Utility of Dual-Energy Computed Tomography in Clinical Conundra.

Advancing medical technology revolutionizes our ability to diagnose various disease processes. Conventional Single-Energy Computed Tomography (SECT) has multiple inherent limitations for providing definite diagnoses in certain clinical contexts. Dual-Energy Computed Tomography (DECT) has been in use since 2006 and has constantly evolved providing various applications to assist radiologists in reaching certain diagnoses SECT is rather unable to identify. DECT may also complement the role of SECT by supporting radiologists to confidently make diagnoses in certain clinically challenging scenarios. In this review article, we briefly describe the principles of X-ray attenuation. We detail principles for DECT and describe multiple systems associated with this technology. We describe various DECT techniques and algorithms including virtual monoenergetic imaging (VMI), virtual non-contrast (VNC) imaging, Iodine quantification techniques including Iodine overlay map (IOM), and two- and three-material decomposition algorithms that can be utilized to demonstrate a multitude of pathologies. Lastly, we provide our readers commentary on examples pertaining to the practical implementation of DECT's diverse techniques in the Gastrointestinal, Genitourinary, Biliary, Musculoskeletal, and Neuroradiology systems.

A trend, analysis, and solution on women's representation in diagnostic radiology in North America: a narrative review.

Despite the demonstrated benefits of gender diversity in medicine, women in Radiology in North America are still underrepresented. We reviewed the literature to highlight the current status of women in Radiology in North America, identify the underlying causes of the gender gap, and provide potential strategies to close this gap. We conducted a narrative literature review using the terms ("Gender Disparity" OR "Gender Inequality") AND ("Radiology Department" OR "Radiology Residency"), searching data from April 2000 to April 2022 in Ovid Medline, Embase, PubMed, and Scopus. Our results indicate that Radiology in North America lacks gender diversity in its subspecialties, academic leadership, and research productivity, which the COVID-19 pandemic has further exacerbated. Challenges stemming from a dearth of women role models, limited preclinical contact, and a high rate of burnout contribute to the current gender inequality. Several complementary and supplementary steps can enhance gender diversity in Radiology. These include increasing education and exposure to Radiology at earlier stages and optimizing mentorship opportunities to attract a more diverse pool of talent to the discipline. In addition, supporting resident parents and enhancing the residency program's culture can decrease the rate of burnout and encourage women to pursue careers and leadership positions in Radiology.

The Role of Dual-Energy CT in Solid Organ Injury.

The liver, spleen, and kidneys are the commonest injured solid organs in blunt and penetrating trauma. The American Association for the Surgery of Trauma (AAST) Organ Injury Scale (OIS) is the most widely accepted system for categorizing traumatic injuries. Grading systems allow clear communication of findings between clinical teams and assign a measurable severity of injury, which directly correlates with morbidity and mortality. The 2018 revised AAST OIS emphasizes reliance on CT for accurate grading; in particular regarding vascular injuries. Dual-Energy CT (DECT) has emerged as a promising tool with multiple clinical applications already demonstrated. In this review article, we summarize the basic principles of CT attenuation to refresh the minds of our readers and we scrutinize DECT's technology as opposed to conventional Single-Energy CT (SECT). This is followed by outlining the benefits of various DECT postprocessing techniques, which authors of this article refer to as the 3Ms (Mapping of Iodine, Material decomposition, and Monoenergetic virtual imaging), in aiding radiologists to confidently assign an OIS as well as problem solve complex injury patterns. In addition, a thorough discussion of changes to the revised AAST OIS focusing on definitions of key terms used in reporting injuries is described.

Multidetector CT Imaging Biomarkers as Predictors of Prognosis in Shock: Updates and Future Directions.

A severe mismatch between the supply and demand of oxygen is the common sequela of all types of shock, which present a mortality of up to 80%. Various organs play a protective role in shock and contribute to whole-body homeostasis. The ever-increasing number of multidetector CT examinations in severely ill and sometimes unstable patients leads to more frequently encountered findings leading to imminent death, together called "hypovolemic shock complex". Features on CT include dense opacification of the right heart and major systemic veins, venous layering of contrast material and blood, densely opacified parenchyma in the right hepatic lobe, decreased enhancement of the abdominal organ, a dense pulmonary artery, contrast pooling in dependent lungs, and contrast stasis in pulmonary veins. These findings are biomarkers and prognostic indicators of paramount importance which stratify risk and improve patient outcomes. In this review, we illustrate the various CT patterns in shock and review the spectrum and prognostic significance of thoraco-abdominal vascular and visceral alarming signs of impending death with the intention of increasing awareness among radiologists and radiographers to prepare for immediate resuscitation when required.

Accuracy of computed tomography in staging acute appendicitis and its impact on surgical outcome and strategy: a multi-center retrospective case-control study.

INTRODUCTION: The aims of this study were to evaluate the concordance between AAST-CT appendicitis grading criteria, first published in 2014, and surgical findings and to assess the impact of CT staging on the choice of surgical approach. METHODS: This was a multi-center retrospective case-control study including 232 consecutive patients undergoing surgery for acute appendicitis and who had undergone preoperative CT evaluation between 1 January 2017 and 1 January 2022. Appendicitis severity was classified in 5 grades. For each degree of severity, the surgical outcome between patients undergoing open and surgical approach was compared. RESULTS: An almost perfect agreement (k = 0.96) was found between CT and surgery in staging acute appendicitis. The vast majority of patients with grade 1 and 2 appendicitis underwent laparoscopic surgical approach and showed low morbidity rate. In patients with grade 3 and 4 appendicitis, laparoscopic approach was adopted in 70% of cases and was associated, if compared to open, with a higher prevalence of postoperative abdominal collections (p = 0.05; fisher's exact test) and a significantly lower prevalence of surgical site infections (p = 0.0007; fisher's exact test). All the patients with grade 5 appendicitis were treated by laparotomy. CONCLUSIONS: AAST-CT appendicitis grading system seems to show a relevant prognostic value and a potential impact on the choice of surgical strategy, directing toward a laparoscopic approach in patients with grade 1 and 2, an initial laparoscopic approach, replaceable by the open one, for grade 3 and 4 and an open approach in patients with grade 5.

Current Standards for and Clinical Impact of Emergency Radiology in Major Trauma.

In industrialized countries, high energy trauma represents the leading cause of death and disability among people under 35 years of age. The two leading causes of mortality are neurological injuries and bleeding. Clinical evaluation is often unreliable in determining if, when and where injuries should be treated. Traditionally, surgery was the mainstay for assessment of injuries but advances in imaging techniques, particularly in computed tomography (CT), have contributed in progressively changing the classic clinical paradigm for major traumas, better defining the indications for surgery. Actually, the vast majority of traumas are now treated nonoperatively with a significant reduction in morbidity and mortality compared to the past. In this sense, another crucial point is the advent of interventional radiology (IR) in the treatment of vascular injuries after blunt trauma. IR enables the most effective nonoperative treatment of all vascular injuries. Indications for IR depend on the CT evidence of vascular injuries and, therefore, a robust CT protocol and the radiologist's expertise are crucial. Emergency and IR radiologists form an integral part of the trauma team and are crucial for tailored management of traumatic injuries.

MDCT Imaging of Non-Traumatic Thoracic Aortic Emergencies and Its Impact on Diagnosis and Management-A Reappraisal.

Non-traumatic thoracic aorta emergencies are associated with significant morbidity and mortality. Diseases of the intimomedial layers (aortic dissection and variants) have been grouped under the common term of acute aortic syndrome because they are life-threatening conditions clinically indistinguishable on presentation. Patients with aortic dissection may present with a wide variety of symptoms secondary to the pattern of dissection and end organ malperfusion. Other conditions may be seen in patients with acute symptoms, including ruptured and unstable thoracic aortic aneurysm, iatrogenic or infective pseudoaneurysms, aortic fistula, acute aortic thrombus/occlusive disease, and vasculitis. Imaging plays a pivotal role in the patient's management and care. In the emergency room, chest X-ray is the initial imaging test offering a screening evaluation for alternative common differential diagnoses and a preliminary assessment of the mediastinal dimensions. State-of-the-art multidetector computed tomography angiography (CTA) provides a widely available, rapid, replicable, noninvasive diagnostic imaging with sensitivity approaching 100%. It is an impressive tool in decision-making process with a deep impact on treatment including endovascular or open surgical or conservative treatment. Radiologists must be familiar with the spectrum of these entities to help triage patients appropriately and efficiently. Understanding the imaging findings and proper measurement techniques allow the radiologist to suggest the most appropriate next management step.

Acquired peripheral pulmonary artery aneurysms: morphological spectrum of disease and multidetector computed tomography angiography findings-cases series and literature review.

BACKGROUND: Acquired peripheral or intraparenchymal pulmonary artery aneurysms (PPAA) are rare entities but are important to recognize because of the associated morbidity. Hemoptysis is their principal complication and is a potentially fatal condition. PURPOSE: To illustrate the causes, multidetector CT angiography (MDCTA) findings and differential diagnosis of acquired PPAA. MATERIALS AND METHODS: The institutional review boards approved this study. We conducted a retrospective review of the demographic data and the results of clinical and laboratory examinations, and imaging studies of patients managed between January 2012 and January 2017 in two institutions. RESULTS: A total of 19 patients had acquired PPAA that were detected at MDCTA, 9 patients with normal pulmonary artery pressures and 10 with pulmonary hypertension. Nine patients developed PPAA-related acute symptoms. MDCTA features of PPAA include: a lobulated vascular mass, an indistinct irregular arterial wall, aneurysmal thrombosis or wall calcification, findings of impending rupture including perianeurysmal edema, gas or a soft tissue mass. CONCLUSION: PPAA are rare. In our series, endocarditis and pulmonary hypertension are the PPAA leading causes. The treatment modality preferred is embolization, especially as surgery poses a very high risk for patients with severe pulmonary hypertension. Further clarification of the natural history of these rare arterial aneurysms is needed.