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This series is automatically populated with publications deposited by UC San Diego School of Medicine Department of Radiation Medicine & Applied Science researchers in accordance with the University of California’s open access policies. For more information see Open Access Policy Deposits and the UC Publication Management System.

Cover page of Arterial and Venous Thrombotic Complications in Patients with COVID-19: A Report of Three Cases

Arterial and Venous Thrombotic Complications in Patients with COVID-19: A Report of Three Cases

(2022)

Coronavirus Disease 2019 (COVID-19) has had an enormous impact on both the medical community as well as society as a whole. Research on the pathogenesis and the treatment of the disease is rapidly emerging, with new observations and hypotheses appearing daily. One aspect that has been receiving increasing attention is the occurrence of both arterial and venous thrombotic complications in patients with COVID-19. We report three cases of thromboembolic complications in patients affected by COVID-19 and discuss clinical features, pathophysiology, and the proposed approaches to management of vascular complications in these patients. Through our discussion, we also urge physicians to be vigilant for any symptoms or signs suggestive of thrombosis in patients with COVID-19.

Cover page of Routine Repeat Head CT may not be Indicated in  Patients on Anticoagulant/Antiplatelet Therapy  Following Mild Traumatic Brain Injury

Routine Repeat Head CT may not be Indicated in Patients on Anticoagulant/Antiplatelet Therapy Following Mild Traumatic Brain Injury

(2015)

Introduction: Evaluation recommendations for patients on anticoagulant and antiplatelet (ACAP) therapy that present after mild traumatic brain injury (TBI) are controversial. At our institution, an initial noncontrast head computed tomography (HCT) is performed, with a subsequent HCT performed six hours later to exclude delayed intracranial hemorrhage (ICH). This study was performed to evaluate the yield and advisability of this approach.

Methods: We performed a retrospective review of subjects undergoing evaluation for ICH after mild TBI in patients on ACAP therapy between January of 2012 and April of 2013. We assessed for the frequency of ICH on both the initial noncontrast HCT and on the routine six-hour follow-up HCT. Additionally, chart review was performed to evaluate the clinical implications of ICH, when present, and to interrogate whether pertinent clinical and laboratory data may predict the presence of ICH prior to imaging. We used multivariate generalized linear models to assess whether presenting Glasgow Coma Score (GCS), loss of consciousness (LOC), neurological or physical examination findings, international normalized ratio, prothrombin time, partial thromboplastin time, platelet count, or specific ACAP regimen predicted ICH.

Results: 144 patients satisfied inclusion criteria. Ten patients demonstrated initial HCT positive for ICH, with only one demonstrating delayed ICH on the six-hour follow-up HCT. This patient was discharged without any intervention required or functional impairment. Presenting GCS deviation (p<0.001), LOC (p=0.04), neurological examination findings (p<0.001), clopidogrel (p=0.003), aspirin (p=0.03) or combination regimen (p=0.004) use were more commonly seen in patients with ICH.

Conclusion: Routine six-hour follow-up HCT is likely not indicated in patients on ACAP therapy, as our study suggests clinically significant delayed ICH does not occur. Additionally, presenting GCS deviation, LOC, neurological examination findings, clopidogrel, aspirin or combination regimen use may predict ICH, and, in the absence of these findings, HCT may potentially be forgone altogether. [West J Emerg Med. 2015;16(1):-0.]

Laterality of Swimming-Induced Pulmonary Edema During Combat Sidestroke Assessed by Lung Ultrasound and Chest Radiography

(2026)

BACKGROUND: Swimming-induced pulmonary edema (SIPE) causes acute respiratory symptoms during strenuous water activities and has been described in military trainees and open-water swimmers. Although SIPE typically presents bilaterally, asymmetric cases may relate to swimmer position. Chest x-ray (CXR) and lung ultrasound (LUS) are used in the clinical evaluation of SIPE, but whether they show similar edema lateralization patterns relative to swimmer position is unclear. RESEARCH QUESTIONS: Is edema laterality in SIPE associated with dependent body position during combat sidestroke (CSS)? When CXR and LUS are obtained during the same SIPE episode, do they show similar edema lateralization patterns? STUDY DESIGN AND METHODS: We retrospectively analyzed 91 SIPE episodes in 82 maritime trainees. Clinical records, CXR, and LUS were reviewed to characterize edema laterality on a five-point ordinal scale. Agreement between CXR and LUS laterality scores was assessed with Cohen's weighted kappa. Associations between imaging laterality and dependent body position during CSS were evaluated using Fisher's exact test, with Cramér's V to quantify effect size. RESULTS: Imaging data were available for 89 episodes with CXR, 49 with LUS, and 47 with both. Pulmonary edema laterality was significantly associated with dependent body position for both modalities (p < 0.001; Cramér's V = 0.41). CXR and LUS showed moderate agreement (κ = 0.58, p < 0.001) using three- and five-point scales, with agreement within ± 1 category in 98% and 81% of paired comparisons, respectively. INTERPRETATION: Among trainees who developed SIPE while performing CSS, edema laterality corresponded with the swimmer's dependent body position. CXR and LUS showed similar lateralization patterns with moderate agreement when obtained during the same SIPE episode. These findings support LUS as a practical tool in field settings for characterizing edema distribution when radiography is unavailable, while CXR remains important for evaluating central abnormalities and alternative pulmonary diagnoses.

Cover page of A28-19 A Comparative Study of Lung Ultrasound and Chest X-Ray Findings in Military Trainees With Swimming-Induced Pulmonary Edema

A28-19 A Comparative Study of Lung Ultrasound and Chest X-Ray Findings in Military Trainees With Swimming-Induced Pulmonary Edema

(2026)

Abstract Rationale Swimming-induced pulmonary edema (SIPE) is a condition characterized by acute pulmonary symptoms during strenuous water activities, notably affecting military trainees and open-water swimmers. Unilateral pulmonary edema, often on the dependent side during lateral or side-down positions, suggests gravitational and regional perfusion influences. While chest x-ray (CXR) and lung ultrasound (LUS) are utilized for diagnosis, their comparative effectiveness, particularly in detecting lateralization, remains underexplored. The primary aims of this study are to compare CXR and LUS findings in patients with SIPE, determine whether the dependent side in water while performing combat sidestroke (CSS) correlates with unilateral imaging findings, and explore any differences in detection between these modalities. Addressing these objectives may improve diagnostic precision, deepen understanding of SIPE’s underlying mechanisms, and guide more effective management of affected individuals in aquatic and military training environments. Methods A retrospective review of 82 maritime trainees with SIPE which assessed clinical, radiographic, and ultrasound data to confirm pulmonary edema and its laterality. This review also examines the relationship between side-down positioning during sidestroke and imaging abnormalities. Chest radiographs and lung ultrasounds were scored with a 5-point Likert scale for side predilection. Their concordance was analyzed alongside the influence of body position on chest imaging findings. The two Likert scales were compared for association, agreement, and directionality using Chi squared, Cohen’s Kappa, and Spearman’s rank correlation. Results A significant association was observed between CXR and LUS lateralization scores (χ²=21.45, p<.001), with moderate agreement (κ = 0.57) and a strong positive correlation (ρ = 0.60). When analyzing the full five-point scale, agreement improved (κ = 0.59, ρ = 0.63) (Table 1). A significant association was seen between lung edema lateralization on imaging and body position (p < 0.001). Conclusion This study demonstrates a moderate to strong concordance between chest radiography and lung ultrasound in detecting pulmonary edema lateralization in SIPE patients. Both modalities demonstrate significant correlation between dependent side-down positioning and unilateral edema. The study’s focus on lateralization underscores the importance of positional factors during water activities. Recognizing dependence-related asymmetry in pulmonary edema suggests that positional strategies, such as switching sides during CSS, could help reduce SIPE risk. While LUS is a valuable tool in the evaluation and diagnosis of SIPE, its limitations in identifying or characterizing more centrally located lesions or alternative pathologies should be acknowledged, as these may require complementary imaging modalities for comprehensive assessment. This abstract is funded by: None

Cover page of Social Determinants of Health and Pediatric Long COVID in the US

Social Determinants of Health and Pediatric Long COVID in the US

(2026)

Importance: Millions of children worldwide are experiencing prolonged symptoms after SARS-CoV-2 infection, yet social risk factors for developing long COVID are largely unknown. As child health is influenced by the environment in which they live and interact, adverse social determinants of health (SDOH) may contribute to the development of pediatric long COVID. Objective: To identify whether adverse SDOH are associated with increased odds of long COVID in school-aged children and adolescents in the US. Design, Setting, and Participants: This cross-sectional analysis of a multicenter, longitudinal, meta-cohort study encompassed 52 sites (health care and community settings) across the US. School-aged children (6-11 years; n = 903) and adolescents (12-17 years; n = 3681) with SARS-CoV-2 infection history were included. Those with an unknown date of first infection, history of multisystem inflammatory syndrome in children, or symptom surveys with less than 50% of questions completed were excluded. Participants were recruited via health care systems, long COVID clinics, fliers, websites, social media campaigns, radio, health fairs, community-based organizations, community health workers, and existing research cohorts from March 2022 to August 2024, and surveys were completed by caregivers between March 2022 and August 2024. Exposure: Twenty-four individual social determinant of health factors were grouped into 5 Healthy People 2030 domains: economic stability, social and community context, caregiver education access and quality, neighborhood and built environment, and health care access and quality. Latent classes were created within each domain and used in regression models. Main Outcomes and Measures: Presence of long COVID using caregiver-reported, symptom-based, age-specific research indices. Results: The mean (SD) age among 4584 individuals included in this study was 14 (3) years, and 2330 (51%) of participants were male. The number of latent classes varied by domain; the reference group was the class with the least adversity. In unadjusted analyses, most classes in each domain were associated with higher odds of long COVID. After adjusting for many factors, including age group, sex, timing of infection, referral source, and other social determinant of health domains, economic instability characterized by difficulty covering expenses, poverty, receipt of government assistance, and food insecurity were associated with an increased risk of having long COVID (class 2 adjusted odds ratio [aOR], 1.57; 95% CI, 1.18-2.09; class 4 aOR, 2.39; 95% CI, 1.73-3.30); economic instability without food insecurity (class 3) was not (aOR, 0.93; 95% CI, 0.70-1.23). Poorer social and community context (eg, high levels of discrimination and low social support) was also associated with long COVID (aOR, 2.17; 95% CI, 1.77-2.66). Sensitivity analyses stratified by age group and adjusted for race and ethnicity did not alter or attenuate these results. Conclusions and Relevance: In this study, economic instability that included food insecurity and poor social and community context were associated with greater odds of pediatric long COVID. Those with food security, despite experiencing other economic challenges, did not have greater odds of long COVID. Further study is needed to determine if addressing SDOH factors can decrease the rate of pediatric long COVID.

Cover page of Optimizing Screening of Hepatocellular Carcinoma with Computed Tomography and MR Imaging Emerging Research, Updated Guidelines, and New Technologies

Optimizing Screening of Hepatocellular Carcinoma with Computed Tomography and MR Imaging Emerging Research, Updated Guidelines, and New Technologies

(2026)

Ultrasound is the standard first-line imaging modality for hepatocellular carcinoma (HCC) screening; however, in certain patient populations, sensitivity is limited, and thus alternative strategies are needed in these patients. This article will provide an overview of MR imaging and computed tomography (CT) for the screening of HCC, with an emphasis on abbreviated MR imaging protocols and recent advancements in CT technology (dual energy and photon-counting CT).

Cover page of Bicomponent Mapping of Cortical Bone Using a New Interleaved UTE Imaging Sequence

Bicomponent Mapping of Cortical Bone Using a New Interleaved UTE Imaging Sequence

(2026)

PURPOSE: Ultrashort echo time (UTE) MRI enables direct imaging of cortical bone and quantification of its water compartments via bicomponent T2* modeling. However, conventional approaches require multiple separate dual-echo scans due to limitations in gradient power. This approach is prone to inter-scan inconsistencies such as motion and signal drift, which degrade fitting accuracy. This study proposes an interleaved dual-echo acquisition sequence that acquires multiple echo time (TE) images in a single scan to improve bicomponent T2* quantification in cortical bone. METHODS: The proposed UTE sequence utilizes interleaved dual-echo acquisitions with flexible TE spacings. This sequence was tested on five healthy subjects' tibial midshafts and compared to conventional separate dual-echo scans with and without image registration. Bicomponent T2* modeling was performed, and fitting accuracy was evaluated using normalized-root-mean-squared error (NRMSE). Three subjects were scanned three times to evaluate the scan repeatability. RESULTS: The interleaved method significantly reduced NRMSE (3.2% ± 2.3% vs. 6.2% ± 3.1%, p = 0.0231) and yielded lower and more stable T2* (T2s*; 0.50 ± 0.10 ms vs. 0.76 ± 0.13 ms, p < 0.0001) and fraction (Fs; 78.2 ± 5.1 vs. 84.2% ± 7.1%, p = 0.0006) of short T2 components compared to separate scans without registration. Image registration had a minimal improvement on mapping results for separate scans. Parameter maps from the interleaved scans confirmed more homogeneous distributions of T2s* and Fs with lower fitting errors. The much lower coefficients of variance of the interleaved scans demonstrated improved repeatability compared with separate scans. CONCLUSION: The proposed interleaved UTE dual-echo sequence improves the robustness of bicomponent T2* mapping of the cortical bone by reducing inter-scan inconsistencies.

A Non-Invasive Gas Exchange Monitor To Assess Swimming-Induced Pulmonary Edema.

(2026)

Introduction: Swimming-induced pulmonary edema (SIPE) occurs in physically demanding environments. SIPE has been identified among U.S. Naval Special Warfare (NSW) candidates, risking trainees' lives or, less severely, preventing them from completing training. Diagnosis is based on clinical examination and chest X-ray. The MediPines gas exchange monitor AGM-100 is a noninvasive diagnostic tool approved by the FDA and used in hospital settings. This study aimed to assess noninvasive physiological parameters and evaluate the use of the AGM-100 in NSW candidates with SIPE. Methods: In this observational study, eighteen subjects were tested (nine with confirmed SIPE). Data on a noninvasive surrogate for oxygen deficit, based on end-tidal oxygen (EtO₂),carbon dioxide (EtCO₂), and SpO₂ were collected. Chest X-rays (CXR) were graded for interstitial and airspace edema. Results: Subjects with confirmed SIPE displayed an oxygen deficit (28.1 ± 12.9 mm Hg), while eight of nine subjects without SIPE did not (3.1 ± 8.79 mm Hg, p < 0.001). There were no differences in EtCO₂. SpO₂ was lower in individuals with confirmed SIPE (95.1 ± 2.23%) compared to controls/unconfirmed SIPE (98.1 ± 0.31%, p-value < 0.0001). The group with the oxygen deficit had a correspondingly worse edema grade on CXR. Discussion: These limited results showed a possible correlation between O₂ deficit and SIPE, while the AGM-100 performed reliably in this prehospital setting. Future higher-powered studies are needed to substantiate these findings and the AGM-100's utility, possibly extending to other environments, such as combat field hospitals, for rapid diagnosis and severity assessment of pulmonary edema.

Cover page of The University of California San Diego Post-Treatment Glioblastoma (UCSD-PTGBM) annotated multimodal MRI Dataset

The University of California San Diego Post-Treatment Glioblastoma (UCSD-PTGBM) annotated multimodal MRI Dataset

(2026)

We present the University of California San Diego post-treatment glioblastoma (UCSD-PTGBM) annotated multimodal MRI dataset. The UCSD-PTGBM dataset includes 243 timepoints on 178 subjects with histopathologically-proven glioblastoma who were imaged with an advanced brain tumor protocol on 3 Tesla MRI scanners. Sequences include standard 3D imaging, as well as multishell diffusion (Restricted Spectrum Imaging, RSI) and perfusion imaging techniques (Arterial Spin Labelling, ASL and Dynamic Susceptibility Contrast, DSC), and neuroradiologist approved voxelwise tumor segmentations for both traditional segmentation masks and cellular tumor segmentations. The dataset also includes isocitrate dehydrogenase (IDH) mutation status and O6-methylguianine-DNA methyl-transferase (MGMT) promotor methylation status, as well as overall survival and progression free survival information for a subset of cases. We hope that researchers around the world will use these data to continue to improve analysis of post-operative MRI on glioblastoma patients, translate their findings into clinical practice and improve the management and outcome for these patients.