Usefulness of monochromatic imaging with metal artifact reduction software for computed tomography angiography after intracranial aneurysm coil embolization.
BACKGROUND
Recently, a newly developed fast-kV switching dual energy CT scanner with a gemstone detector generates virtual high keV images as monochromatic imaging (MI). Each MI can be reconstructed by metal artifact reduction software (MARS) to reduce metal artifact.


OBJECTIVE
To evaluate the degree of metal artifacts reduction and vessel visualization around the platinum coils using dual energy CT with MARS.


METHODS
Dual energy CT was performed using a Discovery CT750 HD scanner (GE Healthcare, Milwaukee, WI, USA). In a phantom study, we measured the mean standard deviation within regions of interest around a 10-mm-diameter platinum coil mass on MI with and without MARS. Thirteen patients who underwent CTA after endovascular embolization for cerebral aneurysm with platinum coils were included in a clinical study. We visually assessed the arteries around the platinum coil mass on MI with and without MARS.


RESULTS
Each standard deviation near the coil mass on MI with MARS was significantly lower than that without MARS in a phantom study. On CTA of a clinical study, better visibility of neighboring arteries was obtained in 11 of 13 patients on MI with MARS compared to without MARS due to metal artifact reduction.


CONCLUSIONS
Dual energy CT with MARS reduces metal artifact of platinum coils, resulting in favorable vessel visualization around the coil mass on CTA after embolization.
Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, Japan shino-y@olive.plala.or.jp.
Yuki
Y
Shinohara
Division of Neurosurgery, Department of Neurological Sciences, Faculty of Medicine, Tottori University, Japan.
Makoto
M
Sakamoto
Division of Clinical Radiology, Tottori University Hospital, Yonago, Japan.
Naoki
N
Iwata
Division of Clinical Radiology, Tottori University Hospital, Yonago, Japan.
Junichi
J
Kishimoto
Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, Japan.
Keita
K
Kuya
Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, Japan.
Shinya
S
Fujii
Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, Japan.
Toshio
T
Kaminou
Division of Neurosurgery, Department of Neurological Sciences, Faculty of Medicine, Tottori University, Japan.
Takashi
T
Watanabe
Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, Japan.
Toshihide
T
Ogawa
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016477:Artifacts; D001488:Basilar Artery / Q000000981:diagnostic imaging; D002536:Cerebral Arteries / Q000000981:diagnostic imaging*; D003287:Contrast Media; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000628:therapy*; D007480:Iopanoic Acid / Q000031:analogs & derivatives; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D010984:Platinum; D011856:Radiographic Image Enhancement / Q000379:methods; D012189:Retrospective Studies; D012984:Software; D014057:Tomography, X-Ray Computed / Q000379:methods*
D003287:Contrast Media; D010984:Platinum; C038955:iopanoate glucuronide; D007480:Iopanoic Acid
CNS; CT angiography; aneurysms; metal artifact