Side Effects and Complications of Magnetic Resonance Contrast Media

Contrast media used in radiology are iodine based for computed tomography (CT) examinations and gadolinium based for magnetic resonance imaging (MRI) examinations. Initially, gadolinium based contrast media were thought to be safe and non-nephrotoxic. Later on, several studies revealed that they can also be nephrotoxic at increased doses. Additionally, another complication from their use is systematic nephrogenic fibrosis. Gadolinium based contrast media can be safe in healthy and renal insufficiency patients if used at specific doses. These complications are herein briefly reviewed and guidelines and techniques for their avoidance are discussed

Contrast-enhanced ultrasound performed under urgent conditions. Indications, review of the technique, clinical examples and limitations

Contrast-enhanced ultrasound (CEUS) is an imaging technique with various indications, most of which refer to scheduled examinations. However, CEUS can also be performed under urgent conditions for the investigation of many different clinical questions. This article reviews basic physics of ultrasound contrast agents and examines the commonest urgent clinical applications of CEUS. These include, among others, abdominal solid organ trauma and infarcts, scrotal and penile pathology and blood vessel imaging. Patients can be examined with a very short time delay at their bedside, without exposure to ionising radiation or risk of anaphylactic reaction and renal failure, while contraindications are minimal. CEUS technique is described for various urgent indications and imaging examples from our department’s experience are presented. Safety matters and limitations of CEUS are also mentioned. Teaching Points Contrast-enhanced ultrasound (CEUS) can be performed urgently for various clinical applications. Abdominal indications include solid organ trauma and infarcts. CEUS in abdominal organ trauma correlates well with CT and can replace it for patient follow-up. CEUS images testicular torsion, infection and infarction, as well as testicular and penile trauma. Blood vessels can be assessed with CEUS for obstruction, aneurysm, thrombosis and dissection

Imaging of Cardiac Tumors and Masses

Objective: As noninvasive imaging is gaining widespread acceptance, the aim of the present study was to review our experience with the use of cross sectional imaging modalities to evaluate cardiac tumors and masses.  Background: Proper diagnosis of the type and extension of a cardiac tumor or mass is very important for therapy planning. Echocardiography has an established role as a non-invasive diagnostic imaging modality. Computed tomography (CT) and magnetic resonance imaging (MRI) also provide adequate delineation of cardiac tumors and masses.  Methods: Twenty-two patients referred to our department with a suspected cardiac mass, previously detected by cardiac ultrasound, were evaluated by CT (12 patients) and MRI (4 patients). Six patients were examined by both modalities. In 2 cases of staging of a known primary neoplasm and one case of a suspected epicardiac lesion, positron emission tomography (PET-CT) was performed. The CT cardiac examinations were performed using a 16-slice multislice scanner with ECG gating. The MRI examination was performed on a 1.5 Tesla MRI scanner using an ECG-gated cardiac protocol and the PET-CT examination was performed on an integrated PET-CT four-slice scanner, using 370 mMBq of fluorodeoxyglucose.   Results: Twenty-two cardiac masses were successfully detected and their characteristics adequately delineated, including eight myxomas, one angiosarcoma, one ventricular lymphoma, one endocardiac metastasis, one epicardiac paraganglioma, and 10 cases of intracardiac thrombi.  Conclusion: CT and MRI are noninvasive imaging modalities which can delineate cardiac tumors and masses and provide essential information for adequate diagnosis, staging and treatment planning. Compared to cardiac ultrasound, CT and MRI are superior in preoperative planning. Key words: cardiac tumors,  cross sectional imaging modalities, computed tomography, magnetic resonance imaging&nbsp

Bilateral inferior petrosal sinuses sampling in the routine investigation of Cushing's syndrome: A comparison with MRI

OBJECTIVE: Identifying the cause of Cushing’s syndrome (CS) is a perplexing issue. Bilateral inferior petrosal sinuses sampling (BIPSS) is an invasive and elaborate but established procedure in distinguishing Cushing’s disease (CD) from ectopic adrenocorticotropic hormone (ACTH) syndrome. We compare the diagnostic performance of BIPSS and MRI in detecting an ACTH-secreting source, and we suggest the diagnostic protocol that we found beneficial for the management of patients with CS. MATERIALS AND METHODS: Seventy-eight consecutive patients with CS were included. All patients underwent biochemical investigation and pituitary MRI. Consequently, patients were routinely referred for BIPSS; 25 received stimulation with corticotropin-releasing hormone (CRH) and 53 with CRH and desmopressin. The diagnosis of CD was established on the basis of complementary biochemical, imaging, and BIPSS criteria. The diagnostic performances of BIPSS and MRI were calculated for patients with final diagnosis. RESULTS: A final diagnosis was available for 54 patients (46 CD confirmed, five ectopic confirmed, three adrenals). No (known) patient was rnisclassified based on our suggested diagnostic criteria. MRI rendered 25 false-negatives and two false-positives (incidentalomas). Successful BIPSS yielded two false-negatives and three false-positives (adrenals). The calculated accuracy for detecting a pituitary source of ACTH was 50% and 88% for MRI and successful BIPSS, respectively. CONCLUSION: MRI is of only limited diagnostic performance, while BIPSS is the most accurate way to establish the diagnosis of CD. The routine use of a multimodality diagnostic approach including BIPSS, MRI, and biochemical tests is suggested to avoid the risk of mismanagement for patients with CS