Safe and Informed Use of Gadolinium-Based Contrast Agent in Body Magnetic Resonance Imaging: Where We Were and Where We Are.

Gadolinium-based contrast agents (GBCAs) have helped to improve the role of magnetic resonance imaging (MRI) for the diagnosis and treatment of diseases. There are currently nine different commercially available gadolinium-based contrast agents (GBCAs) that can be used for body MRI cases, and which are classifiable according to their structures (cyclic or linear) or biodistribution (extracellular-space agents, target/specific-agents, and blood-pool agents). The aim of this review is to illustrate the commercially available MRI contrast agents, their effect on imaging, and adverse reaction on the body, with the goal to lead to their proper selection in different clinical contexts. When we have to choose between the different GBCAs, we have to consider several factors: (1) safety and clinical impact; (2) biodistribution and diagnostic application; (3) higher relaxivity and better lesion detection; (4) higher stability and lower tissue deposit; (5) gadolinium dose/concentration and lower volume injection; (6) pulse sequences and protocol optimization; (7) higher contrast-to-noise ratio at 3.0 T than at 1.5 T. Knowing the patient's clinical information, the relevant GBCAs properties and their effect on body MRI sequences are the key features to perform efficient and high-quality MRI examination.

Value of multidetector computed tomography angiography in severe non-variceal upper gastrointestinal bleeding: a retrospective study in a referral bleeding unit.

BACKGROUND: Non-variceal upper gastrointestinal bleeding is a common gastroenterological emergency associated with significant morbidity and mortality. Upper gastrointestinal endoscopy is currently recommended as the gold standard modality for both diagnosis and treatment. As historically played a limited role in the diagnosis of acute non-variceal upper gastrointestinal bleeding, multidetector-row computed tomography angiography is emerging as a promising tool in the diagnosis of non-variceal upper gastrointestinal bleeding, especially for severe cases. However, to date, evidence concerning the role of multidetector-row computed tomography angiography in the non-variceal upper gastrointestinal bleeding diagnosis is still lacking. AIM: The purpose of this study was to retrospectively investigate the diagnostic performance of emergent multidetector-row computed tomography angiography performed prior to any diagnostic modality or following urgent upper endoscopy to identify the status, the site, and the underlying etiology of severe non-variceal upper gastrointestinal bleeding. METHODS: Institutional databases were reviewed in order to identify severe acute non-variceal upper gastrointestinal bleeding patients who were admitted to our bleeding unit and were referred for emergent multidetector-row computed tomography angiography prior to any hemostatic treatment (< 3 h) or following (< 3 h) endoscopy, between December 2019 and October 2022. The study aim was to evaluate the diagnostic performance of multidetector-row computed tomography angiography to detect the status, the site, and the etiology of severe non-variceal upper gastrointestinal bleeding with endoscopy, digital subtraction angiography, surgery, pathology, or a combination of them as reference standards. RESULTS: A total of 68 patients (38 men, median age 69 years [range 25-96]) were enrolled. The overall multidetector-row computed tomography angiography sensitivity, specificity, and accuracy to diagnose bleeding status were 77.8% (95% CI: 65.5-87.3), 40% (95% CI: 5.3-85.3), and 75% (95% CI: 63.0-84.7), respectively. Finally, the overall multidetector-row computed tomography angiography sensitivity to identify the bleeding site and the bleeding etiology were 92.4% (95% CI: 83.2-97.5) and 79% (95% CI: 66.8-88.3), respectively. CONCLUSION: Although esophagogastroduodenoscopy is the mainstay in the diagnosis and treatment of most non-variceal upper gastrointestinal bleeding cases, multidetector-row computed tomography angiography seems to be a feasible and effective modality in detecting the site, the status, and the etiology of severe acute non-variceal upper gastrointestinal bleeding. It may play a crucial role in the management of selected cases of non-variceal upper gastrointestinal bleeding, especially those clinically severe and/or secondary to rare and extraordinary rare sources, effectively guiding timing and type of treatment. However, further large prospective studies are needed to clarify the role of multidetector-row computed tomography angiography in the diagnostic process of acute non-variceal upper gastrointestinal bleeding.

Point-of-Care Lung Ultrasound in the Intensive Care Unit-The Dark Side of Radiology: Where Do We Stand?

Patients in intensive care units (ICUs) are critically ill and require constant monitoring of clinical conditions. Due to the severity of the underlying disease and the need to monitor devices, imaging plays a crucial role in critically ill patients' care. Given the clinical complexity of these patients, who typically need respiratory assistance as well as continuous monitoring of vital functions and equipment, computed tomography (CT) can be regarded as the diagnostic gold standard, although it is not a bedside diagnostic technique. Despite its limitations, portable chest X-ray (CXR) is still today an essential diagnostic tool used in the ICU. Being a widely accessible imaging technique, which can be performed at the patient's bedside and at a low healthcare cost, it provides additional diagnostic support to the patient's clinical management. In recent years, the use of point-of-care lung ultrasound (LUS) in ICUs for procedure guidance, diagnosis, and screening has proliferated, and it is usually performed at the patient's bedside. This review illustrates the role of point-of-care LUS in ICUs from a purely radiological point of view as an advanced method in ICU CXR reports to improve the interpretation and monitoring of lung CXR findings.

Hepatobiliary-specific magnetic resonance contrast agents: role in biliary trauma.

Non-iatrogenic traumatic bile duct injuries (NI-TBIs) are a rare complication after abdominal trauma, with an estimated prevalence of 2.8-7.4% in patients underwent blunt liver injuries. They may be overlooked in patients with extensive multi-organ trauma, particularly hepatic, splenic and duodenal injuries, which have a prevalence of 91%, 54% and 54%, respectively. Whole body contrast-enhanced computed tomography (CE-CT) represents the examination of choice in polytraumatized hemodynamically stable patients, as it allows a comprehensive evaluation of vascular, parenchymal, bone and soft tissues injuries, but the diagnosis of any biliary leaks is limited to the evaluation of nonspecific imaging findings and on findings evolution in the follow-up, such as the progressive growth of fluid collections. Furthermore, biliary complications, such as the occurrence of biloma or biliary peritonitis, may become manifest several days after the initial trauma, often with unspecific progressive signs and symptoms. Although CT and ultrasonography can suggest bile leaks based on several nonspecific imaging findings (e.g., fluid collections), magnetic resonance imaging (MRI) using hepatobiliary contrast agents helps to identify the site and entity of post-traumatic biliary disruption. Indeed, MRI allows to obtain cholangiographic sequences that may show post-traumatic active bile leakage and cysto-biliary communications by direct visualisation of contrast material extravasation into fluid collections, increasing the preoperative accuracy of NI-TBIs. Few data are available about MRI use in the follow-up of trauma with NI-TBI management. So, in the present mini review, its role is reviewed and our preliminary experience in this field is reported.

MRI-Cavernosography: A New Diagnostic Tool for Erectile Dysfunction Due to Venous Leakage: A Diagnostic Chance.

Erectile dysfunction caused by venous leakage is a vascular disease in which blood fails to accumulate in the corpora cavernosa due to the abrupt drainage of blood from the penis secondary to an abnormal venous network that affects 1 to 2% of men under 25 years old and about 10 to 20% over 60 years old, who do not raise a sufficient erection for penetrative sex. The study of the venous leak and its characterization in young patients with erectile dysfunction represent a diagnostic challenge, and imaging remains the best way to diagnose this condition. In the article, it is described the methods of execution and the diagnostic role of the cavernous MRI in the study of vasogenic erectile dysfunction from the venous leak, proposing it as a good alternative to the cavernous CT, considering the satisfactory results in terms of diagnostic interpretation, the absence of ionizing radiation, the higher soft tissue resolution of the imaging method and the lower administration of contrast agent.

The Role of CT-Angiography in the Acute Gastrointestinal Bleeding: A Pictorial Essay of Active and Obscure Findings.

Gastrointestinal bleeding is a potentially life-threatening abdominal emergency that remains a common cause of hospitalisation. Although 80-85% of cases of gastrointestinal bleeding resolve spontaneously, it can result in massive haemorrhage and death. The presentation of gastrointestinal bleeding can range from asymptomatic or mildly ill patients requiring only conservative treatments to severely ill patients requiring immediate intervention. Identifying the source of the bleeding can be difficult due to the wide range of potential causes, the length of the gastrointestinal tract and the intermittent nature of the bleeding. The diagnostic and therapeutic approach is fully dependent on the nature of the bleeding and the patient's haemodynamic status. Radiologists should be aware of the appropriate uses of computed tomography angiography and other imaging modalities in patients with acute gastrointestinal bleeding, as well as the semiotics of bleeding and diagnostic pitfalls in order to appropriately diagnose and manage these patients. The learning objective of this review is to illustrate the computed tomography angiography technique, including the potential role of dual-energy computed tomography angiography, also highlighting the tips and tricks to identify the most common and uncommon features of acute gastrointestinal bleeding and its obscure form.

Stocky/Packed Pancreas: A Case of Focal Drug-Induced Acute Pancreatitis Mimicking Cancer.

Drug-induced acute pancreatitis (DIP) is a recognised but underreported entity in the literature. Immunotherapy drugs have been described as one possible emerging cause, although the pathogenic mechanism is still largely unclear. To date, only a few cases have been reported, even if in recent times there is an over-increasing awareness of this pathologic entity. The imaging-based diagnosis of DIP can be difficult to establish, representing a real challenge for a radiologist, especially when the inflammatory disease appears as a focal mass suspicious for a malignancy. Case report: We herein report the case of a 71-year-old man with a known history of partially responsive lung adenocarcinoma subtype with high programmed cell death ligand 1 (PD-L1) expression, who underwent positron emission tomography (PET)/computed tomography (CT) imaging follow-up after one year of immunotherapy. The exam revealed a stocky/packed lesion in the pancreatic body, with increased 18F-fluorodeoxyglucose (FDG) accumulation highly suggestive of pancreatic cancer, which finally was proven to be a DIP induced by immunotherapy. Conclusion: Distinguishing between focal DIP and pancreatic neoplasm is, therefore, crucial for timely therapeutic management and prognostic stratification. A deep knowledge of possible imaging pitfalls coupled with a comprehensive clinical and laboratory assessment is pivotal to avoid any delays in diagnosis.

The Technique and Advantages of Contrast-Enhanced Ultrasound in the Diagnosis and Follow-Up of Traumatic Abdomen Solid Organ Injuries.

Trauma is one of the most common causes of death or permanent disability in young people, so a timely diagnostic approach is crucial. In polytrauma patients, CEUS (contrast enhanced ultrasound) has been shown to be more sensitive than US (ultrasound) for the detection of solid organ injuries, improving the identification and grading of traumatic abdominal lesions with levels of sensitivity and specificity similar to those seen with MDCT (multidetector tomography). CEUS is recommended for the diagnostic evaluation of hemodynamically stable patients with isolated blunt moderate-energy abdominal traumas and the diagnostic follow-up of conservatively managed abdominal traumas. In this pictorial review, we illustrate the advantages and disadvantages of CEUS and the procedure details with tips and tricks during the investigation of blunt moderate-energy abdominal trauma as well as during follow-up in non-operative management.

Computed tomography imaging of septic shock. Beyond the cause: the "CT hypoperfusion complex". A pictorial essay.

Septic shock is a medical emergency that represents one of the most important underlying causes for presentation to the Emergency Department. Sepsis is defined as organ dysfunction, life-threatening event caused by a deregulated inflammatory host response to infection, with a mortality risk ranging from 10 to 40%. Early sepsis identification is the cornerstone of management and diagnostic imaging can play a pivotal role in this clinical context. The choice of imaging modality depends on several factors, associated with the clinical condition and the presence or absence of localising signs and symptoms. The diagnostic accuracy of contrast-enhanced total-body CT has been well established during septic shock, allowing for a rapid, panoramic, and detailed study of multiple body areas, simultaneously. The aim of this article is to illustrate the controversial CT hypoperfusion complex in patients with septic shock, characterised by the following imaging features: decreased enhancement of the viscera; increased mucosal enhancement; luminal dilation of the small bowel; mural thickening and fluid-filled loops of the small bowel; the halo sign and flattening of the inferior vena cava; reduced aortic diameter; peripancreatic oedema; abnormal parenchymal perfusion; and other controversial findings that are variably associated with each other and reversible during the early stages. Increasing physicians' awareness of the significance of these findings could prompt alternative approaches to the early assessment and management of septic shock. In this perspective, CT imaging represents a useful tool for a complete, rapid and detailed diagnosis of clinically suspected septic shock, which can be used to improve patient outcomes.