Dual-energy direct bone removal CT angiography for evaluation of intracranial aneurysm or stenosis: comparison with conventional digital subtraction angiography

• Published in: European radiology 2009-04, Vol.19 (4), p.1019-1024
• Main Authors: Watanabe, Yoshiyuki, Uotani, Kensuke, Nakazawa, Tetsuro, Higashi, Masahiro, Yamada, Naoaki, Hori, Yoshiro, Kanzaki, Suzu, Fukuda, Tetsuya, Itoh, Toshihide, Naito, Hiroaki
• Format: Article
• Language: English
• Subjects: Adult; Aged; Angiography, Digital Subtraction - methods; Bone and Bones - pathology; Brain - metabolism; Constriction, Pathologic; Diagnostic Imaging - methods; Diagnostic Radiology; Female; Humans; Image Processing, Computer-Assisted; Imaging; Internal Medicine; Interventional Radiology; Intracranial Aneurysm - diagnosis; Intracranial Aneurysm - diagnostic imaging; Male; Medicine; Medicine & Public Health; Middle Aged; Neuro; Neuroradiology; Radiology; Software; Tomography, X-Ray Computed - methods; Ultrasound
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-008-1213-5

Dual-energy CT can be applied for bone elimination in cerebral CT angiography (CTA). The aim of this study was to compare the results of dual-energy direct bone removal CTA (DE-BR-CTA) with those of digital subtraction angiography (DSA). Twelve patients with intracranial aneurysms and/or ICA stenosis underwent a dual-source CT in dual-energy mode. Post-processing software selectively removed bone structures using the two energy data sets. Three-dimensional images with and without bone removal were reviewed and compared to DSA. Dual-energy bone removal was successful in all patients. For 10 patients, bone removal was good and CTA maximum-intensity projection (MIP) images could be used for vessel evaluation. For two patients, bone removal was moderate with some bone remnants, but this did not inhibit the three-dimensional visualization. Three aneurysms adjacent to the skull base were only partially visible in conventional CTA but were fully visible in DE-BR-CTA. In five patients with ICA stenosis, DE-BR-CTA revealed the stenotic lesions on the MIP images. The correlation between DSA and DE-BR-CTA was good ( R 2 =0.822), but DE-BR-CTA led to an overestimation of stenosis. DE-BR-CTA was able to eliminate bone structure using only a single CT data acquisition and is useful to evaluate intracranial aneurysms and stenosis.