Benefits of brain dual-energy CT imaging in detecting intracranial hemorrhage in noncontrast brain CT scans

Abstract Background — Noncontrast brain computed tomography (CT) scans are the gold standard for diagnosing intracranial hemorrhage (ICH). However, the scans have some evaluation limitations, especially in cases of interfering bony artifacts, and overlapping hypoattenuating calcifications and hemorrhages. Material decomposition dual-energy CT (DECT) can separate materials based on atomic numbers. We compare the diagnostic accuracy, sensitivity, and specificity of material decomposition noncontrast DECT of the brain with stimulated conventional 120 kVp-single energy CT (sSECT) imaging for ICH diagnosis. Methods — This retrospective study was conducted at a single center. Three neuroradiologists separately and blindly reviewed the postprocessing images of 111 patients with 215 lesions. DECT acquisitions generated the images. They were in the form of: ♦ sSECT images, ♦ blood-subtracted calcium, nonoverlay images (“blood [calcium] nonoverlay” images), ♦ blood-subtracted calcium, overlay images with rainbow and grayscale color-coding (“blood [calcium] overlay” images), and ♦ combined sSECT and blood-subtracted calcium, overlay images (“combined sSECT + blood (calcium) overlay” images). Results — Compared with the sSECT images, the blood (calcium) overlay images had better accuracy (99.6%), sensitivity (99.5%), and specificity (100%) for ICH diagnosis. The blood (calcium) overlay images also provided better observer confidence (a 94.06% certain diagnosis) than the sSECT images (P < 0.05). The blood (calcium) overlay images and combined images had very good interrater reliability, whereas the reliability of the sSECT images was poor. Conclusions — Material decomposition DECT—as either blood (calcium) overlay images or combined sSECT + blood (calcium) overlay images—has a high ICH diagnostic ability in noncontrast brain CT imaging.