Selecting a contrast medium for MDCT investigation

Abstract

Most procedures performed with multidetector computed tomography (MDCT) require the administration of a contrast medium (CM). In choosing a CM, it is important to consider the tolerability profile of the CM and whether sufficient contrast enhancement will be achieved. Low-osmolar CM (LOCM) are the most widely used and are well tolerated in most patients. However, some patients (e. g. those with renal insufficiency, diabetes and the elderly) are at significant risk of contrast-induced nephropathy (CIN), which can compromise the benefits of the procedure. Iodixanol is an iso-osmolar CM that compares favourably with LOCM in terms of contrast enhancement and is also associated with less pain or discomfort on injection. In patients with renal impairment and diabetes undergoing angiography, a significantly lower incidence of CIN was reported with iodixanol compared with iohexol (iodixanol, 3.1%; iohexol, 26.2%; P = 0.002). A second study in patients with renal insufficiency undergoing CT angiography reported a 9% incidence of CIN; no patients developed renal failure and all recovered.