Department of Radiology - Open Access Policy Deposits

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.]

Cover page of Discrimination Between Benign and Malignant Lesions With Restriction Spectrum Imaging MRI in an Enriched Breast Cancer Screening Cohort

Discrimination Between Benign and Malignant Lesions With Restriction Spectrum Imaging MRI in an Enriched Breast Cancer Screening Cohort

(2025)

Background

Breast cancer screening with dynamic contrast-enhanced MRI (DCE-MRI) is recommended for high-risk women but has limitations, including variable specificity and difficulty in distinguishing cancerous (CL) and high-risk benign lesions (HRBL) from average-risk benign lesions (ARBL). Complementary non-invasive imaging techniques would be useful to improve specificity.

Purpose

To evaluate the performance of a previously-developed breast-specific diffusion-weighted MRI (DW-MRI) model (BS-RSI3C) to improve discrimination between CL, HRBL, and ARBL in an enriched screening population.

Study type

Prospective.

Subjects

Exactly 187 women, either with mammography screening recommending additional imaging (N = 49) or high-risk individuals undergoing routine breast MRI (N = 138), before the biopsy.

Field strength/sequence

Multishell DW-MRI echo planar imaging sequence with a reduced field of view at 3.0 T.

Assessment

A total of 72 women had at least one biopsied lesion, with 89 lesions categorized into ARBL, HRBL, CL, and combined CLs and HRBLs (CHRLs). DW-MRI data were processed to produce apparent diffusion coefficient (ADC) maps, and estimate signal contributions (C₁, C₂, and C₃-restricted, hindered, and free diffusion, respectively) from the BS-RSI3C model. Lesion regions of interest (ROIs) were delineated on DW images based on suspicious DCE-MRI findings by two radiologists; control ROIs were drawn in the contralateral breast.

Statistical tests

One-way ANOVA and two-sided t-tests were used to assess differences in signal contributions and ADC values among groups. P-values were adjusted using the Bonferroni method for multiple testing, P = 0.05 was used for the significance level. Receiver operating characteristics (ROC) curves and intra-class correlations (ICC) were also evaluated.

Results

C₁, √C₁C₂, and logC1C2C3 were significantly different in HRBLs compared with ARBLs (P-values < 0.05). The logC1C2C3 had the highest AUC (0.821) in differentiating CHRLs from ARBLs, performing better than ADC (0.696), especially in non-mass enhancement (0.776 vs. 0.517).

Data conclusion

This study demonstrated the BS-RSI3C could differentiate HRBLs from ARBLs in a screening population, and separate CHRLs from ARBLs better than ADC.

Level of evidence: 1

Technical efficacy stage

2.

Cover page of Neurovascular crossing patterns between leash of Henry and deep branch of radial nerve: implications for neurointervention and diagnostic imaging.

Neurovascular crossing patterns between leash of Henry and deep branch of radial nerve: implications for neurointervention and diagnostic imaging.

(2025)

OBJECTIVE: To detail the neurovascular crossing patterns between the leash of Henry (LoH) and the deep branch of the radial nerve (DBRN) in supination and pronation of the forearm, using imaging methods with anatomic correlation. MATERIALS AND METHODS: This cross-sectional study was performed ex vivo with HRUS and MRI with anatomic correlation on 6 samples and in vivo with HRUS with Doppler on 55 participants scanned bilaterally. The in vivo participants were enrolled over a 6-month period. The crossing patterns between the LoH and DBRN were assessed ex vivo and in vivo. Additional morphological features of the DBRN, LoH, and fat plane were assessed in vivo only. Biometric features of the participants were recorded. Statistical analyses were performed using Shapiro-Wilk, parametric and non-parametric tests. RESULTS: The most common neurovascular crossing pattern was the ascending branch of the radial recurrent artery (RRAab) crossing below (ex vivo: 83.3%, in vivo: 85.3%) and the muscular branch crossing above (ex vivo: 100%, in vivo: 63.2% %) the DBRN. Both the deep and superficial surfaces of the DBRN exhibited an intimate relationship with the vessels of the LoH. A positive correlation between vessel diameter and anthropometric factors was observed. In addition, the muscular branch exhibited a significantly smaller diameter than the RRAab. CONCLUSION: Our study detailed the relationship between the LoH and the DBRN and highlighted the high incidence of vessel crossing above the DBRN at the level of the muscular branch. Knowledge of neurovascular crossings is crucial for understanding neurovascular entrapment syndromes and planning interventional procedures to reduce vascular complications.

Cover page of Estimation of Trabecular Bone Volume with Dual-Echo Ultrashort Echo Time (UTE) Magnetic Resonance Imaging (MRI) Significantly Correlates with High-Resolution Computed Tomography (CT).

Estimation of Trabecular Bone Volume with Dual-Echo Ultrashort Echo Time (UTE) Magnetic Resonance Imaging (MRI) Significantly Correlates with High-Resolution Computed Tomography (CT).

(2025)

Trabecular bone architecture has important implications for the mechanical strength of bone. Trabecular elements appear as signal void when imaged utilizing conventional magnetic resonance imaging (MRI) sequences. Ultrashort echo time (UTE) MRI can acquire high signal from trabecular bone, allowing for quantitative evaluation. However, the trabecular morphology is often disturbed in UTE-MRI due to chemical shift artifacts caused by the presence of fat in marrow. This study aimed to evaluate a UTE-MRI technique to estimate the trabecular bone volume fraction (BVTV) without requiring trabecular-level morphological assessment. A total of six cadaveric distal tibial diaphyseal trabecular bone cubes were scanned using a dual-echo UTE Cones sequence (TE = 0.03 and 2.2 ms) on a clinical 3T MRI scanner and on a micro-computed tomography (μCT) scanner. The BVTV was calculated from 10 consecutive slices on both the MR and μCT images. BVTV calculated from the MR images showed strongly significant correlation with the BVTV determined from μCT images (R = 0.84, p < 0.01), suggesting that UTE-MRI is a feasible technique for the assessment of trabecular bone microarchitecture. This would allow for the non-invasive assessment of information regarding bone strength, and UTE-MRI may potentially serve as a novel tool for assessment of fracture risk.

Cover page of Non-invasive evaluation of Achilles tendon and its enthesis using ultrashort echo time adiabatic T1ρ (UTE-Adiab-T1ρ) magnetic resonance imaging (MRI) in psoriatic arthritis

Non-invasive evaluation of Achilles tendon and its enthesis using ultrashort echo time adiabatic T1ρ (UTE-Adiab-T1ρ) magnetic resonance imaging (MRI) in psoriatic arthritis

(2025)

Purpose

This cross-sectional study investigates the utility of the quantitative ultrashort echo time (UTE) adiabatic T_1ρ (UTE-Adiab-T_1ρ) magnetic resonance imaging (MRI) in detecting potential differences in Achilles tendons and entheses of patients with psoriatic arthritis disease (PsA) compared with asymptomatic volunteers.

Material and method

The Achilles tendons of forty-four PsA patients (59 ± 15 years old, 38 % female) and thirty-seven asymptomatic volunteers (32 ± 10 years old, 51 % female) were scanned on a 3 T clinical scanner in the sagittal plane using a 3-inch surface coil. The 3D UTE-Adiab-T_1ρ sequences with fat saturation (FS) were used to measure UTE-Adiab-T_1ρ. Tenderness of the tendons, the SF-12 health survey, and visual analog scale (VAS) were recorded for the patients. The Kruskal Wallis test was used to examine the differences in UTE-Adiab-T1_ρ values between asymptomatic volunteers and patients, as well as subgroups of patients with pain in the Achilles tendon region and those treated with Biologics. Spearman's correlation coefficients were calculated between UTE-Adiab-T_1ρ and patient evaluations. P values < 0.05 were considered significant.

Results

UTE-Adiab-T_1ρ was significantly higher for the PsA group compared with the asymptomatic group in the enthesis (11.4 ± 2.6 ms vs. 10.4 ± 2.4 ms) and tensile tendon regions (9.8 ± 2.8 ms vs. 7.7 ± 1.7 ms). PsA patients with active Achilles pain showed significantly lower T1ρ in the entheses compared with other patients (10.7 ± 2.6 ms vs. 11.7 ± 2.5 ms). PsA patients treated with Biologics showed significantly lower T_1ρ values in the tendon compared with other patients (9.5 ± 2.5 ms vs. 10.3 ± 3.3 ms). The VAS score of patients showed a significant negative but weak correlation (R = -0.2) with UTE-Adiab-T1ρ of the enthesis. Correlations with SF-12 scores were not significant.

Conclusion

This study highlighted the UTE-Adiab-T_1ρ sequence capability in evaluating tendons and entheses and their potential involvement in PsA disease or response to therapies.

Cover page of Ethnic and racial differences in children and young people with respiratory and neurological post-acute sequelae of SARS-CoV-2: an electronic health record-based cohort study from the RECOVER Initiative

Ethnic and racial differences in children and young people with respiratory and neurological post-acute sequelae of SARS-CoV-2: an electronic health record-based cohort study from the RECOVER Initiative

(2025)

Background

Children from racial and ethnic minority groups are at greater risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, but it is unclear whether they have increased risk for post-acute sequelae of SARS-CoV-2 (PASC). Our objectives were to assess whether the risk of respiratory and neurologic PASC differs by race/ethnicity and social drivers of health.

Methods

We conducted a retrospective cohort study of individuals <21 years seeking care at 24 health systems across the U.S, using electronic health record (EHR) data. Our cohort included those with a positive SARS-CoV-2 molecular, serology or antigen test, or with a COVID-19, multisystem inflammatory disease in children, or PASC diagnosis from February 29, 2020 to August 1, 2022. We identified children/youth with at least 2 codes associated with respiratory and neurologic PASC. We measured associations between sociodemographic and clinical characteristics and respiratory and neurologic PASC using odds ratios and 95% confidence intervals estimated from multivariable logistic regression models adjusted for other sociodemographic characteristics, social vulnerability index or area deprivation index, time period of cohort entry, presence and complexity of chronic respiratory (respectively, neurologic) condition and healthcare utilization.

Findings

Among 771,725 children in the cohort, 203,365 (26.3%) had SARS-CoV-2 infection. Among children with documented infection, 3217 children had respiratory PASC and 2009 children/youth had neurologic PASC. In logistic regression models, children <5 years (Odds Ratio [OR] 1.78, 95% CI 1.62-1.97), and of Hispanic White descent (OR 1.19, 95% CI 1.05-1.35) had higher odds of having respiratory PASC. Children/youth living in regions with higher area deprivation indices (OR 1.25, 95% CI 1.10-1.420 for 60-79th percentile) and with chronic complex respiratory conditions (OR 3.28, 95% CI 2.91-3.70) also had higher odds of respiratory PASC. In contrast, older (OR 1.57, 95% CI 1.40-1.77 for those aged 12-17 years), non-Hispanic White individuals and those with chronic pre-existing neurologic conditions (OR 2.04, 95% CI 1.78-2.35) were more likely to have a neurologic PASC diagnosis.

Interpretation

Racial and ethnic differences in healthcare utilization for neurologic and respiratory PASC may reflect social drivers of health and inequities in access to care.

Funding

National Institutes of Health.

Cover page of Evaluation of the Femoral Condyle Radius of Curvature at the Chondral Surface Shows Significant Correlation With the Anterior-Posterior Length.

Evaluation of the Femoral Condyle Radius of Curvature at the Chondral Surface Shows Significant Correlation With the Anterior-Posterior Length.

(2025)

BACKGROUND: Accurate donor-recipient matching of the femoral condyle radius of curvature (ROC) in osteochondral allograft (OCA) transplantation may aid in minimizing articular surface incongruities. Matching linear femorotibial dimensions, such as the femoral condyle anterior-posterior length (APL), femoral condyle width (lateral-medial length, LML), femoral hemicondyle width (HCW), and tibial plateau width (TPW), can provide similar results if they correlate well with ROC. This study investigates the relationship between femorotibial dimensions and ROC at the cartilage surface using magnetic resonance imaging (MRI). METHODS: Deidentified MRI images of 63 patients (35 men, 33 ± 10 years old, and 28 women, 27 ± 8 years old) were analyzed. Axial images were used for APL, LML, and TPW (TPW-Ax) measurements, while coronal images were used for HCW and TPW (TPW-Cor) measurements. Cartilage was segmented in true sagittal images at the medial femoral condyle (MFC) and lateral femoral condyle (LFC) to calculate their specific cartilage surface ROCs. Linear regression models were used to determine the relationship between the femorotibial dimensions and ROC. RESULTS: Cartilage ROC was significantly correlated with all the linear femorotibial dimensions at the MFC (P < 0.01, R2 = 0.78, 0.69, 0.67, 0.59, and 0.37 for ROC correlations with APL, LML, TPW-Ax, TPW-Cor, and HCW, respectively), and the LFC (P < 0.01, R2 = 0.81, 0.61, 0.56, 0.54, and 0.41 for ROC correlations with APL, LML, TPW-Ax, TPW-Cor, and HCW, respectively). CONCLUSIONS: The APL was the most predictive femorotibial dimension of the cartilage surface ROC. Donor-recipient APL matching in OCA transplantation may provide a similar level of matching to that achievable by direct ROC measurements. The APL matching may help reduce cartilage incongruities, particularly for patients with large osteochondral lesions, in which the ROC measurement cannot be accurately determined.

Association of LR treatment response category with outcome of patients with hepatocellular carcinoma on explant pathology

(2025)

Objectives

Liver transplant (LT) is an effective treatment for hepatocellular carcinoma (HCC) in appropriately selected patients. Locoregional therapy (LRT) is often performed to extend a patient's eligibility for LT. Imaging has a modest sensitivity of approximately 40-77% for detecting pathologically viable HCC in post-LRT patients. The impact on overall survival (OS) and disease-free survival (DFS) is unclear. We hypothesize that Liver Imaging Reporting & Data Systems Treatment Response (LI-RADS TR) category is equivalently correlated with long-term survival and overall disease-free progression when compared to explant pathology findings. We additionally hypothesize that neoadjuvant LRT can improve OS and DFS in LT patients initially within MC.

Methods

Patients found to have HCC on explant between January 2005 and December 2021 were included. A total of 167 patients were divided into treatment (any pre-LT LRT except for Y-90 therapy) and control (no pre-LT LRT) groups. Of the patients who received pre-LT LRT, imaging studies were reviewed by two abdominal radiologists using 2018 LI-RADS criteria. Statistical analysis was performed using Kaplan-Meier survival curves and Cox proportional hazard models to assess OS and DFS.

Results

No statistically significant difference in OS or DFS (p = 0.23 and p = 0.22 respectively) was initially found. Given significant difference in age between the groups (p < 0.0001), Cox proportional hazard models were used to adjust for age with statistical significance reached for better OS and DFS in the treatment group (p = 0.05 and p = 0.05 respectively). Contrary to our hypothesis, there was no difference between treatment response groups regarding overall survival or disease-free survival, presumably because of low number of HCC recurrences in our patient population (4%).

Conclusion

Despite not reaching statistical significance, LI-RADS TR categorization demonstrates a good interreader agreement (Kappa 0.6), helping radiologists feel comfortable that modest sensitivity of the LI-RADS TR treatment response category for detecting pathologically active malignancy does not confer a negative clinical outcome.

Ultrashort Echo Time Magnetic Resonance Morphology of Discovertebral Junction in Chronic Low Back Pain Subjects.

(2025)

Background: Chronic low back pain (LBP) has been associated with intervertebral disc (IVD) degeneration, but its association with abnormal morphology at the discovertebral junction (DVJ) is unclear. The goal of this study was to evaluate the DVJ morphology in asymptomatic (Asx) and symptomatic (Sx) subjects for LBP using ultrashort echo time (UTE) MRI. Methods: We recruited 42 subjects (12 Asx and 32 Sx). Lumbar IVD degeneration was assessed using Pfirrmann grading (1 to 5), while the abnormality of DVJ (0 = normal; 1 = focal; 2 = broad abnormality) was assessed using UTE MRI. The effects of LBP and level on the mean IVD and DVJ grades, the correlation between IVD and DVJ grade, and the effect of LBP and age on the number of abnormal DVJs within a subject were determined. Results: IVD grade was higher in Sx subjects (p = 0.013), varying with disc level (p = 0.033), adjusted for age (p < 0.01). Similarly, DVJ grade was also significantly higher in Sx subjects (p = 0.001), but it did not vary with DVJ level (p = 0.7), adjusted for age (p = 0.5). There was a weak positive (rho = 0.344; p < 0.001) correlation between DVJ and IVD grade. The total number of abnormal DVJs within a subject was higher in Sx subjects (p < 0.001), but not with respect to age (p = 0.6) due to a large spread throughout the age range. Conclusions: These results demonstrate the feasibility of using in vivo UTE MRI of the lumbar spine to evaluate the DVJ and the correlation of DVJ with LBP. This study highlights the need for a better understanding of DVJ pathology and the inclusion of DVJ assessment in routine lumbar MRI.

School of Medicine