Posterior Subcutaneous Edema at Lumbar Spine MRI: A Systematic Review.

RATIONALE AND OBJECTIVES: Edema in the subcutaneous soft tissue of the lumbar spine is a frequent incidental finding in spinal magnetic resonance imaging, however, its exact explanation is yet to be determined. The aim of this paper is to provide a systematic literature review on posterior lumbar subcutaneous edema (LSE). MATERIALS AND METHODS: The present systematic literature search was carried out in October 2023 using electronic databases: PubMed, Cochrane library, and Scopus. RESULTS: The current evidence suggests that lumbar edema is correlated with clinical data such as weight and age, and potentially female sex. Moreover, LSE is related to several specific conditions, including both systemic and spinal disorders, such as heart or kidney disorders, as well as low back pain and degenerative and/or inflammatory diseases. CONCLUSION: It is important to be aware that there is an association between LSE and a variety systemic and spinal disorders.

Contrast media for hysterosalpingography: systematic search and review providing new guidelines by the Contrast Media Safety Committee of the European Society of Urogenital Radiology.

OBJECTIVES: Hysterosalpingography (HSG) is widely used for evaluating the fallopian tubes; however, controversies regarding the use of water- or oil-based iodine-based contrast media (CM) remain. The aim of this work was (1) to discuss reported pregnancy rates related to the CM type used, (2) to validate the used CM in published literature, (3) to discuss possible complications and side effects of CM in HSG, and (4) to develop guidelines on the use of oil-based CM in HSG. METHODS: A systematic literature search was conducted for original RCT studies or review/meta-analyses on using water-based and oil-based CM in HSG with fertility outcomes and complications. Nine randomized controlled trials (RCTs) and 10 reviews/meta-analyses were analyzed. Grading of the literature was performed based on the Oxford Centre for Evidence-Based Medicine (OCEBM) 2011 classification. RESULTS: An approximately 10% higher pregnancy rate is reported for oil-based CM. Side effects are rare, but oil-based CM have potentially more side effects on the maternal thyroid function and the peritoneum. CONCLUSIONS: 1. HSG with oil-based CM gives approximately 10% higher pregnancy rates. 2. External validity is limited, as in five of nine RCTs, the CM used is no longer on the market. 3. Oil-based CM have potentially more side effects on the maternal thyroid function and on the peritoneum. 4. Guideline: Maternal thyroid function should be tested before HSG with oil-based CM and monitored for 6 months after. CLINICAL RELEVANCE STATEMENT: Oil-based CM is associated with an approximately 10% higher chance of pregnancy compared to water-based CM after HSG. Although side effects are rare, higher iodine concentration and slower clearance of oil-based CM may induce maternal thyroid function disturbance and peritoneal inflammation and granuloma formation. KEY POINTS: • It is unknown which type of contrast medium, oil-based or water-based, is the optimal for HSG. • Oil-based contrast media give a 10% higher chance of pregnancy after HSG, compared to water-based contrast media. • From the safety perspective, oil-based CM can cause thyroid dysfunction and an intra-abdominal inflammatory response in the patient.

Ten years of gadolinium retention and deposition: ESMRMB-GREC looks backward and forward.

In 2014, for the first time, visible hyperintensities on unenhanced T1-weighted images in the nucleus dentatus and globus pallidus of the brain were associated with previous Gadolinium-based contrast agent (GBCA) injections and gadolinium deposition in patients with normal renal function. This led to a frenzy of retrospective studies with varying methodologies that the European Society of Magnetic Resonance in Medicine and Biology Gadolinium Research and Educational Committee (ESMRMB-GREC) summarised in 2019. Now, after 10 years, the members of the ESMRMB-GREC look backward and forward and review the current state of knowledge of gadolinium retention and deposition. CLINICAL RELEVANCE STATEMENT: Gadolinium deposition is associated with the use of linear GBCA but no clinical symptoms have been associated with gadolinium deposition. KEY POINTS : • Traces of Gadolinium-based contrast agent-derived gadolinium can be retained in multiple organs for a prolonged time. • Gadolinium deposition is associated with the use of linear Gadolinium-based contrast agents. • No clinical symptoms have been associated with gadolinium deposition.

Visceral adiposity in patients with lipomatous hypertrophy of the interatrial septum.

Lipomatous hypertrophy of the interatrial septum (LHIS) is a benign cardiac mass determined by abnormal deposition of adipose tissue in the interatrial septum. The quantitative relationship between LHIS and visceral adiposity has not been explored to date.In this retrospective study, three groups of consecutive patients undergoing CT imaging were enrolled: L + with LHIS, L- without LHIS, and LO- without both LHIS and history of malignancies. Areas of total adipose tissue (TAT), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and LHIS areas were calculated on CT images. The relationship between LHIS and abdominal fat distribution was investigated with linear regression models. Bonferroni correction was applied to account for multiple testing. Statistical significance was set at 5%. In this study we enrolled a total of 175 subjects: 58 (33.14%) with LHIS (L +), 51(29.14%) without LHIS (L-) and 66 (37.71%) without both LHIS and medical history of malignancies (LO-). VAT (coeff: 105.82; 95% CI 59.37-152.27), SAT (coeff: 74.59; 95% CI 31.63-117.54), and TAT (coeff: 190.37; 95% CI 115.02-265.72), were significantly higher in L + patients. Moreover, VAT (coeff: 24.95; 95% CI 6.94-42.96) and TAT (coeff: 36.58; 95% CI 8.75-64.41) were statistically significant linear predictors for LHIS area. Here, we report a novel association between LHIS and visceral adiposity using a quantitative CT-based imaging approach. The results are of great importance also because they might drive early identification of subjects with LHIS at risk for visceral obesity, and trigger lifestyle interventions aimed at weight loss.

Use of gadolinium-based contrast agents in multiple sclerosis: a review by the ESMRMB-GREC and ESNR Multiple Sclerosis Working Group.

Magnetic resonance imaging (MRI) is the most sensitive technique for detecting inflammatory demyelinating lesions in multiple sclerosis (MS) and plays a crucial role in diagnosis and monitoring treatment effectiveness, and for predicting the disease course. In clinical practice, detection of MS lesions is mainly based on T2-weighted and contrast-enhanced T1-weighted sequences. Contrast-enhancing lesions (CEL) on T1-weighted sequences are related to (sub)acute inflammation, while new or enlarging T2 lesions reflect the permanent footprint from a previous acute inflammatory demyelinating event. These two types of MRI features provide redundant information, at least in regular monitoring of the disease. Due to the concern of gadolinium deposition after repetitive injections of gadolinium-based contrast agents (GBCAs), scientific organizations and regulatory agencies in Europe and North America have proposed that these contrast agents should be administered only if clinically necessary. In this article, we provide data on the mode of action of GBCAs in MS, the indications of the use of these agents in clinical practice, their value in MS for diagnostic, prognostic, and monitoring purposes, and their use in specific populations (children, pregnant women, and breast-feeders). We discuss imaging strategies that achieve the highest sensitivity for detecting CELs in compliance with the safety regulations established by different regulatory agencies. Finally, we will briefly discuss some alternatives to the use of GBCA for detecting blood-brain barrier disruption in MS lesions. CLINICAL RELEVANCE STATEMENT: Although use of GBCA at diagnostic workup of suspected MS is highly valuable for diagnostic and prognostic purposes, their use in routine monitoring is not mandatory and must be reduced, as detection of disease activity can be based on the identification of new or enlarging lesions on T2-weighted images. KEY POINTS: • Both the EMA and the FDA state that the use of GBCA in medicine should be restricted to clinical scenarios in which the additional information offered by the contrast agent is required. • The use of GBCA is generally recommended in the diagnostic workup in subjects with suspected MS and is generally not necessary for routine monitoring in clinical practice. • Alternative MRI-based approaches for detecting acute focal inflammatory MS lesions are not yet ready to be used in clinical practice.

Analytical interference of intravascular contrast agents with clinical laboratory tests: a joint guideline by the ESUR Contrast Media Safety Committee and the Preanalytical Phase Working Group of the EFLM Science Committee.

The Contrast Media Safety Committee of the European Society of Urogenital Radiology has, together with the Preanalytical Phase Working Group of the EFLM Science Committee, reviewed the literature and updated its recommendations to increase awareness and provide insight into these interferences.

Waiting times between examinations with intravascularly administered contrast media: a review of contrast media pharmacokinetics and updated ESUR Contrast Media Safety Committee guidelines.

The pharmacokinetics of contrast media (CM) will determine how long safe waiting intervals between successive CT or MRI examinations should be. The Contrast Media Safety Committee has reviewed the data on pharmacokinetics of contrast media to suggest safe waiting intervals between successive contrast-enhanced imaging studies in relation to the renal function of the patient. CLINICAL RELEVANCE STATEMENT: Consider a waiting time between elective contrast-enhanced CT and (coronary) angiography with successive iodine-based contrast media administrations in patients with normal renal function (eGFR > 60 mL/min/1.73 m2) of optimally 12 h (near complete clearance of the previously administered iodine-based contrast media) and minimally 4 h (if clinical indication requires rapid follow-up). KEY POINTS: • Pharmacokinetics of contrast media will guide safe waiting times between successive administrations. • Safe waiting times increase with increasing renal insufficiency. • Iodine-based contrast media influence MRI signal intensities and gadolinium-based contrast agents influence CT attenuation.

Analytical interference of intravascular contrast agents with clinical laboratory tests: a joint guideline by the ESUR Contrast Media Safety Committee and the Preanalytical Phase Working Group of the EFLM Science Committee.

The Contrast Media Safety Committee of the European Society of Urogenital Radiology has, together with the Preanalytical Phase Working Group of the EFLM Science Committee, reviewed the literature and updated its recommendations to increase awareness and provide insight into these interferences. CLINICAL RELEVANCE STATEMENT: Contrast Media may interfere with clinical laboratory tests. Awareness of potential interference may prevent unwanted misdiagnosis. KEY POINTS: • Contrast Media may interfere with clinical laboratory tests; therefore awareness of potential interference may prevent unwanted misdiagnosis. • Clinical Laboratory tests should be performed prior to radiological imaging with contrast media or alternatively, blood or urine collection should be delayed, depending on kidney function.

Safe use of contrast media in myasthenia gravis: systematic review and updated European Society of Urogenital Radiology Contrast Media Safety Committee guidelines.

OBJECTIVES: It is uncertain whether modern iodine-based or gadolinium-based contrast media (CM) administration can lead to increased symptoms in patients with myasthenia gravis. METHODS: A systematic search in Medline was conducted for studies describing the symptomatology of myasthenia gravis patients before and after receiving intravenous (IV) CM and having a matched control group of myasthenia gravis patients who did not receive IV CM. RESULTS: Three retrospective studies were selected with a total of 374 myasthenia gravis patients who received iodine-based CM and a total of 313 myasthenia gravis patients who underwent unenhanced CT and served as controls. Pooling of the data from the three retrospective studies showed that in 23 of 374 patients, increased symptoms after iodine-based CM administration were described (6.1%). Increased symptomatology also occurred in 11 of 313 patients after unenhanced CT (3.5%). When looking more deeply into the data of the three studies, conflicting results were found, as two articles did not find any relationship between CM and myasthenia gravis symptoms. The remaining study only found a significant increase in symptomatology within 1 day after CT scanning: seven patients (6.3%) in the contrast-enhanced CT group and one patient (0.6%) in the unenhanced CT group (p = 0.01). CONCLUSIONS: There is limited evidence on the relationship between CM and myasthenia gravis symptoms. In the vast majority of myasthenia gravis patients, CM are safe. Probably, in less than 5% of the patients, iodine-based CM administration may lead to increased severity of the symptoms within the first 24 h after administration. CLINICAL RELEVANCE STATEMENT: Be aware that intravenous administration of iodine-based contrast media can lead to an increase of symptoms in patients with myasthenia gravis within the first 24 h. This can probably happen in less than 5% of the patients. KEY POINTS: • It is unclear whether modern contrast media can lead to increased symptoms in myasthenia gravis patients after intravenous administration. • There seems to be a small risk of increased myasthenia gravis symptoms within 24 h after intravenous administration of iodine-based contrast media, probably in less than 5% of the administrations. • Gadolinium-based contrast media are safe for patients with myasthenia gravis.

Neuroradiology of acute pathologies in adults with hematologic malignancies: a pictorial review.

Hematopoietic and lymphoid tumors are a heterogeneous group of diseases including lymphomas, multiple myeloma (MM), and leukemias. These diseases are associated with systemic involvement and various clinical presentations including acute neurological deficits. Adult patients with hematologic malignancies (HM) are at risk for developing a wide array of acute conditions involving the nervous system. HM in adults may present as tumoral masses responsible for mass effect, possibly resulting in acute neurological signs and symptoms caused by tumor growth with compression of central nervous system (CNS) structures. Moreover, as result of the hematologic disease itself or due to systemic treatments, hematologic patients are at risk for vascular pathologies, such as ischemic, thrombotic, and hemorrhagic disorders due to the abnormal coagulation status. The onset of these disorders is often with acute neurologic signs or symptoms. Lastly, it is well known that patients with HM can have impaired function of the immune system. Thus, CNS involvement due to immune-related diseases such as mycotic, parasitic, bacterial, and viral infections linked to immunodeficiency, together with immune reconstitution inflammatory syndrome, are frequently seen in hematologic patients. Knowledge of the etiology and expected CNS imaging findings in patients with HM is of great importance to reach a fast and correct diagnosis and guide treatment choices. In this manuscript, we review the computed tomography (CT) and magnetic resonance findings of these conditions which can be related to the disease itself and/or to their treatments.

Innovative quantitative magnetic resonance tools to detect early intervertebral disc degeneration changes: a systematic review.

BACKGROUND CONTEXT: Low back pain (LBP) is the leading cause of disability worldwide, with a tremendous socioeconomic burden. It is mainly caused by intervertebral disc degeneration (IDD), a progressive and age-related process. Due to its ability to accurately characterize intervertebral disc morphology, magnetic resonance imaging (MRI) has been established as one of the most valuable tools in diagnosing IDD. Innovative quantitative MRI (qMRI) techniques able to detect the earliest signs of IDD have been increasingly reported. PURPOSE: To systematically review available reports on the application of novel qMRI techniques to detect early IDD changes. STUDY DESIGN: Systematic literature review. METHODS: A systematic search of PubMed/MEDLINE, Scopus, CINAHL, EMBASE, CENTRAL and Cochrane databases was performed through January 21, 2023. Randomized and nonrandomized studies on innovative qMRI tools able to diagnose early biochemical and architectural IDD changes in patients with or without discogenic LBP were searched. Data on study population, follow-up time (when applicable) and MRI sequence used were recorded. The QUADAS-2 tool was utilized to assess the risk of bias of included studies. RESULTS: A total of 39 articles published between 2005 and 2022 resulted from the search. All novel qMRI techniques showed an increased capacity to detect early IDD changes thanks to the ability to assess subtle alterations of water content, proteoglycan and glycosaminoglycan concentration, and increased levels of catabolic biomarkers compared to conventional MRI. CONCLUSIONS: Innovative qMRI techniques have proven effective in identifying premature IDD changes. Further studies are needed to validate their application in wider populations and confirm their applicability in the clinical setting.

Skin Toxicity After Exposure to Gadolinium-Based Contrast Agents in Normal Renal Function, Using Clinical Approved Doses: Current Status of Preclinical and Clinical Studies.

OBJECTIVES: The aim of this study was to summarize the current preclinical and clinical evidence on the association between exposure to gadolinium (Gd) compounds and skin toxicity in a setting similar to clinical practice. MATERIALS AND METHODS: A search of MEDLINE and PubMed references from January 2000 to December 2022 was performed using keywords related to gadolinium deposition and its effects on the skin, such as "gadolinium," "gadolinium-based contrast agents," "skin," "deposition," and "toxicity." In addition, cross-referencing was added when appropriate. For preclinical in vitro studies, we included all the studies that analyzed the response of human dermal fibroblasts to exposure to various gadolinium compounds. For preclinical animal studies and clinical studies, we included only those that analyzed animals or patients with preserved renal function (estimated glomerular filtration rate >30 mL/min/1.73 m 2 ), using a dosage of gadolinium-based contrast agents (GBCAs) similar to that commonly applied (0.1 mmol/kg). RESULTS: Forty studies were selected. Preclinical findings suggest that Gd compounds can produce profibrotic responses in the skin in vitro, through the activation and proliferation of dermal fibroblasts and promoting their myofibroblast differentiation. Gadolinium influences the process of collagen production and the collagen content of skin, by increasing the levels of matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1. Preclinical animal studies show that Gd can deposit in the skin with higher concentrations when linear GBCAs are applied. However, these deposits decrease over time and are not associated with obvious macroscopic or histological modifications. The clinical relevance of GBCAs in inducing small fiber neuropathy remains to be determined. Clinical studies show that Gd is detectable in the skin and hair of subjects with normal renal function in higher concentrations after intravenous administration of linear compared with macrocyclic GBCA. However, these deposits decrease over time and are not associated with cutaneous or histological modifications. Also, subclinical dermal involvement related to linear GBCA exposure may be detectable on brain MRI. There is no conclusive evidence to support a causal relationship between GBCA administration at the clinical dose and cutaneous manifestations in patients with normal renal function. CONCLUSIONS: Gadolinium can produce profibrotic responses in the skin, especially acting on fibroblasts, as shown by preclinical in vitro studies. Gadolinium deposits are detectable in the skin even in subjects with normal renal function with higher concentrations when linear GBCAs are used, as confirmed by both preclinical animal and human studies. There is no proof to date of a cause-effect relationship between GBCA administration at clinical doses and cutaneous consequences in patients with normal renal function. Multiple factors, yet to be determined, should be considered for sporadic patients with normal renal function who develop clinical skin manifestations temporally related to GBCA administration.

Artificial Intelligence to Reduce or Eliminate the Need for Gadolinium-Based Contrast Agents in Brain and Cardiac MRI: A Literature Review.

ABSTRACT: Brain and cardiac MRIs are fundamental noninvasive imaging tools, which can provide important clinical information and can be performed without or with gadolinium-based contrast agents (GBCAs), depending on the clinical indication. It is currently a topic of debate whether it would be feasible to extract information such as standard gadolinium-enhanced MRI while injecting either less or no GBCAs. Artificial intelligence (AI) is a great source of innovation in medical imaging and has been explored as a method to synthesize virtual contrast MR images, potentially yielding similar diagnostic performance without the need to administer GBCAs. If possible, there would be significant benefits, including reduction of costs, acquisition time, and environmental impact with respect to conventional contrast-enhanced MRI examinations. Given its promise, we believe additional research is needed to increase the evidence to make these AI solutions feasible, reliable, and robust enough to be integrated into the clinical framework. Here, we review recent AI studies aimed at reducing or replacing gadolinium in brain and cardiac imaging while maintaining diagnostic image quality.

Computed tomography density changes of bone metastases after concomitant denosumab.

OBJECTIVE: To evaluate bone density changes at the level of normal trabecular bone and bone metastases (BMs) after denosumab (DM) treatment in oncologic patients. MATERIALS AND METHODS: We retrospectively evaluated 31 consecutive adult patients with histologically confirmed solid tumors with at least one newly diagnosed bone metastatic lesion detected at CT. Patients received treatment with DM, 120 mg subcutaneous every 28 days for at least 6 months. Bone density was determined at the level of BMs and at the level of normal trabecular bone of lumbar vertebrae using a region of interest (ROI)-based approach. RESULTS: A progressive increase in CT bone density was demonstrated at the level of normal trabecular bone at 6 months (18% ± 5%) and 12 months (23% ± 7%) after the treatment begins. BMs showed a significant increase in CT bone density (p < 0.05) as compared to baseline after 6 months (57% ± 15%) and 12 months (1.06 ± 0.25 times higher) after treatment. CONCLUSION: We have found that long-term treatment with DM increases bone density progressively in oncologic patients. This effect can be observed not only at the level of secondary lesions but also at the level of apparently normal trabecular bone and is more pronounced for osteolytic metastases.

Skin Thickening of the Scalp and High Signal Intensity of Dentate Nucleus in Multiple Sclerosis: Association With Linear Versus Macrocyclic Gadolinium-Based Contrast Agents Administration.

OBJECTIVE: The aim of this study was to assess the presence of detectable changes of skin thickness on clinical brain magnetic resonance imaging (MRI) scans in patients with MS, history of multiple gadolinium-based contrast agents (GBCAs) administrations, and evidence of gadolinium deposition in the brain. MATERIALS AND METHODS: In this observational cross-sectional study, 71 patients with MS who underwent conventional brain MRI with an imaging protocol including enhanced 3D volumetric interpolated breath-hold examination (VIBE) T1-weighted with fat saturation were assessed. Patients with bilateral isointense dentate nucleus on unenhanced T1-weighted images were assigned to group A (controls without MRI evidence of gadolinium deposition), and patients with visually hyperintense dentate nuclei were assigned to group B. Qualitative and quantitative assessment of the skin thickness were performed. RESULTS: Group A included 27 patients (median age, 33 years [IQR, 27-46]; 20 women), and group B included 44 patients (median age, 42 years [IQR, 35-53]; 29 women). Qualitative and quantitative assessment of the skin revealed significant differences between group A and group B. The average skin-to-scalp thickness ratios was significantly higher in group B than in group A (mean ± standard deviation = 0.52 ± 0.02 in group B vs 0.41 ± 0.02 in group A, P < 0.0001) and showed a positive correlation with the total number of enhanced MRI scans ( r = 0.39; 95% confidence interval, 0.17-0.57, P < 0.01). CONCLUSIONS: Brain MRI detects increased skin thickness of the scalp in patients with MS and dentate nucleus high signal intensity on unenhanced T1-weighted images and shows positive association with previous exposures to linear GBCAs rather than macrocyclic GBCAs.

Brain functional connectivity differences between responders and non-responders to sleeve gastrectomy.

PURPOSE: To compare resting-state functional connectivity (RSFC) of obese patients responders or non-responders to sleeve gastrectomy (SG) with a group of obese patients with no past medical history of metabolic or bariatric surgery. METHODS: MR images were acquired at 1.5 Tesla. Resting-state fMRI data were analyzed with statistical significance threshold set at p < 0.05, family-wise error (FWE) corrected. RESULTS: Sixty-two subjects were enrolled: 20 controls (age range 25-64; 14 females), 24 responders (excess weight loss > 50%; age range 23-68; 17 females), and 18 non-responders to sleeve gastrectomy (SG) (excess weight loss < 50%; age range 23-67; 13 females). About within-network RSFC, responders showed significantly lower RSFC with respect to both controls and non-responders in the default mode and frontoparietal networks, positively correlating with psychological scores. Non-responders showed significantly higher (p < 0.05, family-wise error (few) corrected) RSFC in regions of the lateral visual network as compared to controls. Regarding between-network RSFC, responders showed significantly higher anti-correlation between executive control and salience networks (p < 0.05, FWE corrected) with respect to both controls and non-responders. Significant positive correlation (Spearman rho = 0.48, p = 0.0012) was found between % of excess weight loss and executive control-salience network RSFC. CONCLUSION: There are differences in brain functional connectivity in either responders or non-responders patients to SG. The present results offer new insights into the neural correlates of outcome in patients who undergo SG and expand knowledge about neural mechanisms which may be related to surgical response.

A Rare Case of Contained Chronic Rupture of Abdominal Aortic Aneurysm Associated With Vertebral Erosion: Pre- and Post-operative Findings on Computed Tomography and a Narrative Review.

Contained chronic rupture of aortic aneurysm (CCR-AA) is a rare condition that can be associated with vertebral body erosion (VBE) and is often a diagnostic challenge; in fact, CCR-AAs are in general hemodynamically stable and the patients tend to present with a non-specific low-back pain syndrome secondary to vertebral involvement. Furthermore, the differential diagnosis of a retroperitoneal mass can be difficult on medical imaging. We discuss the case of a 79-years-old man, heavy smoker without history of cardiovascular diseases, admitted to the emergency department with signs of left lower limb ischemia. The patient was hemodynamically stable and the medical examination revealed a pulsatile abdominal mass. Doppler ultrasound showed the presence of aneurysmal dilatation of infra-renal abdominal aorta and chronic femoropopliteal occlusion on the left side. The subsequent computed tomography angiography (CTA) demonstrated a voluminous retroperitoneal mass continuous with the infra-renal aorta, which infiltrated the psoas muscles and caused vertebral bodies erosion of the anterior wall in L2, L3 and L4 suspected for CCR-AA or mycotic aortic aneurysm. Furthermore, the examination confirmed the occlusion of the peripheral arterial circulation of the left lower limb. The patient underwent a successful open replacement of the infra-renal abdominal aorta through aorto-aortic prosthetic graft insertion; the visualization during the surgical procedure of a posterior vessel wall opening in continuity with the eroded vertebral bodies associated with negative microbiological culture of the thrombotic material sample, led to the definitive diagnosis of CCR-AA. The post-operative CTA showed successful open vascular treatment. A bypass surgery of the left lower limb was then performed with positioning saphenous graft between femoral common artery and posterior tibial artery. The patient was finally discharged in good clinical conditions.

Facilitating standardized COVID-19 suspicion prediction based on computed tomography radiomics in a multi-demographic setting.

OBJECTIVE: To develop an automatic COVID-19 Reporting and Data System (CO-RADS)-based classification in a multi-demographic setting. METHODS: This multi-institutional review boards-approved retrospective study included 2720 chest CT scans (mean age, 58 years [range 18-100 years]) from Italian and Russian patients. Three board-certified radiologists from three countries assessed randomly selected subcohorts from each population and provided CO-RADS-based annotations. CT radiomic features were extracted from the selected subcohorts after preprocessing steps like lung lobe segmentation and automatic noise reduction. We compared three machine learning models, logistic regression (LR), multilayer perceptron (MLP), and random forest (RF) for the automated CO-RADS classification. Model evaluation was carried out in two scenarios, first, training on a mixed multi-demographic subcohort and testing on an independent hold-out dataset. In the second scenario, training was done on a single demography and externally validated on the other demography. RESULTS: The overall inter-observer agreement for the CO-RADS scoring between the radiologists was substantial (k = 0.80). Irrespective of the type of validation test scenario, suspected COVID-19 CT scans were identified with an accuracy of 84%. SHapley Additive exPlanations (SHAP) interpretation showed that the "wavelet_(LH)_GLCM_Imc1" feature had a positive impact on COVID prediction both with and without noise reduction. The application of noise reduction improved the overall performance between the classifiers for all types. CONCLUSION: Using an automated model based on the COVID-19 Reporting and Data System (CO-RADS), we achieved clinically acceptable performance in a multi-demographic setting. This approach can serve as a standardized tool for automated COVID-19 assessment. KEYPOINTS: • Automatic CO-RADS scoring of large-scale multi-demographic chest CTs with mean AUC of 0.93 ± 0.04. • Validation procedure resembles TRIPOD 2b and 3 categories, enhancing the quality of experimental design to test the cross-dataset domain shift between institutions aiding clinical integration. • Identification of COVID-19 pneumonia in the presence of community-acquired pneumonia and other comorbidities with an AUC of 0.92.