In coronary computed tomography angiography (CTA),
prospective ECG triggering scanning can be used in patients with a stable sinus rhythm and a low heart rate [1,
In this technique,
the CT scan is usually performed at the center of the mid-diastole phase at around 75% of the R-R interval .
As the best phase for diagnosis varies from patient to patient,
redundant scan data (padding) centered on mid-diastole are usually acquired [3,
A final image for evaluation of the coronary arteries is...
Methods and Materials
Outline of the multi-phase data-averaging technique (Fig.
multiple data acquisitions of an object and their averaging at CT yields lower image noise than dose single data acquisition .
Our new method uses three different cardiac phase images to reduce image noise. While coronary CTA with prospective ECG-triggering is usually performed in the center of the mid-diastole phase,
data can be acquired at the off-center of the temporal window if redundant scan time (padding) is added.
We set the range and center of...
The mean heart rate during the acquisition of CT scans was 51.9 ± 5.1 bpm (range 45 - 63 bpm); the mean effective radiation dose was 4.9 ± 1.1 mSv.
Our quantitative image quality parameters are shown in Table 1.
The mean image noise on the de-noised images was significantly lower than on conventional 75% images (P < 0.01).
The CNR in the proximal coronary arteries was significantly higher on de-noised- than conventional 75% images (P < 0.01).
With our method,
image noise was reduced...
In our study,
the noise reduction rate increased in proportionto the time for the R-R interval.
Because a redundant temporal window (padding) was acquired in a very short time-width (70-80% of the R-R interval),
there was substantial overlapping among the three data sets of 70-,
and 80% images.
We posit that the time width in the 70-80% of the R-R interval correlates with the extent of overlap among the three images.
When the time width in the padding was long,
the overlap was small....
Feasibility of low-dose coronary CT angiography: first experience with prospective ECG-gating.
European heart journal.
Accuracy of low-dose computed tomography coronary angiography using prospective electrocardiogram-triggering: first clinical experience.
European heart journal.
Radiation-reduction strategies in cardiac computed tomographic angiography.
Feasibility of low-volume injections of contrast material with a...
Department of Diagnostic Radiology,
E-mail address: email@example.com