title: Dual-energy direct bone removal CT angiography for evaluation of intracranial aneurysm or stenosis: comparison with conventional digital subtraction angiography.
abstract: 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.
authors.affiliation: Department of Radiology, National Cardiovascular Center, Osaka, Japan. yowatana@luke.or.jp
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Kensuke
authors.initials: K
authors.lastname: Uotani
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Nakazawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Higashi
authors.forename: Naoaki
authors.initials: N
authors.lastname: Yamada
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Hori
authors.forename: Suzu
authors.initials: S
authors.lastname: Kanzaki
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Fukuda
authors.forename: Toshihide
authors.initials: T
authors.lastname: Itoh
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Naito
mesh_terms: D000328:Adult; D000368:Aged; D015901:Angiography, Digital Subtraction / Q000379:methods*; D001842:Bone and Bones / Q000473:pathology; D001921:Brain / Q000378:metabolism; D003251:Constriction, Pathologic; D003952:Diagnostic Imaging / Q000379:methods; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*