Coronary CT angiography in patients with implanted cardiac devices: initial experience with the metal artefact reduction technique.
OBJECTIVE
Single-energy metal artefact reduction (SEMAR), a new technique that can now be used in routine CT examinations, has recently become applicable to volume data acquired with electrocardiography gating. We evaluated the effect of this technique on the visualization of the coronary arteries in patients harboring cardiac devices.


METHODS
We subjected 8 patients (7 males, 1 female; mean age 65.5 ± 11.3 years) with implanted cardiac devices to coronary CT angiography on a 320-slice CT scanner (Aquilion ONE Vision™; Toshiba Medical Systems Corp., Tokyo, Japan). Image data sets were reconstructed with and without SEMAR. Two radiologists visually evaluated the image quality based on metal artefacts from the electronic device leads using a four-point scale (1 = vessel not visible to 4 = minimal or no metal artefacts). Images with a score of 3 or 4 were considered diagnostic.


RESULTS
In both SEMAR and non-SEMAR data sets, 94 coronary artery segments were available for evaluation. Without SEMAR, 11 segments (11.7%) were rated as non-diagnostic; SEMAR improved the image quality of 9 of the 11 segments (81.8%), and the images became diagnostic.


CONCLUSIONS
SEMAR reduced metal artefacts from the electronic device leads and improved the image quality of the coronary arteries in patients with cardiac devices. Advances in knowledge: SEMAR has recently become applicable to volume data acquired with electrocardiography gating. SEMAR reduces metal artefacts elicited by electronic device leads and improves the image quality of the coronary arteries in patients with cardiac devices.
1 Department of Diagnostic Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Fuminari
F
Tatsugami
1 Department of Diagnostic Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Toru
T
Higaki
1 Department of Diagnostic Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Hiroaki
H
Sakane
1 Department of Diagnostic Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Wataru
W
Fukumoto
1 Department of Diagnostic Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Makoto
M
Iida
1 Department of Diagnostic Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Yasutaka
Y
Baba
2 Department of Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Chikako
C
Fujioka
3 Department of Cardiovascular Medicine, Hiroshima University, Minami-ku, Hiroshima, Japan.
Yasuki
Y
Kihara
4 Toshiba Medical Systems Corporation, Otawara-shi, Tochigi, Japan.
So
S
Tsushima
1 Department of Diagnostic Radiology, Hiroshima University, Minami-ku, Hiroshima, Japan.
Kazuo
K
Awai
D000368:Aged; D016477:Artifacts; D055424:Cardiac-Gated Imaging Techniques; D000072226:Computed Tomography Angiography / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007479:Iopamidol / Q000008:administration & dosage / Q000031:analogs & derivatives; D008297:Male; D008670:Metals; D010138:Pacemaker, Artificial; D011829:Radiation Dosage; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D012189:Retrospective Studies
D003287:Contrast Media; D008670:Metals; C057937:iomeprol; D007479:Iopamidol