In vivo detection of macrophages in human carotid atheroma temporal dependence of ultrasmall superparamagnetic particles of iron oxide-enhanced MRI

• Published in: Stroke (1970) Vol. 35; no. 7; pp. 1631 - 1635
• Main Authors: TRIVEDI, Rikin A, U-KING-IM, Jean-Marie, LIQUN WANG, KIRKPATRICK, Peter J, BROWN, John, GILLARD, Jonathan H, GRAVES, Martin J, CROSS, Justin J, HORSLEY, Jo, GODDARD, Martin J, SKEPPER, Jeremy N, QUARTEY, George, WARBURTON, Elizabeth, JOUBERT, Ilse
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 01.07.2004
• Subjects: Aged; Arteriosclerosis - blood; Arteriosclerosis - diagnosis; Arteriosclerosis - pathology; Biological and medical sciences; Carotid Arteries - pathology; Carotid Stenosis - blood; Carotid Stenosis - diagnosis; Carotid Stenosis - pathology; Contrast Media - administration & dosage; Dextrans; Female; Ferrosoferric Oxide; Humans; Iron; Macrophages - pathology; Magnetic Resonance Imaging - methods; Magnetite Nanoparticles; Male; Medical sciences; Middle Aged; Neurology; Oxides; Vascular diseases and vascular malformations of the nervous system; Human; atherosclerosis; Stroke; Nervous system diseases; magnetic resonance imaging; Cardiovascular disease; Iron; carotid arteries; Medical screening; Nuclear magnetic resonance imaging; Cerebral disorder; Vascular disease; macrophages; Carotid; Central nervous system disease; Dependence; Atheroma; Cerebrovascular disease; Macrophage
• ISSN: 0039-2499; 1524-4628
• DOI: 10.1161/01.STR.0000131268.50418.b7

Background- It has been suggested that inflammatory cells within vulnerable plaques may be visualized by superparamagnetic iron oxide particle-enhanced MRI. The purpose of this study was to determine the time course for macrophage visualization with in vivo contrast-enhanced MRI using an ultrasmall superparamagnetic iron oxide (USPIO) agent in symptomatic human carotid disease. Eight patients scheduled for carotid endarterectomy underwent multisequence MRI of the carotid bifurcation before and 24, 36, 48, and 72 hours after Sinerem (2.6 mg/kg) infusion. USPIO particles accumulated in macrophages in 7 of 8 patients given Sinerem. Areas of signal intensity reduction, corresponding to USPIO/macrophage-positive histological sections, were visualized in all 7 of these patients, optimally between 24 and 36 hours, decreasing after 48 hours, but still evident up to 96 hours after infusion. USPIO-enhanced MRI of carotid atheroma can be used to identify macrophages in vivo. The temporal change in the resultant signal intensity reduction on MRI suggests an optimal time window for the detection of macrophages on postinfusion imaging.