Enhancement performance of a 64-slice triple rule-out protocol vs 16-slice and 10-slice multidetector CT-angiography protocols for evaluation of aortic and pulmonary vasculature.
OBJECTIVE
To compare the enhancement of the pulmonary and aortic vasculature between a biphasic injection 64-slice, a single-phase injection 16-slice, and a single-phase injection 10-slice multidetector computed tomographic (CT) angiography (CTA) protocols.


METHODS
With institutional review board approval and Health Insurance Portability and Accountability Act compliance, 50 patients (16 men, 34 women; mean age, 51.5 years; range, 30-75 years) with atypical chest pain from the emergency department were scanned using a triple rule-out protocol on a 64-slice CT scanner. Pulmonary enhancement was compared with 50 patients (21 men, 29 women; mean age, 65.6 years; range, 38-90 years) imaged with a single-phase 16-slice pulmonary angiography protocol. Aortic enhancement was compared with 24 patients (12 men, 12 women; mean age, 66.1; range, 34-92 years) who were imaged with a 16-slice aortic dissection CTA protocol and to 25 patients (15 men, 10 women; mean age, 50.8 years; range, 20-83 years) imaged with a 10-slice aortic dissection CTA protocol. A 2-tailed Student t test or sign test was used to assess significant differences from a vascular attenuation cutoff value of 250 Hounsfield units (HU).


RESULTS
Individual mean pulmonary arterial and aortic attenuation values were statistically significantly less than 250 HU for the 16- and 10-slice protocols and statistically significantly more than 250 HU for the 64-slice protocols (P < 0.05). Mean pooled pulmonary attenuation values were more than 250 HU in 18% (9/50) of the 16-slice and in 93% (39/42) of the 64-slice protocols. Mean pooled aortic attenuation values were more than 250 HU in 18.4% (9/49) of the 10- and 16- and in 100% (42/42) of the 64-slice protocols.


CONCLUSIONS
The triple rule-out 64-slice biphasic injection breath hold CTA protocol provides significantly higher attenuation of aortic and pulmonary vasculature compared with our current 10- and 16-slice protocols.
Haidary
Ahmad
A
William Beaumont Hospital, Royal Oak, MI 48073, USA.
Bis
Kostaki
K
Vrachliotis
Thomas
T
Vrachiolitis
Thomas
T
Kosuri
Rajni
R
Balasubramaniam
Mamtha
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000784:Aortic Dissection / Q000000981:diagnostic imaging; D000792:Angiography / Q000379:methods*; D017545:Aortic Aneurysm, Thoracic / Q000000981:diagnostic imaging; D001027:Aortography / Q000379:methods*; D002637:Chest Pain / Q000000981:diagnostic imaging; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D007472:Iohexol; D008168:Lung / Q000098:blood supply* / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000000981:diagnostic imaging; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement / Q000379:methods*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014283:Triiodobenzoic Acids
D003287:Contrast Media; D014283:Triiodobenzoic Acids; D007472:Iohexol; C044834:iodixanol