal quality image index (UQI) values); (b) adjust the CT and the clinical contours using a deformed vector generated from the reference patient and the selected patients using (a). After training, the general model, the continual model, the conventional IDOL model, and the proposed PHL-IDOL model were evaluated using the volumetric dice similarity coefficient (VDSC) and the Hausdorff distance 95% (HD95%) computed for 18 structures in 20 test patients. RESULTS: Implementing the PHL-IDOL framework resulted in improved segmentation performance for each patient. The Dice scores increased from 0.81 ± $ \pm $ 0.05 with the general model, 0.83 ± 0.04 $ \pm 0.04$ for the continual model, 0.83 ± 0.04 $ \pm 0.04$ for the conventional IDOL model to an average of 0.87 ± 0.03 $ \pm 0.03$ with the PHL-IDOL model. Similarly, the Hausdorff distance decreased from 3.06 ± 0.99 $ \pm 0.99$ with the general model, 2.84 ± 0.69 $ \pm 0.69$ for the continual model, 2.79 ± 0.79 $ \pm 0.79$ for the conventional IDOL model and 2.36 ± 0.52 $ \pm 0.52$ for the PHL-IDOL model. All the standard deviations were decreased by nearly half of the values comparing the general model and the PHL-IDOL model. CONCLUSION: The PHL-IDOL framework applied to the auto-segmentation task achieves improved performance compared to the general DLS approach, demonstrating the promise of leveraging patient-specific prior information in a task central to online ART workflows.

AAPM Task Group 334: A guidance document to using radiotherapy immobilization devices and accessories in an MR environment.

Use of magnetic resonance (MR) imaging in radiation therapy has increased substantially in recent years as more radiotherapy centers are having MR simulators installed, requesting more time on clinical diagnostic MR systems, or even treating with combination MR linear accelerator (MR-linac) systems. With this increased use, to ensure the most accurate integration of images into radiotherapy (RT), RT immobilization devices and accessories must be able to be used safely in the MR environment and produce minimal perturbations. The determination of the safety profile and considerations often falls to the medical physicist or other support staff members who at a minimum should be a Level 2 personnel as per the ACR. The purpose of this guidance document will be to help guide the user in making determinations on MR Safety labeling (i.e., MR Safe, Conditional, or Unsafe) including standard testing, and verification of image quality, when using RT immobilization devices and accessories in an MR environment.

Disease-avoidance processes and stigmatization: cues of substandard health arouse heightened discomfort with physical contact.

An evolutionary approach to stigmatization suggests that disease-avoidance processes contribute to some instances of social exclusion. Disease-avoidance processes are over-inclusive, targeting even non-threatening individuals who display cues of substandard health. We investigated whether such cues motivate avoidance of physical contact in particular. In Studies 1 and 2, targets with disease (e.g., leprosy) or atypical morphologies (e.g., amputated leg, obesity) were found to arouse differentially heightened discomfort with physical (versus nonphysical) contact, whereas a criminal target (stigmatized for disease-irrelevant reasons) was found to arouse elevated discomfort for both types of contact. Study 3 used a between-subjects design that eliminated the influence of extraneous factors. A diseased target was found to arouse differentially heightened discomfort with physical (versus nonphysical) contact, and to do so more strongly than any other type of target.

Assessing the reliability of pediatric emergency medicine billing code assignment for future consideration as a proxy workload measure.

OBJECTIVES: Prediction of pediatric emergency department (PED) workload can allow for optimized allocation of resources to improve patient care and reduce physician burnout. A measure of PED workload is thus required, but to date no variable has been consistently used or could be validated against for this purpose. Billing codes, a variable assigned by physicians to reflect the complexity of medical decision making, have the potential to be a proxy measure of PED workload but must be assessed for reliability. In this study, we investigated how reliably billing codes are assigned by PED physicians, and factors that affect the inter-rater reliability of billing code assignment. METHODS: A retrospective cross-sectional study was completed to determine the reliability of billing code assigned by physicians (n = 150) at a quaternary-level PED between January 2018 and December 2018. Clinical visit information was extracted from health records and presented to a billing auditor, who independently assigned a billing code-considered as the criterion standard. Inter-rater reliability was calculated to assess agreement between the physician-assigned versus billing auditor-assigned billing codes. Unadjusted and adjusted logistic regression models were used to assess the association between covariables of interest and inter-rater reliability. RESULTS: Overall, we found substantial inter-rater reliability (AC2 0.72 [95% CI 0.64-0.8]) between the billing codes assigned by physicians compared to those assigned by the billing auditor. Adjusted logistic regression models controlling for Pediatric Canadian Triage and Acuity scores, disposition, and time of day suggest that clinical trainee involvement is significantly associated with increased inter-rater reliability. CONCLUSIONS: Our work identified that there is substantial agreement between PED physician and a billing auditor assigned billing codes, and thus are reliably assigned by PED physicians. This is a crucial step in validating billing codes as a potential proxy measure of pediatric emergency physician workload.