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.

Combined DSA- and US-guided management of acute bleeding: effectiveness of percutaneous glue embolization in six cases.

AIMS: This study aims to report on safety and effectiveness of glue embolization of acute hemorrhages performed by US-guided percutaneous direct puncture, in patients where the standard endovascular approach is technically unfavourable. METHODS: In this single center retrospective analysis, patients affected by traumatic or non traumatic acute hemorrhages were treated with glue embolization technically performed by US-guided direct puncture. Patients suffered from active bleeding detected at contrast-enhanced Computer Tomography and confirmed at Digital Subtracted Arteriography, with concomitant hemoglobin drop and blood pressure reduction. Six patients were reviewed; hemorrhages occurred in liver parenchima (1), gallbladder (1) and lower limbs (4). Bleedings etiologies were post-traumatic (5) and inflammatory (1); four had extraluminal blushes while 2 were pseudoaneurysms. In five cases (4 limbs and 1 hepatic bleedings) the direct-puncture approach was adopted because of technically unfavourable vascular anatomy for superselective embolization; in one case (cystic artery pseudoaneurysm), an endovascular embolization would entail a high risk of gallbladder ischemia because of its terminal arterial supply. Technical success was defined disappearance of bleeding signs at last arteriography; clinical success was considered stabilization and/or improvement of hemoglobin values and arterial pressure without additional interventions. RESULTS: Both technical and clinical successes were obtained in 100% of the cases without major complications. No needle occlusion occurred during glue injection. CONCLUSIONS: In this study percutaneous US-guided embolization by direct puncture was a safe and effective approach to manage acute bleedings; it could be considered as an alternative in patients with unfavourable vascular anatomy for the standard catheter-directed endovascular embolization.

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.

Abdominal compartment syndrome: what radiologist needs to know.

The intra-abdominal hypertension (IAH) and the abdominal compartment syndrome (ACS) are life-threatening conditions with a significant rate of mortality; therefore, early detection is paramount in their optimal management. IAH is diagnosed when the intra-abdominal pressure (IAP) is more than 12 mmHg. It can occur when the intra-abdominal volume increases (ileus, ascites, trauma, pancreatitis, etc.) and/or the abdominal wall compliance decreases. IAH can cause decreased venous flow, low cardiac output, renal impairment, and decreased respiratory compliance. Consequently, these complications can lead to multiple organ failure and induce the abdominal compartment syndrome (ACS) when IAP rises above 20 mmHg. The diagnosis is usually made with intravesical pressure measurement. However, this measurement was not always possible to obtain; therefore, alternative diagnostic techniques should be considered. In this setting, computed tomography (CT) may play a crucial role, allowing the detection and characterization of pathological conditions that may lead to IAH. This review is focused on the pathogenesis, clinical features, and radiological findings of ACS, because their presence allows radiologists to raise the suspicion of IAH/ACS in critically ill patients, guiding the most appropriate treatment.

Rare causes of acute non-variceal upper gastrointestinal bleeding: A comprehensive review.

Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common gastroenterological emergency associated with significant morbidity and mortality. Gastroenterologists and other involved clinicians are generally assisted by international guidelines in its management. However, NVUGIB due to peptic ulcer disease only is mainly addressed by current guidelines, with upper gastrointestinal endoscopy being recommended as the gold standard modality for both diagnosis and treatment. Conversely, the management of rare and extraordinary rare causes of NVUGIB is not covered by current guidelines. Given they are frequently life-threatening conditions, all the involved clinicians, that is emergency physicians, diagnostic and interventional radiologists, surgeons, in addition obviously to gastroenterologists, should be aware of and familiar with their management. Indeed, they typically require a prompt diagnosis and treatment, engaging a dedicated, patient-tailored, multidisciplinary team approach. The aim of our review was to extensively summarize the current evidence with regard to the management of rare and extraordinary rare causes of NVUGIB.

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.

New Technologies in the Assessment of Carotid Stenosis: Beyond the Color-Doppler Ultrasound-High Frame Rate Vector-Flow and 3D Arterial Analysis Ultrasound.

Atherosclerotic plaque in the carotid artery is the main cause of ischemic stroke, with a high incidence rate among people over 65 years. A timely and precise diagnosis can help to prevent the ischemic event and decide patient management, such as follow up, medical, or surgical treatment. Presently, diagnostic imaging techniques available include color-Doppler ultrasound, as a first evaluation technique, computed tomography angiography, which, however, uses ionizing radiation, magnetic resonance angiography, still not in widespread use, and cerebral angiography, which is an invasively procedure reserved for therapeutically purposes. Contrast-enhanced ultrasound is carving out an important and emerging role which can significantly improve the diagnostic accuracy of an ultrasound. Modern ultrasound technologies, still not universally utilized, are opening new horizons in the arterial pathologies research field. In this paper, the technical development of various carotid artery stenosis diagnostic imaging modalities and their impact on clinical efficacy is thoroughly reviewed.

The Dark Side of Ultrasound Imaging in Parathyroid Disease.

The diagnosis of parathyroid diseases by imaging still has some intrinsic technical limitations due to the differential diagnosis of different structures of the neck that mimic the parathyroid glands. In this view, ultrasound (US) is an established, low-cost, and non-invasive imaging technique that still represents the first-line approach for evaluating patients with parathyroid disease. The objective of this article is to provide a comprehensive review of the applications of USs in clinical practice, discussing the histopathological and US characteristics of the parathyroid glands in normal and pathological conditions, the advantages of preoperative imaging, and novel updates on the most useful and currently available multiparameter US techniques.

Non-Operative Management of Polytraumatized Patients: Body Imaging beyond CT.

In the transition from the operative to the conservative approach for the polytraumatized patients who undergo blunt trauma, diagnostic imaging has assumed a pivotal role, currently offering various opportunities, particularly in the follow-up of these patients. The choice of the most suitable imaging method in this setting mainly depends on the injury complications we are looking for, the patient conditions (mobilization, cooperation, medications, allergies and age), the biological invasiveness, and the availability of each imaging method. Computed Tomography (CT) represents the "standard" imaging technique in the polytraumatized patient due to the high diagnostic performance when a correct imaging protocol is adopted, despite suffering from invasiveness due to radiation dose and intravenous contrast agent administration. Ultrasound (US) is a readily available technology, cheap, bedside performable and integrable with intravenous contrast agent (Contrast enhanced US-CEUS) to enhance the diagnostic performance, but it may suffer particularly from limited panoramicity and operator dependance. Magnetic Resonance (MR), until now, has been adopted in specific contexts, such as biliopancreatic injuries, but in recent experiences, it showed a great potential in the follow-up of polytraumatized patients; however, its availability may be limited in some context, and there are specific contraindications, such as as claustrophobia and the presence non-MR compatible devices. In this article, the role of each imaging method in the body-imaging follow-up of adult polytraumatized patients will be reviewed, enhancing the value of integrated imaging, as shown in several cases from our experience.

Multimodality ultrasound assessment of the spleen: Normal appearances and emergency abnormalities.

This paper summarizes the main splenic emergencies and their ultrasonographic findings to orient appropriate patient management. US requires minimal preparation time and allows to examine the parenchyma and to detect intraperitoneal fluid collections, which may be indirect evidence of solid organ injuries. In this paper, we analyze the role of B-mode, Doppler and Contrast-Enhanced Ultrasound in the diagnosis of splenic emergencies, with a particular focus on splenic infarction, infection, traumatic injuries and vascular splenic anomalies.

An update on pyelonephritis: role of contrast enhancement ultrasound (CEUS).

Acute pyelonephritis (APN) is a bacterial infection causing inflammation of the kidneys. Diagnosis is usually based on clinical and laboratory findings. Imaging is required if a complication is suspected in acute pyelonephritis to assess the nature and extent of the lesions and to detect underlying causes. CT represents the current imaging modality of choice in clinical practice. CEUS is an alternative that has been proven to be equally accurate in the detection of acute pyelonephritis renal lesions. CEUS allows us to distinguish small simple nephritic involvement from abscess complications and to follow their evolution over time during antibiotic therapy. The absence of ionizing radiation and the lack of nephrotoxicity make CEUS an ideal tool in the study of pyelonephritis.

The role of computed tomography for the prediction of esophageal variceal bleeding: Current status and future perspectives.

Esophageal variceal bleeding (EVB) is one of the most common and severe complications related to portal hypertension (PH). Despite marked advances in its management during the last three decades, EVB is still associated with significant morbidity and mortality. The risk of first EVB is related to the severity of both PH and liver disease, and to the size and endoscopic appearance of esophageal varices. Indeed, hepatic venous pressure gradient (HVPG) and esophagogastroduodenoscopy (EGD) are currently recognized as the "gold standard" and the diagnostic reference standard for the prediction of EVB, respectively. However, HVPG is an invasive, expensive, and technically complex procedure, not widely available in clinical practice, whereas EGD is mainly limited by its invasive nature. In this scenario, computed tomography (CT) has been recently proposed as a promising modality for the non-invasive prediction of EVB. Although CT is only a diagnostic modality, thus being not capable of supplanting EGD or HVPG in providing therapeutic and physiological data, it could potentially assist liver disease scores, HVPG, and EGD in a more effective prediction of EVB. However, to date, evidence concerning the role of CT in this setting is still lacking. Our review aimed to summarize and discuss the current evidence concerning the role of CT in predicting the risk of EVB.

Role of multidetector computed tomography angiography in non-variceal upper gastrointestinal bleeding: A comprehensive review.

Non-variceal upper gastrointestinal bleeding (NVUGIB) 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, with computed tomography traditionally playing a limited role in the diagnosis of acute NVUGIB. Following the introduction of multidetector computed tomography (MDCT), this modality is emerging as a promising tool in the diagnosis of NVUGIB. However, to date, evidence concerning the role of MDCT in the NVUGIB diagnosis is still lacking. The aim of our study was to review the current evidence concerning the role of MDCT in the diagnosis of acute NVUGIB.

Common, Less Common, and Unexpected Complications after Bariatric Surgery: A Pictorial Essay.

Bariatric surgery has demonstrated a higher rate of success than other nonsurgical treatments in selected patients with obesity; however, like all medical procedures, postoperative complications may occur, ranging between 2 and 10% and, although rare, they can be life threatening. Complications may be unspecific (any surgery-related complications) or specific (linked to the specific surgical procedure) and can be distinguished as common, less common, and unexpected. According to the onset, they may be acute, when occurring in the first 30 days after surgery, or chronic, with a presentation after 30 days from the procedure. The aim of this pictorial essay is to review the radiological aspects of surgical techniques usually performed and the possible complications, in order to make radiologists more confident with the postsurgical anatomy and with the normal and abnormal imaging findings.

Massive bleeding from gastric submucosal arterial collaterals secondary to splenic artery thrombosis: A case report.

BACKGROUND: Gastric submucosal arterial collaterals (GSAC) secondary to splenic artery occlusion is an extraordinary rare and potentially life-threatening cause of acute upper gastrointestinal bleeding. Here, we report a case of massive bleeding from GSAC successfully treated by means of a multidisciplinary minimally invasive approach. CASE SUMMARY: A 60-year-old non-cirrhotic gentleman with a history of arterial hypertension was admitted due to hematemesis. Emergent esophagogastroduodenoscopy revealed pulsating and tortuous varicose shaped submucosal vessels in the gastric fundus along with a small erosion overlying one of the vessels. In order to characterize the fundic lesion, pre-operative emergent computed tomography-angiography was performed showing splenic artery thrombosis (SAT) and tortuous arterial structures arising from the left gastric artery and the left gastroepiploic artery in the gastric fundus. GSAC was successfully treated by means of a minimally invasive step-up approach consisting in endoscopic clipping followed by transcatheter arterial embolization (TAE). CONCLUSION: This was a previously unreported case of bleeding GSAC secondary to SAT successfully managed by means of a multidisciplinary minimally invasive approach consisting in endoscopic clipping for the luminal bleeding control followed by elective TAE for the definitive treatment.

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.