MR imaging detection of calcified intracranial lesions and differentiation from iron‐laden lesions

Abstract

Magnetic susceptibility variation caused by calcium permits limited detection of intracranial calcificatios and/or their distinction from iron‐laden lesions with spin‐echo or gradient‐echo magnetic resonance (MR) techniques. The magnetic susceptibility sensitivity of phase imaging has been used to detect iron‐laden lesions. A new approach that combines the magnetic susceptibility sensitivity of both gradient‐echo and phase imaging to yield greater imaging sensitivity to calcium is presented. Two‐dimensional fast low‐angle shot (FLASH) gradient‐echo imaging with phase image reconstruction (gradient‐echo phase [GEP]) was used at 1.0 and 1.5 T. Twelve patients with computed tomography‐proved calcified intracranial lesions (≥200 HU) and seven patients with iron‐laden intracranial lesions having a characteristic appearance on T1‐and T2‐weighted and FLASH MR images were studied. The GEP imaging technique helped detect calcified intracranial lesions (≥200 HU) and helped distinguish them from iron‐laden lesions.